bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and development of a piezoelectric-hydraulic hybrid actuator with quarter-wavelength tubes
Authors: Zhang Jun Jian , Qian Min , Pan Qiaosheng , Feng Zhihua
Published: September 2023

The piezoelectric hydraulic actuator is a hybrid device consisting of a hydraulic pump driven by a piezoelectric stack connected to a hydraulic cylinder. For this type of piezoelectric actuator, the inertial force caused by the flow pulsation of the liquid will inhibit the movement of the piezoelectric vibrator and reduce its output performance. To solve these issues, two tubes were embedded into the piezoelectric-hydraulic hybrid actuation system for the first time to act as mechanical bandstop filters by interfering with the propagation of acoustic waves. The acoustic power transmission loss of the tube is derived from the one-dimensional wave equation. According to the experimental results, when the excitation frequency is close to the optimal operating frequency corresponding to the tubes, the liquid pulsation rate is reduced, the influence of inertial force on the actuator is weakened, and the output performance is relatively significantly improved. This strategy finally leads to a maximum no-load velocity of 153.5 mm s−1 and a maximum blocking force of 261.5 N for the hybrid actuator with 300 mm tubes; the maximum no-load velocity and blocking force of the hybrid actuator with 500 mm tubes are 94.45 mm s−1 and 230 N, respectively. Furthermore, this strategy can be used in other electrohydraulic actuators to enhance their capabilities.
Gaussian variational method to Fermi-Hubbard model in one and two dimensions
Authors: Shi Yue-Ran , He Yuan-Yao , Liu Ruijin , Zhang Wei
Published: September 2023

The study of ground-state properties of the Fermi-Hubbard model is a long-lasting task in the research of strongly correlated systems, and is crucial for the understanding of notable quantum phenomena including superconductivity and magnetism. Owing to the exponentially growing complexity of the system, a quantitative analysis usually demands high computational cost and is restricted to small samples, especially in two or higher dimensions. Here, we introduce a variational method in the frame of fermionic Gaussian states, and obtain the ground states of one- and two-dimensional attractive Hubbard models via imaginary-time evolution. We calculate the total energy and benchmark the results in a wide range of interaction strength and filling factor with those obtained via exact two-body results, the density matrix renormalization group based on matrix product states (MPS), and projector Quantum Monte Carlo (QMC) method. For both 1D and 2D cases, the Gaussian variational method presents accurate results for total energy with a maximum systematic error

∼

4
%

in the intermediate interaction region. The accuracy of these results has negligible dependence on the system size. We further calculate the double occupancy and find excellent agreement with MPS and QMC, as well as the experimental results of cold quantum gases in optical lattices. The results suggest that the Gaussian pairing state is a good approximation to the ground states of attractive Hubbard model, in particular in the strong and weak coupling limits. Moreover, we generalize the method to the attractive Hubbard model with a finite spin-polarization, which can be mapped to the repulsive interaction case via particle-hole transformation, and obtain accurate results of ground state energy and double occupancy. Our work demonstrates the ability of the Gaussian variational method to extract ground state properties of strongly correlated many-body systems with negligible computational cost, especially of large size and in higher dimensions.
The Steward Observatory LEO Satellite Photometric Survey
Authors: Krantz Harrison , Pearce Eric C. , Block Adam
Published: September 2023

The Steward Observatory LEO Satellite Photometric Survey is a comprehensive observational survey to characterize the apparent brightness of the Starlink and OneWeb low Earth orbit satellites and evaluate the potential impact on astronomy. We report the results of over 16,000 independent measurements of nearly 2800 individual satellites. In addition to photometry, we also measured the astrometric position of each satellite and evaluated the accuracy of predicting satellite position with the available two-line element sets. The apparent brightness of a satellite seen in the sky is not constant and depends on the Sun-satellite-observer geometry. To capture this, we designed the survey to create an all-geometries set of measurements to fully characterize the brightness of each population of satellites as seen in the sky. We visualize the data with sky-plots that show the correlation of apparent brightness with on-sky position and relative Sun-satellite-observer geometry. The sky-plots show where in the sky the satellites are brightest. In addition to visual magnitudes, we also present two new metrics: the expected photon flux and the effective albedo. The expected photon flux metric assesses the potential impact on astronomy sensors by predicting the flux for a satellite trail in an image from a theoretical 1 m class telescope and sensor. The effective albedo metric assesses where a satellite is more reflective than baseline, which ties to the physical structure of the satellite and indicates the potential for brightness-reducing design changes. We intend to use this methodology and resulting data to inform the astronomy community about satellite brightness. Observing programs use a variety of telescopes and instruments and look at different parts of the sky. With the expected photon flux metric and a complete all-sky characterization of satellite brightness, observers can evaluate the potential impacts to their projects and possibly avoid the worst effects.
Graphical representations and worm algorithms for the O(N) spin model
Authors: Liu Longxiang , Zhang Lei , Tan Xiaojun , Deng Youjin
Published: September 2023

We present a family of graphical representations for the O(N) spin model, where N ≥ 1 represents the spin dimension, and N = 1, 2, 3 corresponds to the Ising, XY and Heisenberg models, respectively. With an integer parameter 0 ≤ ℓ ≤ N/2, each configuration is the coupling of ℓ copies of subgraphs consisting of directed flows and N − 2ℓ copies of subgraphs constructed by undirected loops, which we call the XY and Ising subgraphs, respectively. On each lattice site, the XY subgraphs satisfy the Kirchhoff flow-conservation law and the Ising subgraphs obey the Eulerian bond condition. Then, we formulate worm-type algorithms and simulate the O(N) model on the simple-cubic lattice for N from 2 to 6 at all possible ℓ. It is observed that the worm algorithm has much higher efficiency than the Metropolis method, and, for a given N, the efficiency is an increasing function of ℓ. Besides Monte Carlo simulations, we expect that these graphical representations would provide a convenient basis for the study of the O(N) spin model by other state-of-the-art methods like the tensor network renormalization.
Generation of spatially entangled states in a photonic molecule containing a quantum dot
Authors: Tsukanov A V , Kateev I Yu
Published: September 2023

A model of a quantum network node based on a photonic molecule (PM) containing a quantum dot, which acts as a source and a router of single photons and correlated photon pairs, is proposed. Methods for coherent control of spatially entangled states of the node by local modification of its optical properties are studied. The fidelity of reproduction of these states and their generation time are calculated. The possibility of temperature tuning of an optical spectrum of triangular and square PMs consisting of four GaAs microdisks is shown. The dependence of eigenmode wavelengths on temperature and the distance between the microdisks are calculated.
Effect of entanglement in the generalized photon subtraction scheme
Authors: Bashmakova E N , Korolev S B , Golubeva T Yu
Published: September 2023

The paper considers the possibility of generating different non-Gaussian states using the entangled state photon measurement scheme. In the paper, we have proposed a way to explicitly find the wave function and the Wigner function of the output state of this scheme. Moreover, the solutions found are not restricted to any particular case, but have maximum generality (depend on the number of measured photons and on all parameters of the scheme). Such a notation allowed us to carry out a complete analysis of the output states, depending on the scheme parameters. Using explicit expressions, we have analyzed the magnitude of non-Gaussianity of the output states, and we have revealed which particular states can be obtained in the proposed scheme. We have considered in detail a particular case of measurement (single photon measurement) and have shown that using explicit expressions for the output state wave function one can find scheme parameters to obtain states suitable for quantum error correction codes with a large fidelity value and high probability. The Schrodinger’s cat state with amplitude α = 2 can be obtained with fidelity F ≈ 0.88 and probability 18 percent, and the squeezed Schrodinger’s cat state (α = 0.5, R = 1) with fidelity F ≈ 0.98 and probability 22%.
Multivariable closed-loop control of deep brain stimulation for Parkinson’s disease
Authors: Fleming John E , Senneff Sageanne , Lowery Madeleine M
Published: September 2023

Objective. Closed-loop deep brain stimulation (DBS) methods for Parkinson’s disease (PD) to-date modulate either stimulation amplitude or frequency to control a single biomarker. While good performance has been demonstrated for symptoms that are correlated with the chosen biomarker, suboptimal regulation can occur for uncorrelated symptoms or when the relationship between biomarker and symptom varies. Control of stimulation-induced side-effects is typically not considered. Approach. A multivariable control architecture is presented to selectively target suppression of either tremor or subthalamic nucleus beta band oscillations. DBS pulse amplitude and duration are modulated to maintain amplitude below a threshold and avoid stimulation of distal large diameter axons associated with stimulation-induced side effects. A supervisor selects between a bank of controllers which modulate DBS pulse amplitude to control rest tremor or beta activity depending on the level of muscle electromyographic (EMG) activity detected. A secondary controller limits pulse amplitude and modulates pulse duration to target smaller diameter axons lying close to the electrode. The control architecture was investigated in a computational model of the PD motor network which simulated the cortico-basal ganglia network, motoneuron pool, EMG and muscle force signals. Main results. Good control of both rest tremor and beta activity was observed with reduced power delivered when compared with conventional open loop stimulation, The supervisor avoided over- or under-stimulation which occurred when using a single controller tuned to one biomarker. When DBS amplitude was constrained, the secondary controller maintained the efficacy of stimulation by increasing pulse duration to compensate for reduced amplitude. Dual parameter control delivered effective control of the target biomarkers, with additional savings in the power delivered. Significance. Non-linear multivariable control can enable targeted suppression of motor symptoms for PD patients. Moreover, dual parameter control facilitates automatic regulation of the stimulation therapeutic dosage to prevent overstimulation, whilst providing additional power savings.
Laser Injection Technique for Liquid Crystal Droplets with Arbitrary Shape
Authors: Chang Fengjiao , Guo Jin-Kun , Ling Jinzhong , Yuan Ying , Wang Xiaorui
Published: September 2023

We propose a simple and precise method for processing three-dimensional droplet structures of liquid crystal with arbitrary shapes. By irradiating liquid crystal emulsions with a laser beam, a photothermally induced Marangoni effect is introduced. This leads to the injection of water solution into the liquid crystal droplets. With the help of the elasticity of liquid crystal, the injected water solution spontaneously forms into monodispersed guest droplets which latterly self-assemble into branched droplet chains. This method enjoys great flexibility due to its non-contact and in-situ processing manner, allows the simultaneous and multiple processing of all liquid crystal droplets under the irradiation region, and offers excellent compatibility with technologies such as microfluidics. The proposed method is applicable in material science, photonics, and sensors.
Gouy Phase in the Presence of a Dielectric Interface
Authors: Zhao Xinying , Liang Huijian , Zhang Han , Pang Xiaoyan
Published: September 2023

The Gouy phase is investigated in the dielectric interface in the present paper. It is shown that the maximum intensity and wavefront spacing are closely related to the Gouy phase and are influenced by the parameters refractive indices, the distance between the interface and the geometric focus and semi-aperture angle. Our findings demonstrate that even small changes in refractive indices have a significant impact on the Gouy phase and offer an alternative perspective on how accurate the Gouy phase is. The results may have applications in optical microscope, in optical recording and in the high-resolution optical sensing system.
A Partial Discharge Acoustic Detection Method of the Switchgear Based on Wavelet Denoising
Authors: Shi Xin , Yu Hao , Mo Zhongyue
Published: September 2023

To ensure the safe operation of the power grid and accurately identify the acoustic signal of the partial discharge of the switchgear, a partial discharge acoustic detection method for switchgear based on wavelet denoising is proposed in this paper. First, the Gaussian mixture algorithm model is used to denoise the discharge acoustic signal; then, the feature extraction and training of the acoustic signal samples are carried out; finally, a classifier is used to complete the discharge state recognition. The experimental results show that the detection accuracy of the proposed detection algorithm can reach more than 90%, and the robustness is good in different noise environments.
Integrated Energy Scheduling Optimization Based on Improved Gray Wolf Algorithm
Authors: Shang Jiawei , Wang Chenxu , Zhang Shijun , Gong Xu , Kang Qinyu
Published: September 2023

An integrated energy system contains a lot of distributed energy resources, and various energy sources complement each other, which greatly improves energy and has a significant advantage in energy conservation and emissions reduction. According to various micro source power characteristics and the cold and hot electricity load demand, this paper establishes a multi-objective model of cold-hot electric installations and an integrated energy system, by considering the influence of DianZhuan gas equipment and economic costs, and enhances the precision of the target function. Compared with the basic multi-target gray wolf algorithm, the improved algorithm effectively reduces economic drain, wind abandoned and pollution discharge amount.
Experimental Transient Performance of Heat Sink with Phase Change Material and Movable Metal Foams Insert
Authors: Feng Biao , Li Dedi , Rong Yangyiming , Gao Jun , Zhou Jie , Luo Guanqun
Published: September 2023

The effects of embedding fixed and movable metal foams in composite PCMs on the transient performance were studied with pulsed heat loads experimentally under various powers and different cell sizes. Similar conclusions could be drawn both from the experimental and numerical results. It was shown that when fixed metal foams were solely adopted, the heat storage system performance could be enhanced by ∼24.6% by increasing the number of metal foams by three times at the heat flux of 56.1 W/cm2 and 15 ppi. When the movable technique was utilized, the heat transfer enhancement reached up to 36.9% under the same amount of metal foams for the same cell sizes and heat flux. The better performances were attributed to combined positive influences due to the adoption of the movable metal foam technique, which extends heat transfer area, improves heat conduction, and eases suppression of natural heat convection by cutting the amount of metal foams. Moreover, as cutting the amount of metal foams could obviously reduce the wastage of energy storage capacity, the movable metal foam technique demonstrated quite a promising future.
Calculating the area of a particular deformation region of an optical surface based on the finite element method
Authors: Su Ruifeng
Published: September 2023

To study the deformation of an optical surface and its effect on optical performance, a method based on the finite element method for calculating the area of a particular deformation region of an optical surface is proposed, and a concept of effective area ratio is further introduced to describe the effect of deformation on optical performance. The principle of the method is presented, and the deformation of a potassium dihydrogen phosphate (KH2PO4, KDP) crystal is studied using this method, while the calculation accuracy is discussed. The results demonstrate that the method and the concept of effective area ratio are available for studying the deformation of an optical surface and its effect on optical performance.
n-type CdTe:In for photovoltaics: in situ doping, type verification and compensation effects
Authors: Hobson Theodore D C , Thomas Luke , Phillips Laurie J , Jones Leanne A H , Smiles Matthew J , Don Christopher H , Thakur Pardeep K , Shiel Huw , Campbell Stephen , Barrioz Vincent , Dhanak Vin , Veal Tim , Major Jonathan D , Durose Ken
Published: September 2023

We explored the in-situ doping of cadmium telluride thin films with indium to produce n-type absorbers as an alternative to the near-universal choice of p-type for photovoltaic devices. The films were grown by close space sublimation from melt-synthesised feedstock. Transfer of the indium during film growth was limited to 0.0014%–0.014%—unless reducing conditions were used which yielded 14%–28% efficient transport. While chunks of bulk feedstock were verified as n-type by the hot probe method, carrier type of thin film material was only able to be verified by using hard x-ray photoelectron spectroscopy to determine the Fermi level position within the band gap. The assignment of n-type conductivity was consistent with the rectification behaviour of a p-InP/CdTe:In junction. However, chloride treatment had the effect of compensating n-CdTe:In to near-intrinsic levels. Without chloride, the highest dopant activation was 20% of the chemical concentration of indium, this being for a film having a carrier concentration of n = 2 × 1015 cm−3. However, the activation was often much lower, and compensation due to over-doping with indium and native defects (stoichiometry) are discussed. Results from preliminary bifacial devices comprising Au/P3HT/ZnTe/CdTe:In/CdS/FTO/glass are presented.
MuDCoD: multi-subject community detection in personalized dynamic gene networks from single-cell RNA sequencing
Authors: Şapcı Ali Osman Berk , Lu Shan , Yan Shuchen , Ay Ferhat , Tastan Oznur , Keleş Sündüz
Published: September 2023

Motivation

With the wide availability of single-cell RNA-seq (scRNA-seq) technology, population-scale scRNA-seq datasets across multiple individuals and time points are emerging. While the initial investigations of these datasets tend to focus on standard analysis of clustering and differential expression, leveraging the power of scRNA-seq data at the personalized dynamic gene co-expression network level has the potential to unlock subject and/or time-specific network-level variation, which is critical for understanding phenotypic differences. Community detection from co-expression networks of multiple time points or conditions has been well-studied; however, none of the existing settings included networks from multiple subjects and multiple time points simultaneously. To address this, we develop Multi-subject Dynamic Community Detection (MuDCoD) for multi-subject community detection in personalized dynamic gene networks from scRNA-seq. MuDCoD builds on the spectral clustering framework and promotes information sharing among the networks of the subjects as well as networks at different time points. It clusters genes in the personalized dynamic gene networks and reveals gene communities that are variable or shared not only across time but also among subjects.

Results

Evaluation and benchmarking of MuDCoD against existing approaches reveal that MuDCoD effectively leverages apparent shared signals among networks of the subjects at individual time points, and performs robustly when there is no or little information sharing among the networks. Applications to population-scale scRNA-seq datasets of human-induced pluripotent stem cells during dopaminergic neuron differentiation and CD4+ T cell activation indicate that MuDCoD enables robust inference for identifying time-varying personalized gene modules. Our results illustrate how personalized dynamic community detection can aid in the exploration of subject-specific biological processes that vary across time.

Availability and implementation

MuDCoD is publicly available at https://github.com/bo1929/MuDCoD as a Python package. Implementation includes simulation and real-data experiments together with extensive documentation.
When science and evidence is not enough: challenging the recommendations from the Commission on Human Medicines Isotretinoin Expert Working Group
Authors: Tan Eugene , Kennedy Harriet , Rademaker Marius
Published: September 2023

The Commission on Human Medicines (CHM) Isotretinoin Expert Working Group recently released a report with several major recommendations. The authors scrutinized the evidence cited by the CHM and presented the case that their recommendations undermine evidence-based medicine and scientific thinking.
Frequent allopolyploidy with distant progenitors in the moss genera Physcomitrium and Entosthodon (Funariaceae) identified via subgenome phasing of targeted nuclear genes
Authors: Patel Nikisha , Medina Rafael , Williams Lindsay D , Lemieux Olivia , Goffinet Bernard , Johnson Matthew G
Published: September 2023

Allopolyploids represent a new frontier in species discovery among embryophytes. Within mosses, allopolyploid discovery is challenged by low morphological complexity. The rapid expansion of sequencing approaches in addition to computational developments to identifying genome merger and whole-genome duplication using variation among nuclear loci representing homeologs has allowed for increased allopolyploid discovery among mosses. Here, we test a novel approach to phasing homeologs within loci and phasing loci across subgenomes, or subgenome assignment, called Homologizer, in the family Funariaceae. We confirm the intergeneric hybrid nature of Entosthodon hungaricus, and the allopolyploid origin of Physcomitrium eurystomum and one population of Physcomitrium collenchymatum. We also reveal that hybridization gave rise to Physcomitrium immersum, as well as to yet unrecognized lineages sharing the phenotype of Physcomitrium pyriforme and Physcomitrium sphaericum. Our findings demonstrate the utility of our approach when working with polyploid genomes, and its value in identifying progenitor species using target capture data.
Constraint on the event rate of general relativistic instability supernovae from the early JWST deep field data
Authors: Moriya Takashi J , Harikane Yuichi , Inoue Akio K
Published: September 2023

General relativistic instability supernovae (GRSNe) at 10 ≲ z ≲ 15 are predicted to be observed as red faint point sources, and they can be detected only in the reddest filters in James Webb Space Telescope (JWST)/NIRCam (F444W and F356W). They should be observed as persistent point sources with little flux variations for a couple of decades because of time dilation. We search for static point sources detected only in the F444W filter or only in the F444W and F356W filters in the early JWST deep field data. No real point source of such kind is identified. Therefore, the GRSN rate at 10 ≲ z ≲ 15 is constrained to be less than ∼8 × 10−7 Mpc−3 yr−1 for the first time.
Follow-up analyses to the O3 LIGO–Virgo–KAGRA lensing searches
Authors: Janquart J , Wright M , Goyal S , Chan J C L , Ganguly A , Garrón Á , Keitel D , Li A K Y , Liu A , Lo R K L , Mishra A , More A , Phurailatpam H , Prasia P , Ajith P , Biscoveanu S , Cremonese P , Cudell J R , Ezquiaga J M , Garcia-Bellido J , Hannuksela O A , Haris K , Harry I , Hendry M , Husa S , Kapadia S , Li T G F , Magaña Hernandez I , Mukherjee S , Seo E , Van Den Broeck C , Veitch J
Published: September 2023

Along their path from source to observer, gravitational waves may be gravitationally lensed by massive objects leading to distortion in the signals. Searches for these distortions amongst the observed signals from the current detector network have already been carried out, though there have as yet been no confident detections. However, predictions of the observation rate of lensing suggest detection in the future is a realistic possibility. Therefore, preparations need to be made to thoroughly investigate the candidate lensed signals. In this work, we present some follow-up analyses that could be applied to assess the significance of such events and ascertain what information may be extracted about the lens-source system by applying these analyses to a number of O3 candidate events, even if these signals did not yield a high significance for any of the lensing hypotheses. These analyses cover the strong lensing, millilensing, and microlensing regimes. Applying these additional analyses does not lead to any additional evidence for lensing in the candidates that have been examined. However, it does provide important insight into potential avenues to deal with high-significance candidates in future observations.
The Syphilis Epidemic Among Heterosexuals Is Accelerating: Evidence From King County, Washington
Authors: Berzkalns Anna , Ramchandani Meena S , Cannon Chase A , Kerani Roxanne P , Dombrowski Julie C , Golden Matthew R
Published: September 2023

Background

We characterized the rapid increase in syphilis among cisgender women in King County, Washington, and compared it with trends among cisgender men who have sex with men.

Method

We used surveillance data from King County, 2007 to 2022, to describe incidence trends stratified by syphilis stage, gender, and gender of sex partners; trends in pregnant cases and congenital syphilis; and trends in rapid plasma reagin titer at diagnosis among late/unknown duration cases. We used joinpoint regression to analyze trends.

Results

Among cisgender women, all-stage syphilis incidence remained stable from 2007 to 2010 but then increased by 16.3% per year (95% CI, 12.0%–20.7%) from 2010 to 2020 and 90.1% per year (95% CI, 26.4%–185.9%) from 2020 to 2022. Early syphilis rates rose gradually from 2007 to 2017 (18% per year; 95% CI, 7.4%–29.6%) and then rapidly from 2017 to 2022 (62.5% per year; 95% CI, 24.1%–112.9%). In contrast, the increase in late/unknown duration syphilis incidence was delayed. Among cisgender men who have sex with women, all-stage syphilis remained stable from 2007 to 2014 and increased 25.0% per year (95% CI, 14.0%–37.0%) from 2014 to 2022. Syphilis incidence increased steadily among men who have sex with men, with all-stage incidence increasing 7.0% per year (95% CI, 4.8%–9.2%) from 2007 to 2022. Median rapid plasma reagin titer among late/unknown duration cases increased significantly over the analysis period.

Conclusions

An explosive epidemic of syphilis is ongoing in King County. The delayed increase in asymptomatic late/unknown duration cases relative to early symptomatic cases suggests that there is a large and growing reservoir of recently acquired undiagnosed syphilis in women. New clinical and public health activities are urgently needed to control the growing epidemic.
Investigating acute hepatitis of unknown origin in children
Authors: Heavey Elizabeth , Peterson Kathleen
Published: September 2023

In late 2021, the CDC was alerted to a cluster of children with hepatitis of unknown etiology at a US hospital. Similar reports began to emerge out of Europe. This article discusses the systematic investigation into these cases.
ChatGPT and Generative Artificial Intelligence for Medical Education: Potential Impact and Opportunity
Authors: Boscardin Christy K. , Gin Brian , Golde Polo Black , Hauer Karen E.
Published: September 2023

ChatGPT has ushered in a new era of artificial intelligence (AI) that already has significant consequences for many industries, including health care and education. Generative AI tools, such as ChatGPT, refer to AI that is designed to create or generate new content, such as text, images, or music, from their trained parameters. With free access online and an easy-to-use conversational interface, ChatGPT quickly accumulated more than 100 million users within the first few months of its launch. Recent headlines in the popular press have ignited concerns relevant to medical education over the possible implications of cheating and plagiarism in assessments as well as excitement over new opportunities for learning, assessment, and research. In this Scholarly Perspective, the authors offer insights and recommendations about generative AI for medical educators based on literature review, including the AI literacy framework. The authors provide a definition of generative AI, introduce an AI literacy framework and competencies, and offer considerations for potential impacts and opportunities to optimize integration of generative AI for admissions, learning, assessment, and medical education research to help medical educators navigate and start planning for this new environment. As generative AI tools continue to expand, educators need to increase their AI literacy through education and vigilance around new advances in the technology and serve as stewards of AI literacy to foster social responsibility and ethical awareness around the use of AI.
Beware False Growth Mindset: Building Growth Mindset in Medical Education Is Essential but Complicated
Authors: Memari Milad , Gavinski Katherine , Norman Marie K.
Published: September 2023

Mindset theory aims to explain how learners’ beliefs about intelligence and learning affect how they perceive effort, react to failure, and respond to feedback in challenging learning contexts. Mindset theory distinguishes between growth mindset (the belief that human capacities can be developed over time) and fixed mindset (the belief that human capacities are inherent and unchangeable). Efforts to develop growth mindset in learners have shown a wide range of benefits, including positive effects on students’ resilience, commitment to lifelong learning, and persistence in a field of study, with notable impacts on learners who are struggling, learners from minoritized groups, and women in scientific fields. In recent years, mindset theory interventions have caught the interest of medical educators hoping to engage learners as partners in their own learning and progression to competence. Educators hoping to apply this theory to educational programs and learner-teacher interactions in ways that promote growth mindsets would benefit from awareness of the concept of false growth mindset, a term coined by Carol Dweck to refer to common pitfalls in the theory's application. In this article, the authors highlight important findings from mindset interventions in medical education, identify common pitfalls of false growth mindset in the context of medical learners, and offer suggestions for how educators and institutions can better instigate changes to promote growth mindsets within medical education.
SHARPening Residency Selection: Implementing a Systematic Holistic Application Review Process
Authors: Igarabuza Laura , Gusoff Geoffrey M. , Maharaj-Best Ayiti-Carmel , Baylson Margaret J. , Betancourt Renée M. , Nicklin David E. , Wang Jenny Y.
Published: September 2023

Problem

Traditional metrics used in residency application review processes are systematically biased against applicants from minoritized communities that are underrepresented in medicine (URiM). These biases harm not just URiM applicants but also residency programs and patients. Although several residency programs have implemented holistic reviews to mitigate these biases, few tested tools exist that can be adapted and implemented in a wide variety of settings within academic medicine.

Approach

This article describes advances made in the third year of a longitudinal, ongoing quality improvement project that used the A3 framework to improve recruitment of URiM residents to a family medicine residency program. The authors devised a systematic holistic application review process (SHARP) to determine which applicants to invite to interview with the program. SHARP's development began in August 2019, and after significant discussion with program leadership and iterations of rubric refinement, the program adopted SHARP in September 2020 to review applications for the 2021 application cycle.

Outcomes

Compared with the 2016 to 2020 period before SHARP implementation, data from the 2021 and 2022 residency application cycles after SHARP implementation showed a significant increase in the proportion of interviewed candidates who identify as URiM (from 23% to 38%, P < .001) and matched candidates who identify as URiM (from 27% to 62%, P = .004). There was also a notable increase in the number and diversity of reviewers who evaluated applicants to the program.

Next Steps

SHARP is a promising tool to mitigate the effects of racism and other biases against URiM applicants to residency programs. Residency programs across specialties may benefit from adopting SHARP and adapting it based on their own goals and priorities.
“It’s What We Can Do Right Now”: Professional Identity Formation Among Internal Medicine Residents During the COVID-19 Pandemic
Authors: Madrazo Lorenzo , Zhang Grace , Bishop Kristen A. , Appleton Andrew , Joneja Mala , Goldszmidt Mark
Published: September 2023

Purpose

The COVID-19 pandemic represents a consequential moment of disruption for medical training that has far-reaching implications for professional identity formation (PIF). To date, this has not been studied. As medical education grapples with a postpandemic era, it is essential to gain insight into how the pandemic has influenced PIF to better support its positive influences and mitigate its more detrimental effects. This study examined how PIF occurred during the COVID-19 pandemic to better adapt future medical training.

Method

Constructivist grounded theory guided the iterative data collection and analyses. The authors conducted semistructured group interviews with 24 Ontario internal medicine residents in postgraduate years (PGYs) 1 to 3 between November 2020 and July 2021. Participants were asked to reflect on their day-to-day clinical and learning experiences during the pandemic.

Results

Twenty-four internal medicine residents were interviewed (12 PGY-1 [50.0%], 9 PGY-2 [37.5%], and 3 PGY-3 [12.5%]). Participants described how navigating patient care and residency training through the pandemic consistently drew their attention to various system problems. How participants responded to these problems was shaped by an interplay among their personal values, their level of personal wellness or burnout, self-efficacy, institutional values, and the values of their supervisors and work community. As they were influenced by these factors, some were led toward acting on the problem(s) they identified, whereas others had a sense of resignation and deferred action. These interactions were evident in participants' experiences with communication, advocacy, and learning.

Conclusions

Residents' professional identities are continuously shaped by how they perceive, reconcile, and address various challenges. As residents navigate tensions between personally held values and apparent system values, individuals in supervisory positions should be mindful of their influence as role models who empower values and practices that are recognized by participants to be important aspects of physician identity.
Optimal Dosing of Levetiracetam for Seizure Prophylaxis in Critically Ill Patients: A Prospective Observational Study
Authors: Valdes Eduard , Fang Taolin , Boffa Michael , Frontera Jennifer A.
Published: September 2023

OBJECTIVES:

Critically ill patients eliminate levetiracetam (LEV) more rapidly than healthy controls, yet low doses are commonly used for seizure prophylaxis in the ICU setting. We compared the rates of achievement of target serum levels and new onset seizure (clinical and/or electrographic) among patients who received low (500 mg bid) versus high (750–1,000 mg bid) dose LEV.

DESIGN:

Prospective, observational study.

SETTING:

Tertiary care, academic center.

PATIENTS:

We included patients who received prophylactic LEV following traumatic brain injury, intracerebral hemorrhage, spontaneous subarachnoid hemorrhage, or supratentorial neurosurgery between 2019 and 2021. Patients with a history of seizure, antiseizure medication use, or renal failure requiring dialysis were excluded.

INTERVENTIONS:

None.

Measurements:

LEV levels were obtained at steady state. The impact of low-dose versus high-dose LEV on the primary outcome of target LEV levels (12–46 μg/mL), and the secondary outcome of clinical and/or electrographic seizure, were assessed using multivariable logistic regression analyses adjusting for age, LEV loading dose, BMI, primary diagnosis and creatinine clearance (CrCl).

Main Results:

Of the 205 subjects included in analyses, n = 106 (52%) received LEV 500 mg bid (median 13 mg/kg/d), and n = 99 (48%) received LEV 750–1,000 mg bid (median 25 mg/kg/d). Overall, 111 of 205 patients (54%) achieved target levels: 48 (45%) from the low-dose group versus 63 (64%) from the high-dose group (odds ratio [OR] 2.1; 95% CI, 1.1–3.7; p = 0.009). In multivariable analyses, high-dose LEV predicted target levels (adjusted OR [aOR] 2.23; 95% CI, 1.16–4.27; p = 0.016), and was associated with lower seizure odds (aOR 0.32; 95% CI, 0.13–0.82; p = 0.018) after adjusting for age, loading dose, BMI, diagnosis, and CrCl.

CONCLUSIONS:

Underdosing of LEV was common, with only 54% of patients achieving target serum levels. Higher doses (750–1,000 mg bid) were more than twice as likely to lead to optimal drug levels and reduced the odds of seizure by 68% compared with low-dose regimens (500 mg bid).
Characterization of Polymicrobial and Antibiotic-Resistant Infectious Keratitis in a County Hospital Setting
Authors: Chan Lawrence , Lopez Jacqueline B. , Saifee Murtaza , Padmanabhan Sriranjani , Chan Matilda F. , Yung Madeline
Published: September 2023

Purpose:

Infectious keratitis is a serious cause of visual impairment, particularly in low-income communities. This study examines the associations between social risk factors and polymicrobial keratitis, multidrug resistance, pathogen spectrum, and outcomes at a county hospital.

Methods:

We performed a retrospective study of Zuckerberg San Francisco General Hospital patients treated for infectious keratitis from 2010 to 2021. Multivariable regression was performed to analyze the relationships between social, medical, and psychiatric risk factors with polymicrobial growth, multidrug resistance, and clinical outcomes.

Results:

Of 174 patients with infectious keratitis, 44 (25%) had polymicrobial growth. Six patients (14%) with polymicrobial growth had multidrug-resistant organisms. Homeless patients were more likely to present with polymicrobial infection (odds ratio [OR] 3.4, P = 0.023), and polymicrobial infections were associated with multidrug-resistant organisms (P = 0.018). Smoking, drug use, HIV positivity, prior corneal pathology, and contact lens use were not associated with an increased risk of polymicrobial infection. Eleven patients (6.3%) were started on topical antibiotics before presentation; of these, none developed polymicrobial infections or multidrug-resistant organisms. Polymicrobial infections increased the likelihood to initiation of fortified antibiotics (OR 2.9, P = 0.011) but did not impact ulcer size, final visual acuity, time to resolution, or likelihood of emergent procedures.

Conclusions:

Homelessness correlates with an increased risk of polymicrobial keratitis and subsequent multidrug resistance, supporting initiation of broad antibiotic coverage in this population. Prior topical antibiotics did not increase risk of polymicrobial infection. Polymicrobial infection did not significantly worsen clinical outcomes.
Motor and Sensory Balance Deficits in Individuals Immediately After COVID-19, a Cohort Study
Authors: Wrisley Diane M. , Garavito Eder A. , Jones Brittany , Klintworth-Kirk Tamara , Poole Ashley K.
Published: September 2023

Background and Purpose:

Individuals with cardiorespiratory dysfunction demonstrate postural instability and increased risk of falls. Given that coronavirus disease (COVID-19) is commonly defined as a respiratory condition, it could be presumed that these patients may demonstrate similar balance deficits. This study aimed to determine deficits and characterize balance dysfunction (sensory or motor) in hospitalized patients classified as “COVID-19 recovered.”

Methods:

Twenty-five participants consented for this study. Participants completed the Activity-Specific Balance Confidence Scale (ABC), a questionnaire about dizziness, the Timed “Up & Go” (TUG), and the modified Clinical Test of Sensory Interaction and Balance in a single session. The percentage of subjects who scored abnormal on the outcome measures was calculated. Correlations between demographics, respiratory function, and clinical outcome measures were determined using Spearman correlation coefficient.

Results:

All participants had abnormal scores on the TUG, 88% had abnormal scores on the ABC, and 48% of the subjects had abnormal scores on standing on foam eyes closed indicating difficulty using vestibular information. No correlation coefficient above 0.50 was found between the demographic information, respiratory function, and clinical outcome measures.

Discussion:

Clinical outcome measure scores did not correlate with respiratory function indicating that the deficits may be due to the extrapulmonary components of COVID-19.

Conclusion:

Both young and older adults presented with motor and sensory balance deficits acutely after COVID-19 infection. It is recommended that individuals acutely post–COVID-19 receive education and interventions to increase mobility, improve balance, decrease fall risk, and specifically receive activities that stimulate the vestibular system.
Daily Summer Temperatures and Hospitalization for Acute Cardiovascular Events: Impact of Outdoor PM2.5 Oxidative Potential on Observed Associations Across Canada
Authors: Weichenthal Scott , Lavigne Eric , You Hongyu , Pollitt Krystal , Shin Tim , Kulka Ryan , Stieb Dave M. , Hatzopoulou Marianne , Evans Greg , Burnett Richard T.
Published: September 2023

Background:

Oxidative stress plays an important role in the health impacts of both outdoor fine particulate air pollution (PM2.5) and thermal stress. However, it is not clear how the oxidative potential of PM2.5 may influence the acute cardiovascular effects of temperature.

Methods:

We conducted a case–crossover study of hospitalization for cardiovascular events in 35 cities across Canada during the summer months (July–September) between 2016 and 2018. We collected three different metrics of PM2.5 oxidative potential each month in each location. We estimated associations between lag-0 daily temperature (per 5ºC) and hospitalization for all cardiovascular (n = 44,876) and ischemic heart disease (n = 14,034) events across strata of monthly PM2.5 oxidative potential using conditional logistical models adjusting for potential time-varying confounders.

Results:

Overall, associations between lag-0 temperature and acute cardiovascular events tended to be stronger when outdoor PM2.5 oxidative potential was higher. For example, when glutathione-related oxidative potential (OPGSH) was in the highest tertile, the odds ratio (OR) for all cardiovascular events was 1.040 (95% confidence intervals [CI] = 1.004, 1.074) compared with 0.980 (95% CI = 0.943, 1.018) when OPGSH was in the lowest tertile. We observed a greater difference for ischemic heart disease events, particularly for older subjects (age >70 years).

Conclusions:

The acute cardiovascular health impacts of summer temperature variations may be greater when outdoor PM2.5 oxidative potential is elevated. This may be particularly important for ischemic heart disease events.
Inpatient versus Outpatient Immediate Alloplastic Breast Reconstruction: Recent Trends, Outcomes, and Safety
Authors: Little Andrea K. , Patmon Darin L. , Sandhu Harminder , Armstrong Shannon , Anderson Daniella , Sommers Megan
Published: September 2023

Background:

Immediate alloplastic breast reconstruction was traditionally performed as an inpatient procedure. Despite several reports in the literature demonstrating comparable safety outcomes, there remains hesitancy to accept breast reconstruction performed as an outpatient procedure.

Methods:

A retrospective review of National Surgical Quality Improvement Program data from 2014 to 2018 was utilized to evaluate recent trends and 30-day postoperative complication rates for inpatient versus outpatient immediate prosthetic-based breast reconstruction. Propensity score matching was used to obtain comparable groups.

Results:

During the study period, 33,587 patients underwent immediate alloplastic breast reconstruction. Of those, 67.5% of patients were discharged within 24 hours, and 32.4% of patients had a hospital stay of more than 24 hours. Immediate alloplastic reconstruction had an overall growth rate of 16.9% from 2014 to 2018. After propensity score matching, intraoperative variables that correlated with significantly increased inpatient status included increased work relative value units (16.3 ± 2.3 versus 16.2 ± 2.6; P < 0.001), longer operative times (228 ± 86 versus 206 ± 77; P < 0.001), and bilateral procedure (44.0% versus 43.5%; P < 0.001). There were higher rates of pulmonary embolism, wound dehiscence, urinary tract infection, transfusions, sepsis, readmissions, and reoperations in the group with the longer hospital stay.

Conclusion:

Based on increased complication rates and costs in the inpatient setting, we propose outpatient reconstructive surgery as a safe and cost-effective alternative for immediate alloplastic breast reconstruction.