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1.
BMC Psychiatry ; 24(1): 384, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38783275

RESUMO

BACKGROUND: This study investigated the role of emotion regulation in relation to the links between fear of missing out (i.e., FOMO) and two components of problematic internet use: problematic social media use and doomscrolling. METHODS: Participants (N = 603, Mage = 30.41, SDage = 7.64; 49.1% male-identifying) completed measures of fear of missing out, intrapersonal and interpersonal emotion regulation, and problematic social media use, and doomscrolling. A parallel mediation model was tested to examine the nature of the associations between fear of missing out, intrapersonal, and interpersonal emotion regulation, in accounting for variance in the outcome measures. RESULTS: Analyses revealed that the effect of fear of missing out on problematic social media use was fully mediated by both intrapersonal and interpersonal emotion regulation. In contrast, the effect on doomscrolling was fully mediated by intrapersonal emotion regulation only. CONCLUSIONS: Findings clarify the role of emotion regulation in explaining the relationship between fear of missing out and two types of problematic internet use, indicating a need to consider individual differences in emotion regulation in an evolving social media landscape.


Assuntos
Regulação Emocional , Medo , Transtorno de Adição à Internet , Relações Interpessoais , Mídias Sociais , Humanos , Masculino , Feminino , Adulto , Transtorno de Adição à Internet/psicologia , Medo/psicologia , Amigos/psicologia , Adulto Jovem , Uso da Internet
2.
Phys Rev Lett ; 130(17): 173202, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172235

RESUMO

We report on the first demonstration of transport of a multispecies ion crystal through a junction in a rf Paul trap. The trap is a two-dimensional surface-electrode trap with an X junction and segmented control electrodes to which time-varying voltages are applied to control the shape and position of potential wells above the trap surface. We transport either a single ^{171}Yb^{+} ion or a crystal composed of a ^{138}Ba^{+} ion cotrapped with the ^{171}Yb^{+} ion to any port of the junction. We characterize the motional excitation by performing multiple round-trips through the junction and back to the initial well position without cooling. The final excitation is then measured using sideband asymmetry. For a single ^{171}Yb^{+} ion, transport with a 4 m/s average speed induces between 0.013±0.001 and 0.014±0.001 quanta of excitation per round-trip, depending on the exit port. For a Ba-Yb crystal, transport at the same speed induces between 0.013±0.001 and 0.030±0.002 quanta per round-trip of excitation to the in-phase axial mode. Excitation in the out-of-phase axial mode ranges from 0.005±0.001 to 0.021±0.001 quanta per round-trip.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37382857

RESUMO

Underrepresented students in medicine (URM) have more negative perceptions of the medical school learning environment (LE), a phenomenon that can contribute to higher rates of burnout and attrition in these populations. The hidden curriculum (HC)-defined as a set of values informally conveyed to learners through clinical role-modeling-is a LE socialization construct that has been critically examined for its role in shaping students' professional identities. Yet differences in how URMs and non-URMs experience the HC remain underexplored. The study used a pragmatic approach that drew on elements of grounded theory and employed both deductive and inductive reasoning. Investigators conducted qualitative, semi-structured interviews with a purposive sample of 13 URM and 21 non-URM participants at a Bronx, NY medical school. Interviews examined student experiences and reactions to the HC. Both cohorts witnessed patient disparagement and mistreatment. However, from these encounters, URM participants expressed more moral injury-the adverse emotional consequence of feeling pressured to accept ideologically incongruent values. URMs were also more likely to describe resisting the HC. Differences in group reactions appeared to arise from URMs' identity resonance with patients' lived experiences. Participants across cohorts emphasized increasing URM recruitment as one step toward mitigating these circumstances. URM participants experienced more distress and offered more resistance to the HC relative to non-URMs. The etiology of these differential reactions may stem from relative barriers in negotiating personal and professional identities. As such, URMs' perceptions of the LE may be adversely impacted given their more negative interactions with the HC.

4.
Adv Exp Med Biol ; 1406: 209-224, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37016117

RESUMO

Medical students use several supplementary digital resources to support learning. Majority of these supplementary resources enhance learning by recall and repetition. A few examples of these resources are concept maps, flashcards (FCs), and self-testing tools. Traditionally, paper-based FCs are used in higher education. The concept of paper-based FCs is extended to the digital world in the form of electronic/web-based FCs. The use of electronic/digital flashcards has been reported to review course material in the medical school curriculum. Some of the medical school coursework requires students to acquire visual skills, for example, histology and pathology. Students, who do not have prior knowledge of the basic content on histology and pathology struggle to identify microscopic tissues and organs. Therefore, students look for other supplementary resources to support visual learning. Digital resources like Anki, Quizlet, and Osmosis provide study tools that support visual skills. A review of the literature revealed only a few publications pertaining to the use of digital testing tools for histology education in medical school curriculum. In the medical histology course at the Albert Einstein College of Medicine (Einstein), Bronx, NY, first-year medical students used a game-based platform (Quizlet) to review image-based histology course content in the form of four Quizlet study sets. Students chose from six Quizlet study tools (Flashcards, Learn, Speller, Test, Match, and Race/Gravity) to review the image-based course material and test their knowledge on accurate identification of histological images. The data on student usage of study tools was tracked and analyzed for 4 years (Graduating Classes of 2018 to 2021) to calculate: the total usage of the game-based study tools (Flashcards, Learn, Speller, Test, Match, and Race/Gravity) over the period of 4 years, total percent usage over 4 years of each game-based study tools (Flashcards, Learn, Speller, Test, Match, and Race/Gravity) in each of the four Quizlet study sets and to identify the preferred game-based study tool. The data showed a consistent year-on-year increase in usage of game-based study tools by 50% (M = 445 in 2018 compared to M = 849 in 2021). For the four Quizlet study sets the percent usage of each study tool Flashcards, Learn, Test, Match, Gravity, and Speller was tracked and combined across the four academic years. It was found that Flashcards were used significantly more frequently than any other tool and this was followed by Learn, Test, Match, Gravity, and Speller (p < 0.0001 using chi-square). The study concludes that flashcards are the preferred study tool used by students to acquire visual skills for identifying histological images and could be incorporated when designing online study tools.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Aprendizagem , Currículo , Educação de Graduação em Medicina/métodos , Escolaridade
5.
Teach Learn Med ; : 1-11, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37450615

RESUMO

Phenomenon: Improving the learning environment (LE), particularly for students underrepresented in medicine (URM), has become an important goal for institutions that provide undergraduate and graduate medical education. Until recently, research and intervention development have been limited by the lack of comprehensive theoretical frameworks. A multi-dimensional conceptual model of the medical school environment, developed by Gruppen and colleagues in 2019, provides a useful framework for guiding research and interventions in this area.Approach: Using Gruppen et al's model, this study investigated experiences of the LE from the perspectives of both URM and non-URM students at a medical school in New York City. In examining experiences of the organizational, social, and physical domains of the LE, we sought to explore the symbolic and experiential links across domains and identify concrete needs for improvement.Findings: Institutional structures and policies, features of the built environment, and social relationships that put learning first and generated a sense of community were highly valued. Although both URM and non-URM students shared many perceptions and experiences, URM students expressed heightened vulnerability to the experiences of devaluation and exclusion.Insights: All participants in the study greatly appreciated aspects of the LE that made them feel like valued members of the community. Medical schools should approach the task of improving the LE for URM students using a comprehensive, multi-dimensional approach.

6.
J Arthroplasty ; 38(10): 2068-2074, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37236287

RESUMO

BACKGROUND: Dynamic radiographic measurements of 3-dimensional (3-D) total knee arthroplasty (TKA) kinematics have provided important information for implant design and surgical technique for over 30 years. However, current methods of measuring TKA kinematics are too cumbersome, inaccurate, or time-consuming for practical clinical application. Even state-of-the-art techniques require human-supervision to obtain clinically reliable kinematics. Eliminating human supervision could potentially make this technology practical for clinical use. METHODS: We demonstrate a fully autonomous pipeline for quantifying 3D-TKA kinematics from single-plane radiographic imaging. First, a convolutional neural network (CNN) segmented the femoral and tibial implants from the image. Second, those segmented images were compared to precomputed shape libraries for initial pose estimates. Lastly, a numerical optimization routine aligned 3D implant contours and fluoroscopic images to obtain the final implant poses. RESULTS: The autonomous technique reliably produces kinematic measurements comparable to human-supervised measures, with root-mean-squared differences of less than 0.7 mm and 4° for our test data, and 0.8 mm and 1.7° for external validation studies. CONCLUSION: A fully autonomous method to measure 3D-TKA kinematics from single-plane radiographic images produces results equivalent to a human-supervised method, and may soon make it practical to perform these measurements in a clinical setting.


Assuntos
Artroplastia do Joelho , Humanos , Fenômenos Biomecânicos , Raios X , Fêmur , Aprendizado de Máquina
7.
Phys Rev Lett ; 128(9): 093401, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302815

RESUMO

We observe and study a special ground state of bosons with two spin states in an optical lattice: the spin-Mott insulator, a state that consists of repulsively bound pairs that is insulating for both spin and charge transport. Because of the pairing gap created by the interaction anisotropy, it can be prepared with low entropy and can serve as a starting point for adiabatic state preparation. We find that the stability of the spin-Mott state depends on the pairing energy, and observe two qualitatively different decay regimes, one of which exhibits protection by the gap.

8.
J Am Acad Dermatol ; 83(5): 1294-1297, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32649961

RESUMO

BACKGROUND: Platelet-rich plasma (PRP) may be a useful treatment for androgenetic alopecia (AGA), although objective studies are needed. OBJECTIVE: To determine whether PRP injections improve female AGA. METHOD: Prospective randomized controlled trial of 30 women diagnosed with AGA. Patients received subdermal scalp injections of Eclipse system PRP or placebo saline at weeks 0, 4, and 8. Outcome measures were changes in hair density (hair/cm2), hair caliber (mm), and blinded global photographic assessment (improved or not improved) at week 24. RESULTS: Blinded global photographic assessment indicated that 57% of patients receiving PRP versus 7% of patients receiving saline improved at week 24 from baseline (P < .01). Compared to baseline, there was improvement in mean density in the PRP group versus the placebo group at week 8 (+71.1 vs -26.7 hairs/cm2; P < .01) and week 24 (+105.9 vs -52.4 hairs/cm2; P < .01). Compared to baseline, there was improvement in mean caliber in the PRP group versus the placebo group at week 8 (+0.0043 vs -0.0034 mm; P < .01) and week 24 (+0.0053 vs -0.0060 mm; P < .01). Adverse effects included headache, scalp tightness, swelling, redness, and postinjection bleeding. LIMITATIONS: Two patients lost to follow-up. CONCLUSIONS: PRP with the Eclipse system is a safe and effective intervention for female AGA.


Assuntos
Alopecia/terapia , Plasma Rico em Plaquetas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Injeções Intradérmicas , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego
9.
J Nurs Scholarsh ; 52(4): 344-351, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32396267

RESUMO

PURPOSE: The purpose of this article is to describe the creation and outcomes of a collaborative model and care facility for opioid overdose and addiction treatment based on compassion, patience, and respect: The Maryhaven Addiction Stabilization Center (MASC). APPROACH: MASC was created with the vision to serve clients who have recently overdosed on opioids. In this article, the research, planning, building, and implementation of an opioid treatment center composed of an admission and triage unit, inpatient withdrawal management unit, and inpatient residential unit are described. A multi-agency and multi-disciplinary approach were used to immediately engage patients and connect them to treatment for opioid addiction. FINDINGS: Implementation of a collaborative model of care offers patients who overdose on opioids with immediate access to admission for treatment. This has resulted in significantly higher numbers of patients seeking and staying in treatment. CONCLUSIONS: Through multi-agency collaboration and a shared commitment to addressing the challenges of the opioid epidemic in innovative ways, more patients who are struggling with addiction have increased opportunities to engage in treatment and move towards recovery. CLINICAL RELEVANCE: Clinicians, first responders, and communities can employ MASC principles to guide their approaches to serve patients who have recently overdosed on opioids or who are in active addiction.


Assuntos
Modelos Organizacionais , Overdose de Opiáceos/terapia , Transtornos Relacionados ao Uso de Opioides/terapia , Centros de Tratamento de Abuso de Substâncias/organização & administração , Adolescente , Adulto , Idoso , Comportamento Cooperativo , Empatia , Feminino , Humanos , Relações Interinstitucionais , Masculino , Pessoa de Meia-Idade , Ohio/epidemiologia , Overdose de Opiáceos/epidemiologia , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Respeito , Adulto Jovem
10.
Phys Rev Lett ; 117(27): 275301, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-28084759

RESUMO

We demonstrate a new way to extend the coherence time of separated Bose-Einstein condensates that involves immersion into a superfluid bath. When both the system and the bath have similar scattering lengths, immersion in a superfluid bath cancels out inhomogeneous potentials either imposed by external fields or inherent in density fluctuations due to atomic shot noise. This effect, which we call superfluid shielding, allows for coherence lifetimes beyond the projection noise limit. We probe the coherence between separated condensates in different sites of an optical lattice by monitoring the contrast and decay of Bloch oscillations. Our technique demonstrates a new way that interactions can improve the performance of quantum devices.

12.
Eye Contact Lens ; 41(1): 12-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25536529

RESUMO

OBJECTIVE: To examine current practice patterns in the management of bacterial keratitis among U.S. ophthalmologists and differences in the management and opinions between cornea specialists and non-cornea specialists. METHODS: A questionnaire was distributed to randomly selected ophthalmologists in July 2011 using an online survey system. It inquired about the number of patients with corneal ulcers seen monthly, frequency of Gram staining and culturing corneal ulcers, maintenance of diagnostic supplies, opinions on when culturing is necessary for corneal ulcers, treatment preferences for different severities of bacterial corneal ulcers, and opinions regarding relative efficacy of fourth-generation fluoroquinolones and fortified broad-spectrum antibiotics. RESULTS: One thousand seven hundred one surveys were distributed, and 486 (28.6%) surveys were returned. A minority of corneal ulcers was Gram stained (23.7%±34.1%, mean±SD) or cultured (35.1%±38.0%), but cornea specialists were more likely to perform both. The most popular antibiotic for the treatment of less severe ulcers was moxifloxacin (55.4%), and the most popular treatment of more severe ulcers was fortified broad-spectrum antibiotics (62.7%). Cornea specialists were significantly more likely than non-cornea specialists to prescribe fortified antibiotics for more severe corneal ulcers (78.1% vs. 53.7%, P<0.0001). A greater number of cornea specialists stated that fourth-generation fluoroquinolones were less effective than fortified antibiotics for the treatment of more severe corneal ulcers (79.6% of cornea specialists vs. 60.9% of non-cornea specialists, P<0.001). CONCLUSIONS: Cornea specialists and non-cornea specialists manage bacterial keratitis differently, with cornea specialists more likely to perform diagnostic testing and prescribe fortified broad-spectrum antibiotics for severe bacterial keratitis. Additional prospective studies demonstrating visual outcomes after differential treatment of bacterial keratitis are needed.


Assuntos
Antibacterianos/uso terapêutico , Úlcera da Córnea , Infecções Oculares Bacterianas , Padrões de Prática Médica , Adulto , Atitude do Pessoal de Saúde , Técnicas Bacteriológicas , Serviços de Saúde Comunitária , Úlcera da Córnea/diagnóstico , Úlcera da Córnea/tratamento farmacológico , Quimioterapia Combinada , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/tratamento farmacológico , Feminino , Fluoroquinolonas/uso terapêutico , Humanos , Pessoa de Meia-Idade , Soluções Oftálmicas/uso terapêutico , Estudos Prospectivos , Inquéritos e Questionários , Estados Unidos
13.
BMC Med Educ ; 15: 141, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26311538

RESUMO

BACKGROUND: The demands placed on medical trainees pose a challenge to personal wellbeing, leading to burnout and erosion of empathy. However, it is unclear at what point in medical education this decline begins. Although many schools have begun to design and implement wellness programs for their students, the medical education community's experience in evaluating their impact is limited. METHODS: The authors designed a wellness needs assessment of all medical students at the Albert Einstein College of Medicine in order to assess students' health behaviors, stress and depressive symptoms. The online survey was administered to all medical students from the classes of 2014 and 2015 at the beginning of their first year of medical school and again at the end of their third year. Chi-square and T-tests were run comparing the survey responses of the two classes. RESULTS: There was a significant increase in perceived stress from an average of 5.51 in the first year to 6.49 in the third year (p = .0001). The number of students at risk for depression, defined as a CES-D score greater than 16, was 94 (28.4%) in the first year and 131 (39.0%) in their third year (p = .004). CONCLUSIONS: This study demonstrates a significant increase in the proportion of students at risk for depression in their third year as compared to the first year as well as an increase in perceived stress. In response to these findings, the authors took a multi-disciplinary approach in the development of a comprehensive program to address student wellness, including efforts to address issues specific to the clinical clerkships. This program is unique in that its design, inception and ongoing evaluation have taken the needs of an entire medical school class into account.


Assuntos
Depressão/epidemiologia , Estresse Psicológico/epidemiologia , Estudantes de Medicina/psicologia , Humanos , Cidade de Nova Iorque/epidemiologia , Fatores de Risco , Faculdades de Medicina/estatística & dados numéricos , Estudantes de Medicina/estatística & dados numéricos , Inquéritos e Questionários
14.
J Comput Assist Tomogr ; 38(1): 53-60, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24378891

RESUMO

OBJECTIVE: To evaluate qualitative and simple quantitative measures of all 4 cardiac chamber sizes on computed tomography (CT) in comparison with transthoracic echocardiography (TTE). METHODS: We retrospectively identified 104 adults with electrocardiographically gated cardiac CT and TTE within 3 months. Axial early diastolic (75% R-R) CT images were reviewed for qualitative chamber enlargement, and each chamber was measured linearly. Transthoracic echocardiography was reviewed for linear, area, and volume measurements. Interrater agreement was calculated using Cohen κ and Pearson correlation. RESULTS: There were significant correlations between linear left atrium and left ventricle sizes by CT and TTE (r = 0.686 and r = 0.709, respectively). Correlations for right atrium and right ventricle measurements were lower (r = 0.447 and r = 0.492, respectively). Agreement between CT and TTE for qualitative chamber enlargement was poor (highest κ = 0.35). Computed tomography sensitivity was ≤ 62% for enlargement of all chambers. CONCLUSIONS: Linear CT measurements of left-sided chamber sizes correlate well with TTE. Right heart measurements and qualitative assessments agreed poorly with TTE.


Assuntos
Ecocardiografia/métodos , Átrios do Coração/anatomia & histologia , Ventrículos do Coração/anatomia & histologia , Tomografia Computadorizada por Raios X/métodos , Técnicas de Imagem de Sincronização Cardíaca , Meios de Contraste , Feminino , Átrios do Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ácidos Tri-Iodobenzoicos
15.
J Relig Health ; 53(4): 1249-56, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24609783

RESUMO

Social sciences view spirituality and religion separately; medicine views them together. We identified distinctions regarding clinical practice and teaching among clinician educators based on their self-identified spirituality versus religiosity. We emailed a 24-item survey on spiritual/religious (S/R) issues to clinician educators (n = 1067) at our institution. Three summary scales were created. Responses to statements, 'I consider myself to be spiritual' and 'I consider myself to be religious' generated four comparison groups: 'spiritual only,' 'religious only,' 'both spiritual and religious' and 'neither.' Analyses employed ANOVA and T tests. A total of 633 (59%) surveys were completed. Four percentage self-identified as 'religious only'; remaining respondents divided evenly, about 30% into each of the other categories. Groups differed from one another on all summary scales (p < .0001). Using T tests, the 'spiritual only' group differed from the 'religious only' group regarding teaching. The 'spiritual and religious' group had the highest mean ratings for all summary scales. The 'neither' and 'religious only' group had the lowest mean ratings. Clinicians' spiritual versus religious identity is associated with differences in behavior/attitudes regarding S/R toward clinical practice and medical student teaching. These findings elucidate opportunities for faculty development to explore effects of beliefs on behavior and attitudes within this realm.


Assuntos
Atitude do Pessoal de Saúde , Educação Médica , Identificação Psicológica , Religião e Medicina , Espiritualidade , Análise de Variância , Feminino , Humanos , Masculino , Inquéritos e Questionários
16.
J Biomech ; 166: 112066, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38574563

RESUMO

Precise measurement of joint-level motion from stereo-radiography facilitates understanding of human movement. Conventional procedures for kinematic tracking require significant manual effort and are time intensive. The current work introduces a method for fully automatic tracking of native knee kinematics from stereo-radiography sequences. The framework consists of three computational steps. First, biplanar radiograph frames are annotated with segmentation maps and key points using a convolutional neural network. Next, initial bone pose estimates are acquired by solving a polynomial optimization problem constructed from annotated key points and anatomic landmarks from digitized models. A semidefinite relaxation is formulated to realize the global minimum of the non-convex problem. Pose estimates are then refined by registering computed tomography-based digitally reconstructed radiographs to masked radiographs. A novel rendering method is also introduced which enables generating digitally reconstructed radiographs from computed tomography scans with inconsistent slice widths. The automatic tracking framework was evaluated with stereo-radiography trials manually tracked with model-image registration, and with frames which capture a synthetic leg phantom. The tracking method produced pose estimates which were consistently similar to manually tracked values; and demonstrated pose errors below 1.0 degree or millimeter for all femur and tibia degrees of freedom in phantom trials. Results indicate the described framework may benefit orthopaedics and biomechanics applications through acceleration of kinematic tracking.


Assuntos
Articulação do Joelho , Joelho , Humanos , Fenômenos Biomecânicos , Radiografia , Articulação do Joelho/diagnóstico por imagem , Joelho/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imageamento Tridimensional/métodos
17.
Ann Biomed Eng ; 52(6): 1591-1603, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38558356

RESUMO

Kinematic tracking of native anatomy from stereo-radiography provides a quantitative basis for evaluating human movement. Conventional tracking procedures require significant manual effort and call for acquisition and annotation of subject-specific volumetric medical images. The current work introduces a framework for fully automatic tracking of native knee anatomy from dynamic stereo-radiography which forgoes reliance on volumetric scans. The method consists of three computational steps. First, captured radiographs are annotated with segmentation maps and anatomic landmarks using a convolutional neural network. Next, a non-convex polynomial optimization problem formulated from annotated landmarks is solved to acquire preliminary anatomy and pose estimates. Finally, a global optimization routine is performed for concurrent refinement of anatomy and pose. An objective function is maximized which quantifies similarities between masked radiographs and digitally reconstructed radiographs produced from statistical shape and intensity models. The proposed framework was evaluated against manually tracked trials comprising dynamic activities, and additional frames capturing a static knee phantom. Experiments revealed anatomic surface errors routinely below 1.0 mm in both evaluation cohorts. Median absolute errors of individual bone pose estimates were below 1.0 ∘ or mm for 15 out of 18 degrees of freedom in both evaluation cohorts. Results indicate that accurate pose estimation of native anatomy from stereo-radiography may be performed with significantly reduced manual effort, and without reliance on volumetric scans.


Assuntos
Joelho , Humanos , Joelho/diagnóstico por imagem , Joelho/anatomia & histologia , Joelho/fisiologia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/fisiologia , Imagens de Fantasmas , Radiografia , Modelos Estatísticos
18.
Phys Rev Lett ; 111(18): 185302, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24237531

RESUMO

We experimentally implement the Harper Hamiltonian for neutral particles in optical lattices using laser-assisted tunneling and a potential energy gradient provided by gravity or magnetic field gradients. This Hamiltonian describes the motion of charged particles in strong magnetic fields. Laser-assisted tunneling processes are characterized by studying the expansion of the atoms in the lattice. The band structure of this Hamiltonian should display Hofstadter's butterfly. For fermions, this scheme should realize the quantum Hall effect and chiral edge states.

19.
Phys Rev Lett ; 111(22): 225301, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24329453

RESUMO

We propose a scheme which realizes spin-orbit coupling and the quantum spin Hall effect for neutral atoms in optical lattices without relying on near resonant laser light to couple different spin states. The spin-orbit coupling is created by modifying the motion of atoms in a spin-dependent way by laser recoil. The spin selectivity is provided by Zeeman shifts created with a magnetic field gradient. Alternatively, a quantum spin Hall Hamiltonian can be created by all-optical means using a period-tripling, spin-dependent superlattice.

20.
Int J Comput Assist Radiol Surg ; 18(12): 2125-2142, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37120481

RESUMO

PURPOSE: Multiple applications in open surgical environments may benefit from adoption of markerless computer vision depending on associated speed and accuracy requirements. The current work evaluates vision models for 6-degree of freedom pose estimation of surgical instruments in RGB scenes. Potential use cases are discussed based on observed performance. METHODS: Convolutional neural nets were developed with simulated training data for 6-degree of freedom pose estimation of a representative surgical instrument in RGB scenes. Trained models were evaluated with simulated and real-world scenes. Real-world scenes were produced by using a robotic manipulator to procedurally generate a wide range of object poses. RESULTS: CNNs trained in simulation transferred to real-world evaluation scenes with a mild decrease in pose accuracy. Model performance was sensitive to input image resolution and orientation prediction format. The model with highest accuracy demonstrated mean in-plane translation error of 13 mm and mean long axis orientation error of 5[Formula: see text] in simulated evaluation scenes. Similar errors of 29 mm and 8[Formula: see text] were observed in real-world scenes. CONCLUSION: 6-DoF pose estimators can predict object pose in RGB scenes with real-time inference speed. Observed pose accuracy suggests that applications such as coarse-grained guidance, surgical skill evaluation, or instrument tracking for tray optimization may benefit from markerless pose estimation.


Assuntos
Robótica , Treinamento por Simulação , Cirurgia Assistida por Computador , Humanos , Cirurgia Assistida por Computador/métodos , Instrumentos Cirúrgicos , Simulação por Computador
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