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1.
Opt Express ; 32(9): 15115-15125, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859170

RESUMEN

The rapid advancement of portable electronics has created enormous demand for compact optical imaging systems. Such systems often require folded optical systems with beam steering and shaping components to reduce sizes and minimize image aberration at the same time. In this study, we present a solution that utilizes an inverse-designed dielectric metasurface for arbitrary-angle image-relay with aberration correction. The metasurface phase response is optimized by a series of artificial neural networks to compensate for the severe aberrations in the deflected images and meet the requirements for device fabrication at the same time. We compare our results to the solutions found by the global optimization tool in Zemax OpticStudio and show that the proposed method can predict better point-spread functions and images with less distortion. Finally, we designed a metasurface to achieve the optimized phase profile.

2.
Nanoscale ; 16(9): 4703-4709, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38268454

RESUMEN

Dark-field microscopy (DFM) is a powerful label-free and high-contrast imaging technique due to its ability to reveal features of transparent specimens with inhomogeneities. However, owing to the Abbe's diffraction limit, fine structures at sub-wavelength scale are difficult to resolve. In this work, we report a single image super resolution DFM scheme using a convolutional neural network (CNN). A U-net based CNN is trained with a dataset which is numerically simulated based on the forward physical model of the DFM. The forward physical model described by the parameters of the imaging setup connects the object ground truths and dark field images. With the trained network, we demonstrate super resolution dark field imaging of various test samples with twice resolution improvement. Our technique illustrates a promising deep learning approach to double the resolution of DFM without any hardware modification.

3.
Opt Express ; 31(5): 8714-8724, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36859981

RESUMEN

Structured illumination microscopy (SIM) is a popular super-resolution imaging technique that can achieve resolution improvements of 2× and greater depending on the illumination patterns used. Traditionally, images are reconstructed using the linear SIM reconstruction algorithm. However, this algorithm has hand-tuned parameters which can often lead to artifacts, and it cannot be used with more complex illumination patterns. Recently, deep neural networks have been used for SIM reconstruction, yet they require training sets that are difficult to capture experimentally. We demonstrate that we can combine a deep neural network with the forward model of the structured illumination process to reconstruct sub-diffraction images without training data. The resulting physics-informed neural network (PINN) can be optimized on a single set of diffraction-limited sub-images and thus does not require any training set. We show, with simulated and experimental data, that this PINN can be applied to a wide variety of SIM illumination methods by simply changing the known illumination patterns used in the loss function and can achieve resolution improvements that match theoretical expectations.

4.
J Surg Res ; 283: 1033-1037, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36914993

RESUMEN

INTRODUCTION: Early water seal following minimally invasive pulmonary lobectomy has been shown to reduce chest tube duration and postoperative length of stay (LOS). We evaluated chest tube duration and postoperative LOS following a standardized chest tube management protocol change (water seal on postoperative day 1) after video-assisted thoracic surgery (VATS) pleurodesis. METHODS: We identified adult patients undergoing VATS pleurodesis from August 2013 to December 2021. The chest tube protocol was changed in January 2017 such that patients were placed to water seal on the morning of postoperative day 1. Patients were divided into two groups, before the change (Group 1: August 2013-December 2016) and after (Group 2: January 2017-December 2021). We compared demographics, clinical characteristics, operative details, postoperative chest tube duration and output, and postoperative LOS between the groups. Descriptive statistics and log-transformed multivariable linear regression models were used to identify differences in patient outcomes that were associated with the protocol change. RESULTS: A total of 488 patients underwent VATS pleurodesis during the study period (Group 1: 329 patients; Group 2: 159 patients). The median age was 61 y (interquartile range [IQR] 49-68), 51% were females, 69% were White, and 29% were Black. For postoperative LOS, Group 1 had an IQR of 3-7 d, while Group 2 had an IQR of 2-6 d (P < 0.001). The multivariable log-transformed linear regression models demonstrated that the practice change was associated with reduced chest tube duration (0.77 times the chest tube duration before the change; P < 0.001) and reduced LOS (0.81 times the LOS before the change; P = 0.006). There was an associated reduction in patients needing to return to the operating room (P = 0.048) and needing postoperative extended ventilatory support (P = 0.035). CONCLUSIONS: Development of a standardized protocol to water seal chest tubes on postoperative day 1 following VATS pleurodesis is associated with reduced chest tube duration and LOS without an increase in postoperative complication rates.


Asunto(s)
Tubos Torácicos , Pleurodesia , Adulto , Femenino , Humanos , Persona de Mediana Edad , Masculino , Tubos Torácicos/efectos adversos , Pleurodesia/métodos , Cirugía Torácica Asistida por Video/efectos adversos , Cirugía Torácica Asistida por Video/métodos , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Drenaje/métodos , Resultado del Tratamiento
5.
Laser Photon Rev ; 17(12)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38883699

RESUMEN

Label-free super-resolution (LFSR) imaging relies on light-scattering processes in nanoscale objects without a need for fluorescent (FL) staining required in super-resolved FL microscopy. The objectives of this Roadmap are to present a comprehensive vision of the developments, the state-of-the-art in this field, and to discuss the resolution boundaries and hurdles which need to be overcome to break the classical diffraction limit of the LFSR imaging. The scope of this Roadmap spans from the advanced interference detection techniques, where the diffraction-limited lateral resolution is combined with unsurpassed axial and temporal resolution, to techniques with true lateral super-resolution capability which are based on understanding resolution as an information science problem, on using novel structured illumination, near-field scanning, and nonlinear optics approaches, and on designing superlenses based on nanoplasmonics, metamaterials, transformation optics, and microsphere-assisted approaches. To this end, this Roadmap brings under the same umbrella researchers from the physics and biomedical optics communities in which such studies have often been developing separately. The ultimate intent of this paper is to create a vision for the current and future developments of LFSR imaging based on its physical mechanisms and to create a great opening for the series of articles in this field.

6.
J Robot Surg ; 16(3): 695-703, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34406630

RESUMEN

Evidence supporting the safe use of the single-port (SP) robot for partial nephrectomy is scarce. The purpose of this study was to compare perioperative outcomes for patients undergoing robotic assisted SP vs multi-port (MP) partial nephrectomy (PN) in a time-matched cohort. All patients with clinically localized renal masses who underwent robotic PN from January 2019 to March 2020 were evaluated. Patients were stratified according to SP vs MP approach. Postoperative analgesia was administered in accordance with department-wide opioid stewardship protocol and outpatient opioid use was tracked. Total of 78 patients underwent robotic PN with 26 patients in the SP cohort. The majority of renal masses had low-complexity (53, 67.9%) R.E.N.A.L. nephrometry scores, without a significant difference between the two cohorts (p = 0.19). A retroperitoneal approach was performed in 16 (20.5%) patients overall, though more commonly via the SP robotic approach (13 vs 3, p < 0.001). Mean operative time for SP cases was 183.9 ± 63.5 min vs 208.6 ± 65.0 min in the MP cohort (p = 0.12). Rate of conversion to radical nephrectomy was 3.8% vs 9.6% for SP vs MP cases, respectively, (p = 0.37). The majority of patients were discharged on postoperative day one (67.9%) irrespective of operative approach (p = 0.60). There were no differences in inpatient milligram morphine equivalents administered (MME, p = 0.08) or outpatient postoperative MME prescribed (p = 0.21) between the two cohorts. In this retrospective single-institution study, SP robotic approach offers similar short-term perioperative outcomes to MP platforms for minimally invasive, nephron-sparing surgery. Using the SP system was not associated with a reduction in postoperative opioid analgesic requirements.


Asunto(s)
Neoplasias Renales , Procedimientos Quirúrgicos Robotizados , Robótica , Analgésicos Opioides/uso terapéutico , Humanos , Neoplasias Renales/cirugía , Nefrectomía/métodos , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/métodos , Resultado del Tratamiento
7.
Artículo en Inglés | MEDLINE | ID: mdl-34886348

RESUMEN

The COVID-19 pandemic has left many individuals suffering from "connection deficit disorder" given changes to the way we work, go to school, socialize, and engage in daily activities. Young adults affected by cancer between the ages of 18-39 have known this connection deficit long before the pandemic. Being diagnosed and treated for cancer during this time can significantly disrupt engagement in important educational, career, social, and reproductive pursuits, and contribute to increased stress, anxiety, depression, and other negative outcomes. Experiencing meaningful connection-with nature, with peers who understand, and with oneself, may help assuage this adverse effect of disconnect. A single arm within-subjects program evaluation was conducted to examine outcomes following participation in immersive, multi-night, mindfulness-based treks in nature in a sample of young adults (n = 157) and caregivers (n = 50) affected by cancer from 2016-2021. Pre to post-trek changes included significant (p < 0.001) self-reported improvements in feeling connected to nature (d = 0.93-0.95), peers (d = 1.1-1.3), and oneself (d = 0.57-1.5); significant (p < 0.001) improvements on PROMIS Anxiety (d = 0.62-0.78), Depression (d = 0.87-0.89), and Sleep Disturbance (d = 0.37-0.48) short forms; and significant (p < 0.05) changes in pro-inflammatory biomarkers (d = 0.55-0.82). Connection-promoting experiences like this have the potential to improve health and wellbeing in this population and serve as a model for others.


Asunto(s)
COVID-19 , Atención Plena , Neoplasias , Adolescente , Adulto , Cuidadores , Humanos , Neoplasias/terapia , Pandemias , Evaluación de Programas y Proyectos de Salud , SARS-CoV-2 , Adulto Joven
8.
Can J Urol ; 28(5): 10817-10823, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34657654

RESUMEN

INTRODUCTION: We aim to investigate if the addition of MRI-US fusion biopsy (FB) can aid in radiation planning and alter the boost field in cases of stereotactic body radiation therapy (SBRT) for prostate cancer with a simultaneous integrated boost (SIB) to a magnetic resonance imaging (MRI)-defined intraprostatic lesion. MATERIALS AND METHODS: Patients undergoing SBRT with SIB for biopsy-proven prostatic adenocarcinoma and a pre-radiation MRI were retrospectively reviewed. 36.25 Gy in 5 fractions was delivered to entire prostate along with SIB of 40 Gy to an MRI-defined intraprostatic lesion. Demographic, radiation planning details, and post-procedural outcomes were compared between patients undergoing systematic transrectal ultrasound (TRUS) biopsy followed by MRI to those undergoing an MRI followed by a FB prior to radiation planning. RESULTS: Forty-three patients underwent systematic TRUS biopsy followed by MRI and 46 patients underwent FB prior to radiation planning. Patients undergoing systematic TRUS biopsy had a smaller prostate volume when compared to the FB cohort (37.58 ± 13.78 versus 50.28 ± 26.76 cc, p = 0.007). No differences in prostate planning target volume (PTVprostate) and boost volume (PTVboost) were noted, but those undergoing TRUS biopsy prior to MRI had a higher integrated boost volume density (IBVD = PTVboost/total prostate volume) (0.16 ± 0.09 versus 0.13 ± 0.06, p = 0.045). No differences were observed in genitourinary or gastrointestinal toxicity rates. CONCLUSIONS: Compared to systematic TRUS biopsy, implementation of prebiopsy prostate MRI and FB allows for safe and feasible SBRT in patients with significantly larger prostate volumes without increasing SIB cancer-directed treatment volumes, oncologic outcomes, quality of life measures, or treatment-related toxicities.


Asunto(s)
Neoplasias de la Próstata , Radiocirugia , Humanos , Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/radioterapia , Calidad de Vida , Radiocirugia/efectos adversos , Estudios Retrospectivos
10.
Nat Commun ; 12(1): 1559, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692354

RESUMEN

Structured illumination microscopy (SIM) is one of the most powerful and versatile optical super-resolution techniques. Compared with other super-resolution methods, SIM has shown its unique advantages in wide-field imaging with high temporal resolution and low photon damage. However, traditional SIM only has about 2 times spatial resolution improvement compared to the diffraction limit. In this work, we propose and experimentally demonstrate an easily-implemented, low-cost method to extend the resolution of SIM, named speckle metamaterial-assisted illumination nanoscopy (speckle-MAIN). A metamaterial structure is introduced to generate speckle-like sub-diffraction-limit illumination patterns in the near field with improved spatial frequency. Such patterns, similar to traditional SIM, are then used to excite objects on top of the surface. We demonstrate that speckle-MAIN can bring the resolution down to 40 nm and beyond. Speckle-MAIN represents a new route for super-resolution, which may lead to important applications in bio-imaging and surface characterization.


Asunto(s)
Microscopía/métodos , Imagenología Tridimensional/métodos , Microscopía Fluorescente/métodos
11.
J Surg Res ; 258: 224-230, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33032141

RESUMEN

BACKGROUND: Understanding the differences between articles that amass a high number of citations and those that receive very few allows investigators to write journal articles that maximize the impact of their research. There are minimal data regarding these two cohorts in the cardiothoracic surgery literature. METHODS: We identified all primary research articles from 1998 to 2008 from The Journal of Thoracic and Cardiovascular Surgery, The Journal of Cardiac Surgery, The Annals of Thoracic Surgery, and The European Journal of Cardio-Thoracic Surgery (n = 4276). Eighty-seven of these articles accrued 0 or only 1 citation within 10 y of publication. We compared this "low citation" cohort to the "high citation" cohort made up of the 87 highest-cited articles from the same journals over the same time period. RESULTS: When compared with the low-citation articles, high-citation articles were significantly more likely to be clinical in nature (P < 0.0001), have observational study design (P < 0.0001), involve multidisciplinary authorship (P < 0.0001), and have more funding reported (P = 0.0039). With regard to technical aspects of the article, the high-citation articles were likely to have longer titles (P = 0.0086), punctuation in the title (P = 0.0027), longer abstracts (P = 0.0007), more words in the manuscript (P < 0.0001), more authors (P < 0.0001), more declared conflict of interests (P = 0.0167), more references (P < 0.0001), more tables (P < 0.0001), more figures (P = 0.0024), and more pages (P < 0.0001). There was no significant difference in the year of publication among both cohorts. CONCLUSIONS: This review suggests that there are several important distinguishing characteristics that should be considered by investigators when designing and implementing cardiothoracic research studies to maximize the impact of their published research.


Asunto(s)
Bibliometría , Cirugía Torácica
12.
Ann Thorac Surg ; 112(3): 961-967, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33127402

RESUMEN

BACKGROUND: Although the overall gender gap in medicine is narrowing, significant gender disparities remain in the cardiothoracic surgery (CTS) field; women represent only 7% of practicing surgeons and 20% of residents. The purpose of this study was to identify gender differences in CTS exposure and interest among fourth year medical students applying to general surgery residency. METHODS: An anonymous survey was emailed to general surgery residency applicants at a major academic program for the 2019 and 2020 application cycles. Data were stratified by gender and analyzed using the χ2 and t tests. RESULTS: Of the 303 responders to the survey, 44% were women. A total of 58% of women were unlikely to be interested in or were definitely not interested in pursuing a career in CTS compared with 35% of men (P < .05). Men were 2.5 times more likely than women to be interested in CTS (odds ratio, 2.5; 95% confidence interval, 1.5 to 4.1). More men had rotated through CTS (55% vs 44%; P = .04) and shadowed a cardiothoracic surgeon (41% vs 29%; P = .03). More than 30% of women interested in CTS reported mentorship as the most important factor in their decision. Mentorship and CTS rotations were both independently associated with CTS interest after adjusting for gender. CONCLUSIONS: Interest in CTS is disappointingly low among women and represents a troublesome disparity that must be addressed. Early exposure to CTS and more mentorship from cardiothoracic surgeons are critical to reverse the current trend. Further studies are necessary to determine factors limiting female exposure to CTS rotations and dissuading female applicants from pursuing careers in CTS.


Asunto(s)
Selección de Profesión , Internado y Residencia , Cirugía Torácica/educación , Adulto , Femenino , Humanos , Masculino , Distribución por Sexo
13.
Urology ; 146: 252, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33272432
14.
Urology ; 146: 248-252, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32961223

RESUMEN

OBJECTIVE: To report our initial experience with ureteral appendiceal interposition (UAI) in a series of adult patients undergoing ureteral reconstruction for ureteral stricture. METHODS: We retrospectively collected data of patients who underwent UAI for ureteral stricture disease from December 2015 to March of 2020. Success of surgery was defined as one that required no subsequent procedural intervention for recurrent ureteral stricture disease, or loss of kidney function. RESULTS: Eleven patients underwent UAI for ureteral stricture. Etiologies for stricture disease included radiation exposure, nephrolithiasis, and iatrogenic injury. Median follow-up was 363 days. Three patients had Clavien-Dindo class III complications during their hospitalization. No patient required repeat intervention due to recurrent ureteral stricture disease. On imaging, 9 patients had no obstruction on Lasix renal scan postoperatively, or improvement in hydronephrosis on CT scan. Two patients with poor renal function preop continued to show poor function after surgery. CONCLUSION: The use of the appendix is a safe and feasible option for ureteral reconstruction in appropriately selected adult patients when primary ureteral repair is not possible.


Asunto(s)
Apéndice/cirugía , Obstrucción Ureteral/cirugía , Adulto , Anciano , Constricción Patológica/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Uréter/cirugía , Procedimientos Quirúrgicos Urológicos/métodos
15.
Curr Opin Urol ; 30(2): 171-176, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31895888

RESUMEN

PURPOSE OF REVIEW: The review of potential therapies in the treatment of hyperoxaluria is timely, given the current excitement with clinical trials and the mounting evidence of the importance of oxalate in both kidney stone and chronic kidney disease. RECENT FINDINGS: Given the significant contribution of both endogenous and dietary oxalate to urinary oxalate excretions, it is not surprising therapeutic targets are being studied in both pathways. This article covers the existing data on endogenous and dietary oxalate and the current targets in these pathways. SUMMARY: In the near future, there will likely be therapies targeting both endogenous and dietary oxalate, especially in subsets of kidney stone formers.


Asunto(s)
Hiperoxaluria/metabolismo , Hiperoxaluria/terapia , Oxalatos/efectos adversos , Oxalatos/metabolismo , Adulto , Animales , Dieta/efectos adversos , Humanos , Hiperoxaluria/etiología , Cálculos Renales/química , Cálculos Renales/etiología , Cálculos Renales/metabolismo , Cálculos Renales/terapia , Ratones , Ratas , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/terapia
16.
Biomolecules ; 9(9)2019 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-31487821

RESUMEN

The world of medicinal therapies has been historically, and remains to be, dominated by the use of elegant organic molecular structures. Now, a novel medical treatment is emerging based on CeO2 nano-crystals that are discrete clusters of a few hundred atoms. This development is generating a great deal of exciting and promising research activity, as evidenced by this Special Issue of Biomolecules. In this paper, we provide both a steady-state and time-dependent mathematical description of a sequence of reactions: superoxide generation, superoxide dismutase, and hydrogen peroxide catalase and ceria regeneration. This sequence describes the reactive oxygen species (ROS); superoxide, O2-, molecular oxygen, O2, hydroxide ion OH- and hydrogen peroxide, H2O2, interacting with the Ce3+, and Ce4+ surface cations of nanoparticle ceria, CeO2. Particular emphasis is placed on the predicted time-dependent role of the Ce3+/Ce4+ ratio within the crystal. The net reaction is succinctly described as: H2O2 + 2O2- + 2H+ → 2H2O + 2O2. The chemical equations and mathematical treatment appears to align well with several critical in vivo observations such as; direct and specific superoxide dismutase (SOD), ROS control, catalytic regeneration, ceria self-regulation and self-limiting behavior. However, in contrast to experimental observations, the model predicts that the 4+ ceric ion state is the key SOD agent. Future work is suggested based on these calculations.


Asunto(s)
Cerio/química , Modelos Químicos , Nanopartículas/química , Especies Reactivas de Oxígeno/química , Humanos , Cinética
17.
Proc Natl Acad Sci U S A ; 113(33): 9250-5, 2016 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-27482091

RESUMEN

To determine the appropriate punishment for a harmful action, people must often make inferences about the transgressor's intent. In courtrooms and popular media, such inferences increasingly rely on video evidence, which is often played in "slow motion." Four experiments (n = 1,610) involving real surveillance footage from a murder or broadcast replays of violent contact in professional football demonstrate that viewing an action in slow motion, compared with regular speed, can cause viewers to perceive an action as more intentional. This slow motion intentionality bias occurred, in part, because slow motion video caused participants to feel like the actor had more time to act, even when they knew how much clock time had actually elapsed. Four additional experiments (n = 2,737) reveal that allowing viewers to see both regular speed and slow motion replay mitigates the bias, but does not eliminate it. We conclude that an empirical understanding of the effect of slow motion on mental state attribution should inform the life-or-death decisions that are currently based on tacit assumptions about the objectivity of human perception.


Asunto(s)
Intención , Juicio , Percepción de Movimiento , Grabación en Video , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Percepción Social , Adulto Joven
18.
J Exp Psychol Gen ; 141(2): 227-32, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21823807

RESUMEN

People's intuitions about the underlying causes of past and future actions might not be the same. In 3 studies, we demonstrate that people judge the same behavior as more intentional when it will be performed in the future than when it has been performed in the past. We found this temporal asymmetry in perceptions of both the strength of an individual's intention and the overall prevalence of intentional behavior in a population. Because of its heightened intentionality, people thought the same transgression deserved more severe punishment when it would occur in the future than when it did occur in the past. The difference in judgments of both intentionality and punishment was partly explained by the stronger emotional reactions that were elicited in response to future actions than in response to past actions. We consider the implications of this temporal asymmetry for legal decision making and theories of attribution more generally.


Asunto(s)
Conducta , Intención , Juicio , Castigo , Juegos Experimentales , Humanos , Principios Morales , Percepción Social , Tiempo
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