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1.
Artículo en Inglés | MEDLINE | ID: mdl-38913725

RESUMEN

In an influential article, Jones et al. (1995) provide evidence that auditory distraction by changing relative to repetitive auditory distracters (the changing-state effect) did not differ between a visual-verbal and visual-spatial serial recall task, providing evidence for an amodal mechanism for the representation of serial order in short-term memory that transcends modalities. This finding has been highly influential for theories of short-term memory and auditory distraction. However, evidence vis-à-vis the robustness of this result is sorely lacking. Here, two high-powered replications of Jones et al.'s (1995) crucial Experiment 4 were undertaken. In the first partial replication (n = 64), a fully within-participants design was adopted, wherein participants undertook both the visual-verbal and visual-spatial serial recall tasks under different irrelevant sound conditions, without a retention period. The second near-identical replication (n = 128), incorporated a retention period and implemented the task-modality manipulation as a between-participants factor, as per the original Jones et al. (1995; Experiment 4) study. In both experiments, the changing-state effect was observed for visual-verbal serial recall but not for visual-spatial serial recall. The results are consistent with modular and interference-based accounts of distraction and challenge some aspects of functional equivalence accounts. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

2.
Opt Lett ; 49(12): 3472-3475, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38875648

RESUMEN

We propose and experimentally demonstrate a dual-wavelength distributed feedback (DFB) laser array utilizing a four-phase-shifted sampled Bragg grating. By using this grating, the coupling coefficient is enhanced by approximately 2.83 times compared to conventional sampled Bragg gratings. The devices exhibit a stable dual-mode lasing achieved by introducing further π-phase shifts at 1/3 and 2/3 positions along the cavity. These devices require only one stage of lithography to define both the ridge waveguide and the gratings, mitigating issues related to misalignment between them. A dual-wavelength laser array has been fabricated with frequency spacings of 320 GHz, 500 GHz, 640 GHz, 800 GHz, and 1 THz. When integrated with semiconductor optical amplifiers, the output power of the device can reach 23.6 mW. Furthermore, the dual-wavelength lasing is maintained across a wide range of injection currents, with a power difference of <3 dB between the two primary modes. A terahertz (THz) signal has been generated through photomixing in a photoconductive antenna, with the measured power reaching 12.8 µW.

3.
Memory ; 32(2): 223-236, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38285521

RESUMEN

The Deese-Roediger and McDermott (DRM) paradigm and visually guided saccade tasks are both prominent research tools in their own right. This study introduces a novel DRM-Saccade paradigm, merging both methodologies. We used rule-based saccadic eye movements whereby participants were presented with items at test and were asked to make a saccade to the left or right of the item to denote a recognition or non-recognition decision. We measured old/new recognition decisions and saccadic latencies. Experiment 1 used a pro/anti saccade task to a single target. We found slower saccadic latencies for correct rejection of critical lures, but no latency difference between correct recognition of studied items and false recognition of critical lures. Experiment 2 used a two-target saccade task and also measured corrective saccades. Findings corroborated those from Experiment 1. Participants adjusted their initial decisions to increase accurate recognition of studied items and rejection of unrelated lures but there were no such corrections for critical lures. We argue that rapid saccades indicate cognitive processing driven by familiarity thresholds. These occur before slower source-monitoring is able to process any conflict. The DRM-Saccade task could effectively track real-time cognitive resource use during recognition decisions.


Asunto(s)
Movimientos Oculares , Movimientos Sacádicos , Humanos , Memoria , Reconocimiento en Psicología , Cognición
4.
Opt Lett ; 48(19): 5093-5096, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37773393

RESUMEN

A dual-wavelength DFB laser array based on four phase-shifted grating and equivalent chirp technology is first proposed, fabricated, and experimentally demonstrated. The dual-wavelength emitting is achieved by symmetrically introducing two π phase shifts into a chirped four phase-shifted sampled grating cavity. Meanwhile, the beating signal of the dual-wavelength output is stabilized by applying an electro-absorption modulator integrated at the rear of the cavity. Under different grating chirp rates, a series of RF signals from 66.8 GHz to 73.6 GHz with a linewidth of less than 210 kHz is obtained.

5.
Opt Lett ; 48(19): 5113-5116, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37773398

RESUMEN

Integrated microring resonator structures based on silicon-on-insulator (SOI) platforms are promising candidates for high-performance on-chip sensing. In this work, a novel sidewall grating slot microring resonator (SG-SMRR) with a compact size (5 µm center radius) based on the SOI platform is proposed and demonstrated experimentally. The experiment results show that the refractive index (RI) sensitivity and the limit of detection value are 620 nm/RIU and 1.4 × 10-4 RIU, respectively. The concentration sensitivity and minimum concentration detection limit are 1120 pm/% and 0.05%, respectively. Moreover, the sidewall grating structure makes this sensor free of free spectral range (FSR) limitation. The detection range is significantly enlarged to 84.5 nm in lab measurement, four times that of the FSR of conventional SMRRs. The measured Q-factor is 3.1 × 103, and the straight slot waveguide transmission loss is 24.2 dB/cm under sensing conditions. These results combined with the small form factor associated with a silicon photonics sensor open up applications where high sensitivity and large measurement range are essential.

6.
Opt Express ; 31(12): 20034-20048, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37381406

RESUMEN

We simulate and demonstrate experimentally an inner-wall grating double slot micro ring resonator (IG-DSMRR) with a center slot ring radius of only 6.72 µm based on the silicon-on-insulator platform. This novel photonic-integrated sensor for optical label-free biochemical analysis boosts the measured refractive index (RI) sensitivity in glucose solutions to 563 nm/RIU with the limit of detection value being 3.7 × 10-6 RIU (refractive index units). The concentration sensitivity for sodium chloride solutions can reach 981 pm/%, with a minimum concentration detection limit of 0.02%. Using the combination of DSMRR and IG, the detection range is enlarged significantly to 72.62 nm, three times the free spectral range of conventional slot micro ring resonators. The measured Q-factor is 1.6 × 104, and the straight strip and double slot waveguide transmission losses are 0.9 dB/cm and 20.2 dB/cm, respectively. This IG-DSMRR combines the advantages of a micro ring resonator, slot waveguide, and angular grating and is highly desirable for biochemical sensing in liquids and gases offering an ultra-high sensitivity and ultra-large measurement range. This is the first report of a fabricated and measured double-slot micro ring resonator with an inner sidewall grating structure.

7.
Biomed Opt Express ; 14(3): 1216-1227, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36950230

RESUMEN

Quantitative detection of virus-like particles under a low concentration is of vital importance for early infection diagnosis and water pollution analysis. In this paper, a novel virus detection method is proposed using indirect polarization parametric imaging method combined with a plasmonic split-ring nanocavity array coated with an Au film and a quantitative algorithm is implemented based on the extended Laplace operator. The attachment of viruses to the split-ring cavity breaks the structural symmetry, and such asymmetry can be enhanced by depositing a thin gold film on the sample, which allows an asymmetrical plasmon mode with a large shift of resonance peak generated under transverse polarization. Correspondingly, the far-field scattering state distribution encoded by the attached virus exhibits a specific asymmetric pattern that is highly correlated to the structural feature of the virus. By utilizing the parametric image sinδ to collect information on the spatial photon state distribution and far-field asymmetry with a sub-wavelength resolution, the appearance of viruses can be detected. To further reduce the background noise and enhance the asymmetric signals, an extended Laplace operator method which divides the detection area into topological units and then calculates the asymmetric parameter is applied, enabling easier determination of virus appearance. Experimental results show that the developed method can provide a detection limit as low as 56 vp/150µL on a large scale, which has great potential in early virus screening and other applications.

8.
Opt Lett ; 48(2): 359-362, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36638457

RESUMEN

We report, to the best of our knowledge, the first demonstration of a 1555-nm stepped-height ridge waveguide polarization mode converter monolithically integrated with a sidewall grating distributed-feedback (DFB) laser using the identical epitaxial layer scheme. The device shows stable single longitudinal mode (SLM) operation with the output light converted from TE to TM polarization with an efficiency of >94% over a wide range of DFB injection currents (IDFB) from 140 mA to 190 mA. The highest TM mode purity of 98.2% was obtained at IDFB = 180 mA. A particular advantage of this device is that only a single step of metalorganic vapor-phase epitaxy and two steps of III-V material dry etching are required for the whole integrated device fabrication, significantly reducing complexity and cost.

9.
J Orthop Res ; 41(3): 546-554, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35672888

RESUMEN

Articular fracture malreduction increases posttraumatic osteoarthritis (PTOA) risk by elevating joint contact stress. A new biomechanical guidance system (BGS) that provides intraoperative assessment of articular fracture reduction and joint contact stress based solely on a preoperative computed tomography (CT) and intraoperative fluoroscopy may facilitate better fracture reduction. The objective of this proof-of-concept cadaveric study was to test this premise while characterizing BGS performance. Articular tibia plafond fractures were created in five cadaveric ankles. CT scans were obtained to provide digital models. Indirect reduction was performed in a simulated operating room once with and once without BGS guidance. CT scans after fixation provided models of the reduced ankles for assessing reduction accuracy, joint contact stresses, and BGS accuracy. BGS was utilized 4.8 ± 1.3 (mean ± SD) times per procedure, increasing operative time by 10 min (39%), and the number of fluoroscopy images by 31 (17%). Errors in BGS reduction assessment compared to CT-derived models were 0.45 ± 0.57 mm in translation and 2.0 ± 2.5° in rotation. For the four ankles that were successfully reduced and fixed, associated absolute errors in computed mean and maximum contact stress were 0.40 ± 0.40 and 0.96 ± 1.12 MPa, respectively. BGS reduced mean and maximum contact stress by 1.1 and 2.6 MPa, respectively. BGS thus improved the accuracy of articular fracture reduction and significantly reduced contact stress. Statement of Clinical Significance: Malreduction of articular fractures is known to lead to PTOA. The BGS described in this work has potential to improve quality of articular fracture reduction and clinical outcomes for patients with a tibia plafond fracture.


Asunto(s)
Fracturas de Tobillo , Fracturas Intraarticulares , Osteoartritis , Fracturas de la Tibia , Humanos , Tibia , Fracturas de la Tibia/cirugía , Fijación de Fractura/métodos , Articulaciones , Cadáver
10.
Biomed Opt Express ; 13(9): 4621-4636, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36187257

RESUMEN

In biomedical imaging, photoacoustic computed tomography (PACT) has recently gained increased interest as this imaging technique has good optical contrast and depth of acoustic penetration. However, a spinning blur will be introduced during the image reconstruction process due to the limited size of the ultrasonic transducers (UT) and a discontinuous measurement process. In this study, a damping UT and adaptive back-projection co-optimization (CODA) method is developed to improve the lateral spatial resolution of PACT. In our PACT system, a damping aperture UT controls the size of the receiving area, which suppresses image blur at the signal acquisition stage. Then, an innovative adaptive back-projection algorithm is developed, which corrects the undesirable artifacts. The proposed method was evaluated using agar phantom and ex-vivo experiments. The results show that the CODA method can effectively compensate for the spinning blur and eliminate unwanted artifacts in PACT. The proposed method can significantly improve the lateral spatial resolution and image quality of reconstructed images, making it more appealing for wider clinical applications of PACT as a novel, cost-effective modality.

11.
Scand J Psychol ; 63(5): 530-535, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35607836

RESUMEN

As a climate change mitigation strategy, environmentally certified 'green' buildings with low carbon footprints are becoming more prevalent in the world. An interesting psychological question is how people perceive the carbon footprint of these buildings given their spatial distributions in a given community. Here we examine whether regular distribution (i.e., buildings organized in a block) or irregular distribution (i.e., buildings randomly distributed) influences people's perception of the carbon footprint of the communities. We first replicated the negative footprint illusion, the tendency to estimate a lower carbon footprint of a combined group of environmentally certified green buildings and ordinary conventional buildings, than the carbon footprint of the conventional buildings alone. Importantly, we found that irregular distribution of the buildings increased the magnitude of the negative footprint illusion. Potential applied implications for urban planning of green buildings are discussed.


Asunto(s)
Ilusiones , Huella de Carbono , Humanos
12.
Appl Opt ; 61(2): 546-553, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35200896

RESUMEN

The ability to identify virus particles is important for research and clinical applications. Because of the optical diffraction limit, conventional optical microscopes are generally not suitable for virus particle detection, and higher resolution instruments such as transmission electron microscopy (TEM) and scanning electron microscopy (SEM) are required. In this paper, we propose a new method for identifying virus particles based on polarization parametric indirect microscopic imaging (PIMI) and deep learning techniques. By introducing an abrupt change of refractivity at the virus particle using antibody-conjugated gold nanoparticles (AuNPs), the strength of the photon scattering signal can be magnified. After acquiring the PIMI images, a deep learning method was applied to identify discriminating features and classify the virus particles, using electron microscopy (EM) images as the ground truth. Experimental results confirm that gold-virus particles can be identified in PIMI images with a high level of confidence.


Asunto(s)
Aprendizaje Profundo , Nanopartículas del Metal , Oro , Microscopía Electrónica de Transmisión , Virión
13.
Opt Lett ; 47(23): 6237-6240, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37219216

RESUMEN

A four-laser array based on sampled Bragg grating distributed feedback (DFB) lasers in which each sampled period contains four phase-shift sections is proposed, fabricated, and experimentally demonstrated. The wavelength spacing between adjacent lasers is accurately controlled to 0.8 nm ± 0.026 nm and the lasers have single mode suppression ratios larger than 50 dB. Using an integrated semiconductor optical amplifier, the output power can reach 33 mW and the optical linewidth of the DFB lasers can be as narrow as 64 kHz. This laser array uses a ridge waveguide with sidewall gratings and needs only one metalorganic vapor-phase epitaxy (MOVPE) step and one III-V material etching process, simplifying the whole device fabrication process, and meeting the requirements of dense wavelength division multiplexing systems.

14.
J Exp Psychol Learn Mem Cogn ; 48(7): 966-974, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34647788

RESUMEN

Visual-verbal serial recall is disrupted when task-irrelevant background speech has to be ignored. Contrary to previous suggestion, it has recently been shown that the magnitude of disruption may be accentuated by the semantic properties of the irrelevant speech. Sentences ending with unexpected words that did not match the preceding semantic context were more disruptive than sentences ending with expected words. This particular instantiation of a deviation effect has been termed the semantic mismatch effect. To establish a new phenomenon, it is necessary to show that the effect can be independently replicated and does not depend on specific boundary conditions such as the language of the stimulus material. Here we report a preregistered replication of the semantic mismatch effect in which we examined the effect of unexpected words in 4 different languages (English, French, German, and Swedish) across 4 different laboratories. Participants performed a serial recall task while ignoring sentences with expected or unexpected words that were recorded using text-to-speech software. Independent of language, sentences ending with unexpected words were more disruptive than sentences ending with expected words. In line with previous results, there was no evidence of habituation of the semantic mismatch effect in the form of a decrease in disruption with repeated exposure to the occurrence of unexpected words. The successful replication and extension of the effect to different languages indicates the expression of a general and robust mechanism that reacts to violations of expectancies based on the semantic content of the irrelevant speech. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Multilingüismo , Percepción del Habla , Humanos , Lenguaje , Recuerdo Mental , Semántica
15.
J Orthop Trauma ; 36(2): e51-e55, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34050077

RESUMEN

OBJECTIVE: To compare deep infection rate and causative organisms in open fractures of the lower extremity from agricultural trauma with similar injuries in nonagricultural trauma. DESIGN: Retrospective. SETTING: Two tertiary care institutions. METHODS: Open lower extremity fractures sustained between 2003 and 2018 caused by agriculture-related trauma in adult patients were reviewed. A nonagriculture open fracture control group (NAG) was identified for comparison. Patient demographics and injury characteristics were assessed. Outcomes included occurrence of deep infection and causative organisms. RESULTS: One hundred seventy-eight patients were identified in the agriculture (AG) (n = 89) and control (NAG) (n = 89) groups. Among patients with agricultural injury, farm machinery was the most common mechanism in 69 (77.5%) of them. Open injuries of the foot (38.2%) and tibial shaft injuries (25.8%) were the most common in the AG and NAG groups, respectively. Deep infection was seen in 21% of patients in the AG group compared with 10% in the NAG group (P < 0.05). In the AG group, anaerobic infection occurred in 44% of patients with deep infection compared with 9.1% in the NAG group (P < 0.05). The most common anaerobic organisms included enterococci, Pseudomonas aeruginosa, and Clostridium perfringens. CONCLUSIONS: This study supports that open fractures due to agricultural trauma have a high infection rate, with anaerobic infection occurring at higher rates than in injuries due to nonagricultural trauma. Prophylactic treatment with antibiotics directed against anaerobes is indicated in these injuries. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.


Asunto(s)
Fracturas Abiertas , Fracturas de la Tibia , Adulto , Agricultura , Anaerobiosis , Antibacterianos , Fracturas Abiertas/epidemiología , Fracturas Abiertas/cirugía , Humanos , Estudios Retrospectivos , Infección de la Herida Quirúrgica , Resultado del Tratamiento
16.
Front Psychol ; 12: 702398, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34955942

RESUMEN

One of the today's greatest challenges is to adjust our behavior so that we can avoid a major climate disaster. To do so, we must make sacrifices for the sake of the environment. The study reported here investigates how anchors (extrinsic motivational-free information) and normative messages (extrinsic motivational information) influence people's tradeoffs between travel time and carbon dioxide (CO2) emissions in the context of car travel and whether any interactions with environmental concern (an intrinsic motivational factor) can be observed. In this study, people received either a CO2, health or no normative message together with either a high anchor, a low anchor, or no anchor. People that received both a high anchor and a CO2 emission normative message were willing to travel for a longer time than those that only received a high anchor. If a low anchor was presented, no differences in willingness to travel for a longer time were found between the three different conditions of normative message groups, i.e., CO2 normative message, health normative message, or no normative message. People with higher concern for the environment were found to be willing to travel for a longer time than those with lower concern for the environment. Further, this effect was strongest when a high anchor was presented. These results suggest that anchors and normative messages are among the many factors that can influence people's tradeoffs between CO2 emission and travel time, and that various factors may have to be combined to increase their influence over pro-environmental behavior and decisions.

17.
Appl Opt ; 60(8): 2141-2149, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33690308

RESUMEN

Vibrations cause many problems such as displacement, distortion, and defocusing in microscopic imaging systems. Because vibration errors are random in direction, amplitude, and frequency, it is not known which aspect of the image quality will be affected by these problems and to what extent. Polarization parametric indirect microscopic imaging (PIMI) is a technique that records polarization parameters in a conventional wide-field reflection microscope using polarization modulation of the illumination beam and additional data analysis of the raw images. This indirect imaging technique allows the spatial resolution of the system to be improved. Here, the influence of vibration on the image sharpness and spatial resolution of a PIMI system is analyzed theoretically and experimentally. Degradation in the sharpness of PIMI images is quantified by means of the modulation transfer function and deterioration in the effective spatial resolution by the Fourier ring correlation. These results show that the quality of PIMI images can be improved significantly using vibration isolation.

18.
Opt Express ; 29(2): 1221-1231, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33726341

RESUMEN

Optical-matter interactions and photon scattering in a sub-wavelength space are of great interest in many applications, such as nanopore-based gene sequencing and molecule characterization. Previous studies show that spatial distribution features of the scattering photon states are highly sensitive to the dielectric and structural properties of the nanopore array and matter contained on or within them, as a result of the complex optical-matter interaction in a confined system. In this paper, we report a method for shape characterization of subwavelength nanowells using photon state spatial distribution spectra in the scattering near field. Far-field parametric images of the near-field optical scattering from sub-wavelength nanowell arrays on a SiN substrate were obtained experimentally. Finite-difference time-domain simulations were used to interpret the experimental results. The rich features of the parametric images originating from the interaction of the photons and the nanowells were analyzed to recover the size of the nanowells. Experiments on nanoholes modified with Shp2 proteins were also performed. Results show that the scattering distribution of modified nanoholes exhibits significant differences compared to empty nanoholes. This work highlights the potential of utilizing the photon status scattering of nanowells for molecular characterization or other virus detection applications.


Asunto(s)
Microscopía de Polarización/instrumentación , Nanoestructuras/química , Dispersión de Radiación , Compuestos de Silicona/química , Diseño de Equipo , Luz , Fotones
19.
J Exp Psychol Learn Mem Cogn ; 47(7): 1054-1066, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33523694

RESUMEN

Data on orienting and habituation to irrelevant sound can distinguish between task-specific and general accounts of auditory distraction: Distractors either disrupt specific cognitive processes (e.g., Jones, 1993; Salamé & Baddeley, 1982), or remove more general-purpose attentional resources from any attention-demanding task (e.g., Cowan, 1995). Tested here is the prediction that there is no further auditory distraction effect on immediate serial recall with increments in the number of distractors beyond the "changing-state point" of two discrete distractors. A Bayes factor analysis refutes this nil hypothesis: This prediction, a key element of the strong changing-state hypothesis, is shown to be less likely than two competing alternatives. Quantitative predictions for distraction as a function of the number of distracters are derived for an orienting-response (OR) and a stimulus-mismatch (SMM) hypothesis, representing general and task-specific accounts respectively. The data are shown to be more likely under the SMM hypothesis. Prospects for a parametric account of auditory distraction are considered. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Percepción Auditiva , Recuerdo Mental , Atención , Teorema de Bayes , Humanos , Memoria a Corto Plazo
20.
Nanoscale Adv ; 3(24): 6882-6887, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36132363

RESUMEN

A parallel four-quadrant sensing method utilizing a specially designed gold nanodot array is created for sensing virus-like particles with a sub-diffraction limit size (∼100 nm) in a wide-field image. Direct label-free sensing of viruses using multiple four-quadrant sensing channels in parallel in a wide-field view enables the possibility of high-throughput onsite screening of viruses.

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