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1.
Cereb Cortex ; 34(9)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39319441

RESUMEN

The phase synchronization of brain oscillations plays an important role in visual processing, perceptual awareness, and performance. Yet, the cortical mechanisms underlying modulatory effects of post-stimulus phase coherence and frequency-specific oscillations associated with different aspects of vision are still subject to debate. In this study, we aimed to identify the post-stimulus phase coherence of cortical oscillations associated with perceived visibility and contour discrimination. We analyzed electroencephalogram data from two masking experiments where target visibility was manipulated by the contrast ratio or polarity of the mask under various onset timing conditions (stimulus onset asynchronies, SOAs). The behavioral results indicated an SOA-dependent suppression of target visibility due to masking. The time-frequency analyses revealed significant modulations of phase coherence over occipital and parieto-occipital regions. We particularly identified modulations of phase coherence in the (i) 2-5 Hz frequency range, which may reflect feedforward-mediated contour detection and sustained visibility; and (ii) 10-25 Hz frequency range, which may be associated with suppressed visibility through inhibitory interactions between and within synchronized neural pathways. Taken together, our findings provide evidence that oscillatory phase alignments, not only in the pre-stimulus but also in the post-stimulus window, play a crucial role in shaping perceived visibility and dynamic vision.


Asunto(s)
Electroencefalografía , Estimulación Luminosa , Percepción Visual , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Percepción Visual/fisiología , Estimulación Luminosa/métodos , Corteza Cerebral/fisiología , Enmascaramiento Perceptual/fisiología
2.
Prev Med ; 180: 107881, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38286273

RESUMEN

Visual assessment is currently used for primary screening or triage of screen-positive individuals in cervical cancer screening programs. Most guidelines recommend screening and triage up to at least age 65 years old. We examined cervical images from participants in three National Cancer Institute funded cervical cancer screening studies: ALTS (2864 participants recruited between 1996 to 1998) in the United States (US), NHS (7548 in 1993) in Costa Rica, and the Biopsy study (684 between 2009 to 2012) in the US. Specifically, we assessed the visibility of the squamocolumnar junction (SCJ), which is the susceptible zone for precancer/cancer by age, as reported by colposcopist reviewers either at examination or review of cervical images. The visibility of the SCJ declined substantially with age: by the late 40s the majority of people screened had at most partially visible SCJ. On longitudinal analysis, the change in SCJ visibility from visible to not visible was largest for participants from ages 40-44 in ALTS and 50-54 in NHS. Of note, in the Biopsy study, the live colposcopic exam resulted in significantly higher SCJ visibility as compared to review of static images (Weighted kappa 0.27 (95% Confidence Interval: 0.21, 0.33), Asymmetry chi-square P-value<0.001). Lack of SCJ visibility leads to increased difficulty in diagnosis and management of cervical precancers. Therefore, cervical cancer screening programs reliant on visual assessment might consider lowering the upper age limit for screening if there are not adequately trained personnel and equipment to evaluate and manage participants with inadequately visible SCJ.


Asunto(s)
Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Humanos , Anciano , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/patología , Detección Precoz del Cáncer/métodos , Displasia del Cuello del Útero/patología , Biopsia
3.
Conscious Cogn ; 125: 103760, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39305788

RESUMEN

Visual masking and attentional selection play important roles in controlling information processing for perception. Using an experimental design combining metacontrast with attentional load, we investigated the time course of changes in event-related potentials under different attentional load and masking conditions. The behavioral results indicated significant effects of attentional load on masking functions (i.e., masking strength as a function of stimulus onset asynchrony between target and mask). The analyses of neural activities revealed significant effects of masking and attentional load on early components located over occipital and parieto-occipital scalp sites. There were also significant modulations in the late positivity range centered over centro-parietal electrodes. However, the nature of modulations in early and late components was different. These findings overall highlight the diverse nature of masking and attentional influences on visual processing, particularly suggesting that attentional load in the visual field may have distinct effects at different stages of perceptual processing.

4.
Health Care Manag Sci ; 27(2): 188-207, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38689176

RESUMEN

A patient fall is one of the adverse events in an inpatient unit of a hospital that can lead to disability and/or mortality. The medical literature suggests that increased visibility of patients by unit nurses is essential to improve patient monitoring and, in turn, reduce falls. However, such research has been descriptive in nature and does not provide an understanding of the characteristics of an optimal inpatient unit layout from a visibility-standpoint. To fill this gap, we adopt an interdisciplinary approach that combines the human field of view with facility layout design approaches. Specifically, we propose a bi-objective optimization model that jointly determines the optimal (i) location of a nurse in a nursing station and (ii) orientation of a patient's bed in a room for a given layout. The two objectives are maximizing the total visibility of all patients across patient rooms and minimizing inequity in visibility among those patients. We consider three different layout types, L-shaped, I-shaped, and Radial; these shapes exhibit the section of an inpatient unit that a nurse oversees. To estimate visibility, we employ the ray casting algorithm to quantify the visible target in a room when viewed by the nurse from the nursing station. The algorithm considers nurses' horizontal visual field and their depth of vision. Owing to the difficulty in solving the bi-objective model, we also propose a Multi-Objective Particle Swarm Optimization (MOPSO) heuristic to find (near) optimal solutions. Our findings suggest that the Radial layout appears to outperform the other two layouts in terms of the visibility-based objectives. We found that with a Radial layout, there can be an improvement of up to 50% in equity measure compared to an I-shaped layout. Similar improvements were observed when compared to the L-shaped layout as well. Further, the position of the patient's bed plays a role in maximizing the visibility of the patient's room. Insights from our work will enable understanding and quantifying the relationship between a physical layout and the corresponding provider-to-patient visibility to reduce adverse events.


Asunto(s)
Accidentes por Caídas , Algoritmos , Arquitectura y Construcción de Hospitales , Unidades Hospitalarias , Habitaciones de Pacientes , Humanos , Arquitectura y Construcción de Hospitales/métodos , Unidades Hospitalarias/organización & administración , Accidentes por Caídas/prevención & control , Habitaciones de Pacientes/organización & administración , Seguridad del Paciente , Personal de Enfermería en Hospital/organización & administración , Estaciones de Enfermería
5.
BMC Public Health ; 24(1): 2689, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39358707

RESUMEN

BACKGROUND: Diet-related noncommunicable diseases (NCDs) are a leading cause of ill-health and death across Europe. In Ireland, dietary intakes of saturated fat, free sugar and salt exceed World Health Organization recommendations, and excess consumption follows a social gradient increasing population risk of diet-related NCDs. The retail food environment can influence consumer food choice and subsequent dietary intakes. In high income countries, supermarkets are an increasingly influential actor in consumer food availability, choice, purchase, and subsequent food intake. This study aims to assess the relative availability and prominence of healthy and unhealthy foods in Irish supermarkets, by area-level deprivation. METHODS: This study used a cross-sectional study design, and applied a validated measure, as described in the INFORMAS Protocol: Food Retail - Food availability in supermarkets. Between October 2021 and February 2022, shelf space (m2) (height or depth (cm) × length (cm)) and prominence (visibility), of foods, classified as healthy and unhealthy and represented by a proxy indicator, were collected in supermarkets (n = 36) in County Dublin, Ireland. Overall the proportion of mean relative shelf space (m2), allocated to healthy and unhealthy foods, and its prominence, by area-level deprivation, and retailer, were determined. We used t-tests and one-way ANOVA to analyse possible differences between the proportion of relative shelf space available to healthy and unhealthy foods, and its prominence, by area-level deprivation and retailer. RESULTS: The study found the proportion of shelf space measured allocated to unhealthy food was 68.0% (SD 10.6). Unhealthy foods were more likely to be in areas of high prominence. Overall, there was no statistically significant difference between the proportion of relative shelf space available to unhealthy foods in areas of high and low deprivation. A statistically significant difference in the proportion of relative shelf space allocated to healthy and unhealthy food by area level deprivation was found in one retailer. CONCLUSION: Unhealthy foods had a higher proportion of shelf space and were more prominent than healthy foods in supermarkets in County Dublin, Ireland. The current availability and prominence of foods in supermarkets does not align with Food Based Dietary Guideline recommendations and does not support consumers to make healthier food choices. There is a need for supermarkets in Ireland to improve the availability and prominence of healthy foods to support consumers to make healthier food choices.


Asunto(s)
Abastecimiento de Alimentos , Supermercados , Irlanda , Estudios Transversales , Humanos , Abastecimiento de Alimentos/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Dieta Saludable/estadística & datos numéricos
6.
BMC Anesthesiol ; 24(1): 28, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233786

RESUMEN

BACKGROUND: During arthroscopic rotator cuff repair (ARCR), clear surgical field visibility (SFV) is the basis of successful surgery, but the choice of anesthesia maintenance drugs may have different effects on SFV. In this study, we aimed to compare the effects of propofol- and sevoflurane-based general anesthesia on SFV in patients undergoing ARCR. METHODS: Patients (n = 130) undergoing elective ARCR in the lateral decubitus position were randomized into either the propofol group or sevoflurane group (65 per group). The duration of surgery and increased pressure irrigation (IPI), Boezaart score, rocuronium consumption and usage of remifentanil were recorded. The time of both spontaneous respiration recovery and extubation and the incidences of postoperative nausea and vomiting and agitation were also recorded. RESULTS: The Boezaart score, duration of IPI and ratio of the duration of IPI to the duration of surgery (IPI/S ratio) were similar between the groups (P > 0.05). Rocuronium consumption, number of patients requiring remifentanil infusion and total remifentanil consumption were significantly lower in the sevoflurane group (P < 0.05). The spontaneous respiration recovery time was significantly longer in the propofol group (P < 0.05), but there were no differences in the extubation time between the groups(P > 0.05). CONCLUSIONS: Compared with propofol, sevoflurane provides equally clear SFV while improving the convenience of anesthesia maintenance in ARCR patients with interscalene plexus (ISB) combined with general anesthesia. TRIAL REGISTRATION: This single-center, prospective, RCT was retrospective registered at Chinese Clinical Trial Registry with the registration number ChiCTR2300072110 (02/06/2023).


Asunto(s)
Anestésicos por Inhalación , Éteres Metílicos , Propofol , Humanos , Propofol/farmacología , Sevoflurano , Remifentanilo , Rocuronio , Estudios Prospectivos , Manguito de los Rotadores/cirugía , Estudios Retrospectivos , Éteres Metílicos/farmacología , Piperidinas/farmacología , Anestesia General , Anestésicos Intravenosos/farmacología , Anestésicos por Inhalación/farmacología
7.
BMC Pediatr ; 24(1): 248, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600453

RESUMEN

AIM: Age estimation plays a critical role in personal identification, especially when determining compliance with the age of consent for adolescents. The age of consent refers to the minimum age at which an individual is legally considered capable of providing informed consent for sexual activities. The purpose of this study is to determine whether adolescents meet the age of 14 or 18 by using dental development combined with machine learning. METHODS: This study combines dental assessment and machine learning techniques to predict whether adolescents have reached the consent age of 14 or 18. Factors such as the staging of the third molar, the third molar index, and the visibility of the periodontal ligament of the second molar are evaluated. RESULTS: Differences in performance metrics indicate that the posterior probabilities achieved by machine learning exceed 93% for the age of 14 and slightly lower for the age of 18. CONCLUSION: This study provides valuable insights for forensic identification for adolescents in personal identification, emphasizing the potential to improve the accuracy of age determination within this population by combining traditional methods with machine learning. It underscores the importance of protecting and respecting the dignity of all individuals involved.


Asunto(s)
Determinación de la Edad por los Dientes , Humanos , Adolescente , Determinación de la Edad por los Dientes/métodos , Radiografía Panorámica , Tercer Molar , Ligamento Periodontal , Aprendizaje Automático
8.
Childs Nerv Syst ; 40(9): 2825-2828, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39044040

RESUMEN

PURPOSE: This study aims to evaluate the effectiveness of the Piezosurgery® device in endoscopic-assisted correction of trigonocephaly. Trigonocephaly is a type of craniosynostosis characterized by a triangular-shaped forehead due to the premature fusion of the metopic suture. Traditional open cranial vault reconstruction, although common, is invasive and poses risks. The study explores a less invasive alternative using ultrasonic microvibrations for bone cutting, potentially reducing soft tissue damage and improving surgical outcomes. METHODS: The Piezosurgery® device was employed in endoscopic trigonocephaly correction surgeries performed on patients under 4 months old at the French Referral Center for Craniosynostosis in Lyon. The technique involves making a small skin incision and performing osteotomies from the anterior fontanel to the glabella. A rigid 0° endoscope provides visibility, and the Piezosurgery® device enables precise bone cutting while preserving the dura mater. Post-surgery, patients were discharged within 3 days and required to wear a remodeling helmet for 6-8 months. RESULTS: The use of Piezosurgery® device allowed precise osteotomies with minimal soft tissue damage. No dura mater injuries occurred in the patient series. The procedure was efficient, with an average duration of 80 min, and blood loss was minimal, reducing the need for blood transfusions. The endoscopic approach facilitated shorter surgical times and reduced postoperative infection risks. Enhanced visibility during surgery, due to cavitation effects, improved the accuracy of bone cuts. The technique demonstrated promising safety and esthetic outcomes, although it incurred higher costs compared to traditional methods. CONCLUSION: Piezosurgery® device provides a safe and effective method for minimally invasive endoscopic correction of trigonocephaly. The device's ability to selectively cut bone while preserving soft tissues offers significant advantages, despite longer surgical times and higher costs. This technique represents a viable alternative to traditional open surgery, promoting better clinical outcomes and reduced recovery times.


Asunto(s)
Craneosinostosis , Piezocirugía , Humanos , Craneosinostosis/cirugía , Lactante , Piezocirugía/métodos , Piezocirugía/instrumentación , Masculino , Femenino , Neuroendoscopía/métodos , Neuroendoscopía/instrumentación , Resultado del Tratamiento , Endoscopía/métodos
9.
Ecotoxicol Environ Saf ; 285: 117107, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39332195

RESUMEN

BACKGROUND: Fine particulate matter (PM2.5) is noxious to female reproductive development and facilitates the occurrence of subsequent diseases. Early menopause is initiative factor of female aging. But due to the lack of historical exposure of PM2.5, we could not gain insight into the linkage between ambient PM2.5 exposure and early menopause. METHODS: We conducted a community-based retrospective cross-sectional study and pooled 1173 postmenopausal women. The machine learning algorithm of LightGBM was processed to derive the historical concentrations of PM2.5 based on aerography of 1956-2022. The quantile g-computation and binary logistic regression were employed to estimate the mixed and single associations between PM2.5 and early menopause. RESULTS: The visibility topped the most important feature for derivations of historical PM2.5 concentrations. The R2 of 10-fold cross-validation and predictive capability during processing were all above 0.8. The prevalence of early menopause was 7.3 %. Each 10 µg/m3 PM2.5 increased the prevalence of early menopause during prior 2 years exposure (OR: 1.49, 95 %CI: 1.03-2.16) and spring and autumn (OR: 1.28, 95 %CI: 1.07-1.54). After adjusting the reverse effects of temperature, the prior 2 years exposure of PM2.5 remained positively associated with early menopause in the fourth quantile vs the first quantile (OR: 3.36, 95 %CI: 1.53-7.36) in the spring and autumn. The higher BMI (OR: 1.40, 95 %CI: 1.14-1.72), waistline (OR: 1.42, 95 %CI: 1.09-1.85) and unfavourable dietary habits of less meat (OR: 1.72, 95 %CI: 1.11-2.68), more fried food (OR: 2.39, 95 %CI: 1.15-4.99) elevated the prevalence of early menopause. CONCLUSIONS: The accurate environmental exposure assessment of historical PM2.5 vigorously promoted the researches on the relationship between PM2.5 and early menopause. It sounds the alarm on female infertility menace associated with particulate matter especially during the turbulent 2 years before menopause.

10.
Sensors (Basel) ; 24(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38894097

RESUMEN

Road safety is a serious concern worldwide, and traffic signs play a critical role in confirming road safety, particularly in the context of AVs. Therefore, there is a need for ongoing advancements in traffic sign evaluation methodologies. This paper comprehensively analyzes the relationship between traffic sign retroreflectivity and LiDAR intensity to enhance visibility and communication on road networks. Using Python 3.10 programming and statistical techniques, we thoroughly analyzed handheld retroreflectivity coefficients alongside LiDAR intensity data from two LiDAR configurations: 2LRLiDAR and 1CLiDAR systems. The study focused specifically on RA1 and RA2 traffic sign classes, exploring correlations between retroreflectivity and intensity and identifying factors that may impact their performance. Our findings reveal variations in retroreflectivity compliance rates among different sign categories and color compositions, emphasizing the necessity for targeted interventions in sign design and production processes. Additionally, we observed distinct patterns in LiDAR intensity distributions, indicating the potential of LiDAR technology for assessing sign visibility. However, the limited correlations between retroreflectivity and LiDAR intensity underscore the need for further investigation and standardization efforts. This study provides valuable insights into optimizing traffic sign effectiveness, ultimately contributing to improved road safety conditions.

11.
Sensors (Basel) ; 24(18)2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39338675

RESUMEN

The density of fog is directly related to visibility and is one of the decision-making criteria for airport flight management and highway traffic management. Estimating fog density based on images and videos has been a popular research topic in recent years. However, the fog density estimated results based on images should be further evaluated and analyzed by combining weather information from other sensors. The data obtained by different sensors often need to be aligned in terms of time because of the difference in acquisition methods. In this paper, we propose a video and a visibility data alignment method based on temporal consistency for data alignment. After data alignment, the fog density estimation results based on images and videos can be analyzed, and the incorrect estimation results can be efficiently detected and corrected. The experimental results show that the new method effectively combines videos and visibility for fog density estimation.

12.
J Environ Manage ; 352: 120070, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38266524

RESUMEN

Wind power is one of the fastest growing renewable energy sectors and plays a focal role in the transition to a fossil fuel free society in Europe. Technological developments have enabled the construction of turbines within forested areas, which has raised concerns regarding the audio-visual impact on these landscapes. However, there is a paucity of research with regard to the role that forests may play in mitigating the negative impacts of wind farms. In this study, we created a simplified model for noise attenuation based on the ISO 9613-2 and Nord2000 noise models and a visibility model which both relates the audio-visual effect to forest stand structure and applied them in the GIS environment. Our findings suggest that forests can act as effective noise barriers, with the sound attenuation level dependent on the distance that sound travels through the forest, as well as the size and density of the trees. However, in the case of a high elevation sound source (such as wind turbines), the forest begins to act as a noise shield from a distance of between 500 and 1500 m, depending on the height of the forest and the land topography. While current noise models do not consider the impact of tree species, our visibility model accounts for tree size, density and species, as well as understorey and thinning. Our results indicate that spruce trees provide a better visual constraint whereas visibility distances within mature Calluna-type pine forests tend to be more extensive. Both models include variables that can be adjusted by forest management, thereby allowing integration with forest planning software. Overall, this study presents indicative methods for the evaluation of potential forest landscape shields, a concept that could have broad applications, including Landscape Value Trading.


Asunto(s)
Fuentes Generadoras de Energía , Viento , Bosques , Árboles , Ruido
13.
Public Health Nurs ; 41(2): 193-197, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37994294

RESUMEN

Farm work is one of the nation's most hazardous occupations, and migrant and seasonal farmworkers face significant health inequities. Awareness and understanding of the needs of this population are crucial in assuring they receive appropriate support. Documentary programs can raise awareness of community member views to better inform services and advocacy efforts. Visions for the future of farm work were collected from farmworkers and persons supporting them through a community-based, participatory documentary project led by Student Action with Farmworkers (SAF) from 2021 to 2022. Seventy-nine submissions from participants in North and South Carolina, including text responses and file uploads, were collected and thematically analyzed. Five themes were identified: (1) employment benefits and conditions, (2) living conditions, (3) health access and quality, (4) dignity and visibility of farm work, and (5) policy change for a better future. The visions for the future of farm work expressed by these agricultural workers, advocates, and students raise important implications for agricultural communities, public health practitioners, researchers, funders, and policymakers. Application of these findings in the development and delivery of public health services for farmworkers has the potential to positively impact the morbidity and mortality rates of this at-risk population.


Asunto(s)
Agricultores , Migrantes , Humanos , Granjas , Factores de Riesgo , Estudiantes , Agricultura
14.
Environ Monit Assess ; 196(9): 865, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39212804

RESUMEN

Urban environment and air quality are changing primarily due to land use land cover (LULC) changes, economic activity, and urbanization. Air pollution has been increasingly acknowledged as a major issue for cities due to its extensive effects on health and well-being. As the second most populous city in the country, Lahore faces alarming levels of air pollutants, which induced this study to focus on the pervasive issue of air pollution in Lahore. For this, the study collected air pollutants data from the Environmental Protection Department of Punjab and analyzed them using the ARIMA model. In the research results, both the observed data and predictive models uncovered concerning trends in pollutant concentrations, ultimately portraying a concerning picture for air quality management. Carbon monoxide (CO) levels show a consistent rise, surpassing Pakistan's environmental standards by 2025. Similarly, nitrogen dioxide (NO2) concentrations escalate, exceeding prescribed standards. Ground-level ozone (O3) also demonstrates a substantial increase, surpassing standards by 2025. Both PM2.5 and PM10 exhibit marked upward trends, projected to exceed recommended limits, particularly PM10 throughout the study year. The Air Quality Index exhibits an observable upward trend, fluctuating between 70 and 442 from 2015 to 2020. Similarly, a positive correlation was found between population growth and land use conversion into residential areas. Projections suggest a continuous increase, potentially hitting a severe level of 500 during winter by 2025. These findings point to an impending air pollution crisis, demanding urgent action to address the hazardous situation in the city. The study recommends that urban air pollution should be reduced, and the negative health effects of air pollution should be minimized using vegetation barriers, screens, and greening initiatives. Strict regulations and monitoring initiatives need to be put in place in big cities to monitor pollution and vegetation.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Desarrollo Sostenible , Pakistán , Contaminación del Aire/estadística & datos numéricos , Contaminantes Atmosféricos/análisis , Ozono/análisis , Dióxido de Nitrógeno/análisis , Monóxido de Carbono/análisis , Ciudades , Material Particulado/análisis
15.
Entropy (Basel) ; 26(4)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38667895

RESUMEN

We investigate whether it is possible to distinguish chaotic time series from random time series using network theory. In this perspective, we selected four methods to generate graphs from time series: the natural, the horizontal, the limited penetrable horizontal visibility graph, and the phase space reconstruction method. These methods claim that the distinction of chaos from randomness is possible by studying the degree distribution of the generated graphs. We evaluated these methods by computing the results for chaotic time series from the 2D Torus Automorphisms, the chaotic Lorenz system, and a random sequence derived from the normal distribution. Although the results confirm previous studies, we found that the distinction of chaos from randomness is not generally possible in the context of the above methodologies.

16.
Entropy (Basel) ; 26(8)2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39202105

RESUMEN

The integration of terrestrial- and satellite-based quantum key distribution (QKD) experiments has markedly advanced global-scale quantum networks, showcasing the growing maturity of quantum technologies. Notably, the use of unmanned aerial vehicles (UAVs) as relay nodes has emerged as a promising method to overcome the inherent limitations of fiber-based and low-Earth orbit (LEO) satellite connections. This paper introduces a protocol for measurement-device-independent QKD (MDI-QKD) using photon orbital angular momentum (OAM) encoding, with UAVs as relay platforms. Leveraging UAV mobility, the protocol establishes a secure and efficient link, mitigating threats from untrusted UAVs. Photon OAM encoding addresses reference frame alignment issues exacerbated by UAV jitter. A comprehensive analysis of atmospheric turbulence, state-dependent diffraction (SDD), weather visibility, and pointing errors on free-space OAM-state transmission systems was conducted. This analysis elucidates the relationship between the key generation rate and propagation distance for the proposed protocol. Results indicate that considering SDD significantly decreases the key rate, halving previous data results. Furthermore, the study identifies a maximum channel loss capacity of 26 dB for the UAV relay platform. This result is pivotal in setting realistic parameters for the deployment of UAV-based quantum communications and lays the foundation for practical implementation strategies in the field.

17.
Forensic Sci Med Pathol ; 20(1): 8-13, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36853501

RESUMEN

The purpose of this study is to estimate chronological age and determine whether individuals were aged under or over 18 years using root pulp visibility (RPV) in cone-beam computed tomography (CBCT) images. The study included CBCT images of 699 individuals aged between 15 and 75 years. One thousand twenty-three mandibular second molar (2M) teeth were evaluated using Olze's RPV method in four stages. Descriptive statistics of the stages and the relationship between the stages and the chronological age were assessed. The distribution of the stages was analyzed according to the 18-year age threshold. There was a positive correlation between RPV stages and chronological ages in both sexes. For females and males, the mean ages of stage 0, stage 1, and stage 2, for females and males, were found as 27.21, 28.93, and 33.68 years, and 37.69, 40.9, and 44.88 years, respectively. Stage 0 and stage 1 were found both in individuals aged under and over 18 years, and stage 2 and stage 3 were not observed in individuals aged under 18 years. The presence of stage 2 and stage 3 may be an indication that an individual is aged over 18 years according to Olze's RPV age estimation method. For more reliable results, 2M teeth should be examined bilaterally in forensic science.


Asunto(s)
Mandíbula , Diente Molar , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Adolescente , Adulto Joven , Anciano , Mandíbula/diagnóstico por imagen , Diente Molar/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Pulpa Dental/diagnóstico por imagen
18.
Rev Infirm ; 73(297): 39-40, 2024 Jan.
Artículo en Francés | MEDLINE | ID: mdl-38242622

RESUMEN

Rigorous monitoring of vital functions in intensive care requires optimal visibility of patients and their environment. Conversely, respect for privacy is an ethical imperative to respect. Liquid crystal electrical film is a device that can be applied to windows and can take opaque or transparent form on demand. Its use could satisfy the visibility of patients and respect for their privacy.


Asunto(s)
Unidades de Cuidados Intensivos , Privacidad , Humanos , Cuidados Críticos , Pacientes
19.
J Neurosci ; 42(12): 2562-2569, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35121637

RESUMEN

A key goal of consciousness science is identifying neural signatures of being aware versus unaware of simple stimuli. This is often investigated in the context of near-threshold detection, with reports of stimulus awareness being linked to heightened activation in a frontoparietal network. However, because of reports of stimulus presence typically being associated with higher confidence than reports of stimulus absence, these results could be explained by frontoparietal regions encoding stimulus visibility, decision confidence, or both. In an exploratory analysis, we leverage fMRI data from 35 human participants (20 females) to disentangle these possibilities. We first show that, whereas stimulus identity was best decoded from the visual cortex, stimulus visibility (presence vs absence) was best decoded from prefrontal regions. To control for effects of confidence, we then selectively sampled trials before decoding to equalize confidence distributions between absence and presence responses. This analysis revealed striking differences in the neural correlates of subjective visibility in PFC ROIs, depending on whether or not differences in confidence were controlled for. We interpret our findings as highlighting the importance of controlling for metacognitive aspects of the decision process in the search for neural correlates of visual awareness.SIGNIFICANCE STATEMENT While much has been learned over the past two decades about the neural basis of visual awareness, the role of the PFC remains a topic of debate. By applying decoding analyses to functional brain imaging data, we show that prefrontal representations of subjective visibility are contaminated by neural correlates of decision confidence. We propose a new analysis method to control for these metacognitive aspects of awareness reports, and use it to reveal confidence-independent correlates of perceptual judgments in a subset of prefrontal areas.


Asunto(s)
Corteza Visual , Estado de Conciencia/fisiología , Femenino , Humanos , Juicio , Imagen por Resonancia Magnética , Masculino , Estimulación Luminosa/métodos , Corteza Visual/fisiología , Percepción Visual/fisiología
20.
J Synchrotron Radiat ; 30(Pt 5): 910-916, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37610345

RESUMEN

Vertical beam size measurements were carried out at Beijing Electron-Positron Collider II (BEPCII) using a phase grating and an absorption grating based on the Talbot effect. The transverse coherence of synchrotron radiation is closely related to beam size. Due to the partial coherence of the synchrotron radiation source, the coherence length can be calculated by measuring the visibility decay of interferograms recorded at different distances behind the gratings. A vertical beam size of 68.19 ± 2 µm was obtained based on the relationship between the coherence length and beam size at the 3W1 beamline of BEPCII. A comparison of the vertical emittance derived from the grating Talbot method and the synchrotron radiation visible light interferometer method was presented. The vertical emittances from the two methods are 1.41 nm rad and 1.40 nm rad, respectively. The 0.1% difference indicates that the grating Talbot method for beam size measurement is reliable. This technique has great potential for small beam size measurement of fourth-generation synchrotron radiation light sources, considering its small diffraction limitation and simple experimental setups.

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