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Despite being highly preventable, cervical cancer is the fourth most common cancer and cause of cancer death in women globally. In low-income countries, cervical cancer is often the leading cause of cancer-related morbidity and mortality. Women living with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome are at a particularly high risk of cervical cancer because of an impaired immune response to human papillomavirus, the obligate cause of virtually all cervical cancers. Globally, approximately 1 in 20 cervical cancers is attributable to HIV; in sub-Saharan Africa, approximately 1 in 5 cervical cancers is due to HIV. Here, the authors provide a critical appraisal of the evidence to date on the impact of HIV disease on cervical cancer risk, describe key methodologic issues, and frame the key outstanding research questions, especially as they apply to ongoing global efforts for prevention and control of cervical cancer. Expanded efforts to integrate HIV care with cervical cancer prevention and control, and vice versa, could assist the global effort to eliminate cervical cancer as a public health problem.
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Infecções por HIV/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Detecção Precoce de Câncer , Feminino , Humanos , Hospedeiro Imunocomprometido , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Lesões Pré-Cancerosas/terapia , Prevenção Primária , Prevenção SecundáriaRESUMO
Molecular clustering analysis has been developed to facilitate visual inspection in the process of structure-based virtual screening. However, traditional methods based on molecular fingerprints or molecular descriptors limit the accuracy of selecting active hit compounds, which may be attributed to the lack of representations of receptor structural and protein-ligand interaction during the clustering. Here, a novel deep clustering framework named ClusterX is proposed to learn molecular representations of protein-ligand complexes and cluster the ligands. In ClusterX, the graph was used to represent the protein-ligand complex, and the joint optimisation can be used efficiently for learning the cluster-friendly features. Experiments on the KLIFs database show that the model can distinguish well between the binding modes of different kinase inhibitors. To validate the effectiveness of the model, the clustering results on the virtual screening dataset further demonstrated that ClusterX achieved better or more competitive performance against traditional methods, such as SIFt and extended connectivity fingerprints. This framework may provide a unique tool for clustering analysis and prove to assist computational medicinal chemists in visual decision-making.
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Ligantes , Análise por ConglomeradosRESUMO
BACKGROUND: As a gold-standard quantitative technique based on mass spectrometry, multiple reaction monitoring (MRM) has been widely used in proteomics and metabolomics. In the analysis of MRM data, as no peak picking algorithm can achieve perfect accuracy, manual inspection is necessary to correct the errors. In large cohort analysis scenarios, the time required for manual inspection is often considerable. Apart from the commercial software that comes with mass spectrometers, the open-source and free software Skyline is the most popular software for quantitative omics. However, this software is not optimized for manual inspection of hundreds of samples, the interactive experience also needs to be improved. RESULTS: Here we introduce MRMPro, a web-based MRM data analysis platform for efficient manual inspection. MRMPro supports data analysis of MRM and schedule MRM data acquired by mass spectrometers of mainstream vendors. With the goal of improving the speed of manual inspection, we implemented a collaborative review system based on cloud architecture, allowing multiple users to review through browsers. To reduce bandwidth usage and improve data retrieval speed, we proposed a MRM data compression algorithm, which reduced data volume by more than 60% and 80% respectively compared to vendor and mzML format. To improve the efficiency of manual inspection, we proposed a retention time drift estimation algorithm based on similarity of chromatograms. The estimated retention time drifts were then used for peak alignment and automatic EIC grouping. Compared with Skyline, MRMPro has higher quantification accuracy and better manual inspection support. CONCLUSIONS: In this study, we proposed MRMPro to improve the usability of manual calibration for MRM data analysis. MRMPro is free for non-commercial use. Researchers can access MRMPro through http://mrmpro.csibio.com/ . All major mass spectrometry formats (wiff, raw, mzML, etc.) can be analyzed on the platform. The final identification results can be exported to a common.xlsx format for subsequent analysis.
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Algoritmos , Compressão de Dados , Humanos , Calibragem , Espectrometria de Massas/métodos , Software , InternetRESUMO
While the incidence of cervical cancer has dropped in high-income countries due to organized cytology-based screening programs, it remains the leading cause of cancer death among women in Eastern Africa. Therefore, the World Health Organization (WHO) now urges providers to transition from widely prevalent but low-performance visual inspection with acetic acid (VIA) screening to primary human papillomavirus (HPV) DNA testing. Due to high HPV prevalence, effective triage tests are needed to identify those lesions likely to progress and so avoid over-treatment. To identify the optimal cost-effective strategy, we compared the VIA screen-and-treat approach to primary HPV DNA testing with p16/Ki67 dual-stain cytology or VIA as triage. We used a Markov model to calculate the budget impact of each strategy with incremental quality-adjusted life years and incremental cost-effectiveness ratios (ICER) as the main outcome. Deterministic cost-effectiveness analyses show that the screen-and-treat approach is highly cost-effective (ICER 2469 Int$), while screen, triage, and treat with dual staining is the most effective with favorable ICER than triage with VIA (ICER 9943 Int$ compared with 13,177 Int$). One-way sensitivity analyses show that the results are most sensitive to discounting, VIA performance, and test prices. In the probabilistic sensitivity analyses, the triage option using dual stain is the optimal choice above a willingness to pay threshold of 7115 Int$ being cost-effective as per WHO standards. The result of our analysis favors the use of dual staining over VIA as triage in HPV-positive women and portends future opportunities and necessary research to improve the coverage and acceptability of cervical cancer screening programs.
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Análise de Custo-Efetividade , Detecção Precoce de Câncer , Infecções por Papillomavirus , População Rural , Neoplasias do Colo do Útero , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Ácido Acético , Detecção Precoce de Câncer/economia , Detecção Precoce de Câncer/métodos , Quênia/epidemiologia , Cadeias de Markov , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/economia , Infecções por Papillomavirus/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/economia , Neoplasias do Colo do Útero/epidemiologiaRESUMO
The microwave and millimeter-wave (MMW) imaging technology is gaining increasing interest for food inspection. It allows for noninvasive, contactless, and fast scanning capabilities, while being cost-efficient and safe to human. This review paper introduces the fundamentals in the interaction of electromagnetic wave with food materials and the current MMW sensing and imaging systems used for foods. Then we present emerging technologies in MMW imaging for inspecting food quality and safety, aiming to meet the modern food industry's demand. According to the most recent technological advancements, it is expected that high-performance antenna, ultrawide bandwidth signal generation, nano-scale semiconductor technologies, radio frequency identification with inductance-capacitance resonator, and machine learning could significantly enhance the capabilities of MMW imaging systems for food inspection.
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Cognitive fatigue (CF) can lead to an increase in the latency of simple reaction time, although the processes involved in this delay are unknown. One potential explanation is that a longer time may be required for sensory processing of relevant stimuli. To investigate this possibility, the current study used a visual inspection time task to measure perceptual processing speed before and after a CF (math and memory) or non-fatiguing (documentary film) intervention. Subjective fatigue and simple reaction time significantly increased following the CF, but not the non-fatiguing intervention, confirming that CF was induced. Conversely, there was no effect of CF on inspection time task performance. It was therefore concluded that the speed of perceptual processing is not significantly impacted by CF, and thus is unlikely to underlie CF-related reaction time increases. Instead, increases in simple reaction time latency in CF may be due to delays in response preparation or initiation.
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Cognição , Percepção Visual , Humanos , Percepção Visual/fisiologia , Tempo de Reação/fisiologia , Cognição/fisiologia , Análise e Desempenho de Tarefas , Fadiga Mental/psicologiaRESUMO
BACKGROUND: There is increasing evidence of a higher risk and poorer prognosis of cervical cancer among women with diabetes mellitus (DM) compared to the general population. These are mediated by higher susceptibility to persistent high-risk human papillomavirus (hr-HPV) infection due to dysfunctional clearance in an immunocompromised state. We aimed to determine the prevalence of hr-HPV infection and cervical lesions in a cohort of women with DM in Ghana. We further disaggregated the prevalence according to DM type and explored factors associated with hr-HPV infection. METHODS: This retrospective descriptive cross-sectional study assessed 198 women with DM who underwent cervical screening via concurrent hr-HPV DNA testing and visual inspection with acetic acid in an outpatient department of the National Diabetes Management and Research Centre in Korle-Bu Teaching Hospital, Accra from March to May 2022. Univariate and multivariable binary logistic regression were used to explore factors associated with hr-HPV positivity. RESULTS: Among 198 women with DM (mean age, 60.2 ± 12.1 years), the overall hr-HPV prevalence rate was 21.7% (95% CI, 16.1-28.1), disaggregated as 1.5% (95% CI, 0.3-4.4) each for HPV16 and HPV18 and 20.7% (95% CI, 15.3-27.0) for other HPV genotype(s). Respective hr-HPV prevalence rates were 37.5% (95% CI, 15.2-64.6) for type 1 DM, 19.8% (95% CI, 13.9-26.7) for type 2 DM, and 25.0% (95% CI, 8.7-49.1) for unspecified/other DM types. Past use of the combined contraceptive pill independently increased the risk of hr-HPV infection by approximately three times (adjusted odds ratio [aOR] = 2.98; 95% CI, 1.03 - 8.64; p-value = 0.045), whereas each unit increase in FBG level increased the odds of hr-HPV infection by about 15% (aOR = 1.15; 95% CI, 1.02 - 1.30; p-value = 0.021). CONCLUSION: Our study points to a high prevalence of hr-HPV among women with DM and highlights a need for glycemic control among them as this could contribute to lowering their odds of hr-HPV infection. The low overall rates of HPV vaccination and prior screening also indicate a need to build capacity and expand the scope of education and services offered to women with DM as regards cervical precancer screening.
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Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Gana/epidemiologia , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/complicações , Pessoa de Meia-Idade , Prevalência , Estudos Transversais , Estudos Retrospectivos , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Idoso , Adulto , Fatores de Risco , Diabetes Mellitus/epidemiologia , Papillomaviridae/genéticaRESUMO
BACKGROUND: Cervical cancer continues to disproportionately burden women in low/middle-income countries like Ghana. We examined treatment patterns and histopathological outcomes among women screened using visual inspection with acetic acid (VIA) and/or mobile colposcopy who subsequently underwent thermal ablation, large loop excision of the transformation zone (LLETZ), or cold knife conization at the Cervical Cancer Prevention and Training Centre, Battor. We also assessed the prevalence of cervical intraepithelial neoplasia 2+ (CIN2+) or micro-invasive disease and their associated factors for women who underwent excisional treatments. The treatment choices for cervical precancerous lesions suitable for resource-limited settings have also been described from the perspective of a center that manages a heterogenous population. METHODS: We conducted an analysis of secondary data collected between June 2016 and June 2023 among women with positive findings on VIA or mobile colposcopy who subsequently underwent thermal ablation or large loop excision of the transformation zone (LLETZ). The prevalence of histopathology outcomes, including no dysplasia, CIN1 - 3, and micro-invasive disease, were estimated with 95% confidence intervals (CIs). Factors associated with histopathological findings were modeled using multinomial logistic regression. RESULTS: For the study period, 14 (10.6%) of the total 132 participants underwent cervical lesion treatment at outreach locations, all via thermal ablation. The remaining 118 (89.4%) were treated at the Catholic Hospital, Battor using LLETZ (n = 66, 55.9%), thermal ablation (n = 51, 43.2%), and cold knife conization (n = 1, 0.9%). Among 65 women with histopathology reports, the most frequent histopathological finding was no dysplasia (47.7%; 95% CI, 35.1 - 60.5), followed by CIN2 and CIN3 (20.0%; 95% CI, 11.1 - 31.8 each), CIN1 (7.7%; 95% CI, 2.5 - 17.0) and micro-invasion (4.6%; 95% CI, 1.0 - 12.9). Those with micro-invasive disease were significantly older than those with CIN1, CIN2, and CIN3 (p = 0.036, 0.022, 0.009, respectively), but not significantly older than those who showed no dysplasia (p = 0.088). For each unit increase in age, the likelihood of CIN3 was relatively significantly reduced compared to no dysplasia (crude relative risk ratio [RRR] = 0.93; 95% CI, 0.86 - 0.99). This association was neither observed with the remaining histopathological groups nor for parity and persisted after controlling for parity (adjusted RRR = 0.92; 95% CI, 0.85 - 0.99; p = 0.025). CONCLUSION: This paper largely demonstrates treatment options available to women and practitioners in LMICs. The high combined prevalence of high-grade precancerous lesions and micro-invasive disease underscores the need to increase cervical cancer awareness that would enhance screening attendance and hasten efforts at moving from opportunistic to organized screening in Ghana. This will enhance early cervical lesion detection and treatment, while simultaneously re-evaluating and cutting down on unnecessary treatment.
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Colposcopia , Hospitais de Distrito , Lesões Pré-Cancerosas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Humanos , Feminino , Gana/epidemiologia , Neoplasias do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/patologia , Adulto , Displasia do Colo do Útero/cirurgia , Displasia do Colo do Útero/epidemiologia , Pessoa de Meia-Idade , Colposcopia/estatística & dados numéricos , Colposcopia/métodos , Hospitais de Distrito/estatística & dados numéricos , Lesões Pré-Cancerosas/cirurgia , Lesões Pré-Cancerosas/patologia , Adulto Jovem , Conização/métodos , Conização/estatística & dados numéricos , Região de Recursos LimitadosRESUMO
INTRODUCTION: Despite breakthroughs in cervical cancer detection, resource-constrained countries continue to have a disproportionately high incidence and death rate. Mhealth has been identified as an important tool for increasing cervical cancer screening rates in Sub-Saharan Africa. We determined whether sending Ghanaian women culturally tailored one-way mobile phone SMS text messages about cervical cancer would encourage the uptake of the human papillomavirus (HPV) test. METHODS: From August to November 2016, 88 women aged 18 to 39 living or working in an urban community (Accra, Ghana) participated in a quasi-experimental study. For 8 weeks, 32 SMS messages regarding cervical cancer were developed and sent to the personal phones of intervention arm participants (n = 42). Women in the control group (n = 46) received SMS texts with general health and lifestyle advice. Fischer's exact tests were performed to assess cervical cancer screening uptake and associated reasons for non-uptake between the intervention and control groups (p < 0.05). RESULTS: At the baseline, women differed in terms of ethnicity and wealth. After the intervention, participants' self-reported risk factors for cervical cancer, such as early menarche, usual source of medical treatment, family history of cancer, smoking, and alcohol history, changed. None of the women in the intervention group sought cervical cancer screening after the intervention, but only one (2.2%) of the control arm participants did. Almost all the women (> 95%) agreed that an HPV test was essential and that regular healthcare check-ups could help prevent cervical cancer. Some women believed that avoiding particular foods could help prevent cervical cancer (23.8% intervention vs. 58.7% control, p < 0.001). Time constraints and out-of-pocket expenses were significant barriers to cervical cancer screening. CONCLUSION: A one-way SMS delivered to urban women did not increase cervical cancer screening attendance. The time spent in screening facilities and the lack of coverage by the National Health Insurance Scheme limited screening uptake. We urge for the establishment of screening centers in all healthcare facilities, as well as the inclusion of cervical cancer screening in healthcare programs through cost-sharing.
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Infecções por Papillomavirus , Envio de Mensagens de Texto , Neoplasias do Colo do Útero , Adolescente , Adulto , Feminino , Humanos , Adulto Jovem , Detecção Precoce de Câncer , Gana , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controleRESUMO
Cheek and Johnston (JMB 86:70, 2023) consider a continuous-time Bienaymé-Galton-Watson tree conditioned on being alive at time T. They study the reproduction events along the ancestral lineage of an individual randomly sampled from all those alive at time T. We give a short proof of an extension of their main results (Cheek and Johnston in JMB 86:70, 2023, Theorems 2.3 and 2.4) to the more general case of Bellman-Harris processes. Our proof also sheds light onto the probabilistic structure of the rate of the reproduction events. A similar method will be applied to explain (i) the different ancestral reproduction bias appearing in work by Geiger (JAP 36:301-309, 1999) and (ii) the fact that the sampling rule considered by Chauvin et al. (SPA 39:117-130, 1991), (Theorem 1) leads to a time homogeneous process along the ancestral lineage.
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Reprodução , Modelos Genéticos , Animais , Filogenia , Conceitos MatemáticosRESUMO
Olfaction is one of the evolutionarily oldest senses and plays a fundamental role in foraging and social interactions across mammals. In primates, the role of olfaction is now well recognized, but better investigated in strepsirrhine and platyrrhine primates than in catarrhines. We observed the sniffing behavior of semi-free ranging Barbary macaques, Macaca sylvanus, at Affenberg Salem, Germany, to assess how frequently macaques sniff and in which contexts, and how sniffing is affected by sex and age. Focal observations of 24 males and 24 females aged 1-25 years showed that Barbary macaques sniffed, on average, 5.24 times per hour, with more than 80% of sniffs directed at food. Irrespective of the context, younger individuals sniffed more often than older ones. Females' sniffs were more often directed at food than male sniffs, while males sniffed more often than females in a social context. Sniffs at conspecifics occurred primarily in a sexual context, with 70% of social sniffs directed at female anogenital swellings performed by males. Of the observed 176 anogenital inspections, 51 involved sniffing of the swelling. Olfactory inspections were followed by copulation significantly less often than merely visual inspections, suggesting that anogenital odors may play a role in male mating decisions, but the role of olfaction in sexual interactions warrants further investigations. In sum, results show that Barbary macaques routinely use olfaction during feeding, but also in a socio-sexual context, corroborating the relevance of the olfactory sense in the lives of catarrhine primates.
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Macaca , Reprodução , Feminino , Masculino , Animais , Copulação , Interação Social , MamíferosRESUMO
OBJECTIVE: The objective was to gain knowledge about how external inspections following serious incidents are played out in a Norwegian hospital context from the perspective of the inspectors, and whether stakeholders' views are involved in the inspection. METHODS: Based on a qualitative mixed methods design, 10 government bureaucrats and inspectors situated at the National Board of Health Supervision and three County Governors in Norway, were strategically recruited, and individual semi-structured interviews were conducted. Key official government documents were selected, collected, and thematically analyzed along with the interview data. RESULTS: Our findings overall demonstrate two overarching themes: Theme (1) Perspectives on different external inspection approaches of responding and involving stakeholders in external inspection following serious incidents, Theme (2) Inspectors' internal work practices versus external expectations. Documents and all participants reported a development towards new approaches in external inspection, with more policies and regulatory attention to sensible involvement of stakeholders. Involvement and interaction with patients and informal caregivers could potentially inform the case complexity and the inspector's decision-making process. However, stakeholder involvement was sometimes complex and challenging due to e.g., difficult communication and interaction with patients and/or informal caregivers, due to resource demands and/or the inspector's lack of experience and/or relevant competence, different perceptions of the principle of sound professional practice, quality, and safety. The inspectors considered balancing the formal objectives and expectations, with the expectations of the public and different stakeholders (i.e. hospitals, patients and/or informal caregivers) a challenging part of their job. This balance was seen as an important part of the continuous development of ensuring public trust and legitimacy in external inspection processes. CONCLUSIONS AND IMPLICATIONS: Our study suggests that the regulatory system of external inspection and its available approaches of responding to a serious incident in the Norwegian setting is currently not designed to accommodate the complexity of needs from stakeholders at the levels of hospital organizations, patients, and informal caregivers altogether. Further studies should direct attention to how the wider system of accountability structures may support the internal work practices in the regulatory system, to better algin its formal objectives with expectations of the public.
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Ácido Algínico , Comunicação , Humanos , Governo , Promoção da Saúde , HospitaisRESUMO
The African planthopper Leptodelphax maculigera (Hemiptera: Delphacidae) has been recently reported in many places in Brazil in association with maize. Its occurrence in maize production fields in Brazil has brought concerns to the corn production chain regarding the possibility of this planthopper to be a vector for maize bushy stunt phytoplasma (MBSP), corn stunt spiroplasma (Spiroplasma kunkelii), maize rayado fino virus (MRFV), and maize striate mosaic virus (MSMV). The phytoplasma and spiroplasma, which are bacteria belonging to the class Mollicutes, and the two viruses are associated with the corn stunt disease complex. Given the presence of the African planthopper species and the corn stunt complex in Brazil, we further investigated the abundance of this planthopper species in the State of Santa Catarina, Brazil, and whether the planthopper can carry the four pathogens. We inspected 12 maize production fields in different municipalities in the state for 20 weeks, using two yellow sticky traps for each maize field. The sticky traps were replaced weekly. A total of 130 specimens of L. maculigera were captured, with a great discrepancy in quantity among locations and weeks. We detected the mollicute MBSP and the viruses MRFV and MSMV in L. maculigera, whereas S. kunkelii was absent in the assessed African planthopper samples. The molecular detection of the phytoplasma and the viruses in field-collected African planthoppers is strong evidence that this insect species has the ability to acquire those pathogens through feeding from the phloem of diseased maize plants. Nonetheless, transmission capacity needs to be experimentally proven to assert L. maculigera as a vector for the corn-stunting pathogens.
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Restaurants are important settings for foodborne illness transmission. Environmental health agencies routinely inspect restaurants to assess compliance with food safety regulations. They also evaluate foodborne illness complaints from consumers to detect potential outbreaks of foodborne illness. Local environmental health agencies were surveyed to identify methods used to conduct surveillance for consumer complaints of foodborne illness, link them to inspection grading and disclosure practices, and evaluate the association between these practices and the number of foodborne illness outbreaks in restaurant settings reported to the Centers for Disease Control and Prevention. We developed a novel framework for assessing the effectiveness of restaurant inspection grading and disclosure of inspection results while accounting for any biases introduced by surveillance factors that affect outbreak detection. Our findings showed the importance of routine restaurant inspection grading and disclosure practices as prevention measures and having a centralized database to manage consumer complaints as a useful surveillance tool for detecting outbreaks. Improving consumer complaint system structure and management can bolster outbreak detection and maximize limited public health resources while increasing the efficiency of complaint-based surveillance.
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Doenças Transmitidas por Alimentos , Restaurantes , Humanos , Doenças Transmitidas por Alimentos/epidemiologia , Surtos de Doenças/prevenção & controle , Inocuidade dos Alimentos , Saúde PúblicaRESUMO
In semiconductor manufacturing, defect inspection in non-patterned wafer production lines is essential to ensure high-quality integrated circuits. However, in actual production lines, achieving both high efficiency and high sensitivity at the same time is a significant challenge due to their mutual constraints. To achieve a reasonable trade-off between detection efficiency and sensitivity, this paper integrates the time delay integration (TDI) technology into dark-field microscopy. The TDI image sensor is utilized instead of a photomultiplier tube to realize multi-point simultaneous scanning. Experiments illustrate that the increase in the number of TDI stages and reduction in the column fixed pattern noise effectively improve the signal-to-noise ratio of particle defects without sacrificing the detecting efficiency.
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A significant percentage of bridges in the United States are serving beyond their 50-year design life, and many of them are in poor condition, making them vulnerable to fatigue cracks that can result in catastrophic failure. However, current fatigue crack inspection practice based on human vision is time-consuming, labor intensive, and prone to error. We present a novel human-centered bridge inspection methodology to enhance the efficiency and accuracy of fatigue crack detection by employing advanced technologies including computer vision and augmented reality (AR). In particular, a computer vision-based algorithm is developed to enable near-real-time fatigue crack detection by analyzing structural surface motion in a short video recorded by a moving camera of the AR headset. The approach monitors structural surfaces by tracking feature points and measuring variations in distances between feature point pairs to recognize the motion pattern associated with the crack opening and closing. Measuring distance changes between feature points, as opposed to their displacement changes before this improvement, eliminates the need of camera motion compensation and enables reliable and computationally efficient fatigue crack detection using the nonstationary AR headset. In addition, an AR environment is created and integrated with the computer vision algorithm. The crack detection results are transmitted to the AR headset worn by the bridge inspector, where they are converted into holograms and anchored on the bridge surface in the 3D real-world environment. The AR environment also provides virtual menus to support human-in-the-loop decision-making to determine optimal crack detection parameters. This human-centered approach with improved visualization and human-machine collaboration aids the inspector in making well-informed decisions in the field in a near-real-time fashion. The proposed crack detection method is comprehensively assessed using two laboratory test setups for both in-plane and out-of-plane fatigue cracks. Finally, using the integrated AR environment, a human-centered bridge inspection is conducted to demonstrate the efficacy and potential of the proposed methodology.
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Algoritmos , Realidade Aumentada , Humanos , Processamento de Imagem Assistida por Computador/métodosRESUMO
Pumping stations have undergone significant modernization and digitalization in recent decades. However, traditional virtual inspections often prioritize the visual experience and fail to effectively represent the haptic physical properties of devices during inspections, resulting in poor immersion and interactivity. This paper presents a novel virtual inspection system for pumping stations, incorporating virtual reality interaction and haptic force feedback technology to enhance immersion and realism. The system leverages a 3D model, crafted in 3Ds Max, to provide immersive visualizations. Multimodal feedback is achieved through a combination of haptic force feedback provided by a haptic device and visual information delivered by a VR headset. The system's data platform integrates with external databases using Unity3D to display relevant information. The system provides immersive 3D visualizations and realistic force feedback during simulated inspections. We compared this system to a traditional virtual inspection method that demonstrated statistically significant improvements in task completion rates and a reduction in failure rates when using the multimodal feedback approach. This innovative approach holds the potential to enhance inspection safety, efficiency, and effectiveness in the pumping station industry.
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The S-transform is a fundamental time-frequency (T-F) domain analysis method in ground penetrating radar (GPR) data processing and can be used for identifying targets, denoising, extracting thin layers, and high-resolution imaging. However, the S-transform spectrum experiences energy leakage near the instantaneous frequency. This phenomenon causes frequency components to erroneously spread over a wider range, impacting the accuracy and precision of GPR data processing. Synchrosqueezing is an effective method to prevent spectrum leakage. In this work, we introduce the synchrosqueezing generalized phase-shifting S-transform (SS-GPST). Initially, it resolves the compatibility issue between the S-transform and the synchrosqueezing strategy through phase-shifting. Subsequently, the SS-GPST accomplishes spectral energy focusing and resolution enhancement via a generalized parameter and synchrosqueezing. A synthetic signal test shows that the SS-GPST excels over other methods at focusing degree, spectral resolution, and signal reconstruction accuracy and speed. In actual GPR tunnel detection data processing, we assess the adaptability of the SS-GPST from three aspects: spectral energy distribution, thin layer identification, and data denoising. The results indicate: (1) compared to other methods, the SS-GPST accurately expresses spectral components with a strong focusing degree and fewer interference components; (2) high-frequency slices of the SS-GPST accurately detect the top and bottom interfaces of a 3.0-3.5 cm reinforcement protection layer; and (3) due to fewer interference components in the SS-GPST spectrum, reconstructing GPR profiles through the SS-GPST inverse transform is an efficient denoising technique. The SS-GPST demonstrates adaptability to different data processing purposes, offers high-resolution T-F spectra, and shows potential to supersede the S-transform.
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In the process of the intelligent inspection of belt conveyor systems, due to problems such as its long duration, the large number of rollers, and the complex working environment, fault diagnosis by acoustic signals is easily affected by signal coupling interference, which poses a great challenge to selecting denoising methods of signal preprocessing. This paper proposes a novel wavelet threshold denoising algorithm by integrating a new biparameter and trisegment threshold function. Firstly, we elaborate on the mutual influence and optimization process of two adjustment parameters and three wavelet coefficient processing intervals in the BT-WTD (the biparameter and trisegment of wavelet threshold denoising, BT-WTD) denoising model. Subsequently, the advantages of the proposed threshold function are theoretically demonstrated. Finally, the BT-WTD algorithm is applied to denoise the simulation signals and the vibration and acoustic signals collected from the belt conveyor experimental platform. The experimental results indicate that this method's denoising effectiveness surpasses that of traditional threshold function denoising algorithms, effectively addressing the denoising preprocessing of idler roller fault signals under strong noise backgrounds while preserving useful signal features and avoiding signal distortion problems. This research lays the theoretical foundation for the non-contact intelligent fault diagnosis of future inspection robots based on acoustic signals.
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Despite achieving numerous successes with surface defect inspection based on deep learning, the industry still faces challenges in conducting packaging defect inspections that include critical information such as ingredient lists. In particular, while previous achievements primarily focus on defect inspection in high-quality images, they do not consider defect inspection in low-quality images such as those containing image blur. To address this issue, we proposed a noble inference technique named temporal-quality ensemble (TQE), which combines temporal and quality weights. Temporal weighting assigns weights to input images by considering the timing in relation to the observed image. Quality weight prioritizes high-quality images to ensure the inference process emphasizes clear and reliable input images. These two weights improve both the accuracy and reliability of the inference process of low-quality images. In addition, to experimentally evaluate the general applicability of TQE, we adopt widely used convolutional neural networks (CNNs) such as ResNet-34, EfficientNet, ECAEfficientNet, GoogLeNet, and ShuffleNetV2 as the backbone network. In conclusion, considering cases where at least one low-quality image is included, TQE has an F1-score approximately 17.64% to 22.41% higher than using single CNN models and about 1.86% to 2.06% higher than an average voting ensemble.