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Carbonyl sulfide (OCS) is a toxic gas produced during industrial processes that poses risks to both human health and industrial equipment. Therefore, detecting OCS concentrations plays a crucial role in early hazard warning. This paper presents an online system for detecting OCS at the ppb level using thermal conversion and spectral reconstruction filtering differential optical absorption spectroscopy (SRF-DOAS). First, OCS, which is not suitable for DOAS due to its weak absorption characteristics, is completely transformed into SO2 with strong absorption characteristics under high-temperature conditions. Then, the spectral reconstruction filtering method (SRF) is proposed to eliminate the noise and interference. The core idea of the method is to arrange the spectrum according to the spectral intensity from small to large rather than wavelength, reconstructing the spectrum into a new spectrum with linear characteristics. The reconstructed spectrum can remove noise and interference by linear fitting and retain the characteristic of SO2 oscillation absorption. Next, we demonstrate the ability of the reconstructed spectral method to remove noise and interference by comparing the spectra of the inverse-reconstructed gas mixture and SO2. The relative deviation of 0.88% at 100 ppb and detection limit of 7.26 ppb*m for OCS were obtained using the SRF-DOAS method. Finally, the reliability of the system was confirmed by measurements of OCS concentrations in mixture gas of OCS and air, as well as in human exhaled breath.
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Luminescence thermometry is a promising non-contact temperature measurement technique, but improving the precision and reliability of this method remains a challenge. Herein, we propose a thermal sensing strategy based on a machine learning. By using Gd3Ga5O12: Er3+-Yb3+ as the sensing medium, a support vector machine (SVM) is preliminarily adopted to establish the relationship between temperature and upconversion emission spectra, and the sensing properties are discussed through the comparison with luminescence intensity ratio (LIR) and multiple linear regression (MLR) methods. Within a wide operating temperature range (303-853â K), the maximum and the mean measurement errors actualized by the SVM are just about 0.38 and 0.12â K, respectively, much better than the other two methods (3.75 and 1.37â K for LIR and 1.82 and 0.43â K for MLR). Besides, the luminescence thermometry driven by the SVM presents a high robustness, although the spectral profiles are distorted by the interferences within the testing environment, where, however, LIR and MLR approaches become ineffective. Results demonstrate that the SVM would be a powerful tool to be applied on the luminescence thermometry for achieving a high sensing performance.
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Sulfur compounds (SO2, CS2, H2S and OCS) are common toxic pollutants in the atmospheric environment, and the absorption spectroscopy technique can indeed help to realize online monitoring of their concentrations. However, nonlinear effects that occur during absorption spectroscopy measurements have a serious impact on the measurement of the absorption cross-sections (ACSs) of sulfur compounds, leading to serious deviations in both the substance absorption properties and concentrations obtained based on ACS analysis. In this paper, the maximum effective ACSs of sulfur compounds in the linear region are obtained by considering the influence of nonlinear effects and eliminating interference factors such as oxygen and photolysis. In addition, the nonlinear effects are found to be greatly attenuated in spectra with broad band absorption characteristics by comparing the oscillatory absorption spectra before and after the differential treatment and by comparing the change in the oscillatory ACS with the broad band ACS. The experimental results show that the effective ACSs of SO2, CS2, H2S, and OCS with a resolution of 0.23 nm are 14.15 × 10-18 cm2 per molecule, 5.61 × 10-16 cm2 per molecule, 7.09 × 10-18 cm2 per molecule, and 3.20 × 10-19 cm2 per molecule, respectively. So far, it is the largest ACS obtained at room temperature and atmospheric pressure, which is of great significance for online measurement of sulfur compounds.
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BACKGROUND: The goal was to explore the cognition of diagnosis and treatment level of IgG4-related diseases mainly involving lymph nodes. METHODS: The clinical manifestations, laboratory indicators, histopathology, and therapeutic effects of a patient with IgG4-RD suspected of lymphoma were analyzed and the relevant literature was reviewed. RESULTS: Lymph node biopsy showed reactive hyperplasia of lymph node tissue. The liver biochemical indexes were abnormal and the bone marrow smear showed atypical lymphocytes. Lymph node section: IgG4+ cells > 100/HPF (IgG4/IgG > 40%). The serum IgG4 level was 17,200 mg/L, and the diagnosis was IgG4-RD. Oral glucocorticoids took effect after 2 weeks, and no significant enlargement of lymph nodes was observed. CONCLUSIONS: For the diagnosis of IgG4-RD, at present, histopathology is still the gold standard, but a single result cannot diagnose the disease. Comprehensive judgment should be made by combining clinical symptoms, serum IgG4 level and imaging results to prevent misdiagnosis and missed diagnosis, and to avoid over-diagnosis. Short-term hormonal diagnostic therapy may be used in highly suspected patients who cannot be diagnosed. Once diagnosed, standardized medication, adhere to follow-up, regular review, to prevent recurrence and adverse drug reactions.
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Doença Relacionada a Imunoglobulina G4 , Imunoglobulina G , Hepatopatias , Humanos , Imunoglobulina G/sangue , Doença Relacionada a Imunoglobulina G4/diagnóstico , Doença Relacionada a Imunoglobulina G4/tratamento farmacológico , Doença Relacionada a Imunoglobulina G4/sangue , Hepatopatias/diagnóstico , Hepatopatias/imunologia , Hepatopatias/sangue , Glucocorticoides/uso terapêutico , Linfonodos/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
In this study, we determine the relationship between the broadband absorption spectroscopy and temperature using Doppler broadening combined with a multilinear shape superposition. First, a method for temperature effects on broadband absorption spectroscopy is proposed, utilizing the principle of a multiple Gaussian line shape superposition. A theoretical expression of the temperature effect on broadband spectroscopy is then presented for the first time to the best of our knowledge, and the variation law of broadband absorption spectroscopy with temperature is explained. Furthermore, the effectiveness of the expression is demonstrated by comparing experimental and theoretical data of the SO2 broadband absorption spectroscopy. The results demonstrate that the correlation coefficient (r) between the experimental and theoretical spectra of SO2 within the temperature range of 298.15-923.15â K is greater than 0.93. The method and expression presented in this Letter can effectively explain the data of previous research.
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BACKGROUND: The aim of the study was to improve the understanding of complex karyotype acute mixed cell leukemia containing pseudo Chediak-Higashi granules. METHODS: A case of acute mixed cell leukemia resembling AML1-ETO positive acute myeloid leukemia was reported. The results of morphological, immunophenotypic, and cytogenetic tests were analyzed by reviewing relevant literature. RESULTS: The patient was a young boy with clinical manifestations of recurrent fever. Bone marrow smear: Granulocyte system hyperplasia is obvious, visible at each stage, primitive cells account for 12%. These cells are large in volume, mostly round or class round, with abundant cell mass, stained gray blue, unbalanced development of some nuclear plasma, abnormal cytoplasmic staining, and visible "sunrise red" -like changes. Typical Auer bodies, pseudo Chadiak-Higashi granules and phagocytic erythroid substances were observed. The nuclei are irregular in shape, distorted and depressed, with fine chromatin and prominent large nucleoli. Bone marrow was extracted 3 days later, the bone marrow smear showed 65% primitive cells. The morphology of primitive cells was similar to that of 3 days ago. The results of flow cytometry showed that the primary/naive T cells in the samples possessed nuclear cells. Flow cytometry showed two groups of abnormal cells. One group accounted for 3.87% of nuclear cells and was a primitive/naive T-cell phenotype, mainly expressing: CD34+, CD7+, CD5+, CD2dim+, MPO-, CCD3 + part, CD3-, CD4-, CD8 -, CD117 -, CD13-, CD33-, HLA - DR -, CD10-, CD11b-, CD56-. The other group which accounted for 79.8% of the nuclear cells was monocyte phenotype, mainly expressing: CD34-, CD117-, CD13+ small amount, CD33+, HLA-DR-, CD11b+, CD14+, CD15+, CD36+, CD56+, CD64+, CD4+, CD85J+, CD85K + part. It matched the immunophenotype of acute mixed cell leukemia (T/MMPAL). Immunophenotypic leukemia-related fusion genes were negative, and karyotype analysis results were 45, XY, T (11; 12)(p13; Q13), -12-17, + mar [12]/90 < n > 4, idem x 2 [6]/46, XY. Combined with the above results, acute mixed cell leukemia was diagnosed. CONCLUSIONS: The flow cytometry is the gold standard in the diagnosis of acute mixed cell leukemia. The diagnosis of acute mixed cell leukemia requires the combination of clinical manifestations, cellular morphology, immunology, cytogenetics and molecular biology, and the comprehensive diagnosis efficiency is obviously better than that of morphology.
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Leucemia Aguda Bifenotípica , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Antígenos HLA-DR/análise , Medula Óssea/química , Fenótipo , Imunofenotipagem , Proteína 1 Parceira de Translocação de RUNX1/genética , Proteínas de Fusão Oncogênica/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genéticaRESUMO
Objective To investigate the clinicopathological features,immunohistochemical features,diagnosis,and relationship with sporadic prostate cancer in primary small cell neuroendocrine carcinoma of the bladder. Methods We retrospectively analyzed the clinical characteristics of 12 patients with primary small cell neuroendocrine carcinoma of the bladder diagnosed at Beijing Chao-Yang Hospital affiliated to Capital Medical University from January 2013 to September 2022.The histological features of primary small cell neuroendocrine carcinoma of the bladder were re-evaluated by two pathologists according to the 2022 revision of the World Health Organization Classification of Tumors of the Urinary System and Male Genital Organs.Electronic medical records were retrieved,and telephone follow-up was conducted from the time of histopathological diagnosis to the death or the end of the last follow-up until January 31,2023. Results The 12 patients include 7 patients in pT3 stage and 1 patient in pT4 stage.Eight patients were complicated with other types of tumors,such as high-grade urothelial carcinoma of the bladder and squamous cell carcinoma.Five patients had sporadic prostate cancer.Immunohistochemical staining showed that 12 (100.0%),10 (83.3%),and 8 (66.7%) patients were tested positive for CD56,Syn,and CgA,respectively.The Ki67 proliferation index ranged from 80% to 90%.Five patients with urothelial carcinoma were tested positive for CK20,GATA3,and CK7.P504S was positive in all the 5 patients with prostate cancer,while P63 and 34ßE12 were negative.The follow-up of the 12 patients lasted for 3-60 months.Eight of these patients died during follow-up,with the median survival of 15.5 months.Four patients survived. Conclusions Primary small cell neuroendocrine carcinoma of the bladder is a rare urological tumor with high aggressiveness and poor prognosis.In male patients with bladder prostatectomy,all prostate tissue should be sampled.If prostate cancer is detected,the prostate-specific antigen level should be monitored.
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Carcinoma Neuroendócrino , Carcinoma de Células de Transição , Neoplasias da Próstata , Neoplasias da Bexiga Urinária , Humanos , Masculino , Carcinoma de Células de Transição/patologia , Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/patologia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/metabolismo , Bexiga Urinária/patologia , Estudos Retrospectivos , Biomarcadores TumoraisRESUMO
High-sensitivity trace oxygen sensing based on far-ultraviolet absorption spectroscopy was realized. The far-ultraviolet absorption spectrum of oxygen in the wavelength range of 170-200 nm at normal pressure was measured, and the maximum oscillation absorption peak occurred close to 180.18 nm. Through error analysis, the optimal wavelength range for accurate and sensitive oxygen measurements by ultraviolet absorption spectroscopy was identified as 180-189 nm. A total column (CL) calibration curve for oxygen was established, and the maximum optical path length (L1) of the system was determined to be 0.75(3) m by comparing the oxygen absorption with and without the sample cell. The oxygen detection sensitivity was 232 m-1, and the lowest detection limit was 12 ppm at the L1 optical path length. The highly sensitive trace oxygen sensing based on far-ultraviolet absorption spectroscopy exhibited significant potential for application with regard to nitrogen protection.
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Luz , Oxigênio , Nitrogênio , Oxigênio/química , Espectrofotometria Ultravioleta/métodosRESUMO
Plant C2-domain abscisic acid-related (CAR) protein family plays an important role in plant growth, abiotic stress responses, and defense regulation. In this study, we cloned the IbCAR1 by homologous cloning method from the transcriptomic data of Xuzishu8, which is a sweet potato cultivar with dark-purple flesh. This gene was expressed in all tissues of sweet potato, with the highest expression level in leaf tissue, and it could be induced by NaCl and ABA. Subcellular localization analyses indicated that IbCAR1 was localized in the nucleus and plasma membrane. The PI staining experiment revealed the distinctive root cell membrane integrity of overexpressed transgenic lines upon salt stress. Salt stress significantly increased the contents of proline, ABA, and the activity of superoxide dismutase (SOD), whereas the content of malondialdehyde (MDA) was decreased in overexpressed lines. On the contrary, RNA interference plants showed sensitivity to salt stress. Overexpression of IbCAR1 in sweet potatoes could improve the salt tolerance of plants, while the RNAi of IbCAR1 significantly increased sensitivity to salt stress in sweet potatoes. Meanwhile, the genes involved in ABA biosynthesis, stress response, and reactive oxygen species (ROS)-scavenging system were upregulated in overexpressed lines under salt stress. Taken together, these results demonstrated that IbCAR1 plays a positive role in salt tolerance by relying on the ABA signal transduction pathway, activating the ROS-scavenging system in sweet potatoes.
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Ipomoea batatas , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/genéticaRESUMO
Stress-associated protein (SAP) genes-encoding A20/AN1 zinc-finger domain-containing proteins-play pivotal roles in regulating stress responses, growth, and development in plants. They are considered suitable candidates to improve abiotic stress tolerance in plants. However, the SAP gene family in sweetpotato (Ipomoea batatas) and its relatives is yet to be investigated. In this study, 20 SAPs in sweetpotato, and 23 and 26 SAPs in its wild diploid relatives Ipomoea triloba and Ipomoea trifida were identified. The chromosome locations, gene structures, protein physiological properties, conserved domains, and phylogenetic relationships of these SAPs were analyzed systematically. Binding motif analysis of IbSAPs indicated that hormone and stress responsive cis-acting elements were distributed in their promoters. RT-qPCR or RNA-seq data revealed that the expression patterns of IbSAP, ItbSAP, and ItfSAP genes varied in different organs and responded to salinity, drought, or ABA (abscisic acid) treatments differently. Moreover, we found that IbSAP16 driven by the 35 S promoter conferred salinity tolerance in transgenic Arabidopsis. These results provided a genome-wide characterization of SAP genes in sweetpotato and its two relatives and suggested that IbSAP16 is involved in salinity stress responses. Our research laid the groundwork for studying SAP-mediated stress response mechanisms in sweetpotato.
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Arabidopsis , Ipomoea batatas , Ipomoea , Ácido Abscísico/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/metabolismo , Hormônios/metabolismo , Ipomoea/genética , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Zinco/metabolismo , Dedos de Zinco/genéticaRESUMO
The saccharification of sweetpotato storage roots is a common phenomenon in the cooking process, which determines the edible quality of table use sweetpotato. In the present study, two high saccharified sweetpotato cultivars (Y25, Z13) and one low saccharified cultivar (X27) in two growth periods (S1, S2) were selected as materials to reveal the molecular mechanism of sweetpotato saccharification treated at high temperature by transcriptome sequencing and non-targeted metabolome determination. The results showed that the comprehensive taste score, sweetness, maltose content and starch change of X27 after steaming were significantly lower than those of Y25 and Z13. Through transcriptome sequencing analysis, 1918 and 1520 differentially expressed genes were obtained in the two periods of S1 and S2, respectively. Some saccharification-related transcription factors including MYB families, WRKY families, bHLH families and inhibitors were screened. Metabolic analysis showed that 162 differentially abundant metabolites related to carbohydrate metabolism were significantly enriched in starch and sucrose capitalization pathways. The correlation analysis between transcriptome and metabolome confirmed that the starch and sucrose metabolic pathways were significantly co-annotated, indicating that it is a vitally important metabolic pathway in the process of sweetpotato saccharification. The data obtained in this study can provide valuable resources for follow-up research on sweetpotato saccharification and will provide new insights and theoretical basis for table use sweetpotato breeding in the future.
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Metabolismo dos Carboidratos , Temperatura Alta , Ipomoea batatas/metabolismo , Raízes de Plantas/metabolismo , Transcriptoma , Manipulação de Alimentos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Metabolômica , Amido/metabolismo , Sacarose/metabolismoRESUMO
BACKGROUND: Purple-fleshed sweetpotato (PFSP) is one of the most important crops in the word which helps to bridge the food gap and contribute to solve the malnutrition problem especially in developing countries. Salt stress is seriously limiting its production and distribution. Due to lacking of reference genome, transcriptome sequencing is offering a rapid approach for crop improvement with promising agronomic traits and stress adaptability. RESULTS: Five cDNA libraries were prepared from the third true leaf of hexaploid sweetpotato at seedlings stage (Xuzi-8 cultivar) treated with 200 mM NaCl for 0, 1, 6, 12, 48 h. Using second and third generation technology, Illumina sequencing generated 170,344,392 clean high-quality long reads that were assembled into 15,998 unigenes with an average length 2178 base pair and 96.55% of these unigenes were functionally annotated in the NR protein database. A number of 537 unigenes failed to hit any homologs which may be considered as novel genes. The current results indicated that sweetpotato plants behavior during the first hour of salt stress was different than the other three time points. Furthermore, expression profiling analysis identified 4, 479, 281, 508 significantly expressed unigenes in salt stress treated samples at the different time points including 1, 6, 12, 48 h, respectively as compared to control. In addition, there were 4, 1202, 764 and 2195 transcription factors differentially regulated DEGs by salt stress at different time points including 1, 6, 12, 48 h of salt stress. Validation experiment was done using 6 randomly selected unigenes and the results was in agree with the DEG results. Protein kinases include many genes which were found to play a vital role in phosphorylation process and act as a signal transductor/ receptor proteins in membranes. These findings suggest that salt stress tolerance in hexaploid sweetpotato plants may be mainly affected by TFs, PKs, Protein Detox and hormones related genes which contribute to enhance salt tolerance. CONCLUSION: These transcriptome sequencing data of hexaploid sweetpotato under salt stress conditions can provide a valuable resource for sweetpotato breeding research and focus on novel insights into hexaploid sweetpotato responses to salt stress. In addition, it offers new candidate genes or markers that can be used as a guide to the future studies attempting to breed salt tolerance sweetpotato cultivars.
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Sequenciamento do Exoma/métodos , Perfilação da Expressão Gênica/métodos , Ipomoea batatas/fisiologia , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Ipomoea batatas/genética , Anotação de Sequência Molecular , Poliploidia , Estresse SalinoRESUMO
In this study, a sensitive system for simultaneous sensing of sulfur dioxide and carbon disulfide was developed based on absorption spectroscopy in the deep ultraviolet. An effective spectrum-unfolding approach is proposed to examine the overlapping spectral characteristics. Direct proportional relations with determination coefficients of 0.999 were obtained. The detection limit of sulfur dioxide was determined to be 42 ppb, and a detection limit of 5 ppb for carbon disulfide was achieved with an optical length of 20 cm. The interplay between the measurement results of the two components was investigated. Interference close to the detection limits was confirmed for both sulfur dioxide and carbon disulfide measurements. An automatic and reliable simultaneous sensing system for sulfur dioxide and carbon disulfide was constructed.
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This paper investigated a potential instrument for carbon disulfide in situ measurement with high precision and strong anti-interference capability. A compact and automated carbon disulfide detection system was developed using a fiber opto-electronic sensing device. A custom software interface based on LabVIEW was developed. The multi-wavelength least-squares method based on differential optical absorption spectroscopy was employed for improved detection and the anti-interference capabilities of the system. The detection limit of the system (signal-to-noise ratio=3) was determined to be 1 ppb per meter. Using this scheme, the reliability of a liquid-seal was verified to have carbon disulfide leakage. Although the liquid level of the liquid-sealed carbon disulfide showed no significant change over 24 h, a residue concentration of over 30 ppm remained detectable on the surface.
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We describe two mothers with metastatic gastric carcinoma involving the placenta. The first was a 35-year-old woman, who presented with a progressive decline in serum fibrinogen level at 34 + 2gestation week and underwent an emergency cesarean section. The second case was a 30-year-old woman who developed intolerable lumbosacral pain and cesarean section was performed at her 37 + 3gestation week. Gross pathological examinations of both placentas were normal, but microscopy showed poorly differentiated adenocarcinoma infiltration in the intervillous space, later proved to be gastric in origin. The neoplastic cells did not involve the villi, but were associated with massive perivillous fibrin. The two mothers died 180 and 19 days after the delivery. Both babies were free of metastatic carcinoma at 20- and 19-month follow-up.
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Adenocarcinoma/patologia , Doenças Placentárias/diagnóstico , Neoplasias Gástricas/patologia , Adenocarcinoma/diagnóstico , Adulto , Cesárea , Feminino , Fibrinogênio/metabolismo , Humanos , Metástase Neoplásica , Placenta/patologia , Gravidez , Complicações Neoplásicas na Gravidez/patologia , Resultado da Gravidez , Neoplasias Gástricas/diagnósticoRESUMO
OBJECTIVE: To observe and summarize the morphologic features that may suggest submucosal invasive adenocarcinoma in colorectal mucosa biopsy specimens. METHODS: The study cohort included 432 colorectal biopsy specimens were obtained from 2006 to 2012. All the cases had radical surgery. Basing on the pathologic diagnoses, the cases were divided into 366 invasive adenocarcinoma (IAC) and 66 high-grade intraepithelial neoplasms (HGIN). These two groups were compared. RESULTS: In the IAC group, the percentage of tumor forming cribriform structures, acute angle-shaped glands, diffuse carcinoma cell proliferation was 61.2% (224/366) , 33.8% (124/366) and 7.4% (27/366) , respectively. In the HGIN group, cribriform gland structures appeared in 6.0% (4/66) of the cases, while no acute angle-shaped gland or diffuse carcinoma cell proliferation was detected. The difference of these three characteristics in the two group was statistically significant (all P < 0.01). Glandular branching was detected in 89.9% (329/366) of IAC cases and 66.7% (44/66) of HGIN cases; this difference was not significant. There was no difference in cellular atypia between the two groups. Interstitial fibrosis was detected more frequently in the IAC group (85.5%, 313/366 in IAC versus 0 in HGIN, P < 0.01). In biopsy specimens of IAC, a few cases showed neoplastic glands in close contact with large lymphatics, adipose tissue, and ganglion. CONCLUSIONS: In colorectal biopsy specimen, the five features that suggest submucosal invasion of the neoplastic glands including the formation of cribriform structure, angular gland, diffuse carcinoma cells, interstitial fibrosis and neoplastic glands in close contact with the thick-walled vessels.
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Adenocarcinoma/patologia , Carcinoma in Situ/patologia , Mucosa Intestinal/patologia , Biópsia , Proliferação de Células , Diagnóstico Diferencial , Humanos , Invasividade NeoplásicaRESUMO
Accurate and efficient quantitative analysis of the decomposition products of the insulating medium SF6 in gas-insulated switchgear (GIS) is important for an effective assessment of its internal insulation status. In this work, a quantitative calibration model of Fourier Transform Infrared Spectroscopy (FTIR) combined with SCARS-DNN (Stability Competitive Adaptive Reweighted Sampling-Deep Neural Network) is proposed for the rapid non-destructive detection of SF6 decomposition products. First, the interference of the background gas SF6 on the absorption spectra of the decomposition products is eliminated according to the Lambert-Beer law, while baseline correction and Savitzky-Golay (S-G) smoothing are used to remove baseline drift and noise. Subsequently, a Monte Carlo cross-validation method is used to detect and eliminate the anomalous samples. Then feature selection is performed using uninformative variable elimination (UVE) and stability competitive adaptive reweighted sampling (SCARS), and finally quantitative calibration models of FULL-DNN (full spectral band), UVE-DNN, and SCARS-DNN are developed. For the quantitative detection of SF6 decomposition products, the SCARS-DNN model had the best prediction performance with a maximum reduction of 96.18% in the root mean square error (RMSE) and 96.11% in the mean absolute percentage error (MAPE). Results reveal that the relative errors are basically kept below 1.36% when predicting the three decomposition products, even in the presence of a high level of SF6 interference. Therefore, the SCARS-DNN model is suitable for high-precision quantitative detection of SF6 decomposition gas.
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OBJECTIVE: In this study, we propose a semi-supervised learning scheme using a patch-based deep learning framework to tackle the challenge of high-precision classification of seven lung tumor growth patterns, despite having a small amount of labeled data in whole slide images (WSIs). This scheme aims to enhance generalization ability with limited data and reduce dependence on large amounts of labeled data. It effectively addresses the common challenge of high demand for labeled data in medical image analysis. Approach. To address these challenges, the study employs a semi-supervised learning approach enhanced by a dynamic confidence threshold mechanism. This mechanism adjusts based on the quantity and quality of pseudo labels generated. This dynamic thresholding mechanism helps avoid the imbalance of pseudo-label categories and the low number of pseudo-labels that may result from a higher fixed threshold. Furthermore, the research introduces a multi-teacher knowledge distillation technique. This technique adaptively weights predictions from multiple teacher models to transfer reliable knowledge and safeguard student models from low-quality teacher predictions. Main results. The framework underwent rigorous training and evaluation using a dataset of 150 WSIs, each representing one of the seven growth patterns. The experimental results demonstrate that the framework is highly accurate in classifying lung tumor growth patterns in histopathology images. Notably, the performance of the framework is comparable to that of fully supervised models and human pathologists. In addition, the framework's evaluation metrics on a publicly available dataset are higher than those of previous studies, indicating good generalizability. Significance. This research demonstrates that a semi-supervised learning approach can achieve results comparable to fully supervised models and expert pathologists, thus opening new possibilities for efficient and cost-effective medical images analysis. The implementation of dynamic confidence thresholding and multi-teacher knowledge distillation techniques represents a significant advancement in applying deep learning to complex medical image analysis tasks. This advancement could lead to faster and more accurate diagnoses, ultimately improving patient outcomes and fostering the overall progress of healthcare technology. .
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Ammonia (NH3) in exhaled breath (EB) has been a biomarker for kidney function, and accurate measurement of NH3 is essential for early screening of kidney disease. In this work, we report an optical sensor that combines ultraviolet differential optical absorption spectroscopy (UV-DOAS) and spectral reconstruction fitting neural network (SRFNN) for detecting NH3 in EB. UV-DOAS is introduced to eliminate interference from slow change absorption in the EB spectrum while spectral reconstruction fitting is proposed for the first time to map the original spectra onto the sine function spectra by the principle of least absolute deviations. The sine function spectra are then fitted by the least-squares method to eliminate noise signals and the interference of exhaled nitric oxide. Finally, the neural network is built to enable the detection of NH3 in EB at parts per billion (ppb) level. The laboratory results show that the detection range is 9.50-12425.82 ppb, the mean absolute percentage error (MAPE) is 0.83%, and the detection accuracy is 0.42%. Experimental results prove that the sensor can detect breath NH3 and identify EB in simulated patients and healthy people. Our sensor will serve as a new and effective system for detecting breath NH3 with high accuracy and stability in the medical field.
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Amônia , Testes Respiratórios , Redes Neurais de Computação , Amônia/análise , Testes Respiratórios/métodos , Testes Respiratórios/instrumentação , Humanos , Espectrofotometria Ultravioleta/métodos , ExpiraçãoRESUMO
The concentration of fractional exhaled nitric oxide (FeNO) is closely related to human respiratory inflammation, and the detection of its concentration plays a key role in aiding diagnosing inflammatory airway diseases. In this paper, we report a gas sensor system based on a distributed parallel self-regulating neural network (DPSRNN) model combined with ultraviolet differential optical absorption spectroscopy for detecting ppb-level FeNO concentrations. The noise signals in the spectrum are eliminated by discrete wavelet transform. The DPSRNN model is then built based on the separated multipeak characteristic absorption structure of the UV absorption spectrum of NO. Furthermore, a distributed parallel network structure is built based on each absorption feature region, which is given self-regulating weights and finally trained by a unified model structure. The final self-regulating weights obtained by the model indicate that each absorption feature region contributes a different weight to the concentration prediction. Compared with the regular convolutional neural network model structure, the proposed model has better performance by considering the effect of separated characteristic absorptions in the spectrum on the concentration and breaking the habit of bringing the spectrum as a whole into the model training in previous related studies. Lab-based results show that the sensor system can stably achieve high-precision detection of NO (2.59-750.66 ppb) with a mean absolute error of 0.17 ppb and a measurement accuracy of 0.84%, which is the best result to date. More interestingly, the proposed sensor system is capable of achieving high-precision online detection of FeNO, as confirmed by the exhaled breath analysis.