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OBJECTIVE: This longitudinal study aims to examine the present state of perceived control, self-management efficacy, and overall quality of life (QoL) in patients with breast cancer undergoing radiotherapy, and gain insight into the dynamic trends and factors that influence the quality of life experienced by patients during the course of radiotherapy. METHODS: Participants completed the Cancer Experience and Efficacy Scale (CEES), Strategies Used by People to Promote Health (SUPPH), and Functional Assessment of Cancer Therapy- Breast (FACT-B). The data was analyzed using the software SPSS26.0. Repeated measures analysis of variance (ANOVA) and mixed-effects linear models were used to analyze trends in perceived control, self-management efficacy, and QoL at three-time points, as well as factors affecting QoL during radiotherapy. RESULTS: Perceived control and self-management efficacy were associated with QoL over the course of the radiotherapy. Self-management efficacy (ß = 0.30, P < 0.001), presence of chemotherapy (ß = 18.33, P = 0.024), and duration of illness (ß = 2.25, P = 0.028) had a positive effect on the change in QoL, while time (ß = - 2.95, P < 0.001), cancer experience (ß = - 0.46, P < 0.001), and type of medical insurance (ß = - 2.77, P = 0.021) had the negative effect on the change in QoL. CONCLUSION: The QoL, perceived control, and self-efficacy of patients with breast cancer show dynamic changes during radiotherapy. The higher the self-efficacy, the better the QoL, and the worse the QoL when the sense of disease control is poor. At the same time, more attention should be paid to the QoL of breast cancer radiotherapy patients with a long course of the disease, receiving chemotherapy, and different medical payment methods.
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Neoplasias da Mama , Autogestão , Humanos , Feminino , Neoplasias da Mama/radioterapia , Qualidade de Vida , Estudos Longitudinais , Promoção da Saúde , AutoeficáciaRESUMO
Imaging of electronic device surface or sub-surface electromagnetic fields under operating conditions is important for device design and diagnosis. In this study, we proposed a method to characterize specific magnetic field properties of electromagnetic devices at micron-scale using a solid-state quantum sensor, namely diamond nitrogen-vacancy (NV) centers. By employing a wide-field magnetic field measurement technique based on NV centers, we rapidly obtain the first-order magnetic field distribution of anomalous regions. Furthermore, we approximate the second-order magnetic field (magnetic gradient tensor) using the differential gradient method. To visualize the electromagnetic anomalous regions boundary, we utilize the tensor invariants of the magnetic gradient tensor components, along with their nonlinear combinations. The identification error rate of the anomalous regions is within 12.5%. Additionally, the electromagnetic field of anomalous regions is simulated showing the measurement accuracy. Our study shows that the experimental results are very similar to the theoretical simulation of the electromagnetic field (error: 7%). This work is essential for advancing electromagnetic field characterization of electronic devices and the advancement of quantum magnetic sensor applications.
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In this paper, we propose a method for simultaneously recovering multiple radio wave signals based on nitrogen-vacancy (NV) centers in diamond combining optically detected magnetic resonance (ODMR) spectrum. A controlled magnetic field gradient applied to the laser excitation area on the surface of diamond widens the detectable ODMR bandwidth to 200â MHz. Three different frequency-modulated (FM) signals with distinct carrier frequencies falling within the resonance frequency range are received and demodulated in real-time. Subsequently, the FM signal reception capability of this system is further investigated by measuring baseband signal frequencies ranging from 0.1â Hz to 200â Hz and adjusting the carrier power within a dynamic range from -10 dBm to 30 dBm. This proposal, which accomplishes multi-channel demodulation using a compact and single device, has potential applications in fields such as wireless communication, radar and navigation.
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A 66-year-old neurofibromatosis type 1 (NF1) patient with polyarticular pain for nine years, aggravated for two days, was transferred from the Emergency Intensive Care Unit (EICU) to our rheumatology department. She was diagnosed with NF1 nine years ago by a gene mutation detection and coronary heart disease (CHD) three months ago. The patient was diagnosed with rheumatoid arthritis (RA) this time. After 24 days of treatment with appropriate medication, the patient was discharged with relieved joint pain. However, about four months later, the patient died of circulatory failure caused by myocardial infarction. We analyzed the possible reasons for her outcome and made a review of the literature. There are few clinical reports of NF1 complicated with RA. We found five cases reported in the literature up to date during our search and included them in our communication to compare with our case. NF1 combined with RA mainly affects adult women and usually starts with NF1 and is followed by RA after at least six years of NF1 symptom onset. Although the summarized characteristics of clinical and potential pathogenesis of NF1 combined with RA were limited with these six cases, we hope that this will help clinicians to increase their understanding of this rare complication, thus helping to guide clinical medication.
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Accessory navicular (AN) is a developmental variation of the secondary ossification center of the navicular tuberosity. Ten percent of patients with AN will have pain symptoms that affect walking and life. As the AN changes the position of the posterior tibial tendon insertion, children with AN often have posterior tibial tendon function insufficiency and flexible flat foot. Surgical treatment is often required after failure of conservative treatment. This article reviewed the etiology, clinical manifestations, complications, and treatment methods of AN.
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BACKGROUND: Many methodologies for selecting histopathological images, such as sample image patches or segment histology from regions of interest (ROIs) or whole-slide images (WSIs), have been utilized to develop survival models. With gigapixel WSIs exhibiting diverse histological appearances, obtaining clinically prognostic and explainable features remains challenging. Therefore, we propose a novel deep learning-based algorithm combining tissue areas with histopathological features to predict cancer survival. METHODS: The Cancer Genome Atlas Colon Adenocarcinoma (TCGA-COAD) dataset was used in this investigation. A deep convolutional survival model (DeepConvSurv) extracted histopathological information from the image patches of nine different tissue types, including tumors, lymphocytes, stroma, and mucus. The tissue map of the WSIs was segmented using image processing techniques that involved localizing and quantifying the tissue region. Six survival models with the concordance index (C-index) were used as the evaluation metrics. RESULTS: We extracted 128 histopathological features from four histological types and five tissue area features from WSIs to predict colorectal cancer survival. Our method performed better in six distinct survival models than the Whole Slide Histopathological Images Survival Analysis framework (WSISA), which adaptively sampled patches using K-means from WSIs. The best performance using histopathological features was 0.679 using LASSO-Cox. Compared to histopathological features alone, tissue area features increased the C-index by 2.5%. Based on histopathological features and tissue area features, our approach achieved performance of 0.704 with RIDGE-Cox. CONCLUSIONS: A deep learning-based algorithm combining histopathological features with tissue area proved clinically relevant and effective for predicting cancer survival.
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Adenocarcinoma , Neoplasias do Colo , Aprendizado Profundo , Humanos , Algoritmos , Processamento de Imagem Assistida por ComputadorRESUMO
Single-atom catalysis of carbon monoxide oxidation on metal-oxide surfaces is crucial for greenhouse recycling, automotive catalysis, and beyond, but reports of the atomic-scale mechanism are still scarce. Here, using scanning probe microscopy, we show that charging single gold atoms on oxidized rutile titanium dioxide surface, both positively and negatively, considerably promotes adsorption of carbon monoxide. No carbon monoxide adsorption is observed on neutral gold atoms. Two different carbon monoxide adsorption geometries on gold atoms are identified. We demonstrate full control over the redox state of adsorbed gold single atoms, carbon monoxide adsorption geometry, and carbon monoxide adsorption/desorption by the atomic force microscopy tip. On charged gold atoms, we activate Eley-Rideal oxidation reaction between carbon monoxide and a neighboring oxygen adatom by the tip. Our results provide unprecedented insights into carbon monoxide adsorption and suggest that the gold dual activity for carbon monoxide oxidation after electron or hole attachment is also the key ingredient in photocatalysis under realistic conditions.
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Paraffin and octadecyltrichlorosilane (OTS) coatings can alleviate collisions between alkali-metal atoms and cell walls and then prolong the atomic spin-polarization lifetime. The surface structure and collision effects of these antirelaxation coatings, as well as the methods to avoid antirelaxation invalidity, have been the focus of researchers. This study investigated the thermolability of coating surface structure and the collision interactions between alkali metal atoms and coatings, considering the influence of various coating preparation factors, where this collision interaction is indirectly analyzed by measuring the collision energy dissipation between an atomic force microscopy (AFM) probe and the atoms on the coating surface. We found that appropriate evaporation time, carbochain length, and postannealing process can enhance the thermostability of the paraffin coating and eliminate its morphological defects. Furthermore, the OTS/water concentration, the soaking time, and the type of solvent have different levels of influence on the cluster formation and the thermostability of the OTS coatings. Moreover, the antirelaxation performance of coatings has been shown to be characterized by counting the energy dissipated when the AFM probe collides with the antirelaxation coating, replacing the conventional light-atom interaction- based method for measuring the relaxation characteristics, but requiring specific coating preparation factors to be maintained.
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Acetylcholinesterase (AChE) is an important therapeutic target for the treatment of Alzheimer's disease (AD), and the development of natural AChE inhibitors as candidates has played a significant role in drug discovery. In this study, the inhibition mechanisms of four ellagitannins, punicalagin, chebulinic acid, geraniin and corilagin, from Terminalia chebula fruits on AChE were investigated systematically by a combination of inhibition kinetics, multi-spectroscopic methods and molecular docking. The kinetic results showed that punicalagin, chebulinic acid and geraniin exhibited strong reversible inhibitory effects on AChE in an uncompetitive manner with the IC50 values of 0.43, 0.50, and 0.51 mM, respectively, while corilagin inhibited AChE activity in a mixed type with the IC50 value of 0.72 mM. The results of fluorescence and UV-vis spectra and fluorescence resonance energy transfer (FRET) revealed that four ellagitannins could significantly quenched the intrinsic fluorescence of AChE though a static quenching along with non-radiative energy transfer. Thermodynamic analyses showed that values of ΔG, ΔH and ΔS were negative, indicating that all binding processes were spontaneous, and the hydrogen bonding and Van der Waals forces might make a great contribution to the formation of inhibitor-AChE complexes. The synchronous fluorescence, three-dimensional (3D) fluorescence, UV-vis, and FT-IR spectra studies suggested that four ellagitannins could lead to alterations in the micro-environment and secondary structure of AChE, and thus the conformational change of AChE. Moreover, molecular docking demonstrated that four ellagitannins could interacted with main amino acid residues of AChE with affinity energies ranging from -9.9 to -8.7 kJ/mol, and further confirmed the above experimental results. This study provided valuable findings for the potential application of four ellagitannins as promising candidates in the exploration of natural AChE inhibitors for the treatment of AD.
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Taninos Hidrolisáveis , Terminalia , Simulação de Acoplamento Molecular , Taninos Hidrolisáveis/metabolismo , Acetilcolinesterase/metabolismo , Terminalia/metabolismo , Ligação Proteica , Sítios de Ligação , Espectroscopia de Infravermelho com Transformada de Fourier , Frutas/metabolismo , CinéticaRESUMO
CD8 + T cells are essential for long-lasting HIV-1 control and have been harnessed to develop therapeutic and preventive approaches for people living with HIV-1 (PLWH). HIV-1 infection induces marked metabolic alterations. However, it is unclear whether these changes affect the anti-HIV function of CD8 + T cells. Here, we show that PLWH exhibit higher levels of plasma glutamate than healthy controls. In PLWH, glutamate levels positively correlate with HIV-1 reservoir and negatively correlate with the anti-HIV function of CD8 + T cells. Single-cell metabolic modeling reveals glutamate metabolism is surprisingly robust in virtual memory CD8 + T cells (TVM). We further confirmed that glutamate inhibits TVM cells function via the mTORC1 pathway in vitro. Our findings reveal an association between metabolic plasticity and CD8 + T cell-mediated HIV control, suggesting that glutamate metabolism can be exploited as a therapeutic target for the reversion of anti-HIV CD8 + T cell function in PLWH.
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Infecções por HIV , HIV-1 , Humanos , Ácido Glutâmico , Linfócitos T CD8-Positivos , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologiaRESUMO
Liver cancer stem-like cells (LCSCs) are the main cause of heterogeneity and poor prognosis in hepatocellular carcinoma (HCC). In this study, we aimed to explore the origin of LCSCs and the role of the TOP2A/ß-catenin/YAP1 axis in tumor stemness and progression. Using single-cell RNA-seq analysis, we identified TOP2A+CENPF+ LCSCs, which were mainly regulated by CD168+ M2-like macrophages. Furthermore, spatial location analysis and fluorescent staining confirmed that LCSCs were enriched at tumor margins, constituting the spatial heterogeneity of HCC. Mechanistically, TOP2A competitively binds to ß-catenin, leading to disassociation of ß-catenin from YAP1, promoting HCC stemness and overgrowth. Our study provides valuable insights into the spatial transcriptome heterogeneity of the HCC microenvironment and the critical role of TOP2A/ß-catenin/YAP1 axis in HCC stemness and progression.
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Using water treatment sludge and lanthanum chloride as raw materials, lanthanum-modified water treatment sludge hydrothermal carbon was prepared through one-step hydrothermal carbonization and loading lanthanum. SEM-EDS, BET, FTIR, XRD, and XPS were used to characterize the materials. The initial pH of the solution, adsorption time, adsorption isotherm, and adsorption kinetics were investigated to study the adsorption characteristics of phosphorus in water. The results showed that the specific surface area, the pore volume, and the pore size of the prepared materials were significantly increased, and the phosphorus adsorption capacity was greatly improved compared with that of the water treatment sludge. The adsorption process conformed to the pseudo-second-order kinetic model, and the Langmuir model fitted the maximum phosphorus adsorption capacity to 72.69 mg·g-1. The main adsorption mechanisms were electrostatic attraction and ligand exchange. Adding lanthanum-modified water treatment sludge hydrochar into the sediment could effectively control the release of endogenous phosphorus from the sediment to the overlying water. According to the analysis of phosphorus forms in sediment, the addition of hydrochar promoted the transformation of unstable NH4Cl-P, BD-P and Org-P into the very stable HCl-P in the sediment, which reduced the content of potential active phosphorus and also significantly reduced the content of biologically available phosphorus. This indicated that lanthanum-modified water treatment sludge hydrochar could effectively adsorb and remove phosphorus in water and could also be used as sediment improvement material to effectively stabilize endogenous phosphorus in sediment and control phosphorus content in water.
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An imbalance of l-tryptophan (l-Trp), a basic component of a healthy diet, is harmful to human health. Traditional methods for detecting l-Trp have many limitations. To correct a deficiency or excess of l-Trp in human diets, it is necessary to develop a novel method that is rapid, low-cost, and high-sensitivity. Herein, a molecularly imprinted polysaccharide electrochemical sensor termed MIP/CS/MWCNTs/GCE (molecularly imprinted polymer/chitosan/multiwalled carbon nanotubes/glassy carbon electrode) targeting l-Trp was first constructed on a glassy carbon electrode, which was modified with multiwalled carbon nanotubes and chitosan using bifunctional monomers. The MIP/CS/MWCNTs/GCE obtained a wide linear range (1-300 µM) for detecting l-Trp and accurately detected the proportion of l-Trp in mixtures of Trp enantiomers. In milk samples, the spiked recoveries of l-Trp were 86.50 to 99.65%. The MIP/CS/MWCNTs/GCE electrochemical sensor possessed good recognition and detection performance for l-Trp and has promising potential for practical application.
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Quitosana , Impressão Molecular , Nanotubos de Carbono , Humanos , Impressão Molecular/métodos , Polímeros , Triptofano , Técnicas Eletroquímicas/métodos , Eletrodos , Dieta , Limite de DetecçãoRESUMO
OBJECTIVES: To survey the development status and actual needs of virtual autopsy technology in China and to clarify the applicability of forensic virtual autopsy laboratory accreditation. METHODS: The questionnaire was set up included three aspectsï¼(1) the current status of virtual autopsy technology development; (2) the accreditation elements such as personnel, equipment, entrustment and acceptance, methods, environmental facilities; (3) the needs and suggestions of practicing institutions. A total of 130 forensic pathology institutions were surveyed by online participation through the Questionnaire Star platform. RESULTS: Among the 130 institutions, 43.08% were familiar with the characteristics of virtual autopsy technology, 35.38% conducted or received training in virtual autopsy, and 70.77% have establishment needs (including maintenance). Relevant elements were suitable for laboratory accreditation. CONCLUSIONS: Virtual autopsy identification has gained social recognition. There is a demand for accreditation of forensic virtual autopsy laboratory. After the preliminary assessment, considering the characteristics and current situation of this technology, China National Accreditation Service for Conformity Assessment (CNAS) can first carry out the accreditation pilot of virtual autopsy project at large comprehensive forensic institutions with higher identification capability, and then CNAS can popularize the accreditation in a wide range when the conditions are suitable.
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Autopsia , Patologia Legal , Laboratórios , Medicina Legal , Acreditação , Laboratórios/normas , ChinaRESUMO
Aims: Gut-microbiome derived short-chain fatty acids exert anti-inflammatory effects and delay progression of kidney disease in diabetic nephropathy. The aim of this study was to examine the impact in vivo and in vitro of short-chain fatty acid treatment on cellular pathways involved in the development of experimental diabetic nephropathy. Methods: To determine the effect of short-chain fatty acids in diabetic nephropathy, we compared wildtype, GPR43-/- and GPR109A-/- mice diabetic mice treated with acetate or butyrate and assessed variables of kidney damage. We also examined the impact of short-chain fatty acid treatment on gene expression in renal tubular cells and podocytes under high glucose conditions. Results: Short-chain fatty acid treatment with acetate or butyrate protected wild-type mice against development of diabetic nephropathy, exhibiting less glomerular hypertrophy, hypercellularity and interstitial fibrosis compared to diabetic controls. Acetate and butyrate treatment did not provide the same degree of protection in diabetic GPR43-/- and GPR109A-/- diabetic mice respectively. Consistent with our in vivo results, expression of pro-inflammatory genes in tubular epithelial cells exposed to high glucose were attenuated by acetate and butyrate treatment. Acetate did not reduce inflammatory or fibrotic responses in glucose stimulated GPR43-/- TECs. Butyrate mediated inhibition of pro-fibrotic gene expression in TECs through GPR109A, and in podocytes via GPR43. Conclusion: SCFAs protect against progression of diabetic nephropathy and diminish podocyte and tubular epithelial injury and interstitial fibrosis via direct, GPR-pathway dependent effects on intrinsic kidney cells. GPR43 and GPR109A are critical to short-chain fatty acid mediated reno-protection and have potential to be harnessed as a therapeutic target in diabetic nephropathy.
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This study aims to explore the effect of Buyang Huanwu Decoction glycosides on the inflammatory response of apolipoprotein E~(-/-)(ApoE~(-/-)) mice and RAW264.7 cells through nuclear factor kappa-B(NF-κB) signaling pathway. In the in vivo experiment, ApoE~(-/-) mice were fed with high-fat diets for 12 weeks to induce the animal model of atherosclerosis, and 75 µg·mL~(-1) oxidized low-density lipoprotein(Ox-LDL) incubated RAW264.7 cells for 24 h to establish the atherosclerosis cell model. Automatic biochemical analyzer, hematoxylin-eosin(HE) staining, enzyme-linked immunosorbent assay(ELISA), Western blot, and droplet digital polymerase chain reaction(PCR) were used to determine the blood lipid levels, aortic intimal thickness, inflammatory factor content, NF-κB pathway-related proteins, and mRNA expression levels, and evaluate arterial atherosclerotic lesions and anti-atherosclerotic mechanisms of the drug. The model of atherosclerosis was successfully established in ApoE~(-/-) mice after 12 weeks of feeding with high-fat diets. In the model group, the plasma levels of total cholesterol(TC), triglyceride(TG), and low-density lipoprotein cholesterol(LDL-C) were increased(P<0.01), the intima of the blood vessels was thickened, the levels of inflammatory factors tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) were increased, and the protein and mRNA expressions of NF-κB and inhibitor of NF-κB(IκBα) were significantly increased as compared with the control group. Compared with the model group, the high-dose Buyang Huanwu Decoction glycoside group decreased the plasma levels of TC, TG, and LDL-C, reduced the plaque area and thickness and the content of inflammatory factor TNF-α, and inhibited the protein and mRNA expressions of NF-κB and IκBα, with the effect same as Buyang Huanwu Decoction. In the in vivo experiment, 75 µg·mL~(-1) Ox-LDL stimulated RAW264.7 cells for 24 h to successfully establish a foam cell model. As compared with the control group, the nuclear amount of NF-κB and the protein and mRNA expressions of IκBα in the model group increased. Compared with the model group, the middle-dose and high-dose Buyang Huanwu Decoction glycoside groups decreased the nuclear amount of NF-κB and the protein and mRNA expressions of IκBα. The above results show that the glycosides are the main effective substances of Buyang Huanwu Decoction against atherosclerosis, which inhibit the NF-κB pathway and reduce the inflammatory response, thus playing the role against atherosclerotic inflammation same as Buyang Huanwu Decoction.
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Aterosclerose , NF-kappa B , Camundongos , Animais , NF-kappa B/genética , NF-kappa B/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Glicosídeos/farmacologia , LDL-Colesterol , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Transdução de Sinais , Inflamação/tratamento farmacológico , Interleucina-6 , Apolipoproteínas E/genética , Apolipoproteínas E/farmacologia , RNA Mensageiro/metabolismoRESUMO
The recently proposed high-low Kelvin probe force microscopy (KPFM) enables evaluation of the effects of semiconductor interface states with high spatial resolution using high and low AC bias frequencies compared with the cutoff frequency of the carrier transfer between the interface and bulk states. Information on the energy spectrum of the interface state density is important for actual semiconductor device evaluation, and there is a need to develop a method for obtaining such physical quantities. Here, we propose high-low Kelvin probe force spectroscopy (high-low KPFS), an electrostatic force spectroscopy method using high- and low-frequency AC bias voltages to measure the interface state density inside semiconductors. We derive an analytical expression for the electrostatic forces between a tip and a semiconductor sample in the accumulation, depletion, and inversion regions, taking into account the charge transfer between the bulk and interface states in semiconductors. We show that the analysis of electrostatic forces in the depletion region at high- and low-frequency AC bias voltages provides information about the interface state density in the semiconductor bandgap. As a preliminary experiment, high-low KPFS measurements were performed on ion-implanted silicon surfaces to confirm the dependence of the electrostatic force on the frequency of the AC bias voltage and obtain the interface state density.
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We propose hybrid phase modulation (PM)/frequency modulation (FM) atomic force microscopy (AFM) to increase the imaging speed of AFM in high-Q environments. We derive the relationship between the phase shift, the frequency shift and the tip-sample interaction force from the equation of motion for the cantilever in high-Q environments. The tip-sample conservative force is approximately given by the sum of the conservative force with respect to the phase shift in the PM mode and that with respect to the frequency shift in the FM mode. We preliminarily demonstrate that the hybrid PM/FM-AFM is a new and very promising AFM operation mode that can increase imaging speed.
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Microscopia de Força Atômica , Microscopia de Força Atômica/métodosRESUMO
To estimate the incidence of foodborne gastroenteritis caused by nontyphoidal Salmonella enterica, Shigella, and Vibrio parahaemolyticus in China, population surveys and sentinel hospital surveillance were implemented in six provinces from July 2010 to July 2011, and a multiplier calculation model for the burden of disease was constructed. The multiplier for salmonellosis and V. parahaemolyticus gastroenteritis was estimated at 4,137 [95% confidence interval (CI) 2,320-5,663], and for shigellosis at 4,356 (95% CI 2,443-5,963). Annual incidence per 100,000 population was estimated as 245 (95% CI 138-336), 67 (95% CI 38-92), and 806 (95% CI 452-1,103) for foodborne salmonellosis, shigellosis, and V. parahaemolyticus gastroenteritis, respectively, indicating that foodborne infection caused by these three pathogens constitutes an important burden to the Chinese healthcare system. Continuous implementation of active surveillance of foodborne diseases, combined with multiplier models to estimate disease burden, makes it possible for us to better understand food safety status in China.
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Disenteria Bacilar , Doenças Transmitidas por Alimentos , Gastroenterite , Intoxicação Alimentar por Salmonella , Infecções por Salmonella , Salmonella enterica , Shigella , Vibrio parahaemolyticus , Humanos , Disenteria Bacilar/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Gastroenterite/epidemiologia , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologia , China/epidemiologiaRESUMO
Surface photovoltage (SPV) measurements are a crucial way of investigating optoelectronic and photocatalytic semiconductors. The local SPV is generally measured consecutively by Kelvin probe force microscopy (KPFM) in darkness and under illumination, in which thermal drift degrades spatial and energy resolutions. In this study, we propose the method of AC bias Kelvin probe force microscopy (AC-KPFM), which controls the AC bias to nullify the modulated signal. We succeeded in directly measuring the local SPV by AC-KPFM with higher resolution, thanks to the exclusion of the thermal drift. We found that AC-KPFM can achieve a SPV response faster by about one to eight orders of magnitude than classical KPFM. Moreover, AC-KPFM is applicable in both amplitude modulation and frequency modulation mode. Thus, it contributes to advancing SPV measurements in various environments, such as vacuum, air, and liquids. This method can be utilized for direct measurements of changes in surface potential induced by modulated external disturbances.