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Objective: To investigate the clinical and pathologic features, diagnosis and differential diagnosis of hypertrophic port-wine stain (PWS). Methods: Cases of hypertrophic PWS, collected from Henan Provincial People's Hospital between 2012 and 2018, were retrospectively analyzed for their clinical and pathologic features, immunophenotype and histochemical data, and the relevant literature was reviewed. Results: Twenty-four cases of PWS were included in this cohort, located in the head and neck region (20 cases), limbs (2 cases), and trunk (2 cases). The clinical presentations were mainly red or purple-red plaques or slow growing, painless nodules, or thickened and raised above the skin surface. Microscopically, deformed blood vessels showed honeycomb-like, plexiform or cluster-like growth pattern, and diffusely involved the dermis, skin appendages, subcutaneous fat tissue, and deep skeletal muscles; The vascular lumen of the deformed vessels was dilated (≥100 µm in diameter), and in 18 cases the lumen was greater than 400 µm. The superficial dermis mainly contained few deformed capillaries. The deep wall showed thickening of blood vessel wall and fibrous tissue hyperplasia. Elastic fiber and Masson staining indicated abnormal venous vessel, which in some cases contained small amount of abnormal arterioid vessel,without vascular endothelial cell proliferation in all cases. In 24 cases, 19 cases had epidermal atrophy, 6 with vascular chronic inflammation or epidermal ulcer, 4 with capillary hemangioma, 4 with sebaceous gland hyperplasia, 2 with epidermal papillary hyperplasia and 2 with vascular keratomas. Conclusions: PWS is a common congenital capillary malformation. The number of histologically deformed capillaries is reduced and they usually locate in the superficial part. The deep vascular wall is increased with thick venous malformation, diffusely involving the dermis and deep skeletal muscle. Furthermore, PWS needs to be differentiated from infantile hemangioma, cavernous hemangioma and vascular keratomas.
Assuntos
Mancha Vinho do Porto/patologia , Pele/patologia , Humanos , Estudos RetrospectivosRESUMO
BACKGROUND: Phenoxyethanol is a widely used preservative in personal care products. Transient receptor potential vanilloid 1 (TRPV1) on cell membrane is activated by TRPV1 agonist capsaicin resulting in an opening of the channel for calcium influx, which is linked with neurosensory sensations characterized by itching, burning and stinging of skin. Whether uncomfortable skin sensations caused by phenoxyethanol claimed by people having sensitive skin are also due to activation of TRPV1 has not been reported in the literature. OBJECTIVE: The aim of this study was to evaluate whether the TRPV1 is involved in the induction of itching and burning sensation by phenoxyethanol. METHODS AND MATERIALS: The effect of phenoxyethanol on TRPV1 was assessed in vitro on HaCaT cells. The activation of TRPV1 and its inhibition by a TRPV1 antagonist were evaluated by cellular calcium influx. TRPV1 protein expression was also investigated by Western blot. In vivo in a split-face study, phenoxyethanol formulated at 1% was compared to a formulation additionally containing a TRPV1 antagonist. By applying the formulations to the nasolabial fold, the scores of phenoxyethanol-induced sensations were compared to those of the TRPV1 antagonist. RESULTS: In vitro phenoxyethanol induced calcium influx in HaCaT cells in a dose-dependent manner after 20 min. This effect was abolished by a solution containing the TRPV1 antagonist trans-tert-butyl cyclohexanol (ID1609). Phenoxyethanol had no effect on the expression of TRPV1, whereas capsaicin caused a significant downregulation of this receptor in the same experiment. In vivo 1% phenoxyethanol induced a skin burning and itching sensation in a cohort of 60 of 243 Chinese female subjects being sensitive to phenoxyethanol discomfort. The uncomfortable skin sensations were significantly inhibited by ID1609. CONCLUSIONS: Different to capsaicin, phenoxyethanol did not downregulate the expression of TRPV1 in HaCaT cells, suggesting that different regulatory mechanisms may exist for capsaicin and phenoxyethanol. Our experiments demonstrated that phenoxyethanol induces skin misperception and uncomfortable skin sensations like itching and burning comparable to capsaicin via activating TRPV1. The stimulation was inhibited by blocking TRPV1 with ID1609. The present data strengthened hitherto studies that TRPV1 plays a critical role in sensitive skin.
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Etilenoglicóis/administração & dosagem , Irritantes/administração & dosagem , Canais de Cátion TRPV/antagonistas & inibidores , Animais , Cálcio/metabolismo , Linhagem Celular , Método Duplo-Cego , Feminino , Humanos , Técnicas In Vitro , PlacebosRESUMO
Deregulation of cardiac miRNA gene-regulatory networks is a feature of different heart diseases, including ischemic (ICM) and nonischemic (NICM) cardiomyopathy. Here, based on the paired miRNA and mRNA expression profiles in ICM and NICM, we identified the differentially expressed miRNAs and mRNAs and the expression signatures distinguishing ICM/NICM from control samples. Furthermore, we constructed a functional miRNA network for each disease. Analysis of the topological features of these networks revealed that the Wnt signaling pathway and cell cycle (de)regulation play critical roles in the development of ICM and NICM. In addition, comparison of the miRNA and mRNA functional profiles revealed that their expression patterns in ICM and NICM differ. These findings revealed hundreds of novel heart-failure-related miRNAs with important regulatory functions. In summary, RNA-seq-based transcriptome profiling in the failing human heart revealed a complex transcriptional regulation associated with the disease. The newly uncovered importance of miRNAs in disease pathogenesis highlights their value as potential diagnostic and therapeutic targets.
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Cardiomiopatias/genética , Redes Reguladoras de Genes , MicroRNAs/genética , Isquemia Miocárdica/genética , Transcriptoma , Estudos de Casos e Controles , Humanos , MicroRNAs/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Via de Sinalização WntRESUMO
Upland cotton (Gossypium hirsutum L.) is an important cash crop that provides renewable natural fiber worldwide. Currently limited genetic base leads to a decrease in upland cotton genetic diversity. Multi-parent advance generation inter-cross (MAGIC) populations can be used to evaluate complex agronomic traits in crops. In this study, we developed an upland cotton MAGIC population. A total of 258 MAGIC population lines and their twelve founder lines were analyzed, using 432 pairs of simple sequence repeat (SSR) markers. Gene diversity indices and the polymorphism information content were calculated using polymorphism analyses. Our genotype analysis showed that 258 inbred lines could be divided into 158 genotypes. Among these, we identified 17 pairs of specific SSR primers on the A chromosome subgroups and 24 pairs of specific SSR primers on the B chromosome subgroups of upland cotton. These were related to 77 and 128 genotypes, respectively. Our results suggest that the upland cotton MAGIC population contained abundant genetic diversity and may provide enormous resources for future genetic breeding.
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Gossypium/genética , Polimorfismo Genético , Locos de Características Quantitativas , China , Cromossomos de Plantas/genética , Fibra de Algodão , Genótipo , Melhoramento VegetalRESUMO
Brain damage caused by perinatal asphyxia is dangerous for neonatal infants, but the mechanism by which it occurs remains elusive. In this study, microRNA-152 (miR-152) expression was induced by low oxygen levels in rat models of hypoxia brain damage, as well as in human brain microvascular endothelial cells (HBMECs) cultured in vitro. Analysis of the sequence of miR-152 revealed that the phosphatase and tensin homolog gene (PTEN) is probably the target of miR-152 both in humans and rats. When HBMECs were transfected with miR-152 mimics, PTEN expression was inhibited at both the mRNA and protein levels. Moreover, transfection with the miR-152 mimic also inhibited apoptosis induced by hypoxia. Furthermore, expression of the pro-apoptotic gene Bax was downregulated while the anti-apoptotic gene Bcl2 was upregulated after miR-152 mimic transfection. Taken together, these results indicate that miR-152 induced by hypoxia suppresses cell apoptosis and acts as a protective factor during hypoxia by repressing PTEN.
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Células Endoteliais/enzimologia , Hipóxia Encefálica/metabolismo , MicroRNAs/biossíntese , Oxigênio/metabolismo , PTEN Fosfo-Hidrolase/genética , Animais , Apoptose/genética , Encéfalo/irrigação sanguínea , Hipóxia Celular/fisiologia , Células Endoteliais/metabolismo , Células HEK293 , Humanos , Hipóxia Encefálica/patologia , Masculino , Microvasos/enzimologia , Microvasos/metabolismo , Modelos Animais , PTEN Fosfo-Hidrolase/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To establish macrophage iron overload model in vitro by co-culture macrophages with iron, and to explore the effect of iron overload on cell reactive oxygen species (ROS) and the impact of ROS on macrophages. METHOD: Iron overload group were treated with different concentrations (0, 5, 10, 20, 40, 80 µmol/L respectively) of ferric ammonium citrate (FAC). The control group was the group of macrophages without FAC treatment. We detected the number and state of cells, metabolic activity, the change of phagocytosis, the levels of ROS and reactive nitrogen, and changes of related oxidative stress signaling pathways in different groups. Changes in the above indexes were detected after application of deferasirox (DFX) to remove iron and the antioxidant N -acetylcysteine (NAC) to clear excess oxidative stress. RESULTS: (1)The levels of labile iron pool (LIP) in macrophages co-cultivated with iron was increased with the increase of iron concentration in a dose-dependent manner. The LIP levels was the highest in the macrophages treated with 80 µmol/L. (2)The increase of FAC concentration, the metabolic activity of macrophages in the 5 FAC-treated groups decreased to 51.58%, 40.98%, 16.23%, 3.46%, and 0.05% of the activity level of the control group (all P< 0.05). The group with the metabolic activity decreased to 16.23% (20 µmol/L) was selected as the iron overload group for the following experiments. (3)Compared with the control group, the number of macrophages in the iron overload group reduced to 32.80% (P<0.05), and the state of cells changed from adherence to partial suspension. The phagocytosis of macrophages in the iron overload group reduced to 20.40% of the control group (P<0.05). (4)Our further experiment showed that the levels of ROS and the activity nitrogen in the iron overload group increased by 7.71-and 1.45-fold compared with the control group (both P<0.05). The RT-PCR showed up-regulated mRNA expression of genes related with ROS production, i. e. nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX 4) gene related with ROS production and inducible nitric oxide synthase (iNOS) gene related with reactive nitrogen production, down-regulated mRNA expression of glutathione peroxidase 1 (GPX1) gene which participated in ROS clearance. Moreover, mRNA expression of phosphatidylinositol-3-kinase (PI3K) gene involved in oxidative stress signaling pathway in the iron overload group was up-regulated, while fork head protein O3 (FOXO3) which regulated oxidative stress through negative feedback showed a down-regulation level of mRNA expression compared with the control group. (5)After iron chelation and antioxidant treatment, the above-mentioned damage in the iron overload group were partially reversed. CONCLUSIONS: The damages of iron overload on macrophages may be mediated by inducing oxidative stress and activating oxidative stress signaling pathways. Our established model provides a method to explore the mechanism of iron overload on macrophage, and may shed some new light on possible therapeutic target in treating iron overload patients.
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Sobrecarga de Ferro , Macrófagos , Estresse Oxidativo , Acetilcisteína , Antioxidantes , Regulação para Baixo , Compostos Férricos , Humanos , Ferro , Fosfatidilinositol 3-Quinases , Compostos de Amônio Quaternário , Espécies Reativas de Oxigênio , Transdução de SinaisRESUMO
Metabolic syndrome (MS), a series of physiological and metabolic disorders caused by insulin resistance, combines clinical syndrome of abdominal obesity, diabetes or impaired glucose regulation, dyslipidemia, hypertension and other metabolic diseases. Several studies have found that multiple single nucleotide polymorphism (SNP) exists in adiponectin gene (ADIPOQ) and some unusual mutations might be related to hypoadiponectinemia and MS. This study aims to explore the relationship between ADIPOQ gene polymorphism and lipid levels and diabetes. A total of 1,049 confirmed MS cases were selected for research. From the perspective of potential functional SNPs of ADIPOQ gene, tag SNPs, combined with environmental factors, we studied the relationship between ADIPOQ gene polymorphism and phenotype (serum adiponectin level) and further analyzed the correlation of ADIPOQ gene polymorphism and metabolic syndrome components so as to clear the relationship between ADIPOQ gene polymorphism and lipid levels and diabetes and at the same time provide a scientific basis for preventing primarily MS etiology and screening high-risk groups.
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Adiponectina/genética , Diabetes Mellitus Tipo 2/genética , Síndrome Metabólica/genética , Polimorfismo de Nucleotídeo Único , Adiponectina/sangue , Adulto , Idoso , Povo Asiático/genética , Pressão Sanguínea/genética , Estudos de Casos e Controles , HDL-Colesterol/sangue , HDL-Colesterol/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/genética , Triglicerídeos/sangue , Triglicerídeos/genéticaRESUMO
We investigated the mechanism of the effect of lentinan on 3T3-L1 fat cell formation by inhibiting the peroxisome proliferator-activated receptor gamma (PPARγ)/protein kinase B (AKT) signaling pathway. 3T3-L1 fat cells were treated with 80 mM lentinan with or without the PPARγ activator, 100 mM rosiglitazone for 24 h. Reverse transcription-polymerase chain reaction was applied to detect PPARγ and AKT mRNA expression levels. Western blotting was used to detect AKT protein expression level. Compared with the control group, 80 mM lentinan increased PPARγ mRNA expression and downregulated AKT mRNA expression. After treatment with rosiglitazone, PPARγ mRNA expression increased by 78% (P < 0.05), while AKT mRNA expression decreased by 71% (P < 0.05). Lentinan treatment decreased AKT protein expression by 33%, and AKT protein expression in the lentinan and rosiglitazone co-treatment group was reduced by 28% compared with the lentinan treatment group. We found that 80 mM lentinan increased PPARγ mRNA expression and reduced AKT mRNA. Combination treatment with rosiglitazone increased this effect. This suggests that lentinan can depress 3T3-L1 fat cell formation by inhibiting the PPARγ/AKT signaling pathway.
Assuntos
Adipócitos/citologia , Lentinano/farmacologia , PPAR gama/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , PPAR gama/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rosiglitazona , Transdução de Sinais/genética , Tiazolidinedionas/farmacologiaAssuntos
Codificação Clínica/métodos , Bases de Dados Factuais/estatística & dados numéricos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Pioderma Gangrenoso/diagnóstico , Adulto , Idoso , Métodos Epidemiológicos , Feminino , Humanos , Classificação Internacional de Doenças , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Pioderma Gangrenoso/epidemiologia , Estudos RetrospectivosRESUMO
BACKGROUND: This study explored the prevalence of disturbed sleep and investigated its distribution characteristics and associated factors in adolescents in South China. METHODS: Junior middle school and senior high school students (n = 1221) were recruited from schools in Shanghai, China. Students completed a questionnaire using the Pittsburgh Sleep Quality Index and factors associated with disturbed sleep. RESULTS: The prevalence of a tendency towards poor sleep was 34.32% [95% confidence interval (CI): 31.66-36.98] with no significant difference between genders. This tendency increased with age, yielding a significant group effect (P < 0.01). In middle school and high school, the propensity towards poor sleep was 31.34% (95% CI: 28.29-34.39) and 42.22% (95% CI: 36.92-47.52) respectively. The factors associated with poor sleep were more television viewing during weekdays [odds ratio (OR): 1.56, CI: 1.36-1.71], more frequent computer/Internet use (OR: 1.25, CI: 1.08-1.39), earlier school starting time (OR: 1.12, CI: 1.07-1.28), and more time on homework during weekdays (OR: 1.78, CI: 1.51-1.98) and weekends (OR: 1.35, CI: 1.21-1.52) CONCLUSIONS: A tendency towards poor sleep is common in adolescents in South China and its incidence increases with age. The factors associated with this phenomenon indicate that poor sleep in adolescents could be improved, at least partly, by reducing the use of visual technologies and by changing school timetables.
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Transtornos do Sono-Vigília/epidemiologia , Adolescente , Fatores Etários , Criança , China/epidemiologia , Escolaridade , Feminino , Humanos , Masculino , Prevalência , Psicometria , Fatores de Risco , Instituições Acadêmicas , Sono/fisiologia , Transtornos do Sono-Vigília/etiologia , Fatores SocioeconômicosRESUMO
The influences of Ce, Sm and Yb on cavitation erosion of NAB alloy in 3.5% NaCl solution are evaluated using mass loss, SEM, 3D morphology and Tafel plot, respectively. The results show that the addition of Ce or Sm or Yb enhances the mechanical property of NAB alloy, and the sizes of κâ and κâ ¡ phases within NAB alloy decrease with adding Ce or Sm or Yb, resulting in the prevention of the propagation of the cracks caused by cavitation erosion initially originated at the phase boundaries between α and κ phases, and finally the cavitation erosion damage significantly decreases with adding Ce or Sm or Yb. The corrosion of NAB alloy in 3.5% NaCl solution can promote the cavitation erosion of NAB alloy, while the corrosion resistance of NAB alloy increases with the addition of Ce or Sm or Yb, and then the cavitation erosion resistance is accordingly improved with the addition of rare earth element.
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Two kinds of Ti-alloys, i.e., TiMo and TiNb alloys are manufactured in this paper, and their ultrasonic cavitation erosion behaviors in 0.1 M H2SO4 solution are evaluated by the mean depth erosion (MDE), SEM and white light photograph. The results show that MDE of TiMo and TiNb alloys obviously increase with increasing the cavitation erosion time, however, they evidently decrease with the increment of Mo or Nb content at each fixed cavitation erosion time, and even some large blank areas (uneroded areas) still exist on the sample surface after ultrasonic cavitation erosion for 2 h in the case of Ti10Mo and Ti20Nb samples, implying the enhanced anti-cavitation erosion property of Ti-alloy by adding Mo or Nb element. The MDE of Ti10Mo or Ti20Nb sample is lower than that of TC4 sample in the case of each cavitation erosion time, indicating the better cavitation erosion resistance of of Ti10Mo or Ti20Nb sample. The influences of Mo and Nb on the passivity of TiMo and TiNb alloys during the ultrasonic cavitation erosion are detected by potentiodynamic curves. The results display that Ti, TC4, TixMo (x = 1, 5, 10) and TixNb (x = 5, 10, 20) samples are all almost in the passive state within the potential region from 0VSCE to 1.5VSCE during ultrasonic cavitation erosion, and the passive current density evidently decreases with increasing Mo or Nb content, indicating the enhanced passive characteristic by adding Mo or Nb alloys during the ultrasonic cavitation erosion.
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Adaptation to stress requires coordinated interactions between the vascular and endocrine systems. Previously we demonstrated that restraint stress induces the expression of the major heat shock protein, HSP70, in the adrenal cortex of the rat. Here we demonstrate that restraint also induces expression of HSP70 in the vasculature. We further demonstrate that the adrenal and vascular responses are differentially regulated: the adrenal response is adrenocorticotropin dependent, whereas the vascular response is under adrenergic control. In addition, the adrenal response is restricted to members of the HSP70 gene family, whereas in vascular tissue the low molecular weight HSP, HSP27, is also induced by restraint. Further characterization of the vascular response revealed that HSP70 induction occurred in both the thoracic and abdominal aortas as well as in the vena cava. However, no HSP70 induction was apparent in the heart or in a wide variety of other tissues examined. In situ hybridization showed that the vascular expression was localized to the aortic smooth muscle cells with minimal expression in the endothelium. Induction of HSP70 mRNA in both the adrenal cortex and aorta was followed by an elevation in HSP70 protein. Maximum HSP70 protein levels were seen within 3-12 h after restraint, but declined thereafter. Stress induced HSP70 expression was dramatically reduced with age, which may explain, in part, the diminished tolerance to stress seen in elderly individuals.
Assuntos
Córtex Suprarrenal/fisiologia , Envelhecimento/metabolismo , Vasos Sanguíneos/metabolismo , Proteínas de Choque Térmico/biossíntese , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Estresse Fisiológico/metabolismo , Sistema Nervoso Simpático/fisiologia , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Sequência de Bases , Proteínas de Choque Térmico/genética , Masculino , Dados de Sequência Molecular , Ratos , Ratos Endogâmicos F344 , Ratos Wistar , Restrição FísicaRESUMO
PA-824 is a novel bicyclic nitroimidazole anti-tuberculosis (TB) drug. Cordyceps sinensis (Berk.) Sacc. (CS) was proven to be a good immunomodulatory compound. This research aimed to investigate the effect of CS on PA-824 in Mycobacterium tuberculosis (M.tb) infected mice (female CBA/J mice, 6 to 8 weeks of age and 20±2 g of weight). Mice were randomly assigned to 4 groups: PA-824, CS, PA-824+CS, and control. To verify the effect of PA-824 and CS on M.tb, after drug administration, mice lungs were harvested and bacterial colony formations were measured. Cells were isolated from infected lungs and spleens to analyze the percentage of CD4+ T cells (CD11a positive). Lung cells were cultured to detect the secretion of interferon-γ (IFN-γ) and interleukin-10 (IL-10) by ELISA. IFN-γ and IL-10 double-positive CD4+ cells in peripheral blood were measured by flow cytometry. The expression levels of IL-2 and IL-10 in mice lungs were analyzed by real-time PCR and western blot. Results showed that PA-824 combined with CS led to the lowest lung colony-forming units (CFU) counts among treated groups. Furthermore, this beneficial outcome might be associated with the decreased CD11a on CD4+ cells in mice lungs and spleens. Moreover, the suppressed secretion of IFN-γ and IL-10, and IL-10 expressions, as well as the decreased IFN-γ and IL-10 double-positive CD4+ cells in blood, could also be associated with the positive effect. However, no significant effect on IL-2 production was found. The combination of PA-824 and CS had more effective bacteriostatic and immunomodulatory effects on M.tb infected mice than PA-824 alone. In conclusion, CS has the potential to be an effective adjuvant in TB treatment.
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Antibacterianos/farmacologia , Cordyceps/química , Interleucina-10/imunologia , Mycobacterium tuberculosis/imunologia , Nitroimidazóis/farmacologia , Tuberculose Pulmonar/imunologia , Animais , Western Blotting , Modelos Animais de Doenças , Citometria de Fluxo , Imunomodulação/efeitos dos fármacos , Imunomodulação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos CBA , Mycobacterium tuberculosis/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The influence of Mo on ultrasonic cavitation erosion of 316 L stainless steel in 3.5% NaCl solution were investigated using an ultrasonic cavitation erosion (CE) facility. The morphologies of specimen after cavitation erosion were observed by scanning electron microscopy (SEM). The results showed that the addition of Mo can sharply decrease the mean depth of erosion (MDE) of 316 L SS, implying the increased resistance of cavitation erosion. In order to better understanding the influence of Mo on the cavitation erosion of 316 L SS, the semi-conductive property of passive films on 316 L SS containing different concentrations of Mo were studied by Mott-Schottky plot. Based on Mott-Schottky results and semiconductor physics, a physical model was proposed to explain the effect mechanism of Mo on cavitation erosion of 316 L SS.
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The influences of micro-particles on ultrasonic cavitation erosion of Ti6Al4V alloy in 0.1M H2SO4 solution were investigated using mass loss weight, scanning electron microscopy (SEM) and white light interferometer. Mass loss results revealed that the cavitation erosion damage obviously decreased with increasing particle size and mass concentration. Open circuit potential recorded during cavitation erosion shifted to positive direction with the decreased mass loss. Meanwhile, the mass loss sharply decreased with applying a positive potential during the entire ultrasonic cavitation erosion, and the relationship between the open circuit potential and the cavitation erosion resistance was discussed.
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The influence of the applied passive potential on the electronic property of the passive film formed on Ti at different potentials in 0.1M HCl solution during ultrasonic cavitation, was investigated by electrochemical impedance spectra (EIS) and Mott-Schottky plot. The influence of the applied passive potential on the structure and composition of the passive film was studied by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). The results showed that the applied passive potential can obviously affect the electronic property of the passive film formed on Ti during ultrasonic cavitation. The resistance of the passive film increased, and the donor density of the passive film decreased with increasing the potential. The flat band potential moved to positive direction and the band gap of the passive film moved to negative direction with increasing potential. AES and XPS results indicated that the thickness of the passive film increased evidently with applying passive potential. The passive film was mainly composed of the mixture of TiO and TiO2. While the TiO2 content increased with increasing the applied passive potential, and the crystallization of the passive film increased with the increased potential.