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1.
Sci Rep ; 14(1): 13135, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849526

ABSTRACT

In order to investigate the acoustic oscillation characteristics of gas-liquid pintle rocket engines and elucidate the path by which spray combustion process provides energy to the combustor pressure oscillation, a LOX/GCH4 pintle engine with rectangular combustor was designed. By adding transverse velocity disturbance for the first time, the acoustic response of spray combustion process was simulated, and the effect of excitation amplitude on acoustic response was researched. Numerical results show that the adopted transverse velocity disturbance can excite the first-order transverse acoustic oscillation with same excitation frequency in the engine combustor. The acoustic response maintenance mechanism under extrinsic excitation is summarized for pintle engines. Besides, the temperature distribution inside the engine combustor tends to be uniform, and the low-frequency oscillation caused by the flame transverse swing gradually disappears. The amplitude of combustor pressure oscillation is dominated by excitement amplitude and phase difference between the pressure and heat release in combustion reaction region. In addition, the time-averaged combustor pressure can be amplified mainly by transverse velocity disturbance. The research work can provide a reference for related fire tests on the acoustic response of a subscale gas-liquid pintle engine.

2.
Neuroreport ; 35(6): 399-405, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38526973

ABSTRACT

In tonal languages, tone perception involves the processing of both acoustic and phonological information conveyed by tonal signals. In Mandarin, in addition to four canonical full tones, there exists a group of weak syllables known as neutral tones. This study aims to investigate the impact of lexical frequency effects and prosodic information associated with neutral tones on the auditory representation of Mandarin compounds. We initially selected disyllabic compounds as targets, manipulating their lexical frequencies and prosodic structures. Subsequently, these target compounds were embedded into selected sentences and auditorily presented to native speakers. During the experiments, participants engaged in lexical decision tasks while their event-related potentials were recorded. The results showed that the auditory lexical representation of disyllabic compounds was modulated by lexical frequency effects. Rare compounds and compounds with rare first constituents elicited larger N400 effects compared to frequent compounds. Furthermore, neutral tones were found to play a role in the processing, resulting in larger N400 effects. Our findings showed significantly increased amplitudes of the N400 component, suggesting that the processing of rare compounds and compounds with neutral tones may require more cognitive resources. Additionally, we observed an interaction effect between lexical frequency and neutral tones, indicating that they could serve as determining cues in the auditory processing of disyllabic compounds.


Subject(s)
Electroencephalography , Speech Perception , Humans , Male , Female , Evoked Potentials , Language , Auditory Perception , Pitch Perception
3.
J Ovarian Res ; 13(1): 112, 2020 Sep 19.
Article in English | MEDLINE | ID: mdl-32950050

ABSTRACT

BACKGROUND: In this study we aimed to identify a prognostic signature in BRCA1/2 mutations to predict disease progression and the efficiency of chemotherapy ovarian cancer (OV), the second most common cause of death from gynecologic cancer in women worldwide. METHODS: Univariate Cox proportional-hazards and multivariate Cox regression analyses were used to identifying prognostic factors from data obtained from The Cancer Genome Atlas (TCGA) database. The area under the curve of the receiver operating characteristic curve was assessed, and the sensitivity and specificity of the prediction model were determined. RESULTS: A signature consisting of two long noncoding RNAs(lncRNAs), Z98885.2 and AC011601.1, was selected as the basis for classifying patients into high and low-risk groups (median survival: 7.2 years vs. 2.3 years). The three-year overall survival (OS) rates for the high- and low-risk group were approximately 38 and 100%, respectively. Chemotherapy treatment survival rates indicated that the high-risk group had significantly lower OS rates with adjuvant chemotherapy than the low-risk group. The one-, three-, and five-year OS were 100, 40, and 15% respectively in the high-risk group. The survival rate of the high-risk group declined rapidly after 2 years of OV chemotherapy treatment. Multivariate Cox regression associated with other traditional clinical factors showed that the 2-lncRNA model could be used as an independent OV prognostic factor. Analyses of data from the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) indicated that these signatures are pivotal to cancer development. CONCLUSION: In conclusion, Z98885.2 and AC011601.1 comprise a novel prognostic signature for OV patients with BRCA1/2 mutations, and can be used to predict prognosis and the efficiency of chemotherapy.


Subject(s)
Genes, BRCA1/physiology , Ovarian Neoplasms/genetics , RNA, Long Noncoding/genetics , Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Ovarian Neoplasms/pathology , Prognosis
4.
Int Immunopharmacol ; 85: 106512, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32454418

ABSTRACT

Clonorchis sinensis could induce inflammation, epithelial hyperplasia and fibrosis in the intrahepatic bile duct as a food-borne parasite, which was associated with the development of cholangiocarcinoma (CCA). Praziquantel was the most effective drug on treatment of this kind of parasite. However, new drugs with minimal toxicity to the host were urgently needed due to the side effects of Praziquantel and its CCA risk. In this study, helminth mitochondria respiratory chain blocker Wortmannilatone F (WF) and IL-8 analogue CXCL8 (3-72) K11R/G31P were used to treat BALB/C mice infected by Clonorchis sinensis. We investigated the gross and histopathological morphology of the liver, inflammation-associated cytokine IL-6, lipid peroxidation-related proteins cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX), collagen fiber accumulation and fibroblast-specific protein 1 (FSP1), malignant markers proliferating cell nuclear antigen (PCNA) and cytokeratin 19 (CK19), as well as the disinfection effect on these parasites in vitro. WF inhibited and killed the worms dramatically, and the combination of WF with G31P improved the condition of the hepatobiliary duct tissue greatly. These outcomes indicated that the combination of WF and G31P was a potential therapeutic method to treat the Clonorchis sinensis infection.


Subject(s)
Anthelmintics/therapeutic use , Clonorchiasis/drug therapy , Interleukin-8/therapeutic use , Macrolides/therapeutic use , Peptide Fragments/therapeutic use , Animals , Anthelmintics/pharmacology , Arachidonate 5-Lipoxygenase/metabolism , Clonorchiasis/metabolism , Clonorchiasis/parasitology , Clonorchiasis/pathology , Clonorchis sinensis/drug effects , Collagen/metabolism , Cyclooxygenase 2/metabolism , Interleukin-6/blood , Interleukin-8/pharmacology , Keratin-19/metabolism , Liver/drug effects , Liver/metabolism , Liver/pathology , Macrolides/pharmacology , Male , Mice, Inbred BALB C , Peptide Fragments/pharmacology , Proliferating Cell Nuclear Antigen/metabolism , S100 Calcium-Binding Protein A4/metabolism
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