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1.
Article in English | MEDLINE | ID: mdl-38616743

ABSTRACT

BACKGROUND: Limited chemotherapy efficacy and cancer stem cells (CSCs)-induced therapeutic resistance are major difficulties for tumour treatment. Adopting more efficient therapies to eliminate bulk-sensitive cancer cells and resistant CSCs is urgently needed. METHODS: Based on the potential and functional complementarity of gold and silver nanoparticles (AuNPs or AgNPs) on tumour treatment, bimetallic NPs (alloy) have been synthesized to obtain improved or even newly emerging bioactivity from a combination effect. This study reported a facile, green and economical preparation of Au-Ag alloy NPs using biocompatible polydopamine (PDA) as a reductant, capping, stabilizing and hydrophilic agent. RESULTS: These alloy NPs were quasi-spherical with rough surfaces and recorded in diameters of 80 nm. In addition, these alloy NPs showed good water dispersity, stability and photothermal effect. Compared with monometallic counterparts, these alloy NPs demonstrated a dramatically enhanced cytotoxic/pro-apoptotic/necrotic effect towards bulk-sensitive MCF-7 and MDA-MB-231 cells. The underlying mechanism regarding the apoptotic action was associated with a mitochondria-mediated pathway, as evidenced by Au3+/Ag+ mediated Mitochondria damage, ROS generation, DNA fragmentation and upregulation of certain apoptotic-related genes (Bax, P53 and Caspase 3). Attractively, these Au-Ag alloy NPs showed a remarkably improved inhibitory effect on the mammosphere formation capacity of MCF-7 CSCs. CONCLUSION: All the positive results were attributed to incorporated properties from Au, Ag and PDA, the combination effect of chemotherapy and photothermal therapy and the nano-scaled structure of Au-Ag alloy NPs. In addition, the high biocompatibility of Au-Ag alloy NPs supported them as a good candidate in cancer therapy.

2.
Front Vet Sci ; 11: 1347585, 2024.
Article in English | MEDLINE | ID: mdl-38371596

ABSTRACT

This study aims to investigate differences in metabolism regarding the transition cows. Eight cows were selected for the test. Serum was collected on antepartum days 14th (ap14) and 7th (ap7) and postpartum days 1st (pp1), 7th (pp7), and 14th (pp14) to detect biochemical parameters. The experiment screened out differential metabolites in the antepartum (ap) and postpartum (pp) periods and combined with metabolic pathway analysis to study the relationship and role between metabolites and metabolic abnormalities. Results: (1) The glucose (Glu) levels in ap7 were significantly higher than the other groups (p < 0.01). The insulin (Ins) levels of ap7 were significantly higher than pp7 (p = 0.028) and pp14 (p < 0.01), and pp1 was also significantly higher than pp14 (p = 0.016). The insulin resistance (HOMA-IR) levels of ap7 were significantly higher than ap14, pp7, and pp14 (p < 0.01). The cholestenone (CHO) levels of ap14 and pp14 were significantly higher than pp1 (p < 0.01). The CHO levels of pp14 were significantly higher than pp7 (p < 0.01). The high density lipoprotein cholesterol (DHDL) levels of pp1 were significantly lower than ap14 (p = 0.04), pp7 (p < 0.01), and pp14 (p < 0.01), and pp14 was also significantly higher than ap14 and ap7 (p < 0.01). (2) The interferon-gamma (IFN-γ) and tumor necrosis factor α (TNF-α) levels of ap7 were significantly higher than pp1 and pp7 (p < 0.01); the immunoglobulin A (IgA) levels of pp1 were significantly higher than ap7 and pp7 (p < 0.01); the interleukin-4 (IL-4) levels of pp7 were significantly higher than ap7 and pp1 (p < 0.01), the interleukin-6 (IL-6) levels of ap7 and pp1 were significantly higher than pp7 (p < 0.01). (3) Metabolomics identified differential metabolites mainly involved in metabolic pathways, such as tryptophan metabolism, alpha-linolenic acid metabolism, tyrosine metabolism, and lysine degradation. The main relevant metabolism was concentrated in lipid and lipid-like molecules, organic heterocyclic compounds, organic acids, and their derivatives. The results displayed the metabolic changes in the transition period, which laid a foundation for further exploring the mechanism of metabolic abnormalities in dairy cows in the transition period.

3.
Mol Pharm ; 21(3): 1450-1465, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38335466

ABSTRACT

The defeat of cancer is still a challenge due to the existence of cancer stem cells (CSCs) because they resist conventional chemotherapy via multifactor regulated mechanisms. Consequently, one-dimensional action toward CSCs cannot work. Herein, we used rationally designed hybrid nanoparticles as a combined cancer therapy, hoping to form a multidimensional control network. In this paper, gold/silver alloy nanoparticle decorated camptothecin nanocrystals were formulated according to complementary anti-CSC mechanisms from gold, silver, and organic drug. This smart drug formulation could combine chemotherapy and thermotherapy, target different tumor sites, and demonstrate versatile toxicity profiles from each component. Major results indicated that this nanosystem demonstrated indiscriminately effective cytotoxic/proapoptotic/necrotic activity against bulk MCF-7 cells and their CSC subpopulation, in particular under laser ablation. Moreover, this nanosystem displayed enhanced antineoplastic activity against CSC spheroids, resulting in a significant reduction in their number and size, that is, their self-renewal capacity. All the results indicated that CSCs upon treatment of these new hybrid nanoparticles underwent reduced stemness and conversion from the original quiescent state and recovered their sensitivity toward chemotherapy. The relevant anticancer mechanism was ascribed to NIR-pH dual responsive drug release, synergistic/combined thermo-chemotherapy of organic drug and inorganic alloy nanoparticles, enhanced cellular uptake mediated by alloy nanoparticles, and Ag+-induced biomembrane damage. This thermo-chemotherapy platform provides a new combinatorial strategy for inorganic and organic agents in the complete elimination of CSCs.


Subject(s)
Antineoplastic Agents , Nanoparticles , Neoplasms , Humans , Camptothecin/pharmacology , Silver , Gold/chemistry , Antineoplastic Agents/pharmacology , Nanoparticles/chemistry , Neoplastic Stem Cells , Alloys/pharmacology , Cell Line, Tumor , Neoplasms/pathology
4.
Sci Total Environ ; 905: 167324, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37748598

ABSTRACT

Understanding and managing mountain floods has become increasingly urgent, with global climate change and human activities exacerbating flood risk. However, flood research in Tianshan Mountains, a typical flood-prone mountainous region in China, is still insufficient. Here, we customized a set of flood research methods based on rainstorms and extreme snowmelt events, including a new flood counting method that comprehensively considered the frequency and magnitude of floods and the methods of flood classification and change attribution. We found that floods around the Chinese Tianshan Mountains (CTM) increased from 2014 to 2016 but decreased rapidly from 2016 to 2021, with storm floods, snowmelt floods, and mixed floods accounting for 38.3 %, 26.5 %, and 34.6 % of total flood events, respectively. The variation of floods was most significantly correlated with the average and extreme precipitation, followed by the temperature-driven average snowmelt change. Furthermore, atmospheric circulation anomalies and water vapor input from the western boundary of CTM caused decreasing precipitation and storm floods. Meanwhile, the warming hiatus also greatly impacted declining flood frequency. Notably, flood frequency is projected to rebound soon because of the rising precipitation and temperature, infrastructure aging, and reservoir abandonment, implying the present flood decline unsustainable. Our research develops a strategy to investigate short-term flood anomalies under climate oscillations around the CTM, providing insights into flood research and prevention in global mountainous regions.

5.
Materials (Basel) ; 16(13)2023 Jun 25.
Article in English | MEDLINE | ID: mdl-37444900

ABSTRACT

Polymer nanocomposites, which combine the advantages of polymers and fillers, are widely used in the field of automobile and aviation. Polyimine (PI) is an emerging thermoset material with remarkable properties, such as malleability, recyclability, and self-healing. Silicon carbide nano-whiskers (SiCw), as a cheap and high-hardness filler material, are chosen to enhance the properties of polyimine matrix. Silicon carbide nano-whisker-reinforced polyimine (PI-SiCw) nanocomposites were successfully fabricated by heat pressing, which was confirmed by FTIR and XPS tests. According to the results of mechanical tests, the mechanical properties of PI-SiCw nanocomposites were obviously improved. For example, with the addition of 0.5% SiCw, bending strength and bending elongation at break can be simultaneously increased by 33% and 148%, respectively. Surprisingly, the impact strength of PI-SiCw nanocomposites with 2% SiCw was increased by 154% compared to the matrix. SEM and EDS tests showed that the evenly distributed SiCw in the polyimine matrix enhanced the mechanical properties of PI-SiCw nanocomposites according to the mechanism of whiskers pulling out and the bridging principle. According to the TGA test results, the PI composites with SiCw retain a higher weight percentage at 800 °C. The reason was the combined effect of the good thermal stability of SiCw and their strong interactions with the PI matrix. As a result, introducing SiCw into the PI matrix imparts a slight improvement in thermal stability. This article presents an avenue of cost-effective research to enhance the mechanical properties of polyimine composites.

6.
Heliyon ; 9(6): e17143, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37360089

ABSTRACT

The equivalent pupil and the point spread function constitute the Fourier-Bessel transform relation. Based on this, we established the equivalent pupil function theory of rotating symmetric photon sieve and derived the Fourier transform of the flattened Gaussian function. The focal spot produced by this type of photon sieve exhibits a uniform intensity and phase distribution. According to the numerical results, the flattened Gaussian field distribution is consistent with the designed function. In addition, the nonuniformity in intensity and phase is approximately 1% and less than 1/170 wavelength, respectively.

7.
Front Surg ; 10: 1091062, 2023.
Article in English | MEDLINE | ID: mdl-37292489

ABSTRACT

Objective: To analyze the safety and efficacy of regular aspirin use after combined cerebral revascularization in patients with ischemic moyamoya disease. Methods: From December 2020 to October 2021, a total of 326 patients diagnosed with ischemic moyamoya disease by global cerebral angiography and undergoing first-time combined cerebral revascularization at the Moyamoya Disease Diagnosis and Treatment Research Center of our hospital were selected. Combined cerebral revascularization: superficial temporal artery-middle cerebral artery (STA-MCA) +encephalo-duro-myo-synangiosis (EDMS).Patients were screened by 2 senior physicians according to established inclusion/exclusion criteria. Patients were divided into aspirin and non-aspirin groups based on whether they received regular oral aspirin after surgery. A total of 133 patients were enrolled in the aspirin group. A total of 71 patients (204 cases) were enrolled in the non-aspirin group. Related data were collected before and 1 year after surgery and statistically analyzed to assess the prognosis of both groups. Results: In the two groups, the mRS Score was significantly different after one year (P = 0.023). TIA occurred in 26 patients (19.5%) in the aspirin group and 27 patients (38.0%) in the non-aspirin group within one year after surgery, and the difference between the two groups was statistically significant (P = 0.004). There was no significant difference in cerebral perfusion stage, the improvement rate of cerebral perfusion, Matsushima grading, bypass patency, and other complications within one year after the operation (P > 0.05). Conclusions: In patients with ischemic moyamoya disease who underwent combined cerebral revascularization, postoperative administration of aspirin can reduce the incidence of TIA without increasing the risk of bleeding, but it can not significantly improve the cerebral perfusion of the operation side, Matsushima grading, and bypass patency.

8.
Appl Opt ; 62(10): 2403-2409, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37132787

ABSTRACT

The photon sieve has had the problem of low diffraction efficiency since it was proposed. Dispersion from different waveguide modes in the pinholes also reduces the quality of focusing. To overcome the above drawbacks, we propose a kind of photon sieve working in the terahertz band. In a metal square-hole waveguide, the effective index is determined by the side length of the pinhole. We adjust the optical path difference by changing the effective indices of those pinholes. When the thickness of the photon sieve is fixed, the optical path in a zone is set to be a multilevel distribution from 0 to λ. In this way, the optical path differences caused by the waveguide effect of pinholes are used to compensate for those caused by the positions of pinholes. We also derive the focusing contribution of an individual square pinhole. The simulated example shows a 60 times increase in intensity than that of the equal-side-length single-mode waveguide photon sieve.

9.
Front Surg ; 10: 1074438, 2023.
Article in English | MEDLINE | ID: mdl-36860943

ABSTRACT

Objectives: We aimed to explore the results of OA-PICA-protected bypass grafting in patients with severe stenosis of the vertebral artery combined with PICA. Methods: Three patients with vertebral artery stenosis involving the posterior inferior cerebellar artery, treated by the Department of Neurosurgery of Henan Provincial People's Hospital from January 2018 to December 2021, were retrospectively analyzed. All the patients underwent Occipital Artery-Posterior Inferior Cerebellar Artery (OA-PICA) bypass surgery followed by elective vertebral artery stenting. Intraoperative indocyanine green fluorescence angiography (ICGA) showed patency of the bridge-vessel anastomosis. Postoperatively, the ANSYS software was used to assess the flow pressure changes and vascular shear in combination with the reviewed DSA angiogram. CTA or DSA was reviewed 1-2 years postoperatively, and the prognosis was evaluated by the modified Rankin Scale (mRS) one year postoperatively. Results: OA-PICA bypass surgery was completed in all patients, with intraoperative ICGA showing a patent bridge anastomosis, followed by stenting of the vertebral artery, and a review of the DSA angiogram. We also employed ANSYS software evaluation of the bypass vessel, which showed stable pressure and low turnover angle, suggesting a low rate of long-term occlusion of the vessel. All patients had no procedure-related complications during their hospitalization, and were followed up for a mean of 24 months postoperatively, with a good prognosis (mRS score of 1) at 1 year postoperatively. Conclusion: OA-PICA-protected bypass grafting is an effective treatment for patients with severe stenosis of the vertebral artery combined with PICA.

10.
RSC Adv ; 12(55): 35613-35615, 2022 Dec 12.
Article in English | MEDLINE | ID: mdl-36540400

ABSTRACT

[This corrects the article DOI: 10.1039/C9RA04026A.].

11.
Comput Intell Neurosci ; 2022: 7620287, 2022.
Article in English | MEDLINE | ID: mdl-36052043

ABSTRACT

Moyamoya disease is a medical condition that shows the typical characteristics like continuous and chronic thickening of the walls and the contraction of the internal carotid artery; as a result, the internal diameter of the artery gets narrowed. There are six phases of the disease ranging from I to VI (moyamoya vessels completely disappear, followed by the complete blockage of the arteries). Surgery is a commonly recommended treatment for the moyamoya disease. Our research study identifies the effect of autologous bone marrow stem cell therapy (ABMSCT) on the levels of inflammatory factors and Conexin43 (Cx43) protein in patients suffering from moyamoya. In our study, we have selected 52 moyamoya patients admitted to our hospital from 30 July 2019 to 10 February 2020. The control group (CG) was treated with superficial temporal artery to a middle cerebral artery (STA-MCA) bypass + encephalo-duro-myosinangiosis (EDMS). The experimental group (Exp. Grp) was treated with ABMSC. The cerebral vascular tissue of the patients was treated with hematoxylin-eosin (HE) staining. Immunohistochemical staining was used to identify the levels of Cx43 protein. The concentrations of vascular endothelial growth factor (VEGF), inflammatory factor interleukin-6 (IL6), interleukin-1ß (IL1ß), tumor necrosis factor (TNFα), and anti-inflammatory factor interleukin-1ß (IL1ß) were determined by enzyme-linked immunosorbent assay (ELISA). We have found that after treatment of the expression of Cx43 protein, the proportions of grade IV (7.7%), grade III (311.5%), and grade II (3.8%) patients in the Exp. Grp were lower than those in the CG. The proportion of grade I patients in the Exp. Grp (77%) was higher than that in the CG (38.5%). After treatment, the inflammatory factors IL6 (0.97 ± 0.82 pg/mL), IL1ß (8.33 ± 1.21 pg/mL), and TNFα (1.73 ± 0.71 pg/mL) in the Exp. Grp were lower than those in the CG. The anti-inflammatory factor IL1ß (15.09 ± 4.72 pg/mL) increased in the Exp. Grp compared with the CG (11.25 ± 3.48 pg/mL) post treatment. Intracranial infection, hydrocephalus, hemiplegia, and transient neurological dysfunction in the Exp. Grp were lower than those in the CG, with statistical differences (P < 0.05). Our study suggests that the treatment of autologous bone marrow stem cells (ABMSC) was beneficial to balance the inflammatory response of disorders, reduce the damage of vascular tissue in the brain, and regulate tissue repair by co-acting with various inflammatory factors as compared to traditional surgery. We conclude that the involvement of Cx43 in the occurrence and development of moyamoya. We also have found that the risk factors of intracranial infection after ABMSCT were less as compared to those after conventional surgery.


Subject(s)
Cerebral Revascularization , Moyamoya Disease , Bone Marrow/pathology , Bone Marrow/surgery , Bone Marrow Cells/pathology , Connexin 43 , Humans , Interleukin-1beta , Interleukin-6 , Moyamoya Disease/pathology , Moyamoya Disease/therapy , Tumor Necrosis Factor-alpha , Vascular Endothelial Growth Factor A
12.
Sensors (Basel) ; 22(15)2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35957436

ABSTRACT

Stiffened structure-induced gain-phase errors degrade the performance of the high-resolution two-dimensional multiple signal classification (2D-MUSIC) algorithm, which makes it impossible to ensure the high accuracy of impact localization results. To eliminate the localization bias caused by these errors, a calibrated 2D-MUSIC-based impact localization method is first introduced. Firstly, time-frequency characteristics of the non-stationary impact signals are evaluated by experiment to obtain a clear first wave packet or a wave packet that purely corresponds to a single mode through continuous wavelet transform (CWT). Then, the uniform linear array covariance matrix with gain-phase errors is calibrated to be constructed as a Toeplitz structural matrix. By reconstructing covariance matrix R, 2D-MUSIC-based impact localization is calibrated for stiffened curved composite structures. Experimental research on the stiffened curved composite panel is carried out, and these impact localization results demonstrate the validity and effectiveness of the calibrated 2D-MUSIC-based method.

13.
Biochem Biophys Res Commun ; 625: 38-45, 2022 10 15.
Article in English | MEDLINE | ID: mdl-35944362

ABSTRACT

Glioma is a clinically heterogeneous disease with a poor prognosis. Berberine (BBR), as a multi-target anti-tumor alkaloid, has the ability to penetrate the blood-brain barrier and shows cytotoxicity to glioma cells. In previous studies, we demonstrated that berberine inhibits glioma cell proliferation by inhibiting mutant p53 protein and promoting mitochondrial damage. In addition, berberine has been shown to reduce collagen accumulation in pulmonary fibrosis, diabetic nephropathy and arthritis. However, its effect on collagen in cancer needs to be further elucidated. In this study, we proved that the collagen XI alpha 1 chain (COL11A1) is highly expressed in glioma cell lines and associated with migration and invasion of glioma cells. Knocking down COL11A1 caused decreased expression of MMPs. Berberine could inhibit the migration and invasion of glioma cells by suppressing the TGF-ß1/COL11A1 pathway and changes actin cytoskeleton arrangement. Nude mouse subcutaneous xenografts model also showed that berberine inhibited the expression of COL11A1 in vivo. Collectively, berberine that targets COL11A1 to inhibit glioma migration and invasion, may serve as a promising candidate for the development of anti-glioma drugs in the future.


Subject(s)
Berberine , Glioma , Animals , Berberine/pharmacology , Cell Line, Tumor , Cell Movement , Cell Proliferation , Collagen/pharmacology , Collagen Type XI , Glioma/drug therapy , Glioma/pathology , Humans , Mice , Mice, Nude , Transforming Growth Factor beta1/metabolism
14.
Front Neurosci ; 16: 922482, 2022.
Article in English | MEDLINE | ID: mdl-35774553

ABSTRACT

Purpose: To investigate the characteristics of cerebral perfusion and hemodynamics of bypass grafting in the treatment of moyamoya disease (MMD) using the iFlow color-coded flow map in comparison with magnetic resonance imaging-perfusion-weighted imaging (MRI-PWI) and computational fluid dynamic (CFD) analysis. Materials and Methods: Patients with MMD treated with bypass grafting who had undergone MRI PWI and digital subtraction angiography for iFlow color-coded map was retrospectively enrolled and CFD was performed for calculating the hemodynamic stresses around the bypass grafting. Results: Forty-five patients with unilateral MMD treated with bypass surgery were enrolled. The bypass surgery was successful in all patients, with no severe neurological complications during the periprocedural period. Followed up for 4-12 months (median 5.5), the neurological function was good in all patients. The cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time to peak (TTP) were significantly (p < 0.05) improved in the middle cerebral artery distribution area on the surgical side before and after vascular bypass, and the difference of TTP (s) measured from the proximal bifurcation of common carotid artery to the confluence of sinus was also significant (p < 0.05). A significant (p < 0.05) positive correlation existed in the perfusion parameters between the iFlow blood perfusion and the MRI-PWI perfusion, with r-value for TTP of 0.765 (p < 0.01). The iFlow color-coded blood flow map showed warm color changes on the diseased side, similar to those on the contralateral side. In CFD analysis, the hemodynamic stresses were all improved, in and around the bypass grafting and distal vessels, which were beneficial to blood flow entering distal arterial branches. Conclusion: The iFlow color-coded flow map can be used to analyze cerebral perfusion after bypass grafting for MMD, similar to MRI-PWI, and CFD can be used to analyze the hemodynamics after bypass grafting, revealing improved hemodynamics to promote blood flow entering distal arteries.

15.
World J Clin Cases ; 10(14): 4617-4624, 2022 May 16.
Article in English | MEDLINE | ID: mdl-35663064

ABSTRACT

BACKGROUND: Moyamoya disease is essentially an ischemic cerebrovascular disease. Here, we describe a case of acute recurrent cerebral infarction caused by moyamoya disease with concurrent adenomyosis which, to our knowledge, is the first in the literature. A literature review is also presented. CASE SUMMARY: A 38-year-old female presented to the Research and Treatment Center of Moyamoya Disease in our hospital with "left limb weakness" as the main symptom. She was diagnosed with acute cerebral infarction and moyamoya disease through magnetic resonance imaging and digital subtraction angiography. Prior to this, she had experienced a prolonged menstrual period of one-month duration. This was investigated and adenomyosis was diagnosed. After passing the acute cerebral infarction phase, the patient underwent surgery for adenomyosis followed by combined cerebral revascularization. During the postoperative follow-up, improvements of the perfusion imaging stage and modified Rankin Scale were observed. A review of the literature showed only 16 reported cases of gynecological diseases complicated with stroke. The clinical characteristics, pathogenesis, therapeutic effects, and long-term prognosis of these cases have been studied and discussed. CONCLUSION: In patients with moyamoya disease, early management of gynecological-related bleeding disorders is essential to prevent the complications of cerebral events.

16.
Front Surg ; 9: 863718, 2022.
Article in English | MEDLINE | ID: mdl-35620191

ABSTRACT

Intracranial aneurysms are vascular diseases characterized by local aneurysms of intracranial arteries. Their etiology involves a variety of environmental and genetic factors. Unruptured intracranial aneurysms (UIAs) are more common in intracranial aneurysms, but once an aneurysm is ruptured, the fatality rate and disability rate are extremely high. Therefore, accurate assessment of each step in the detection of intracranial aneurysms, assessment of the risk of rupture, formulation of treatment strategies, and treatment benefits will help to better treat the disease. At present, the treatment of intracranial aneurysms is limited. Except for surgical intervention, there are no other effective methods. Therefore, when a patient has a UIA, the formulation of treatment and management strategies is a difficult issue facing neurosurgery. This article introduces the choice of different treatment strategies for 3 patients with intracranial aneurysms complicated with other diseases and reviews the literature.

17.
Sci Rep ; 12(1): 4533, 2022 Mar 16.
Article in English | MEDLINE | ID: mdl-35296706

ABSTRACT

The static method of isochoric saturation was used to measure the solubilities of CO2, O2 and N2 in rocket propellant 5 (RP5) at temperatures ranging from 253.15 to 323.15 K in 10 K intervals and pressures ranging from 0 to 120 kPa. The measurement accuracy of the constructed experimental setup was verified by measuring the solubility of CO2 in water. The relative expanded uncertainty (k = 2) in the solubility data was less than 4.0%. The solubilities of CO2, O2 and N2 in RP5 increased with pressure. As the temperature increased, the solubility decreased for CO2 solubility and increased for O2 and N2. Henry's constants for the three gases in RP5 decreased over the experimental temperature and pressure ranges in the order of N2 > O2 > CO2. The measured solubilities of CO2, O2 and N2 could be fitted with a modified Krichevsky-Kasarnovsky equation, and the maximum deviation between the measured and calculated data was less than 8.04%, 7.03% and 6.18%, respectively.

18.
J Neurol Surg A Cent Eur Neurosurg ; 83(6): 606-610, 2022 Nov.
Article in English | MEDLINE | ID: mdl-34030184

ABSTRACT

BACKGROUND: Intracranial aneurysms may be misdiagnosed with other vascular lesions such as vascular loops, infundibulum, or the stump of an occluded artery (very rare and reported compromising only the middle cerebral artery and the posterior circulation territory). Our aim was to describe a unique case of occlusion of an anterior cerebral artery mimicking a cerebral aneurysm in a probable moyamoya disease patient, and to highlight its clinical presentation, diagnosis, and management, and to perform an extensive literature review. CASE: A 67-year-old man suffering from recurrent dizziness for 3 months. Previous medical history was unremarkable. Brain magnetic resonance angiography (MRA) and digital subtraction angiography (DSA) demonstrated occlusion of the right middle cerebral artery (MCA) associated with a "probable moyamoya disease" and an aneurysm-like shadow protruding lesion at the anterior communicating artery (AcomA). Perfusion images showed ischemia along the right temporo-occipital lobe. Due to MCA occlusion with perfusion deficits and unspecific symptoms, we offered a right side encephalo-duro-myo-synangiosis (EDMS) and clipping of the AcomA aneurysm in one session. Intraoperatively, there was no evidence of the AcomA aneurysm; instead, this finding corresponded to the stump of the occluded right anterior cerebral artery (A1 segment). This segment appeared to be of yellowish color due to atherosclerosis and lacked blood flow. The patient underwent as previously planned a right side EDMS and the perioperative course was uneventful without the presence of additional ischemic attacks. CONCLUSION: Arterial branch occlusions can sometimes present atypical angiographic characteristics that can mimic a saccular intracranial aneurysm. It is relevant to consider this radiographic differential diagnosis, especially when aneurysm treatment is planned.


Subject(s)
Arterial Occlusive Diseases , Intracranial Aneurysm , Moyamoya Disease , Male , Humans , Aged , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Intracranial Aneurysm/complications , Anterior Cerebral Artery/diagnostic imaging , Anterior Cerebral Artery/surgery , Moyamoya Disease/surgery , Cerebral Angiography
19.
Materials (Basel) ; 14(22)2021 Nov 09.
Article in English | MEDLINE | ID: mdl-34832148

ABSTRACT

Piezoelectric sensors array based damage imaging method as a high resolution source localization algorithm is becoming a promising method in structural health monitoring (SHM) technology. However, the environmental variations could affect the gain-phase of array signal. This paper experimentally evaluates the environmental effects on piezoelectric sensors array, and presents a compensated 2D-MUSIC based damage imaging method for composite structures. Firstly, detailed analysis and comparison discussion about the gain-phase difference of array signal when the environmental parameters change, and the gain-phase changes respect to the environmental parameters could be obtained. Secondly, array error matrix is structured and substituted into the steering vector of the original 2D-MUSIC algorithm to compensate. Finally, the compensated 2D-MUSIC algorithm is applied for estimating the initial estimates of damage. After substituting these initial estimates, the cost function is minimized by adaptive iterative calculating the reasonable location of the damage source. The experiments on an epoxy laminate plate demonstrate the validity and effectiveness of the proposed method.

20.
Ying Yong Sheng Tai Xue Bao ; 31(2): 590-598, 2020 Feb.
Article in Chinese | MEDLINE | ID: mdl-32476353

ABSTRACT

The variations of runoff and sediment flux are important factors influencing the socioeconomic development of Thailand. Based on the dataset of runoff and sediment flux during 1980-2014 at the Ubon hydrological station in the lower Mun River, a tributary of the Mekong River, the temporal variations of runoff and sediment flux were analyzed with the linear regression method, Mann-Kendall test, and wavelet transform method. The driving forces for the variations of runoff and sediment flux were discussed. The results showed that annual runoff in the Mun River basin increased slightly, while the sediment flux presented a decreasing trend. The changes of sediment flux and runoff were consistent before 2000. However, the sediment flux significantly decreased after 2000. During the study period, both the runoff and sediment flux during the flood seasons showed decrease trend. The abrupt change points of runoff and sediment flux did not occur in the same year, which were in 1999, 2006 and 2011 for runoff and in 1986, 1999 and 2011 for sediment, respectively. The main cycles of runoff amount were 14, 8 and 4 years, respectively, while those of sediment flux were 32, 12, 9 and 4 years, respectively. Except for the 32-year cycle of sediment flux, the main cycles of runoff and sediment flux were almost similar and both were mainly related to the Southern Oscillation, polar movement, sunspot activity, and other factors. There was a significant correlation between monthly runoff and sediment flux. Sea-air interaction and human activity were important factors influencing runoff and sediment flux in the Mun River basin. El Nino and La Nina were closely related to rainfall which in turn affected the runoff and sediment flux in the basin. Since 2000, the construction area increased and the forest area decreased, which increased the runoff in the basin, while the reservoirs and other engineering measures reduced the runoff and sediment flux, and thus offset the impact of decreased forest lands on sediment flux.


Subject(s)
Environmental Monitoring , Rivers , Human Activities , Humans , Hydrology , Thailand
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