Publications by authors named "Wenhao Wu"

70 Publications

Role of molecular size of volatile organic compounds on their adsorption by KOH-activated micro-mesoporous carbon.

J Hazard Mater 2021 Sep 29;424(Pt B):127355. Epub 2021 Sep 29.

Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China; Zhejiang University-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311200, China. Electronic address:

KOH-activated carbon (KAC) with high surface area and abundant micropores are widely used in adsorbing volatile organic compounds (VOCs). Kinetic diameters (σ) of VOCs are an important factor controlling diffusion of VOCs into pores of adsorbent. Yet the influence of kinetic diameters of VOCs on their adsorption by KAC remains unclear. Here, we investigated the dynamic adsorption of VOCs with various kinetic diameters on a prepared KAC with high surface area of 3100 m/g, pore volume of 2.08 cm/g and average pore width (D) of 2.68 nm. Adsorption affinity was negatively correlated with size difference (D-σ), indicating that pore width of adsorbent should close to σ to obtain a strong interaction between VOCs and adsorbents. Amounts adsorbed were positively correlated with σ at low relative pressures (p/p < 0.01), and negatively correlated with σ at high relative pressures (p/p > 0.044). The above results suggest that larger molecules with higher affinities are preferentially adsorbed at low relative pressures, amounts adsorbed of smaller molecules are larger than that of bigger molecules at high relative pressures. This study provided new insights into adsorption mechanisms mediated by σ and the development of next generation adsorbents for efficient removal of VOCs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2021.127355DOI Listing
September 2021

Corrigendum: Complete Genome Sequences of Two Novel KPC-2-Producing IncU Multidrug-Resistant Plasmids From International High-Risk Clones of in China.

Front Microbiol 2021 26;12:756781. Epub 2021 Aug 26.

Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China.

[This corrects the article DOI: 10.3389/fmicb.2021.698478.].
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmicb.2021.756781DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8429828PMC
August 2021

Crucial Roles of microRNA-Mediated Autophagy in Urologic Malignancies.

Int J Biol Sci 2021 31;17(13):3356-3368. Epub 2021 Jul 31.

Department of Urology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, 318000, Zhejiang, China.

Urologic oncologies are major public health problems worldwide. Both microRNA and autophagy, separately or concurrently, are involved in a variety of the cellular and molecular processes of multiple cancers, including urologic malignancies. In this review, we have summarized the related studies and found that microRNA-mediated autophagy acted as carcinogenic factors or suppressors in prostate cancer, kidney cancer, and bladder cancer. MiRNAs, targeted genes, and the different signaling pathways constitute a complex network that orchestrates autophagy regulation, militating the oncogenic and tumor-suppressive effects in urologic malignancies. Aberrant expression of miRNAs may induce the dysregulation of the autophagy process, resulting in tumorigenesis, progression, and resistance to anticancer therapies. Targeting specific miRNAs for autophagy modulation may present as reliable diagnostic and prognostic biomarkers or promising therapeutic strategies for urologic oncologies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7150/ijbs.61175DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8416737PMC
July 2021

Emergence of a KPC Variant Conferring Resistance to Ceftazidime-Avibactam in a Widespread ST11 Carbapenem-Resistant Clone in China.

Front Microbiol 2021 16;12:724272. Epub 2021 Aug 16.

Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.

Carbapenem-resistant (CRKP) infection poses a great threat to public health worldwide, and KPC-2-producing strains are the main factors responsible for resistance to carbapenems in China. Ceftazidime/avibactam (CZA) is a novel β-lactam/β-lactamase inhibitor combination with good activity against KPC-2 carbapenemase and is becoming the most important option for treating KPC-producing CRKP infection. Here, we report the emergence of a novel KPC-2 variant, designated KPC-74, produced by strain KP55, that conferred CZA resistance in a patient after CZA exposure. The novel variant showed a deletion of 6 nucleotides at positions 712-717 compared with , and this deletion resulted in the consequent deletion of glycine and valine at positions 239 and 240. Antimicrobial susceptibility testing showed that KP55 presents multidrug resistance, including resistance to CZA and ertapenem, but is susceptible to imipenem, meropenem, and colistin. The gene was located on a plasmid, as determined by S1-nuclease pulsed-field gel electrophoresis followed by southern blotting, and confirmed to be 133,766 bp in length by whole-genome sequencing on both the Illumina and MinION platforms. The CZA resistance phenotype of the novel KPC variant was confirmed by both transformation of the -harboring plasmid and a gene cloning assay, showing a 64-fold higher CZA minimum inhibitory concentration (MIC) than the recipient strains. The G239_V240del observed in KPC-74 was outside the omega-loop region but was still close to the active site Ser70 and omega-loop in the protein tertiary structure. The enzyme kinetic parameters and IC values further indicated that the hydrolytic activity of the KPC-74 enzyme against ceftazidime was potentiated twofold and that the affinity between KPC-74 and avibactam was alleviated 17-fold compared with that of the KPC-2 allele. This CZA resistance mediated by KPC-74 could be selected after CZA therapy and evolved to be more diverse and heterogeneous. Surveillance of CZA resistance is urgently needed in clinical settings.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmicb.2021.724272DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8415713PMC
August 2021

Complete Genome Sequences of Two Novel KPC-2-Producing IncU Multidrug-Resistant Plasmids From International High-Risk Clones of in China.

Front Microbiol 2021 21;12:698478. Epub 2021 Jul 21.

Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China.

The rapidly increasing prevalence of carbapenemase 2 (KPC-2)-producing bacteria has become a serious challenge to public health. Currently, the gene is mainly disseminated through plasmids of different sizes and replicon types. However, the plasmids carrying the gene have not been fully characterized. In this study, we report the complete genome sequences of two novel -harboring incompatibility group U (IncU) plasmids, pEC2341-KPC and pEC2547-KPC, from international high-risk clones of isolated from Zhejiang, China. Two KPC-2-producing isolates (EC2341 and EC2547) were collected from clinical samples. Whole-genome sequencing (WGS) analysis indicated that EC2341 and EC2547 belonged to the ST410 and ST131 clones, respectively. S1-nuclease pulsed-field gel electrophoresis (S1-PFGE), Southern blot and conjugation experiments confirmed the presence of the gene on the pEC2341-KPC plasmid and that this was a conjugative plasmid, while the gene on the pEC2547-KPC plasmid was a non-conjugative plasmid. In addition, plasmid analysis further revealed that the two -harboring plasmids have a close evolutionary relationship. To the best of our knowledge, this is the first report of strains carrying the gene on IncU plasmids. The emergence of the IncU-type -positive plasmid highlights further dissemination of in . Therefore, effective measures should be taken immediately to prevent the spread of these positive plasmids.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmicb.2021.698478DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8335537PMC
July 2021

Skin Infection in a Previously Healthy Patient: A Case Study.

Infect Drug Resist 2021 28;14:2965-2968. Epub 2021 Jul 28.

Department of Infectious Diseases, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, 310014, People's Republic of China.

Nontuberculous mycobacteria infections present mostly pulmonary characteristics. However, the incidence of skin and soft tissue infections caused by nontuberculous mycobacteria has increased in part due to the increased popularity of cosmetic and plastic surgery. Here, we report a case of infection. The patient underwent a one-year course of anti-infection therapy. To the best of our knowledge, this is the first report of a previously healthy patient presenting a skin and soft tissue infection caused by . Clinical personnel should be aware of possible causes of persistent skin and soft tissue infection after cosmetic and plastic surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/IDR.S322717DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8326274PMC
July 2021

Sorption mechanism of naphthalene by diesel soot: Insight from displacement with phenanthrene/p-nitrophenol.

J Environ Sci (China) 2021 Aug 1;106:136-146. Epub 2021 Feb 1.

Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China. Electronic address:

The nonlinear sorption of hydrophobic organic contaminants (HOCs) could be changed to linear sorption by the suppression of coexisting solutes in natural system, resulting in the enhancement of mobility, bioavailability and risks of HOCs in the environment. In previous study, inspired from the competitive adsorption on activated carbon (AC), the displaceable fraction of HOCs sorption to soot by competitor was attributed to the adsorption on elemental carbon fraction of soot (EC-Soot), while the linear and nondisplaceable fraction was attributed to the partition in authigenic organic matter of soot (OM-Soot). In this study, however, we observed that the linear and nondisplaceable fraction of HOC (naphthalene) to a diesel soot (D-Soot) by competitor (phenanthrene or p-nitrophenol) should be attributed to not only the linear partition in OM-Soot, but also the residual linear adsorption on EC-Soot. We also observed that the competition on the surface of soot dominated by external surface was different from that of AC dominated by micropore surface, i.e., complete displacement of HOCs by p-nitrophenol could occur for the micropore surface of AC, but not for the external surface of soot. These observations were obtained through the separation of EC-Soot and OM-Soot from D-Soot with organic-solvent extraction and the sorption comparisons of D-Soot with an AC (ACF300) and a multiwalled carbon nanotube (MWCNT30). The obtained results would give new insights to the sorption mechanisms of HOCs by soot and help to assess their environmental risks.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jes.2021.01.017DOI Listing
August 2021

Synthesis and biological evaluation of novel ligustrazine-chalcone derivatives as potential anti-triple negative breast cancer agents.

Bioorg Med Chem Lett 2021 Sep 27;47:128230. Epub 2021 Jun 27.

The Fifth Affiliated Hospital & School of Pharmaceutical Sciences, Key Laboratory of Molecular Target & Clinical Pharmacology, Guangzhou Medical University, Guangzhou 511436, China; The State Key Laboratory of Respiratory Disease & NMPA Key Laboratory for Clinical Research and Evaluation of Drug for Thoracic Diseases, Guangzhou Medical University, Guangzhou 511436, China. Electronic address:

A series of novel ligustrazine-chalcone hybrids were synthesized and evaluated for their in vitro and in vivo antitumor activities. The results showed that most of these compounds exhibited significant in vitro cytotoxicity against MDA-MB-231, MCF-7, A549 and HepG2 cell lines with IC values as low as sub-micromole. Among them, compounds 6c and 6f possessed better comprehensive characteristics for the antiproliferation effects on both MDA-MB-231 (IC: 6c, 1.60 ± 0.21 μM; 6f, 1.67 ± 1.25 μM) and MCF-7 (IC: 6c, 1.41 ± 0.23 μM; 6f, 1.54 ± 0.30 μM). They also exhibited the potent colony-formation inhibitory abilities on above two cell lines in both concentration and time dependent manners, as well as the significantly suppression capabilities against the migration of such cell lines in a concentration dependent manner by wound-healing assay. Of note, compound 6c could significantly induce the apoptosis of MDA-MB-231 cells in a concentration dependent manner and inhibited the transformation of the growth cycle of MDA-MB-231 cells and blocked the cell growth cycle in G0/G1 phase. Moreover, the in vivo antiproliferation assay of compound 6c on TNBC model indicated such compound had a remarkable potency against tumor growth with a widely safety window. Further immunohistochemistry analysis illustrated that compound 6c was provided with a potent capacity to significantly reduce the Ki-67 positive rate in a dose dependent manner. All the results suggested that these hybrids presented both in vitro and in vivo proliferation inhibition potency against breast cancer and further development with good therapeutic potential should be of great interest.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bmcl.2021.128230DOI Listing
September 2021

NO Gas Sensing Performance of a VO(B) Ultrathin Vertical Nanosheet Array: Experimental and DFT Investigation.

ACS Appl Mater Interfaces 2021 Jul 28;13(27):31968-31977. Epub 2021 Jun 28.

School of Microelectronics, Tianjin University, Tianjin 300072, P. R. China.

A VO(B) ultrathin vertical nanosheet array was prepared by the hydrothermal method. The influence of the concentration of oxalic acid on the crystal structure and room-temperature NO sensing performance was studied. The morphology and crystal structure of the nanosheets were characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. Room-temperature gas sensing measurements of this structure to NO with a concentration span from 0.5 to 5 ppm were carried out. The experimental results showed that the thickness of the vertical VO(B) nanosheet was lower than 20 nm and close to the 2 times Debye length of VO(B). The response of the sensor based on this structure to 5 ppm NO was up to 2.03, and the detection limit was 20 ppb. Its high response performance was due to the fact that the target gas could completely control the entire conductive path by forming depletion layers on the surface of VO(B) nanosheets. Density functional theory was used to analyze the adsorption of NO on the VO(B) surface. It is found that the band gap of VO(B) becomes narrower and the Fermi level moves to the valence band after NO adsorption, and the density of states near the Fermi level increases significantly. This ultrathin vertical nanosheet array structure can make VO(B) detect NO with high sensitivity at room temperature and therefore has potential applications in the field of low-power-consumption gas sensors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.1c05251DOI Listing
July 2021

Clinical Features and Surgical Results of Pediatric Pleomorphic Xanthoastrocytoma: Analysis of 17 Cases with a Literature Review.

World Neurosurg 2021 07 6;151:e778-e785. Epub 2021 May 6.

Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, PR China. Electronic address:

Background: Pediatric pleomorphic xanthoastrocytoma (PXA) is a rare brain tumor. To date, there are few studies dedicated to this kind of pediatric tumor. The aim of this study was to investigate the clinicopathologic characteristics of pediatric PXA.

Methods: We retrospectively analyzed 17 pediatric patients diagnosed with PXA histologically between July 2009 and December 2018. We also reviewed the relevant literature.

Results: The majority of pediatric PXAs had cystic components and peritumoral edema, and approximately 40% of the tumors had calcifications. All large tumors (≥5 cm) were located in the nontemporal lobes except 1 (P = 0.05). Furthermore, the large tumors were primarily solid-cystic or cystic with mural nodules radiologically, while tumors measuring <5 cm were mainly solid or solid with cystic changes (P = 0.02). All patients underwent surgery, and 15 patients experienced complete tumor removal. Histologically, 11 patients had grade II PXAs and 6 patients had grade III PXAs. After the operation, most of the patients recovered uneventfully and the seizures were well controlled. The mean follow-up time was 43 months. Five patients received radiotherapy or chemotherapy. One patient had tumor recurrence 5 years after the first operation and underwent repeat surgery.

Conclusions: Cystic components and peritumoral edema could be seen in most pediatric PXAs, and calcification was also not uncommon. The size of the tumor was correlated with the tumor site and radiologic subtype. Maximal safe resection of pediatric PXA is recommended and was shown to be beneficial for seizure control and survival.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2021.04.129DOI Listing
July 2021

Sorption of organic compounds by pyrolyzed humic acids.

Sci Total Environ 2021 Aug 21;781:146646. Epub 2021 Mar 21.

Department of Environmental Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, 866 Yuhangtang Road, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, 866 Yuhangtang Road, Hangzhou 310058, China. Electronic address:

Humic acids (HAs) are frequently subjected to pyrolysis and carbonization by wildfires, which could significantly change the sorption of organic contaminants and their environmental risks in natural system. In previous studies, sorption of organic compounds was investigated for HAs pyrolyzed at temperature below 330 °C, but not for HAs pyrolyzed at higher temperature. Therefore, in this study, sorption of 22 typical organic compounds by HAs pyrolyzed at a series of temperatures from 300 to 700 °C was investigated. Sorption of organic compounds was dominated by nonlinear partition for HAs pyrolyzed at low temperature (e.g., 300 and 400 °C) due to the aliphatic and nonporous structures of pyrolyzed humic acids (PyHAs), while it was dominated by pore-filling adsorption for HAs pyrolyzed at high temperature (e.g., 700 °C) due to the aromatic and porous structures of PyHAs. For HAs pyrolyzed at moderate temperature (e.g., 450, 500 and 600 °C), both nonlinear partition and pore-filling adsorption were responsible for the sorption of organic compounds. Meanwhile, the contribution of pore-filling adsorption to overall sorption increased but the contribution of nonlinear partition decreased with the increasing pyrolytic temperature of PyHAs, attributed to the structure change of PyHAs from aliphatic and nonporous to the aromatic and porous. Moreover, with the increasing pyrolytic temperature of PyHAs, sorption affinity of organic compounds increased, while the change of sorption capacity could be explained by the decrease of nonlinear partition and the increase of pore-filling adsorption. The obtained results could help to evaluate the transport, bioavailability and health risks of organic contaminants in the environment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2021.146646DOI Listing
August 2021

Auxiliary Diagnosis for COVID-19 with Deep Transfer Learning.

J Digit Imaging 2021 04 25;34(2):231-241. Epub 2021 Feb 25.

Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, 519000, Guangdong, China.

To assist physicians identify COVID-19 and its manifestations through the automatic COVID-19 recognition and classification in chest CT images with deep transfer learning. In this retrospective study, the used chest CT image dataset covered 422 subjects, including 72 confirmed COVID-19 subjects (260 studies, 30,171 images), 252 other pneumonia subjects (252 studies, 26,534 images) that contained 158 viral pneumonia subjects and 94 pulmonary tuberculosis subjects, and 98 normal subjects (98 studies, 29,838 images). In the experiment, subjects were split into training (70%), validation (15%) and testing (15%) sets. We utilized the convolutional blocks of ResNets pretrained on the public social image collections and modified the top fully connected layer to suit our task (the COVID-19 recognition). In addition, we tested the proposed method on a finegrained classification task; that is, the images of COVID-19 were further split into 3 main manifestations (ground-glass opacity with 12,924 images, consolidation with 7418 images and fibrotic streaks with 7338 images). Similarly, the data partitioning strategy of 70%-15%-15% was adopted. The best performance obtained by the pretrained ResNet50 model is 94.87% sensitivity, 88.46% specificity, 91.21% accuracy for COVID-19 versus all other groups, and an overall accuracy of 89.01% for the three-category classification in the testing set. Consistent performance was observed from the COVID-19 manifestation classification task on images basis, where the best overall accuracy of 94.08% and AUC of 0.993 were obtained by the pretrained ResNet18 (P < 0.05). All the proposed models have achieved much satisfying performance and were thus very promising in both the practical application and statistics. Transfer learning is worth for exploring to be applied in recognition and classification of COVID-19 on CT images with limited training data. It not only achieved higher sensitivity (COVID-19 vs the rest) but also took far less time than radiologists, which is expected to give the auxiliary diagnosis and reduce the workload for the radiologists.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10278-021-00431-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7906243PMC
April 2021

The Effect of Abusive Supervision on Employees' Work Procrastination Behavior.

Front Psychol 2021 28;12:596704. Epub 2021 Jan 28.

School of Mangement, Hainan University, Haikou, China.

Work procrastination is a retreat behavior associated with negative cognitive experience and it results in great losses to individual as well as organizational development. Understanding the antecedents of employees' work procrastination behavior contributes to lower frequency of its occurrence. This research builds a dual-moderated mediation model from the perspective of cognitive appraisal theory and explored work procrastination behavior of employees subjected to abusive supervision. With 378 valid returned questionnaires, data collected from 32 companies in Beijing, Shanghai, Tianjin, and Chongqing supports our hypotheses. This result has enriched the understanding of work procrastination behavior and provided practical implications to avoide its negative effects.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fpsyg.2021.596704DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7901887PMC
January 2021

Cardiac T1 and T2 Mapping Showed Myocardial Involvement in Recovered COVID-19 Patients Initially Considered Devoid of Cardiac Damage.

J Magn Reson Imaging 2021 08 16;54(2):421-428. Epub 2021 Feb 16.

Radiology Department, The Fifth Affiliated Hospital of Sun-Yat Sen University, Zhuhai, China.

Background: Myocardial injury has been found using magnetic resonance imaging in recovered coronavirus disease 2019 (COVID-19) patients unselected or with ongoing cardiac symptoms.

Purpose: To evaluate for the presence of myocardial involvement in recovered COVID-19 patients without cardiovascular symptoms and abnormal serologic markers during hospitalization.

Study Type: Prospective.

Population: Twenty-one recovered COVID-19 patients and 20 healthy controls (HC).

Field Strength/sequence: 3.0 T, cine, T2-weighted imaging, T1 mapping, and T2 mapping.

Assessment: Cardiac ventricular function includes end-diastolic volume, end-systolic volume, stroke volume, cardiac output, left ventricle (LV) mass, and ejection fraction (EF) of LV and right ventricle (RV), and segmental myocardial T1 and T2 values were measured.

Statistical Tests: Student's t-test, univariate general linear model test, and chi-square test were used for analyses between two groups. Ordinary one-way analyses of variance or Kruskal-Wallis H test were used for analyses between three groups, followed by post-hoc analyses.

Results: Fifteen (71.43%) COVID-19 patients had abnormal magnetic resonance findings, including raised myocardial native T1 (5, 23.81%) and T2 values (10, 47.62%), decreased LVEF (1, 4.76%), and RVEF (2, 9.52%). The segmental myocardial T2 value of COVID-19 patients (49.20 [46.1, 54.6] msec) was significantly higher than HC (48.3 [45.2, 51.7] msec) (P < 0.001), while the myocardial native T1 value showed no significant difference between COVID-19 patients and HC. The myocardial T2 value of serious COVID-19 patients (52.5 [48.1, 57.1] msec) was significantly higher than unserious COVID-19 patients (48.8 [45.9, 53.8] msec) and HC (48.3 [45.2, 51.7]) (P < 0.001). COVID-19 patients with abnormally elevated D-dimer, C-reactive protein, or lymphopenia showed higher myocardial T2 values than without (all P < 0.05).

Data Conclusion: Cardiac involvement was observed in recovered COVID-19 patients with no preexisting cardiovascular disease, no cardiovascular symptoms, and elevated serologic markers of myocardial injury during the whole course of COVID-19.

Level Of Evidence: 1 TECHNICAL EFFICACY: Stage 5.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jmri.27534DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8014142PMC
August 2021

Antifriction Mechanism of Longitudinal Vibration-Assisted Insertion in DBS.

Ann Biomed Eng 2021 Sep 21;49(9):2057-2065. Epub 2021 Jan 21.

School of Mechanical Engineering, Shandong University, Jinan, 250061, China.

Deep brain stimulation (DBS) is an effective treatment for Parkinson's disease. The insertion of brain tissue is an important procedure that affects the whole operation and the sequela. During the insertion process, the friction between the tissue and the needle shaft is the main factor affecting the degree of tissue damage and the accuracy of target location. Vibration-assisted needle insertion has been shown to reduce friction during needle insertion into biological tissue. LuGre model is a friction model that includes coulomb friction and viscous friction between two contact surfaces and accurately describes the Stribeck effect. This paper studies the influence of longitudinal vibration on the friction force during needle insertion. Based on LuGre model, the influence of longitudinal vibration parameters on friction force is discussed. Through experiments on porcine brain tissue and gel phantom, the friction force during insertion and the positive pressure of tissue against the needle under different vibration parameters were investigated. The experiment showed that the vibration can change the friction force by affecting the equivalent friction coefficient and the positive pressure of tissue against the needle. The equivalent friction coefficient showed a specific trend with the change of vibration parameters, while the positive pressure does not change with the vibration parameters.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10439-021-02730-1DOI Listing
September 2021

Adsorption of Organic Compounds by Biomass Chars: Direct Role of Aromatic Condensation (Ring Cluster Size) Revealed by Experimental and Theoretical Studies.

Environ Sci Technol 2021 02 7;55(3):1594-1603. Epub 2021 Jan 7.

School of Environment and Energy, South China University of Technology, Guangzhou 510006, P. R. China.

Biomass chars are a major component of the soil environmental black carbon pool and prepared forms are a potentially useful tool in remediation. A function critical to the roles of both environmental and prepared chars is sorption of organic compounds. Char properties known to control sorption include surface area, porosity, functional group composition, and percent aromatic carbon. Here, we show that sorption affinity (but not maximum capacity) of organic compounds is directly related to the degree of condensation of the aromatic fraction. The Dubinin-Ashtakov characteristic sorption energy (, kJ mol) of 22 compounds on a thermoseries of bamboo chars correlates strongly with the DP/MAS-C NMR-determined bridgehead aromatic carbon fraction (χ), which relates to the mean ring cluster size. Density functional theory-computed binding energy () for five of the compounds on a representative series of polybenzenoid hydrocarbon open-face sheets also correlates positively with χ, leveling off for rings larger than ∼C. The , in turn, correlates strongly with . An increase in with cluster size is also found for sorption, both monolayer and bilayer, between parallel sheets representing slit micropores. The increasing sorption energy with cluster size is shown to be due to increasing cluster polarizability, which strengthens dispersion forces with the sorbate. The findings underscore a previously overlooked explicit role of aromatic condensation in sorption energy, and illustrate the utility of - comparison for predicting sorption.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.est.0c04852DOI Listing
February 2021

In situ Construction of Robust Biphasic Surface Layers on Lithium Metal for Lithium-Sulfide Batteries with Long Cycle Life.

Angew Chem Int Ed Engl 2021 Mar 17;60(13):7267-7274. Epub 2021 Feb 17.

Key Lab for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng, 475004, P. R. China.

Lithium-sulfur (Li-S) batteries have potential in high energy density battery systems. However, intermediates of lithium polysulfides (LiPSs) can easily shuttle to the Li anode and react with Li metal to deplete the active materials and cause rapid failure of the battery. A facile solution pretreatment method for Li anodes involving a solution of metal fluorides/dimethylsulfoxide was developed to construct robust biphasic surface layers (BSLs) in situ. The BSLs consist of lithiophilic alloy (Li M) and LiF phases on Li metal, which inhibit the shuttle effect and increase the cycle life of Li-S batteries. The BSLs allow Li transport and they inhibit dendrite growth and shield the Li anodes from corrosive reaction with LiPSs. Li-S batteries containing BSLs-Li anodes demonstrate excellent cycling over 1000 cycles at 1 C and simultaneously maintain a high coulombic efficiency of 98.2 %. Based on our experimental and theoretical results, we propose a strategy for inhibition of the shuttle effect that produces high stability Li-S batteries.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/anie.202015049DOI Listing
March 2021

Fluorine assembly nanocluster breaks the shackles of immunosuppression to turn the cold tumor hot.

Proc Natl Acad Sci U S A 2020 12 14;117(52):32962-32969. Epub 2020 Dec 14.

State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China

Clinical investigations have shown that a nonimmunogenic "cold" tumor is usually accompanied by few immunopositive cells and more immunosuppressive cells in the tumor microenvironment (TME), which is still the bottleneck of immune activation. Here, a fluorine assembly nanocluster was explored to break the shackles of immunosuppression, reawaken the immune system, and turn the cold tumor "hot." Once under laser irradiation, [email protected] produces sufficient reactive oxygen species (ROS) to fracture the ROS-sensitive linker, thus releasing the cisplatin conjugated PMPt to penetrate into the tumors and kill the regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). Meanwhile, ROS will induce potent immunogenic cell death (ICD) and further promote the accumulation of dendritic cells (DCs) and T cells, therefore not only increasing the infiltration of immunopositive cells from the outside but also reducing the immunosuppressive cells from the inside to break through the bottleneck of immune activation. The [email protected] nanocluster regulates the immune process in TME from negative to positive, from shallow to deep, to turn the cold tumor into a hot tumor and provoke a robust antitumor immune response.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.2011297117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7780000PMC
December 2020

Effect of vibration frequency on frictional resistance of brain tissue during vibration-assisted needle insertion.

Med Eng Phys 2020 12 10;86:35-40. Epub 2020 Oct 10.

School of Mechanical Engineering, Shandong University, Jinan 250061, China; Key Laboratory of High Efficiency and Clean Mechanical Manufacture (Shandong University), Ministry of Education, Jinan 250061, China.

Deep brain stimulation (DBS) is an effective treatment for Parkinson's disease. The cannula insertion process plays an important role in DBS. The friction force during needle insertion influences the precision of the insertion and the degree of damage to the brain tissue. This paper proposes a method of longitudinal vibration assisted insertion to reduce the friction during insertion and improve the effects of the insertion. Cannulas were inserted into twenty eight pig brains at multiple frequencies and fixed amplitudes, and the resulting friction force was measured. On this basis, the LuGre model was used to analyze the friction force trend under vibration-assisted conditions. The frictional forces of vibration-assisted insertion with frequencies ranging from 200-1200 Hz and an amplitude of 1 μm were measured. The results show that the friction between the needle shaft and the tissue is smaller with vibration than without vibration. In this experiment, the friction is reduced by up to 24.43%. The friction force trend of vibration-assisted insertion conforms to the simulation results of the LuGre model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.medengphy.2020.10.003DOI Listing
December 2020

Autonomous climbing: An effective exercise mode with beneficial outcomes of aerobic exercise and resistance training.

Life Sci 2021 Jan 19;265:118786. Epub 2020 Nov 19.

Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, College of Physical Education and Health, East China Normal University, Shanghai 200241, PR China. Electronic address:

Aims: To assess the effects of three specific exercise training modes, aerobic exercise (A), resistance training (R) and autonomous climbing (AC), aimed at proposing a cross-training method, on improving the physical, molecular and metabolic characteristics of mice without many side effects.

Materials And Methods: Seven-week-old male mice were randomly divided into four groups: control (C), aerobic exercise (A), resistance training (R), and autonomous climbing (AC) groups. Physical changes in mice were tracked and analysed to explore the similarities and differences of these three exercise modes. Histochemistry, quantitative real-time PCR (RT-PCR), western blot (WB) and metabolomics analysis were performed to identify the underlying relationships among the three training modes.

Key Findings: Mice in the AC group showed better body weight control, glucose and energy homeostasis. Molecular markers of myogenesis, hypertrophy, antidegradation and mitochondrial function were highly expressed in the muscle of mice after autonomous climbing. The serum metabolomics landscape and enriched pathway comparison indicated that the aerobic oxidation pathway (pentose phosphate pathway, galactose metabolism and fatty acid degradation) and amino acid metabolism pathway (tyrosine, arginine and proline metabolism) were significantly enriched in group AC, suggesting an increased muscle mitochondrial function and protein balance ability of mice after autonomous climbing.

Significance: We propose a new exercise mode, autonomous climbing, as a convenient but effective training method that combines the beneficial effects of aerobic exercise and resistance training.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.lfs.2020.118786DOI Listing
January 2021

A new basal ornithopod dinosaur from the Lower Cretaceous of China.

PeerJ 2020 8;8:e9832. Epub 2020 Sep 8.

Directorate 'Earth and History of Life', Royal Belgian Institute of Natural Sciences, Brussels, Belgium.

A new basal ornithopod dinosaur, based on two nearly complete articulated skeletons, is reported from the Lujiatun Beds (Yixian Fm, Lower Cretaceous) of western Liaoning Province (China). Some of the diagnostic features of nov. gen., nov. sp. are tentatively interpreted as adaptations to a fossorial behavior, including: fused premaxillae; nasal laterally expanded, overhanging the maxilla; shortened neck formed by only six cervical vertebrae; neural spines of the sacral vertebrae completely fused together, forming a craniocaudally-elongated continuous bar; fused scapulocoracoid with prominent scapular spine; and paired ilia symmetrically inclined dorsomedially, partially covering the sacrum in dorsal view. A phylogenetic analysis places as the most basal ornithopod dinosaur described so far. It is tentatively hypothesized that both specimens were suddenly entrapped in a collapsed underground burrow while they were resting, which would explain their perfect lifelike postures and the complete absence of weathering and scavenging traces. However, further behavioural inference remains problematic, because those specimens lack extensive sedimentological and taphonomic data, as it is also the case for most specimens collected in the Lujiatun Beds so far.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7717/peerj.9832DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7485509PMC
September 2020

USP22 Protects Against Myocardial Ischemia-Reperfusion Injury via the SIRT1-p53/SLC7A11-Dependent Inhibition of Ferroptosis-Induced Cardiomyocyte Death.

Front Physiol 2020 21;11:551318. Epub 2020 Oct 21.

Department of Anesthesiology, The Second Hospital of Hebei Medical University, Shijiazhuang, China.

Myocardial ischemia-reperfusion (MI/R) injury is characterized by iron deposition and reactive oxygen species production, which can induce ferroptosis. Ferroptosis has also been proposed to promote cardiomyocyte death. The current study sought to define the mechanism governing cardiomyocyte death in MI/R injury. An animal model of MI/R was established by ligation and perfusion of the left anterior descending coronary artery, and a cellular model of IR was constructed in cardiomyocytes. ChIP assay was then conducted to determine the interaction among USP22, SIRT1, p53, and SLC7A11. Loss- and gain-of-function assays were also conducted to determine the and roles of USP22, SIRT1, and SLC7A11. The infarct size and pathological changes of myocardial tissue were observed using TCC and hematoxylin-eosin staining, and the levels of cardiac function- and myocardial injury-related factors of rats were determined. Cardiomyocyte viability and apoptosis were evaluated , followed by detection of ferroptosis-related indicators (glutathione (GSH), reactive oxygen species, lipid peroxidation, and iron accumulation). USP22, SIRT1, and SLC7A11 expressions were found to be down-regulated, whereas p53 was highly expressed during MI/R injury. USP22, SIRT1, or SLC7A11 overexpression reduced the infarct size and ameliorated pathological conditions, cardiac function, as evidenced by reduced maximum pressure, ejection fraction, maximum pressure rate, and myocardial injury characterized by lower creatine phosphokinase and lactate dehydrogenase levels . Moreover, USP22, SIRT1, or SLC7A11 elevation contributed to enhanced cardiomyocyte viability and attenuated ferroptosis-induced cell death , accompanied by increased GSH levels, as well as decreased reactive oxygen species production, lipid peroxidation, and iron accumulation. Together, these results demonstrate that USP22 overexpression could inhibit ferroptosis-induced cardiomyocyte death to protect against MI/R injury the SIRT1/p53/SLC7A11 association.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2020.551318DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7609439PMC
October 2020

Design, synthesis and antitumor evaluation of novel 5-methylpyrazolo[1,5-a]pyrimidine derivatives as potential c-Met inhibitors.

Bioorg Chem 2020 11 8;104:104356. Epub 2020 Oct 8.

Key Laboratory of Molecular Target & Clinical Pharmacology, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou 511436, Guangdong, PR China. Electronic address:

A series of novel 5-methylpyrazolo[1,5-a]pyrimidine derivatives (10a-10x) were designed, synthesized, and evaluated for their in vitro inhibitory activities against c-Met kinase and antiproliferative activities against the SH-SY5Y, MDA-MB-231, A549, and HepG2 cell lines. Most of the compounds remarkably inhibited c-Met kinase and showed moderate to good cytotoxicity and selectivity toward the four cancer cell lines. Among them, compounds 10b and 10f were the two most potent selective c-Met inhibitors with half-maximal inhibitory concentration (IC) values of 5.17 ± 0.48 nM and 5.62 ± 0.78 nM, respectively, and suppression abilities comparable with the positive control cabozantinib. Cell proliferation assay further demonstrated that the two most promising compounds 10a and 10b also showed good cytotoxicity and selectivity toward MDA-MB-231 cells, with IC values of 26.67 ± 2.56 μM and 26.83 ± 2.41 μM, respectively. Compounds 10f and 10g showed cytotoxicity and selectivity toward A549 cells, with IC values of 20.20 ± 2.04 μM and 21.65 ± 1.58 μM, respectively. All antiproliferative activities were within the range of those of cabozantinib. Notably, these compounds presented relatively low hepatotoxicity compared with reference drugs. Moreover, the preliminary structure-activity relationship and docking studies revealed that replacement of a nitrogen-containing heterocycle on the R (block A) group might improve the c-Met kinase inhibitory and antiproliferative effects in MDA-MB-231 cells, whereas displacement by a substituted benzene ring, especially for the p-fluorophenyl or 4-fluoro-3-methoxyphenyl moiety, on the R group enhanced cytotoxicity toward A549 cells. Together, these results suggest that 10b and 10f are promising compounds and provide a basis for their development as new antitumor agents.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bioorg.2020.104356DOI Listing
November 2020

Assessment of patient-based real-time quality control algorithm performance on different types of analytical error.

Clin Chim Acta 2020 Dec 28;511:329-335. Epub 2020 Oct 28.

Department of Laboratory Medicine, Zhongshan Hospital, Fudan University, 180 Fenglin Rd, Shanghai 200032, China. Electronic address:

Background: Patient-based real-time quality control (PBRTQC) has gained attention because of its potential to detect analytical errors in situations wherein internal quality control is less effective. Multiple PBRTQC algorithms have been proposed. However, there is a lack of comprehensive comparison of the performance of PBRTQC algorithms on different types of analytical errors. Thus, a comparative study was conducted.

Methods: The performance of six different PBRTQC algorithms was evaluated on three types of analytical errors using 906,552 test results for outpatient serum sodium, chloride, alanine aminotransferase, and creatinine at the Department of Laboratory Medicine at Zhongshan Hospital, Fudan University in 2019. The performance results were compared and assessed.

Results: The moving average, moving median, exponentially weighted moving average, and moving quartiles performed similarly for effectively detecting constant errors (CE) and proportional errors (PE) but not random errors (RE). The moving sum of positive patients and moving standard deviation could detect RE for serum sodium and chlorides but performed poorly on detecting the CE and PE.

Conclusions: This study demonstrated the importance of assessing the potential source of error of a particular analyte and the corresponding type of analytical error before choosing a quality control algorithm for implementation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cca.2020.10.006DOI Listing
December 2020

Financial performance of hospitals: A critical obligation of corporate governance dimensions.

Int J Health Plann Manage 2020 Nov 4;35(6):1468-1485. Epub 2020 Sep 4.

Ghana Health Service, Central Regional Office, Cape Coast, Ghana.

Background: This paper aims to investigate the effects of corporate governance mechanisms on the financial performance of hospitals. The statement, "good corporate governance" has been incorporated in the health care sector over the last decade, as an element to improve financial performance.

Methods: The researchers relied on both primary and secondary data in the study. For the primary data, the authors used structured and nonstructured questionnaires to obtain data from 125 hospitals. The secondary data used emanated from board meetings, financial statements and relevant reports of the selected hospitals from 2010 to 2017. However, the data was then sorted out to get the required information on Chief Executive Officer (CEO) presence, board relationship, governance dynamics, gender diversity and financial performance.

Results: On the basis of empirical evidence provided in this study, the results show that the Independent Directors (INDPDR) variable has a positive effect on Return on Assets and Net Profit Margin and also a high statistically significant value of 0.000 for both performance measures. This is an indication that the variable, INDPDR, is highly capable of improving hospital financial performance. From our studies, Board Size and CEO Duality exhibited a negative relationship with the financial performance measures.

Conclusions: Every hospital needs money to maintain a standard health facility and to sustain in operation. However, the inclusion of board of directors improves hospital financial management and enhances performance. Corporate governance mechanisms influence the behavior of health systems in ways that are associated with financial performance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/hpm.3049DOI Listing
November 2020

miR-30e-3p Promotes Cardiomyocyte Autophagy and Inhibits Apoptosis via Regulating Egr-1 during Ischemia/Hypoxia.

Biomed Res Int 2020 17;2020:7231243. Epub 2020 Aug 17.

Department of Cardiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China.

Background: Microvascular obstruction (MVO) can result in coronary microcirculation embolism and myocardial microinfarction. Myocardial injury induced by MVO is characterized by continuous ischemia and hypoxia of cardiomyocytes. Autophagy and apoptosis are closely associated with various cardiovascular diseases. Based on our previous study, we observed a decrease in miR-30e-3p expression and an increase in Egr-1 expression in a rat coronary microembolization model. However, the specific function of miR-30e-3p in regulating autophagy and apoptosis in an ischemia/hypoxia (IH) environment remains to be deciphered. We exposed cardiomyocytes to an IH environment and then determined whether miR-30e-3p was involved in promoting cardiomyocyte autophagy and inhibiting apoptosis by regulating Egr-1.

Methods: Cardiomyocytes were isolated from rats for our study. miR-30e-3p was either overexpressed or inhibited by transfection with lentiviral vectors into cardiomyocytes. 3-Methyladenine (3-MA) was used to inhibit autophagy. RT-qPCR and western blotting were used to determine the expression levels of miR-30e-3p, Egr-1, and proteins related to the autophagy and apoptosis process. Autophagic vacuoles and autophagic flux were evaluated using transmission electron microscopy (TEM) and confocal microscopy, respectively. Cardiomyocyte viability was evaluated using the MTS assay. Cell injury was assessed by lactate dehydrogenase (LDH) leakage, and apoptosis was determined by flow cytometry.

Results: Both miR-30e-3p expression and autophagy were significantly inhibited, and apoptosis was increased in cardiomyocytes after 9 hours of IH exposure. Overexpression of miR-30e-3p increased autophagy and inhibited apoptosis, as well as suppressed Egr-1 expression and decreased cell injury. In addition, inhibition of miR-30e-3p reduced autophagy and increased apoptosis and cell injury.

Conclusions: miR-30e-3p may be involved in promoting cardiomyocyte autophagy and inhibiting apoptosis by indirectly regulating Egr-1 expression in an IH environment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2020/7231243DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7448244PMC
May 2021

The integrated genomic and epigenomic landscape of brainstem glioma.

Nat Commun 2020 06 17;11(1):3077. Epub 2020 Jun 17.

Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Nan Si Huan Xi Lu 119, Fengtai District, 100070, Beijing, China.

Brainstem gliomas are a heterogeneous group of tumors that encompass both benign tumors cured with surgical resection and highly lethal cancers with no efficacious therapies. We perform a comprehensive study incorporating epigenetic and genomic analyses on a large cohort of brainstem gliomas, including Diffuse Intrinsic Pontine Gliomas. Here we report, from DNA methylation data, distinct clusters termed H3-Pons, H3-Medulla, IDH, and PA-like, each associated with unique genomic and clinical profiles. The majority of tumors within H3-Pons and-H3-Medulla harbors H3F3A mutations but shows distinct methylation patterns that correlate with anatomical localization within the pons or medulla, respectively. Clinical data show significantly different overall survival between these clusters, and pathway analysis demonstrates different oncogenic mechanisms in these samples. Our findings indicate that the integration of genetic and epigenetic data can facilitate better understanding of brainstem gliomagenesis and classification, and guide future studies for the development of novel treatments for this disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-020-16682-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7299931PMC
June 2020

Boosting the Alkali/Heavy Metal Poisoning Resistance for NO Removal by Using Iron-Titanium Pillared Montmorillonite Catalysts.

J Hazard Mater 2020 11 21;399:122947. Epub 2020 May 21.

Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai, 200444, China. Electronic address:

It is still a big challge to improve the alkali and heavy metal resistance of deNO catalysts for selective catalytic reduction (SCR) of NO with NH. In this study, a novel catalyst developed by pillaring montmorillonite with iron and titanium (Fe-Ti-MMT) was proposed. It is quite interesting that high resistance to alkaline and heavy metals has been demonstrated by using Fe-Ti-MMT catalysts. It has been demonstrated that the specific pillaring synthesis procedure and further addition of the Ti pillared sites greatly contributed to the wide active temperature window and enhanced the resistance to alkali and heavy metal. The higher ratio of active Fe species, more active acid sites, and enhanced ammonia adsorption indicated the remarkable activity as well as K and Pb resistance. Moreover, the K and Pb poisons would promote the generation of active adsorbed NO species on the Fe-Ti-MMT but induce the formation of stable inactive ones on that of Fe-MMT, which greatly tuned the reaction pathways and improved the reaction rate for Ti modified Fe pillared MMT catalysts. The strategy of incorporating Ti into the Fe pillared MMT catalysts strongly provides a novel inspiration for keeping excellent NH-SCR performance in the presence of alkali/heavy metal for NO removal.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2020.122947DOI Listing
November 2020

Nonlinear sorption of phenols and anilines by organobentonites: Nonlinear partition and space limitation for partitioning.

Sci Total Environ 2020 Sep 22;736:139609. Epub 2020 May 22.

Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China. Electronic address:

Organobentonites, i.e., bentonites coated with surfactants such as cetyltrimethylammonium (CTAB), are superior and low-cost sorbents for removal of organic contaminants from wastewater. Nonlinear sorption of polar organic compounds such as phenols and anilines by organobentonites were widely observed and interpreted by adsorption mechanism. However, in this study, it was observed that the nonlinear sorption of phenols and anilines by CTAB coated bentonites (CTAB-bentonites) should be attributed to nonlinear partition mechanism with the additional space limitation in CTAB-bentonites for nonlinear partitioning, rather than adsorption mechanism. This nonlinear partition mechanism is supported by that (i) organobentonites is a partition medium, identified by the linear isotherms of polycyclic aromatic hydrocarbons (PAHs) and nitrobenzenes; (ii) sorption coefficients (logK), the ratio of adsorbed amount (q) to equilibrium concentration (C), and Dubinin-Ashtakhov (DA) model fitted sorption capacity (logQ) of organic compounds, by a given CTAB-bentonite, are positively correlated with their octanol-water distribution coefficients (logK) and solubility in octanol (logS) respectively; (iii) logK and logQ of a given organic compound by CTAB-bentonites are positively correlated with organic carbon contents (f) of CTAB-bentonites, but not specific surface area. Specific interaction (i.e., hydrogen-bonding interaction), in addition to van der Waals force, is responsible for the nonlinear partitioning of phenols and anilines into CTAB-bentonites, because of the positively linear relationship between DA model fitted sorption affinity (E) and hydrogen-bonding donor parameter (α) of organic compounds. These results could help the recognizing of the nonlinear sorption behaviors of organic compounds by organobentonites and promote their environmental applications in wastewater treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2020.139609DOI Listing
September 2020

Segmentation of pulmonary nodules in CT images based on 3D-UNET combined with three-dimensional conditional random field optimization.

Med Phys 2020 Sep 4;47(9):4054-4063. Epub 2020 Jun 4.

School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, People's Republic of China.

Purpose: Pulmonary nodules are a potential manifestation of lung cancer. In computer-aided diagnosis (CAD) of lung cancer, it is of great significance to extract the complete boundary of the pulmonary nodules in the computed tomography (CT) scans accurately. It can provide doctors with important information such as tumor size and density, which assist doctors in subsequent diagnosis and treatment. In addition to this, in the molecular subtype and radiomics of lung cancer, segmentation of lung nodules also plays a pivotal role. Existing methods are difficult to use only one model to simultaneously treat the boundaries of multiple types of lung nodules in CT images.

Method: In order to solve the problem, this paper proposed a three-dimensional (3D)-UNET network model optimized by a 3D conditional random field (3D-CRF) to segment pulmonary nodules. On the basis of 3D-UNET, the 3D-CRF is used to optimize the sample output of the training set, so as to update the network weights in training process, reduce the model training time, and reduce the loss rate of the model. We selected 936 sets of pulmonary nodule data for the lung image database consortium and image database resource initiative (LIDC-IDRI) database to train and test the model. What's more, we used clinical data from partner hospitals for additional validation.

Results And Conclusions: The results show that our method is accurate and effective. Particularly, it shows more significance for the optimization of the segmentation of adhesive pulmonary nodules (the juxta-pleural and juxta-vascular nodules) and ground glass pulmonary nodules (GGNs).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/mp.14248DOI Listing
September 2020
-->