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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(4): 588-596, 2022 Jul.
Article in Chinese | MEDLINE | ID: mdl-35871728

ABSTRACT

Objective: To explore the prognostic factors of adult ventricle glioma (AVG) and to construct and evaluate a survival-related prognostic nomogram model, which could provide further reference for the clinical management of AVG patients. Methods: The patients covered in the study were selected from the Surveillance Epidemiology and End Results (SEER) database (1973-2016). They all had definite histological diagnosis of AVG. They were assigned randomly to the training cohort and the validation cohort by random number table at a 2/1 ratio. Survival analysis was performed by Kaplan-Meier analysis. Cox regression analysis was employed to determine the independent prognostic factors for overall survival (OS) and cancer-specific survival (CSS). Then, integrating the basic characteristics of patients, the survival-related nomogram predictive model for OS and CSS in the training cohort was constructed, respectively. After that, internal cross validation and external validation of the model were carried out with the training cohort and the validation cohort in succession. The authenticity and reliability of the nomogram model were evaluated by calculating the concordance index (C-index). Calibration plots were constructed to assess the agreement between the predicted values and the observed values in the training cohort and the validation cohort. Results: A total of 369 AVG patients, including 218 males and 151 females, were included. The median age of the patients was 53. According to the WHO classification of gliomas, 66 (17.9%) patients had grade Ⅱ gliomas, 73 (19.8%) had grade Ⅲ gliomas, and 230 (62.3%) had grade Ⅳ gliomas. Regarding the extent of resection (EOR), 59 (16.0%) had gross total resection (GTR) and 145 (39.3%) had subtotal resection (STR) or partial resection (PR). Of all the patients, 167 (45.3%) received postoperative radiotherapy and 143 (38.8%) received postoperative chemotherapy. Patients were randomized into the training cohort ( n=246) and the validation cohort ( n=123), and there was no significant difference ( P>0.05) in the basic clinical characteristics between the training cohort and the validation cohort. In the training cohort, Cox regression analysis revealed that the independent prognostic factors for OS and CSS included age≥65, grades Ⅲ and Ⅳ according to the WHO classification of gliomas, and not receiving radiotherapy. Furthermore, 5 variables, including age, gender, WHO grades, surgery, and radiotherapy, were used to construct the nomogram model for predicting 6-month, 1-year, and 2-year OS and CSS. The results of internal cross validation in the training cohort showed that the C-indexes of OS and CSS were 0.758 and 0.765, respectively. The external validation results of the validation cohort showed that the C-indexes of OS and CSS were 0.733 and 0.719, respectively. Calibration plots for 6-month, 1-year, and 2-year OS in the training cohort showed relatively good agreement, while in the validation cohort the agreement was relatively low. The 6-month, 1-year, and 2-year CSS calibration plots had results similar to the calibration plots of OS. Conclusion: This nomogram predictive model of OS and CSS showed moderately reliable predictive performance, providing helpful reference information for clinicians to make quick and simple assessment of the survival probability of AVG patients.


Subject(s)
Glioma , Nomograms , Adult , Aged , Female , Humans , Male , Prognosis , Reproducibility of Results , SEER Program
2.
Langmuir ; 38(8): 2601-2607, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-35179906

ABSTRACT

This article investigates the maximum spreading of ferrofluid droplets impacting on a hydrophobic surface under nonuniform magnetic fields. A generalized model for scaling the maximum spreading is developed. It is observed that, if the magnetic field strength is zero, a ferrofluid droplet not only demonstrates similar spreading dynamics as the water droplet but also obeys the same scaling law for the maximum spreading factor. Therefore, this article emphasizes the effects of magnetic field strength. In this regard, a dimensionless parameter (Nm) is introduced as the ratio between inertial force and Kelvin force, with an assumption that the kinetic energy mainly transforms to thermal energy. This parameter allows us to rescale all experimental data on a single curve with the Padé approximant, which is applicable to a wide range of impact velocities and magnetic field strengths.

3.
J Environ Sci (China) ; 108: 1-7, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34465424

ABSTRACT

The distribution and chemical speciation of arsenic (As) in different sized atmospheric particulate matters (PMs), including total suspended particles (TSP), PM10, and PM2.5, collected from Baoding, China were analyzed. The average total mass concentrations of As in TSP, PM10, and PM2.5 were 31.5, 35.3, and 54.1 µg/g, respectively, with an order of PM2.5 >PM 10 > TSP, revealing that As is prone to accumulate on fine particles. Due to the divergent toxicities of different As species, speciation analysis of As in PMs is further conducted. Most of previous studies mainly focused on inorganic arsenite (iAsIII), inorganic arsenate (iAsV), monomethylarsonate (MMA), and dimethylarsinate (DMA) in PMs, while the identification and sensitive quantification of trimethylarsine oxide (TMAO) were rarely reported. In this study, a high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry system was optimized for As speciation including TMAO in PMs. An anion exchange column was used to separate MMA, DMA and iAsV, while a cation exchange column to separate TMAO and iAsIII. Results showed that iAsV was the dominate component in all the samples, corresponding to a portion of 79.2% ± 9.3% of the total extractable species, while iAsIII, TMAO and DMA made up the remaining 21%. Our study demonstrated that iAsIII accounted for about 14.4% ± 11.4% of the total extracted species, with an average concentration of 1.7 ± 1.6 ng/m3. It is worth noting that TMAO was widely present in the samples (84 out of 97 samples), which supported the assumption that TMAO was ubiquitous in atmospheric particles.


Subject(s)
Arsenic , Arsenicals , Arsenic/analysis , Arsenicals/analysis , Cacodylic Acid , China , Chromatography, High Pressure Liquid , Particulate Matter/analysis
4.
Phys Fluids (1994) ; 33(4): 042004, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33897247

ABSTRACT

In the present study, the magnetic field induced self-assembly processes of magnetic microparticles in an aqueous liquid (the pure magnetic fluid) and nonmagnetic microparticles in ferrofluid (the inverse magnetic fluid) are experimentally investigated. The microparticles are formed into chain-like microstructures in both the pure magnetic fluid and the inverse magnetic fluid by applying the external magnetic field. The fluorescence parameters of these self-assembled chain-like microstructures are measured and compared to those without the effect of magnetic field. It is found that the fluorescence in the pure magnetic fluid is weakened, because the scattering and illuminating areas are reduced in the microstructures. On the contrary, the fluorescence in the inverse magnetic fluid is enhanced, because more fluorescent nonmagnetic microparticles are enriched and become detectable under the effect of the magnetic dipole force and the magnetic levitational force, and their unnecessary scattering can be absorbed by the surrounding ferrofluid. The average enhancement of the fluorescence area ratio in the inverse magnetic fluid with 3 µm nonmagnetic microparticles reaches 112.92%. The present work shows that the inverse magnetic fluid has advantages such as low cost, no scattering effect, stable fluorescence intensity, and relatively low magnetic resistance. In the end, a prototype design for the novel detection of coronavirus disease 2019 based on the magnetic field induced self-assembly in the inverse magnetic fluid is proposed, which could support the epidemic prevention and control.

5.
Ecotoxicol Environ Saf ; 192: 110249, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32044603

ABSTRACT

Fractions, bioavailability, health risks of fine particulate maters (PM2.5)-bound potentially toxic elements (PTEs) (Pb, Cd, Cr, Cu and Zn) were investigated before and after coal limiting in Baoding city. The winter PM2.5 samples were collected at different functional areas such as residential area (RA), industrial area (IA), suburb (SB), street (ST) and Botanical Garden Park (BG) in 2016 (coal dominated year) and 2017 (gas dominated year). The fractions and bioavailability of PTEs were determined and evaluated based on BCR sequential extraction. Health risks through inhalation exposure were evaluated by US EPA health risk assessment model. The results from different years and functional areas were compared and discussed. The fractions and bioavailability of PM2.5-bound PTEs varied with functional areas. The percentages of cadmium (Cd) and zinc (Zn) in acid-soluble fraction (F1-Cd and F1-Zn) to the total amount of Cd and Zn were low in BG samples (p < 0.05). Bioavailability of Cd were high in SB samples (p < 0.05). Total contents of PM-bound PTEs in 2017 generally decreased compared with 2016. The differences of fraction and bioavailability between 2016 and 2017 depended on the elements and areas. Higher proportions of copper (Cu) in acid-soluble fraction (F1-Cu) and bioavailability of Cu (p < 0.05) were found in 2017 samples. Significant differences were found just at IA and RA for Pb, Cd and Zn. Our results indicated that the health risks from inhalation exposure for PTEs in PM2.5 declined about 11%-52% after the coal limiting in this city.


Subject(s)
Air Pollutants/analysis , Coal , Metals, Heavy/analysis , Particulate Matter/analysis , Adult , Air Pollutants/toxicity , Cadmium/analysis , Cadmium/toxicity , Child , Chromium/analysis , Chromium/toxicity , Cities , Copper/analysis , Copper/toxicity , Environmental Monitoring , Humans , Inhalation Exposure , Lead/analysis , Lead/toxicity , Metals, Heavy/toxicity , Particulate Matter/toxicity , Risk Assessment , Seasons , Zinc/analysis , Zinc/toxicity
6.
Environ Pollut ; 259: 113881, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31952103

ABSTRACT

Coal-Gas replacement project has been implemented to decrease haze pollution in China in recent years. Airborne arsenic (As) mostly originates from coal burning processes. It is noteworthy to compare the distribution of arsenic fraction in PM2.5 before and after coal-gas replacement. Eighty PM2.5 samples were collected in Baoding in December 2016 (coal dominated year) and December 2017 (gas dominated year) at different functional areas including residential area (RA), industrial area (IA), suburb (SB), roadside (ST) and Botanical Garden Park (BG). The fraction, bioavailability and health risk of As in the PM2.5 samples were investigated and compared between these two years. Arsenic was mainly distributed in the non-specifically sorbed fraction (F1) and the residual fraction (F5). However, the proportion of F1 to the total As in 2017 was higher than that in 2016, while the proportion of As in the amorphous and poorly-crystalline hydrous oxides of Fe and Al fraction (F3) in 2017 was lower. The distributions of fraction and bioavailability showed temporal and spatial characteristics. The total concentration and bioavailability of As in SB and IA were significantly higher than those in RA, ST and BG. The BF (Bioavailability Factor) values of As ranged from 0.30 to 0.61. Health risk assessment indicated that the hazard quotient (HQ) and carcinogenic risk (CR) of As in PM2.5 significantly decreased after coal-gas replacement.


Subject(s)
Air Pollutants , Arsenic , Coal , Environmental Monitoring , Natural Gas , Particulate Matter , Air Pollutants/analysis , Arsenic/analysis , China , Coal/analysis , Natural Gas/analysis , Particulate Matter/chemistry , Risk Assessment
7.
Sci Rep ; 9(1): 18812, 2019 Dec 11.
Article in English | MEDLINE | ID: mdl-31827159

ABSTRACT

A new type of modular metamaterials with reprogrammable mechanical properties is proposed based on the multistability in decoupled units. This metamaterial consists of periodically arranged foldable obelisk-like (FO) units, and each unit has three interchangeable states: two different soft states and a stiff state. Therefore, such metamaterial can possess various mechanical properties with different state combinations of units. Both theoretical and experimental investigations are conducted to understand the multistability in one unit and the reprogrammed mechanical properties in a two-dimensional tessellation. Additionally, we investigate the inverse question that whether the identical force response can be generated with different geometrical design of the metamaterial and propose a way to build 3D metamaterials with intended architectures. This work establishes general principles for designing mechanical metamaterials with independently transformable modules, and opens new avenues for various potential applications such as: self-locking materials, impact mitigation and stiffness transformation materials.

8.
Ying Yong Sheng Tai Xue Bao ; 27(2): 335-44, 2016 Feb.
Article in Chinese | MEDLINE | ID: mdl-27396103

ABSTRACT

The carbon flux of subtropical bamboo forest ecosystem was continuously measured using eddy covariance technique in Anji County of Zhejiang Province, China. The monthly net ecosystem productivity (NEP), ecosystem respiration (Re) and gross ecosystem productivity (GEP) data from 2011 to 2013 were selected to analyze the impacts of seasonal high temperature and drought on the carbon flux of bamboo forest ecosystem. The results showed that there were big differences among annual NEP of bamboo forest from 2011 to 2013. Because of the asynchronization of precipitation and heat, the seasonal high temperature and drought in July and August of 2013 caused significant decline in NEP by 59.9% and 80.0% when compared with the same months in 2011. Correlation analysis of the NEP, Re, GEP and environmental factors suggested that the atmosphere temperatures were significantly correlated with Re and GEP in 2011 and 2013 (P<0.05). However, to air and soil moisture, Re and GEP had different responses, that was, GEP was more vulnerable by the decrease of the soil moisture compared with Re. Besides, the raising of saturation vapour pressure promoted the Re modestly but inhibited the GEP, which was supposed to be the main reason for NEP decrease of bamboo forest ecosystem in Anji, from July to August in 2013.


Subject(s)
Carbon Cycle , Forests , Hot Temperature , Poaceae/growth & development , Atmosphere , China , Droughts , Seasons , Soil
9.
Ying Yong Sheng Tai Xue Bao ; 27(1): 1-8, 2016 Jan.
Article in Chinese | MEDLINE | ID: mdl-27228586

ABSTRACT

The old-growth, multiple ages, multispecies natural forest has played an important role in terrestrial ecosystem dynamics model and the global carbon budget. However, carbon fluxes of old forests in subtropical regions are rarely reported in China. In the present study, the CO2 flux of an old-growth subtropical evergreen and deciduous broad-leaved mixed forest was observed using eddy covariance technique in Tianmu Mountain of Zhejiang Province. Based on the data sets which were observed from July 2013 to June 2014, the variations of net ecosystem exchange (NEE), eco-system respiration (Re), and gross ecosystem exchange (GEE) were analyzed. The results showed that during the study period, the monthly NEE all had a negative value (acted as a carbon sink) except for December and February (acted as a carbon source). The average monthly NEE was -61.52 g C · m⁻², the monthly carbon sequestration showed a double-peak curve and the maximum carbon sink was -149.40 g C · m⁻², which occurred in June while the maximum carbon source was 23.45 g C · m⁻², which occurred in February. The maximum of monthly mean CO2 flux occurred in June with a value of -0.98 mg · m⁻² · s⁻¹, while the minimum value occurred in December with a value of -0.35 mg · m⁻² · s⁻¹. The NEE at the time point of positive and negative conversion had typical seasonal characteristics. The yearly NEE, Re, and GEE were -738.18, 931.05 and -1669.23 g C · m⁻², respectively. Compared with other forest ecosystems located at the similar latitude, the carbon fixation of the old-growth forest was larger, likely due to its complicated structure within the canopy and the presence of young-growth regeneration and successional stands. This showed that other than in carbon neutral, old-growth forests of Tianmu Mountain in subtropical China had a strong capability in carbon sequestration.


Subject(s)
Carbon Dioxide/analysis , Carbon Sequestration , Forests , Carbon , China , Environmental Monitoring
11.
J Org Chem ; 80(1): 90-8, 2015 Jan 02.
Article in English | MEDLINE | ID: mdl-25426845

ABSTRACT

A CuI-catalyzed tandem reaction of 5-(2-bromoaryl)-N-aryl-1H-pyrazol-3-amines with active acetonitrile derivatives to prepare pyrazolo[5,1-a]isoquinolines in good to excellent yields has been successfully developed under mild conditions with heterocyclic ketene aminals (HKAs) as new ligands. This is the first time HKAs have been used as ligands for copper-catalyzed coupling reactions.


Subject(s)
Amines/chemistry , Copper/chemistry , Ethylenes/chemistry , Heterocyclic Compounds/chemistry , Isoquinolines/chemical synthesis , Ketones/chemistry , Catalysis , Isoquinolines/chemistry , Ligands , Molecular Structure
12.
J Dermatol ; 41(7): 642-4, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24807120

ABSTRACT

Favre-Racouchot syndrome (FRS) is a disorder consisting of solar elastosis with the presence of multiple cysts and open comedones. Although the exact mechanism of the condition is not known, FRS has been specifically connected to sun exposure, smoking and radiation exposure. The histological changes present in FRS reveal an atrophic epidermis and large masses of keratinous material, causing follicular plugging, as well as solar elastotic changes and possible basophilic degeneration of connective tissue. Herein, we report an unusual case of FRS concurrent with chronic granulomatous reaction and review relevant published works.


Subject(s)
Facial Dermatoses/complications , Granulomatous Disease, Chronic/complications , Aged , Diagnosis, Differential , Facial Dermatoses/pathology , Granulomatous Disease, Chronic/pathology , Humans , Male
13.
Asian Pac J Cancer Prev ; 15(2): 911-5, 2014.
Article in English | MEDLINE | ID: mdl-24568518

ABSTRACT

AIM: This study was to evaluate the effect of whole brain radiation (WBRT) combined with stereotactic radiotherapy (SRS) versus stereotactic radiotherapy alone for patients with brain metastases using a meta- analysis. MATERIALS AND METHODS: We searched PubMed, EMBASE, Cochrane Library from their inception up to October 2013. Randomized controlled trials involving whole brain radiation combined with stereotactic radiotherapy versus stereotactic radiotherapy alone for brain metastases were included. Statistical analyses were performed using RevMan5.2 software. RESULTS: Four randomized controlled trials including 903 patients were included. The meta-analysis showed statistically significant lowering of the local recurrence rate (OR=0.29, 95%CI: 0.17~0.49), new brain metastasis rate (OR=0.45, 95%CI: 0.28~0.71) and symptomatic late neurologic radiation toxicity rate (OR=3.92, 95%CI: 1.37~11.20) in the combined group. No statistically significant difference existed in the 1-year survival rate (OR=0.78, 95%CI: 0.60~1.03). CONCLUSIONS: The results indicate that whole brain radiotherapy combined with stereotactic radiotherapy has advantages in local recurrence and new brain metastasis rates, but stereotactic radiotherapy alone is associated with better neurological function. However, as the samples included were not large, more high-quality, large-sample size studies are necessary for confirmation.


Subject(s)
Brain Neoplasms/radiotherapy , Brain Neoplasms/surgery , Cranial Irradiation/methods , Radiosurgery/methods , Combined Modality Therapy , Humans , Prognosis , Randomized Controlled Trials as Topic
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(4 Pt 2): 046713, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19518386

ABSTRACT

In this paper, a lattice Boltzmann model for simulating temperature-sensitive ferrofluids is presented. The lattice Boltzmann equation for modeling the magnetic field is formulated using a scalar magnetic potential. Introducing a time derivative into the original elliptic equation for the scalar potential leads to an advection-diffusion equation, with an effective velocity determined by the temperature gradient. The time derivative is multiplied by an adjustable preconditioning parameter to ensure that the lattice Boltzmann solution remain close to a solution of the original elliptic equation for the scalar potential. To test the present lattice Boltzmann model, numerical simulations for the thermomagnetic nature convection of the ferrofluids in a cubic cavity are carried out. Good agreement between the obtained results and experimental data shows that the present lattice Boltzmann model is promising for studying temperature-sensitive ferrofluid flows.

15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(3 Pt 2): 036711, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17930365

ABSTRACT

It is well known that the Navier-Stokes equations cannot adequately describe gas flows in the transition and free-molecular regimes. In these regimes, the Boltzmann equation (BE) of kinetic theory is invoked to govern the flows. However, this equation cannot be solved easily, either by analytical techniques or by numerical methods. Hence, in order to efficiently maneuver around this equation for modeling microscale gas flows, a kinetic lattice Boltzmann method (LBM) has been introduced in recent years. This method is regarded as a numerical approach for solving the BE in discrete velocity space with Gauss-Hermite quadrature. In this paper, a systematic description of the kinetic LBM, including the lattice Boltzmann equation, the diffuse-scattering boundary condition for gas-surface interactions, and definition of the relaxation time, is provided. To capture the nonlinear effects due to the high-order moments and wall boundaries, an effective relaxation time and a modified regularization procedure of the nonequilibrium part of the distribution function are further presented based on previous work [Guo et al., J. Appl. Phys. 99, 074903 (2006); Shan et al., J. Fluid Mech. 550, 413 (2006)]. The capability of the kinetic LBM of simulating microscale gas flows is illustrated based on the numerical investigations of micro Couette and force-driven Poiseuille flows.

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