Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
BMC Med Res Methodol ; 23(1): 108, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37131135

RESUMO

BACKGROUND: Despite the extensive research on data mining algorithms, there is still a lack of a standard protocol to evaluate the performance of the existing algorithms. Therefore, the study aims to provide a novel procedure that combines data mining algorithms and simplified preprocessing to establish reference intervals (RIs), with the performance of five algorithms assessed objectively as well. METHODS: Two data sets were derived from the population undergoing a physical examination. Hoffmann, Bhattacharya, Expectation Maximum (EM), kosmic, and refineR algorithms combined with two-step data preprocessing respectively were implemented in the Test data set to establish RIs for thyroid-related hormones. Algorithm-calculated RIs were compared with the standard RIs calculated from the Reference data set in which reference individuals were selected following strict inclusion and exclusion criteria. Objective assessment of the methods is implemented by the bias ratio (BR) matrix. RESULTS: RIs of thyroid-related hormones are established. There is a high consistency between TSH RIs established by the EM algorithm and the standard TSH RIs (BR = 0.063), although EM algorithms seems to perform poor on other hormones. RIs calculated by Hoffmann, Bhattacharya, and refineR methods for free and total triiodo-thyronine, free and total thyroxine respectively are close and match the standard RIs. CONCLUSION: An effective approach for objectively evaluating the performance of the algorithm based on the BR matrix is established. EM algorithm combined with simplified preprocessing can handle data with significant skewness, but its performance is limited in other scenarios. The other four algorithms perform well for data with Gaussian or near-Gaussian distribution. Using the appropriate algorithm based on the data distribution characteristics is recommended.


Assuntos
Glândula Tireoide , Hormônios Tireóideos , Adulto , Humanos , Pessoa de Meia-Idade , Valores de Referência , Mineração de Dados , Tireotropina
2.
Environ Sci Technol ; 57(17): 7063-7073, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37018050

RESUMO

Pyrolysis of oily sludge (OS) is a feasible technology to match the principle of reduction and recycling; however, it is difficult to confirm the feasible environmental destination and meet the corresponding requirements. Therefore, an integrated strategy of biochar-assisted catalytic pyrolysis (BCP) of OS and residue utilization for soil reclamation is investigated in this study. During the catalytic pyrolysis process, biochar as a catalyst intensifies the removal of recalcitrant petroleum hydrocarbons at the expense of liquid product yield. Concurrently, biochar as an adsorbent can inhibit the release of micromolecular gaseous pollutants (e.g. HCN, H2S, and HCl) and stabilize heavy metals. Due to the assistance of biochar, pyrolysis reactions of OS are more likely to occur and require a lower temperature to achieve the same situation. During the soil reclamation process, the obtained residue as a soil amendment can not only provide a carbon source and mineral nutrients but can also improve the abundance and diversity of microbial communities. Thus, it facilitates the plant germination and the secondary removal of petroleum hydrocarbons. The integrated strategy of BCP of OS and residue utilization for soil reclamation is a promising management strategy, which is expected to realize the coordinated and benign disposal of more than one waste.


Assuntos
Petróleo , Solo , Solo/química , Esgotos/química , Pirólise , Carvão Vegetal , Óleos , Hidrocarbonetos
3.
Environ Sci Technol ; 57(27): 10117-10126, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37364020

RESUMO

Electrocatalytic reduction of nitrate to NH3 (NO3RR) on Cu offers sustainable NH3 production and nitrogen recycling from nitrate-contaminated water. However, Cu affords limited NO3RR activity owing to its unfavorable electronic state and the slow proton transfer on its surface, especially in neutral/alkaline media. Furthermore, although a synchronous "NO3RR and NH3 collection" system has been developed for nitrogen recycling from nitrate-laden water, no system is designed for natural water that generally contains low-concentration nitrate. Herein, we demonstrate that depositing Cu nanoparticles on a TiO2 support enables the formation of electron-deficient Cuδ+ species (0 < δ ≤ 2), which are more active than Cu0 in NO3RR. Furthermore, TiO2-Cu coupling induces local electric-field enhancement that intensifies water adsorption/dissociation at the interface, accelerating proton transfer for NO3RR on Cu. With the dual enhancements, TiO2-Cu delivers an NH3-N selectivity of 90.5%, mass activity of 41.4 mg-N h gCu-1, specific activity of 377.8 mg-N h-1 m-2, and minimal Cu leaching (<25.4 µg L-1) when treating 22.5 mg L-1 of NO3--N at -0.40 V, outperforming most of the reported Cu-based catalysts. A sequential NO3RR and NH3 collection system based on TiO2-Cu was then proposed, which could recycle nitrogen from nitrate-contaminated water under a wide concentration window of 22.5-112.5 mg L-1 at a rate of 209-630 mgN m-2 h-1. We also demonstrated this system could collect 83.9% of nitrogen from NO3--N (19.3 mg L-1) in natural lake water.


Assuntos
Nanopartículas , Nitratos , Nitratos/química , Prótons , Cobre , Nitrogênio , Água
4.
Environ Res ; 218: 115034, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502900

RESUMO

Using an indoor air purifier is an important solution for improving indoor air quality and protecting people from the harmful effects of air pollution on their health. The filter air purifiers can remove particulate matter including bioaerosols, but their filter media can cause secondary pollution. To fulfill this need, a new filterless indoor air purifier, the Cloud-Air-Purifying (CAP) air purifier, is presented in this study. Using heterogeneous condensation and supergravity technology, the CAP air purifier grows and collects fine particles, while rapidly disinfecting bioaerosols with chemical disinfection and ultraviolet (UV) disinfection. Furthermore, the purifying performance of the CAP air purifier was tested in a simulated cabin. The results showed the clean air delivery rate (CADR) of the CAP air purifier was approximately 150 m3/h, and the effective coefficient was 0.93. The CAP air purifier was highly efficient in purifying fine particulate matter, 93% for PM10 and 91% for particle size of 0.5-1 µm in 60 min, which was 13-58 times more than natural decay. The reason for the efficient removal of fine particles is that they can condense and grow in water vapor supersaturated environment and be collected in a supergravity field. Moreover, the CAP air purifier has significant bactericidal effects on bioaerosols. It achieved a disinfection efficiency of 99.99997% by decreasing bioaerosols from 108 CFU/m3 to less than 30 CFU/m3 in only 20 min when particle purification in combination with UV disinfection and disinfectant (ClO2). Furthermore, ClO2 release concentrations, noise, and power consumption were investigated for application purposes, with results showing that they were within acceptable limits. The study presents an innovative idea and design for preventing airborne microorganisms and particulate matter through heterogeneous condensation technology.


Assuntos
Filtros de Ar , Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Humanos , Material Particulado/análise , Tamanho da Partícula , Poluição do Ar em Ambientes Fechados/prevenção & controle , Poluição do Ar em Ambientes Fechados/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos
5.
J Environ Manage ; 348: 119171, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832287

RESUMO

Membrane fouling caused by inorganic ions and natural organic matters (NOMs) has been a severe issue in membrane distillation. Microbubble aeration (MB) is a promising technology to control membrane fouling. In this study, MB aeration was introduced to alleviate humic acid (HA) composited fouling during the treatment of simulative reverse osmosis concentrate (ROC) by vacuum membrane distillation (VMD). The objective of this work was to explore the HA fouling inhibiting effect by MB aeration and discuss its mechanism from the interfacial point of view. The results showed that VMD was effective for treating ROC, followed by a severe membrane fouling aggravated with the addition of 100 mg/L HA in feed solution, resulting in 45.7% decline of membrane flux. Analysis using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and zeta potential distribution of charged particles proved the coexistence of HA and inorganic cations (especially Ca2+), resulting in more serious membrane fouling. The introduction of MB aeration exhibited excellent alleviating effect on HA-inorganic salt fouling, with the normalized flux increased from 19.7% to 37.0%. The interfacial properties of MBs played an important role, which altered the zeta potential distributions of charged particles in HA solution, indicating that MBs adhere the HA complexations. Furthermore, this mitigating effect was limited at high inorganic cations concentration. Overall, MBs could change the potential characteristics of HA complexes, which also be used for other similar membrane fouling alleviation.


Assuntos
Substâncias Húmicas , Purificação da Água , Substâncias Húmicas/análise , Destilação/métodos , Microbolhas , Membranas Artificiais , Purificação da Água/métodos , Cátions
6.
BMC Med Res Methodol ; 22(1): 275, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266618

RESUMO

BACKGROUND: Currently, the direct method is the main approach for establishment of reference interval (RI). However, only a handful of studies have described the effects of sample size on establishment of RI and estimation of sample size. We describe a novel approach for estimation of the sample size when establishing RIs using the transformed parametric and non-parametric methods. METHODS: A total of 3,697 healthy participants were enrolled in this study. We adopted a two-layer nested loop sample size estimation method to determine the effects of sample size on RI, using thyroid-related hormone as an example. The sample size was selected as the calculation result when the width of the confidence interval (CI) of the upper and lower limit of the RI were both stably < 0.2 times the width of RI. Then, we calculated the sample size for establishing RIs via transformed parametric and non-parametric methods for thyroid-related hormones. RESULTS: Sample sizes for thyroid stimulating hormone (TSH), as required by parametric and non-parametric methods to establish RIs were 239 and 850, respectively. Sample sizes required by the transformed parametric method for free triiodothyronine (FT3), free thyroxine (FT4), total triiodothyronine (TT3) and total thyroxine (TT4) were all less than 120, while those required by the non-parametric method were more than 120. CONCLUSION: We describe a novel approach for estimating sample sizes for establishment of RI. A corresponding open-source code has been developed and is available for applications. The established method is suitable for most analytes, with evidence based on thyroid-related hormones indicating that different sample sizes are required to establish RIs using different methods for analytes with different variations.


Assuntos
Tiroxina , Tri-Iodotironina , Humanos , Tamanho da Amostra , Valores de Referência , Tireotropina , Mineração de Dados
7.
Environ Res ; 204(Pt B): 112088, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34563527

RESUMO

The diversity and stability of critical microbial communities are of great importance for ensuring soil fertility. From the perspective of stimulating microbial diversity in organic-matter-impoverished arable soils, soil conditioner with a certain proportion of labile organic carbon was prepared by short-time hydrothermal fermentation (SHF). The effects of applying SHF, along with soil conditioner derived from traditional aerobic fermentation (TF) and heterogeneous fertilizer (HF), on soil texture, dissolved organic matter evolution, the structure of humic acid, and the succession of dominant microbial taxa were evaluated. SHF enhanced the storage capacity of soil organic carbon and nitrogen retention, and increased the relative abundance of Proteobacteria, Firmicutes and Nitrospirae in organic-matter-impoverished arable soil, with Lysobacter as its significant difference species. In conclusion, the proposed soil conditioner and the positive effects observed in this study indicate that it could be used to solve dual problems of food waste recycling and arable soil improvement.


Assuntos
Eliminação de Resíduos , Solo , Carbono , Matéria Orgânica Dissolvida , Fermentação , Alimentos , Microbiologia do Solo
8.
Environ Res ; 215(Pt 2): 114375, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36167111

RESUMO

The residual antibiotics detected frequently in aquatic environment may pose a potential threat to human health and ecosystem. Exploring a possible way to remove them from antibiotic polluted-water is a key problem demanding prompt solution. To investigate their adsorption characteristics, three antibiotics including tetracycline (TC), ciprofloxacin (CIP), and sulfadiazine (SDZ) have been removed using sucrose-based mesoporous carbon (SMC) in single and co-existing systems. Characterization revealed that the SMC had a high Brunauer-Emmett-Teller (BET) surface area (1215.48 m2/g), large mesoporous pore size (6.36 nm), and abundant oxygen-containing functional groups, which might offer sufficient adsorption sites for antibiotics. The process of antibiotics adsorption was described well using pseudo-second-order model. The rate constant K2 at various temperatures followed the order 308 K > 298 K > 288 K. This finding suggesting the increase in temperature could promote the removal of antibiotics. The maximum adsorption capacities for TC (232.10 mg/g), CIP (257.30 mg/g), and SDZ (204.28 mg/g) of SMC were obtained using Langmuir isotherm (pH = 4-6, T = 308K, SMC dosage = 10 mg, C0 = 30-40 mg/L). These data implied SMC had the excellent adsorptive property and affinity to antibiotics. In binary systems, SMC offers efficient removal percentages (>90%) for each of the target antibiotic. While the removal efficiencies of TC, CIP, and SDZ by SMC in the ternary system were 90.40, 72.99, and 80.46%, respectively. These results suggested the competition on active sites of SMC happened among the three antibiotics. The affinities of SMC to three antibiotics followed the order TC > SDZ > CIP. The removal of antibiotics by SMC were mainly attributed to the mechanisms including electrostatic interactions, hydrophobic interactions, hydrogen bonding and so on. This study will provide a technical support for antibiotic wastewater treatment.


Assuntos
Antibacterianos , Carbono , Poluentes Químicos da Água , Purificação da Água , Adsorção , Antibacterianos/química , Carbono/química , Ciprofloxacina/química , Ecossistema , Humanos , Concentração de Íons de Hidrogênio , Cinética , Oxigênio , Sacarose , Sulfadiazina , Tetraciclina , Poluentes Químicos da Água/química , Purificação da Água/métodos
9.
Environ Sci Technol ; 55(23): 16163-16174, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34793160

RESUMO

Peroxymonosulfate (PMS)-based advanced oxidation processes (PMS-AOPs) as an efficient strategy for organic degradation are highly dependent on catalyst design and structured active sites. However, the identification of the active sites and their relationship with reaction mechanisms for organic degradation are not fully understood for a composite catalyst due to the complex structure. Herein, we developed a family of Co encapsulated in N-doped carbons (Co-PCN) with tailored types and contents of active sites via manipulated pyrolysis for PMS activation and ciprofloxacin (CIP) degradation, focusing on the correlation of active sites to generated reactive species and degradation routes of organics. The structure-function relationships between the different active sites in Co-PCN catalysts and reactive oxygen species (ROS), as well as bond breaking position of CIP, were revealed through regression analysis and density functional theory calculation. Co-Nx, O-C═O, C═O, graphitic N, and defects in Co-PCN stimulate the generation of 1O2 for oxidizing the C-C bond in the piperazine ring of CIP into C═O. The substitution of F by OH and hydroxylation of the piperazine ring might be induced by SO4•- and •OH, whose formation was affected by C-O, Co(0), Co-Nx, graphitic N, and defects. The findings provided new insights into reaction mechanisms in PMS-AOP systems and rational design of catalysts for ROS-oriented degradation of pollutants.


Assuntos
Carbono , Peróxidos , Domínio Catalítico , Ciprofloxacina
10.
J Clin Lab Anal ; 35(12): e24068, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34699640

RESUMO

AIM: To measure and evaluate the distribution and possible contributing factors of seven bone metabolism-associated biomarkers in Tibet, a plateau province of China. METHODS: A total of 1615 individuals were recruited from Tibet at three different altitudes. The levels and possible contributing factors of serum calcium, serum phosphorus, ALP, 25OHD, PINP, CTX, and PTH were evaluated. RESULTS: In total, 1246 Tibetan adults (males: n = 543) were eventually enrolled in this study. Multiple linear regression recognized age, sex, altitude, and BMI as the major effect factors. The levels of ALP, PINP, and CTX in males continuously decreased with age; however, those in females increased after approximately 39 years of age. Males had higher 25OHD levels (23.9 vs. 15.4 ng/ml) but lower levels of serum phosphorus (1.12 vs. 1.19 mmol/L) and PTH (41.3 vs. 47.4 pg/ml) than females. Before the age of 50, males had higher levels of calcium, ALP, PINP, and CTX than females, and the opposite trend was observed after the age of 50. The highest levels of serum calcium and phosphorus and the lowest levels of PINP and CTX were found in the Shigatse/Lhasa region, suggesting a better bone metabolism status. Compared with reports from plain areas of China, significantly higher levels of PINP (65.3 vs. 49.36 ng/ml) and CTX (0.46 vs. 0.37 ng/ml) were recorded in Tibetan adults. CONCLUSION: A more active bone turnover status was found in Tibetan adults than in individuals from the plain areas of China.


Assuntos
Biomarcadores/sangue , Osso e Ossos/metabolismo , Adulto , Envelhecimento/fisiologia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Altitude , Biomarcadores/metabolismo , Remodelação Óssea/fisiologia , Cálcio/sangue , Cálcio/urina , China , Colágeno Tipo I/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Tibet , Triglicerídeos/sangue
11.
Clin Chem Lab Med ; 59(1): 139-145, 2020 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-32653871

RESUMO

Objectives: Drug-laboratory test interactions (DLTIs) are one of the major sources of laboratory errors. Calcium dobesilate (CaD) interference on serum creatinine testing is a widespread problem that has long been ignored in China. A national EQA-based survey was launched to investigate the current status of CaD interference on creatinine routine methods used in China and enhance the education of CaD interference in clinical laboratories. Methods: A descriptive survey was developed to characterize the status quo of Chinese laboratory professionals' cognition to CaD interference. Four of survey samples which were spiked with/without interference additive were shipped to 175 participant laboratories. The target reference values from a reference measurement procedure were compared against the results from participating laboratories to evaluate the CaD interference on serum creatinine measurements using enzymatic method or Jaffé method. Results: The lack of knowledge of DLTIs and the barriers to collect information from pharmacological and laboratory data systems had become the main problems on implementing DLTIs education in China. A significant negative influence of CaD on enzymatic method was observed regardless of measurement platforms. Jaffé method was generally free from interaction with CaD but showed poor precision and accuracy at low creatinine concentrations. Conclusions: More efforts should be made to enhance the education of DLTIs in clinical laboratories in China.


Assuntos
Dobesilato de Cálcio/sangue , Química Clínica/educação , Creatinina/sangue , Testes Diagnósticos de Rotina , Inquéritos e Questionários , China , Humanos , Pessoal de Laboratório Médico
12.
J Clin Lab Anal ; 34(8): e23342, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32320096

RESUMO

BACKGROUND: Soluble transferrin receptor (sTfR) is a promising indicator of iron deficiency anemia (IDA). Here, we investigated the application value of sTfR assays based on three different methods for the diagnosis of IDA. METHODS: The sTfR concentrations in two groups of patient specimens with high-level and low-level sTfR concentrations and in quality control materials were measured four times a day for five consecutive days to evaluate the precision of the three methods. We selected patients with IDA, anemia of chronic disease (ACD), or chronic diseases with iron deficiency anemia (CIDA), and apparently healthy subjects, and measured the serum sTfR concentrations in all subjects using the three different methods. The cutoff points for an IDA diagnosis using the three assays and their corresponding clinical sensitivities and specificities were calculated by receiver operating characteristic analysis. RESULTS: For the diagnosis of IDA, the cutoff points of sTfR measured by the chemiluminescent, immunoturbidimetric, and immunonephelometric assays were 2.91, 6.70, and 2.48 mg/L, respectively. The corresponding sensitivities were 85.59%, 85.59%, and 85.59%, the specificities were 91.47%, 90.31%, and 90.70%, and area under the curve was 0.943, 0.944, and 0.936, respectively. The sTfR concentrations measured by the different methods were significantly higher in the IDA and CIDA groups than in the other two groups (P < .05). CONCLUSIONS: The sTfR based on the three different measurement methods presented promising analytical performances and met the clinical requirements for sensitivity and specificity. However, the different measurement methods had markedly different cutoff points for IDA diagnosis, which should be critically considered in clinical practice.


Assuntos
Anemia Ferropriva/diagnóstico , Receptores da Transferrina/sangue , Adulto , Idoso , Anemia Ferropriva/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Bull Environ Contam Toxicol ; 105(3): 358-365, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32740748

RESUMO

Sulfamethoxazole (SMZ) is a kind of sulfonamides antibiotic, which is widely used in human life. This study investigated the effects of SMZ on physiological and biochemical indexes of Chlorella vulgaris (C. vulgaris) and Microcystis aeruginosa (M. aeruginosa) for 35-day. The results showed that SMZ inhibited the growth and Chl-a content of C. vulgaris and M. aeruginosa, and growth inhibition rate was 8.06%-95.86%, Chl-a content decreased 2.44%-98.04%. SMZ resulting in increased SOD and CAT activity and destroyed the dynamic balance of antioxidant system. In addition, SMZ increased the content of malondialdehyde (MDA) in algae, destroyed the cell membrane to a certain extent, which was 1.8-7.3 folds higher than the control group. High concentration of SMZ can make algae cells exceed the limit of cell antioxidant capacity. Coupled with the serious damage of cell membrane, algae cells begin to appear a large number of death phenomenon.


Assuntos
Antibacterianos/toxicidade , Chlorella vulgaris/fisiologia , Microcystis/fisiologia , Sulfametoxazol/toxicidade , Antioxidantes/metabolismo , Chlorella vulgaris/efeitos dos fármacos , Malondialdeído/metabolismo , Microcystis/efeitos dos fármacos , Sulfametoxazol/metabolismo
14.
J Environ Sci (China) ; 97: 25-34, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933737

RESUMO

Shijiazhuang, the city with the worst air quality in China, is suffering from severe ozone pollution in summer. As the key precursors of ozone generation, it is necessary to control the Volatile Organic Compounds (VOCs) pollution. To have a better understanding of the pollution status and source contribution, the concentrations of 117 ambient VOCs were analyzed from April to August 2018 in an urban site in Shijiazhuang. Results showed that the monthly average concentration of total VOCs was 66.27 ppbv, in which, the oxygenated VOCs (37.89%), alkanes (33.89%), and halogenated hydrocarbons (13.31%) were the main composite on. Eight major sources were identified using Positive Matrix Factorization modeling with an accurate VOCs emission inventory as inter-complementary methods revealed that the petrochemical industry (26.24%), other industrial sources (15.19%), and traffic source (12.24%) were the major sources for ambient VOCs in Shijiazhuang. The spatial distributions of major industrial activities emissions were identified by using geographic information statistics system, which illustrated the VOCs was mainly from the north and southeast of Shijiazhuang. The inverse trajectory analysis using Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) and Potential Source Contribution Function (PSCF) clearly demonstrated the features of pollutant transport to Shijiazhuang. These findings can provide references for local governments regarding control strategies to reduce VOCs emissions.


Assuntos
Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , China , Cidades , Monitoramento Ambiental , Emissões de Veículos/análise
15.
J Clin Lab Anal ; 33(1): e22628, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30043502

RESUMO

BACKGROUND: Lp-PLA2 is a novel inflammation marker in cardiovascular disease. While several manufactures have registered Lp-PLA2 activity reagents, few studies have investigated the consistency among these assays. In this study, we compared and recalibrated Lp-PLA2 activity assays. METHODS: Serum samples from 110 patients and 140 healthy individuals were collected for method comparison and reference interval validation, respectively. Fresh human serum pools (847 and 442 U/L) were used for recalibration. Lp-PLA2 activity was analyzed using all five assays with a Beckman AU 5800 analyzer. Passing-Bablok regression equations and Bland-Altman plots were used to estimate the relationship and bias among the results. A 2.5% confidence interval (CI) and 97.5% CI were used to establish a laboratory reference interval. RESULTS: Assay imprecision varied from 0.8%-2.9%, while the overall coincidence rates ranged from 75.5%-98.2%. Passing-Bablok regression shows excellent linear correlation between Evermed and Diasys (R2  = 0.999), while that between Diazyme and Evermed was poor (R2  = 0.846). The R2 and correlation coefficient r among assays were 0.846-0.999 and 0.8947-0.9993, respectively. The mean bias percentages ranged from -71.5%-1.6% and -2.0%-11.6% before and after recalibration. As Diazyme and Diasys were not comparable, the Diazyme assay was not recalibrated. The reference intervals determined for Diasys, Evermed, Hengxiao, and Zybio were 184-605, 208-704, 81-328, and 273-696 U/L, respectively. CONCLUSIONS: Our results indicate that recalibration increased assay agreement and also highlight the need for each laboratory to establish its own reference interval for Lp-PLA2 activity.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase , Análise Química do Sangue , Ensaios Enzimáticos , 1-Alquil-2-acetilglicerofosfocolina Esterase/sangue , 1-Alquil-2-acetilglicerofosfocolina Esterase/metabolismo , Adulto , Idoso , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Calibragem , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/enzimologia , Estudos de Casos e Controles , China , Ensaios Enzimáticos/métodos , Ensaios Enzimáticos/normas , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Reprodutibilidade dos Testes
16.
J Environ Sci (China) ; 78: 183-192, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30665637

RESUMO

The lack of fresh water in the world makes the search for an effective method to decontaminate water an urgent priority. An important step is to remove different multivalent ions in salt treatment. Nanofiltration (NF) has been used for treating water containing different kinds of salts. In this work, sulfonate group-modified graphene oxide (SGO) was prepared, and added during the interfacial polymerization (IP) reaction to prepare SGO-modifiedNF membranes (PA-SGO). The chemical composition, structure and surface properties of PA and PA-SGO membranes were characterized by FT-IR, XPS, SEM, AFM, contact angle and zeta potential measurements. Their water flux, salt rejection and anti-fouling abilities were investigated systematically. The testing results showed that the water flux of PA-SGO (0.03% SGO) was 45.85 LMH under a pressure of 0.2 MPa, and the salt rejection varied in the order of Na2SO4 (98.99%) > MgSO4 (91.25%) > MgCl2 (42.27%) > NaCl (21.96%). An anti-fouling experiment indicated that the PA-SGO membrane had good anti-fouling properties because of its decreased roughness and increased hydrophilicity and electronegativity. The PA-SGO membrane has good potential for use in removing salt ions from water.


Assuntos
Filtração/métodos , Grafite/química , Cloreto de Sódio/química , Purificação da Água/métodos , Membranas Artificiais , Óxidos/química , Polimerização , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfonas/química , Propriedades de Superfície , Poluentes Químicos da Água
17.
Environ Sci Technol ; 52(7): 4457-4463, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29513525

RESUMO

Zwitterions of charge-balanced units have super-low fouling properties induced by ionic solvation, but their extensive applications in polymeric substrates are strictly constrained by current constructing strategies. A zwitterion-like, charge-balanced ultrathin layer with high antifouling capacity was covalently constructed on delicate aromatic polyamide (PA) reverse osmosis (RO) membranes via a mild and solvent-free grafting-to strategy. Two oppositely charged commercial short-chain carbonyl alkenes, 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and methacryloxyethyltrimethylammonium chloride (DMC), were directly mixed-grafted with amino groups on PA RO membrane surface via Michael addition. Under ambient temperature and pressure, these oppositely charged compounds were assembled into a zwitterion-like, charge-balanced ultrathin layer. The dynamic fouling experiments indicated that the modified membrane exhibited strong antifouling properties and excellent permeation recovery abilities. Surface characterization revealed that the selective layer thickness and surface roughness were not measurably changed. More meaningful is that the typical ridge-and-valley surface structure and the excellent separation performance were both well preserved after modification. This opens a universal avenue to construct a zwitterion-like, ultrathin antifouling layer on the delicate polymer substrate without compromising its original matrix structure and performance, which has promising application in areas of biosensors, tissue engineering, and biomaterials.


Assuntos
Membranas Artificiais , Polímeros , Filtração
18.
Clin Chem Lab Med ; 56(7): 1152-1160, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29729137

RESUMO

BACKGROUND: Measuring sex hormones is essential in diagnosing health issues such as testicular dysfunction, male infertility and feminization syndrome. However, there are no reports on reference intervals (RIs) in Chinese men. We conducted a nationwide multicenter study to establish RIs for seven sex hormones (luteinizing hormone [LH], follicle-stimulating hormone [FSH], prolactin [PRL], total testosterone [TT], free testosterone [FT], bioavailable testosterone [BAT] and estrogen [E2]), as well as sex hormone-binding globulin (SHBG). METHODS: In 2013, 1043 apparently healthy adult men from five representative cities in China (Beijing, Hangzhou, Guangzhou, Dalian and Urumqi) were recruited; hormones were measured using an automated immunoassay analyzer. Multiple regression analysis (MRA) was performed to identify sources of variation (SVs) that might influence the hormone serum levels. RIs were computed using the parametric method. RESULTS: Dalian and Hangzhou had significantly higher E2 values than other cities; age was a major source of variation for FSH, LH, PRL, SHBG, FT and BAT. FSH, LH and SHBG increased significantly with age, while PRL, FT and BAT decreased with age. TT showed no significant age-related changes. Median (RIs) derived without partition by age were as follows: FSH, 5.6 (1.9-16.3) IU/L; LH, 4.2 (1.6-10.0) IU/L; PRL, 189 (88-450) mIU/L; E2, 85 (4.7-195) pmol/L; SHBG, 29.4 (11.5-66.3) nmol/L; TT, 15.6 (7.4-24.5) nmol/L; FT, 0.31 (0.16-0.52) nmol/L; and BAT, 8.0 (3.7-13.2) nmol/L. RIs were also derived in accordance with between-city and between-age differences. CONCLUSIONS: RIs were established for sex hormones and SHBG in apparently healthy Chinese men in consideration of age.


Assuntos
Estrogênios/normas , Hormônio Foliculoestimulante/normas , Hormônio Luteinizante/normas , Prolactina/normas , Globulina de Ligação a Hormônio Sexual/normas , Testosterona/normas , Adulto , Índice de Massa Corporal , China , Estrogênios/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Prolactina/sangue , Valores de Referência , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2212-6, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26672296

RESUMO

Using three-dimensional fluorescence technology, we studied fluorescent characteristics of two polluted rivers by a surface flow+vertical flow combined constructed wetlands of dissolving organic matter. The results showed that (1) the main sources of water-soluble humic organic matter in constructed wetland was biological metabolic input instead of terrigenous input; (2) in the later section of the surface flow constructed wetland, part of proteinoid substance changed into fulvic acid-like substance, which showed that the composition of dissolved organic matter and material structure tended to be stable after surface flow combined constructed wetland treatment; (3) it was of great significance that surface flow constructed wetland in structure transformation of water soluble organic matter, which could significantly improve the stability of water soluble organic matter. Surface flow+vertical flow combined constructed wetland process of dissolved organic matter had a good removal effect.


Assuntos
Monitoramento Ambiental , Compostos Orgânicos/análise , Áreas Alagadas , Espectrometria de Fluorescência
20.
Water Res ; 253: 121358, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38402750

RESUMO

Membrane biofouling is a challenge to be solved for the stable operation of the seawater reverse osmosis (SWRO) membrane. This study explored the regulation mechanism of quorum sensing (QS) inhibition on microbial community composition and population-level behaviors in seawater desalination membrane biofouling. A novel antibiofouling SWRO membrane (MA_m) by incorporating one of quorum sensing inhibitors (QSIs), methyl anthranilate (MA) was prepared. It exhibited enhanced anti-biofouling performance than the exogenous addition of QSIs, showing long-term stability and alleviating 22 % decrease in membrane flux compared with the virgin membrane. The results observed that dominant bacteria Epsilon- and Gamma-proteobacteria (Shewanella, Olleya, Colwellia, and Arcobacter), which are significantly related to (P ≤ 0.01) the metabolic products (i.e., polysaccharides, proteins and eDNA), are reduced by over 80 % on the MA_m membrane. Additionally, the introduction of MA has a more significant impact on the QS signal-sensing pathway through binding to the active site of the transmembrane sensor receptor. It effectively reduces the abundance of genes encoding QS and extracellular polymeric substance (EPS) (exopolysaccharides (i.e., galE and nagB) and amino acids (i.e., ilvE, metH, phhA, and serB)) by up to 50 % and 30 %, respectively, resulting in a reduction of EPS by more than 50 %, thereby limiting the biofilm formation on the QSI-modified membrane. This study provides novel insights into the potential of QSIs to control consortial biofilm formation in practical SWRO applications.


Assuntos
Incrustação Biológica , Microbiota , Purificação da Água , Percepção de Quorum , Biofilmes , Matriz Extracelular de Substâncias Poliméricas , Osmose , Água do Mar/microbiologia , Membranas Artificiais , Purificação da Água/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA