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3.
Front Hum Neurosci ; 17: 1008490, 2023.
Article in English | MEDLINE | ID: mdl-37405324

ABSTRACT

Background: Brain oscillations facilitate interaction within the brain network and between the brain and heart activities, and the alpha wave, as a prominent brain oscillation, plays a major role in these coherent activities. We hypothesize that mindfully breathing can make the brain and heart activities more coherent in terms of increased connectivity between the electroencephalogram (EEG) and electrocardiogram (ECG) signals. Methods: Eleven participants (28-52 years) attended 8 weeks of Mindfulness Based Stress Reduction (MBSR) training. EEG and ECG data of two states of mindful breathing and rest, both eye-closed, were recorded before and after the training. EEGLAB was used to analyze the alpha band (8-12 Hz) power, alpha peak frequency (APF), peak power and coherence. FMRIB toolbox was used to extract the ECG data. Heart coherence (HC) and heartbeat evoked potential (HEP) were calculated for further correlation analysis. Results: After 8 weeks of MBSR training, the correlation between APF and HC increased significantly in the middle frontal region and bilateral temporal regions. The correlation between alpha coherence and heart coherence had similar changes, while alpha peak power did not reflect such changes. In contrast, spectrum analysis alone did not show difference before and after MBSR training. Conclusion: The brain works in rhythmic oscillation, and this rhythmic connection becomes more coherent with cardiac activity after 8 weeks of MBSR training. Individual APF is relatively stable and its interplay with cardiac activity may be a more sensitive index than power spectrum by monitoring the brain-heart connection. This preliminary study has important implications for the neuroscientific measurement of meditative practice.

4.
Article in English | MEDLINE | ID: mdl-36981692

ABSTRACT

In this study, we assessed the general marine environmental knowledge and attitudes of university students from eight public universities in Hong Kong. The Ocean Literacy Framework and revised New Ecological Paradigm (NEP) were used as tools for questionnaire development. Data were collected via in-person and online surveys. An in-person survey was conducted at the university canteen from 16 May to 24 May 2017, and an online survey was conducted via email from 1 May to 31 May 2017. A structured questionnaire was provided to interested students from different levels of study and majors. Data obtained from these surveys were summarized based on participants' correct answers in the general knowledge section and five-point Likert scaling for attitude statements. Results show that Hong Kong university students possess moderate marine environmental knowledge and pro-environmental attitudes. Knowledge scores significantly correlate with demographic variables, such as major of study, gender, institution, and parents' education. Students' pro-environmental attitudes are associated with different factors, including participation in various marine recreational activities, taking marine-related courses, and attachment to conservative marine initiatives. The study results have implications regarding the advancement of marine environmental knowledge and the pro-environmental attitudes of university students, such as mapping a well-structured pathway for disseminating marine environmental knowledge, curricular involvement, and the development of an integrated web resource.


Subject(s)
Attitude , Literacy , Humans , Hong Kong , Universities , Students , Surveys and Questionnaires , Oceans and Seas , Health Knowledge, Attitudes, Practice
5.
Ecotoxicology ; 31(7): 1111-1119, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35841472

ABSTRACT

The concentrations, distribution, and ecological risks of 24 typical antibiotics in Hong Kong rivers and seawater were investigated using high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UHPLC-EI-MS/MS). The results showed that the select antibiotics were widely distributed in the study area. Among the target antibiotics, the detection rate of tetracyclines (TCs) was 100%, which indicated the widespread use of TCs in Hong Kong. The detection rates of sulfonamides (SAs) (57.1-100%), fluoroquinolones (FQs) (78.6-100%), roxithromycin (RTM) (50%) and novobiocin (NOV) (50%) were all above 50%. Compared with river water (7.9-114.26 ng/L, medium: 27.7 ng/L), concentrations of the most antibiotics in seawater (9.5-32.0 ng/L, medium: 13.3 ng/L) were lower; seawater concentrations were similar to those reported from other coastal cities, such as Guangzhou and Zhuhai in China, which implied that the source of marine antibiotic pollution may be the nearby rivers, and the vastness of the ocean causes environmental dilution of antibiotics. According to the ratio of the measured environmental concentration (MEC) to the predicted no-effect concentration (PNEC), ofloxacin (OFX) (average risk quotient: 1.94E-01) and ciprofloxacin (CFX) (average risk quotient: 3.53E-01) posed medium to high ecological risk in most places, whereas other antibiotics posed lower risk. In Yuen Long, where there were many livestock farms nearby, the detected concentration of antibiotics was higher, indicating that livestock wastewater may be the major reason for the increase in antibiotic levels in this area. In general, the detected concentration of antibiotics in Hong Kong was lower than that in the United States, Japan, the United Kingdom, and coastal areas of China, but the long-term existence of low concentrations of antibiotics also poses great risks. According to the risk assessment, Hong Kong should pay more attention to the use of FQs (e.g., OFX and CFX) in the future.


Subject(s)
Anti-Bacterial Agents , Water Pollutants, Chemical , Anti-Bacterial Agents/analysis , China , Environmental Monitoring/methods , Fluoroquinolones/analysis , Risk Assessment , Rivers/chemistry , Tandem Mass Spectrometry , Water/analysis , Water Pollutants, Chemical/analysis
6.
Environ Toxicol Chem ; 41(10): 2613-2621, 2022 10.
Article in English | MEDLINE | ID: mdl-35899985

ABSTRACT

Increased disinfection efforts in various parts of China, including Hong Kong, to prevent the spread of the novel coronavirus may lead to elevated concentrations of disinfectants in domestic sewage and surface runoff in Hong Kong, generating large quantities of toxic disinfection byproducts. Our study investigated the presence and distribution of four trihalomethanes (THMs), six haloacetic acids (HAAs), and eight nitrosamines (NAMs) in rivers and seawater in Hong Kong. The concentrations of THMs (mean concentration: 1.6 µg/L [seawater], 3.0 µg/L [river water]), HAAs (mean concentration: 1.4 µg/L [seawater], 1.9 µg/L [river water]), and NAMs (mean concentration: 4.4 ng/L [seawater], 5.6 ng/L [river water]) did not significantly differ between river water and seawater. The total disinfection byproduct content in river water in Hong Kong was similar to that in Wuhan and Beijing (People's Republic of China), and the total THM concentration in seawater was significantly higher than that before the COVID-19 pandemic. Among the regulated disinfection byproducts, none of the surface water samples exceeded the maximum index values for THM4 (80 µg/L), HAA5 (60 µg/L), and nitrosodimethylamine (100 ng/L) in drinking water. Among the disinfection byproducts detected, bromoform in rivers and seawater poses the highest risk to aquatic organisms, which warrants attention and mitigation efforts. Environ Toxicol Chem 2022;41:2613-2621. © 2022 SETAC.


Subject(s)
COVID-19 , Disinfectants , Drinking Water , Water Pollutants, Chemical , Water Purification , Dimethylnitrosamine , Disinfectants/analysis , Disinfection , Halogenation , Hong Kong , Humans , Pandemics , Pilot Projects , Sewage , Trihalomethanes/analysis , Water Pollutants, Chemical/analysis
7.
IEEE Trans Cybern ; 52(6): 5559-5572, 2022 Jun.
Article in English | MEDLINE | ID: mdl-33400663

ABSTRACT

Attribute reduction is one of the most important preprocessing steps in machine learning and data mining. As a key step of attribute reduction, attribute evaluation directly affects classification performance, search time, and stopping criterion. The existing evaluation functions are greatly dependent on the relationship between objects, which makes its computational time and space more costly. To solve this problem, we propose a novel separability-based evaluation function and reduction method by using the relationship between objects and decision categories directly. The degree of aggregation (DA) of intraclass objects and the degree of dispersion (DD) of between-class objects are first defined to measure the significance of an attribute subset. Then, the separability of attribute subsets is defined by DA and DD in fuzzy decision systems, and we design a sequentially forward selection based on the separability (SFSS) algorithm to select attributes. Furthermore, a postpruning strategy is introduced to prevent overfitting and determine a termination parameter. Finally, the SFSS algorithm is compared with some typical reduction algorithms using some public datasets from UCI and ELVIRA Biomedical repositories. The interpretability of SFSS is directly presented by the performance on MNIST handwritten digits. The experimental comparisons show that SFSS is fast and robust, which has higher classification accuracy and compression ratio, with extremely low computational time.


Subject(s)
Algorithms , Data Mining , Data Mining/methods , Machine Learning
8.
J Hazard Mater ; 421: 126709, 2022 01 05.
Article in English | MEDLINE | ID: mdl-34315021

ABSTRACT

Nanoscale zero-valent iron nanoparticles (nZVI) have been used for groundwater remediation and wastewater treatment due to their high reactivity, high adsorption capacity and nontoxicity. However, side reactions generally occur in tandem with the target contaminants removal process, resulting in poor electron selectivity (ES) of nZVI, and subsequently restricting its commercial application. Major efforts to increase ES of nZVI have been made in recent years. This review's objective is to provide a progress report on the significant developments in nZVI's ES during the past decade. Firstly, the definition of ES and its quantification approaches were documented, and the intrinsic (i.e. particle size, crystallinity, and surface area) and extrinsic factors (i.e. solutions pH, target contaminant concentration, and presence of co-contaminants) affecting the ES of nZVI were reported. The latest techniques for increasing ES were summarized in detail, with reference made to sulfidation, magnetization, carbon loading and other features. Then the mechanisms of those strategies for ES enhancement were described. Finally, some constructive suggestions on future research directions concerning nZVI's ES in the future were proposed.


Subject(s)
Environmental Restoration and Remediation , Groundwater , Water Pollutants, Chemical , Water Purification , Electrons , Iron , Water Pollutants, Chemical/analysis
9.
Sci Total Environ ; 807(Pt 2): 150826, 2022 Feb 10.
Article in English | MEDLINE | ID: mdl-34627922

ABSTRACT

Air-conditioning accounts for a vast amount of electricity consumption in Hong Kong, and household decarbonization of cooling is considered a vital means of reducing electricity use. However, little information is available on the determinants of household decarbonizing cooling behaviour, and emotional factors are often ignored in the pro-environmental behaviour literature. Thus, this study attempts to address this gap by applying an emotional extension of the theory of planned behaviour (TPB). A total of 295 valid responses were obtained using a questionnaire survey and tested via structural equation modeling (SEM). The incorporation of additional variables improves the explanatory power of the household decarbonizing cooling behaviour model, and the results reveal that subjective norms is the most influential factor, followed by affective connection to nature and negative anticipated emotions. Meanwhile, attitude towards the behaviour and perceived behavioural control are found to have a nonsignificant effect on behavioural intention. These findings not only highlight the importance of emotions in predicting electricity-saving behaviour, but also provide useful insights to formulate effective approaches for motivating citizens to engage in decarbonizing cooling behaviour at home.


Subject(s)
Air Conditioning , Attitude , Emotions , Intention , Air Pollution/prevention & control , Cities , Cold Temperature , Hong Kong , Humans , Motivation , Surveys and Questionnaires
10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 3791-3794, 2021 11.
Article in English | MEDLINE | ID: mdl-34892061

ABSTRACT

Brain electrical stimulation has shown the capability to modulate neural activities in a variety of ways. Compared with transcranial direct current stimulation(tDCS), transcranial alternating current stimulation (tACS) may affect brain activities differently through a frequency-based mechanism. This pilot study applied tACS to the scalp following the meridian (Jingluo) of traditional Chinese medicine to explore its potential neural modulation effect. A wearable electroencephalogram (EEG) device was used to measure the frontal activity in a female participant before and after tACS longitudinally. A combined method of singular spectrum analysis (SSA)-independent components analysis (ICA) was applied to separate potential artifacts from ocular and other irrelevant sources. The results demonstrated that SSA-ICA could effectively separate signals from different sources especially the ocular artifact. EEG spectrum analysis showed that short-term tACS could increase the power of delta waves. This study has good implications for the use of tACS and SSA-ICA method for the study of brain activities. Future research is needed to refine more optimum parameters of tACS and SSA-ICA to make the evidence more solid.Clinical Relevance- tACS may influence the brain wave oscillations through the frequency-based mechanism. SSA-ICA method helps to broaden the use of wearable EEG devices for various clinical applications.


Subject(s)
Meridians , Transcranial Direct Current Stimulation , Electroencephalography , Female , Humans , Pilot Projects , Scalp
11.
Microbiol Spectr ; 9(1): e0034221, 2021 09 03.
Article in English | MEDLINE | ID: mdl-34346748

ABSTRACT

As the COVID-19 pandemic progresses, there is an increasing need for rapid, accessible assays for SARS-CoV-2 detection. We present a clinical evaluation and real-world implementation of the INDICAID COVID-19 rapid antigen test (INDICAID rapid test). A multisite clinical evaluation of the INDICAID rapid test using prospectively collected nasal (bilateral anterior) swab samples from symptomatic subjects was performed. The INDICAID rapid test demonstrated a positive percent agreement (PPA) and negative percent agreement (NPA) of 85.3% (95% confidence interval [95% CI], 75.6% to 91.6%) and 94.9% (95% CI, 91.6% to 96.9%), respectively, compared to laboratory-based reverse transcriptase PCR (RT-PCR) using nasal specimens. The INDICAID rapid test was then implemented at COVID-19 outbreak screening centers in Hong Kong as part of a testing algorithm (termed "dual-track") to screen asymptomatic individuals for prioritization for confirmatory RT-PCR testing. In one approach, preliminary positive INDICAID rapid test results triggered expedited processing for laboratory-based RT-PCR, reducing the average time to confirmatory result from 10.85 h to 7.0 h. In a second approach, preliminary positive results triggered subsequent testing with an onsite rapid RT-PCR, reducing the average time to confirmatory result to 0.84 h. In 22,994 asymptomatic patients, the INDICAID rapid test demonstrated a PPA of 84.2% (95% CI, 69.6% to 92.6%) and an NPA of 99.9% (95% CI, 99.9% to 100%) compared to laboratory-based RT-PCR using combined nasal/oropharyngeal specimens. The INDICAID rapid test has excellent performance compared to laboratory-based RT-PCR testing and, when used in tandem with RT-PCR, reduces the time to confirmatory positive result. IMPORTANCE Laboratory-based RT-PCR, the current gold standard for COVID-19 testing, can require a turnaround time of 24 to 48 h from sample collection to result. The delayed time to result limits the effectiveness of centralized RT-PCR testing to reduce transmission and stem potential outbreaks. To address this, we conducted a thorough evaluation of the INDICAID COVID-19 rapid antigen test, a 20-minute rapid antigen test, in both symptomatic and asymptomatic populations. The INDICAID rapid test demonstrated high sensitivity and specificity with RT-PCR as the comparator method. A dual-track testing algorithm was also evaluated utilizing the INDICAID rapid test to screen for preliminary positive patients, whose samples were then prioritized for RT-PCR testing. The dual-track method demonstrated significant improvements in expediting the reporting of positive RT-PCR test results compared to standard RT-PCR testing without prioritization, offering an improved strategy for community testing and controlling SARS-CoV-2 outbreaks.


Subject(s)
Antigens, Viral/analysis , Asymptomatic Diseases , COVID-19 Testing/methods , COVID-19/diagnosis , COVID-19/immunology , SARS-CoV-2/isolation & purification , Adult , Clinical Laboratory Techniques/methods , False Negative Reactions , False Positive Reactions , Female , Hong Kong , Humans , Male , Mass Screening/methods , Middle Aged , Pandemics , Polymerase Chain Reaction , SARS-CoV-2/genetics , Sensitivity and Specificity , Specimen Handling , Time Factors , Young Adult
12.
Bioresour Technol ; 341: 125743, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34438283

ABSTRACT

Reducing the preparation cost of magnetic biochar is necessary for its large-scale application as an adsorbent. In this study, stainless steel pickling waste liquor and rice straw were successfully applied to synthesize of magnetic biochar (SPWL-MBC). Several iron oxides adhered on the biochar matrix, mainly Fe3O4, Fe2O3 and FeO. SPWL-MBC exhibited superparamagnetism, and its specific surface area was 274.29 m2/g. The material was able to adsorb a model contaminant, crystal violet (CV), with a maximum adsorption capacity of approximately 111.48 mg/g. Adsorption mechanism analysis showed that iron oxides, π-π interaction, hydrogen bonding and electrostatic interaction were responsible for the adsorption of CV. The CV adsorption efficiency of SPWL-MBC remained 71.91% after three adsorption-regeneration cycles. These outcomes illustrate that the magnetic biochar prepared from stainless steel pickling waste liquor can effectively remove CV from wastewater.


Subject(s)
Oryza , Water Pollutants, Chemical , Adsorption , Charcoal , Gentian Violet , Kinetics , Magnetic Phenomena , Stainless Steel
13.
Iberoam. j. med ; 3(3): 227-233, Agos. 2021. tab, graf
Article in English | IBECS | ID: ibc-231836

ABSTRACT

Introduction: The use of tele-rehabilitation devices to aid physiotherapy has gained popularity in recent years. In particular, measuring limb range of motion with a wearable mobile sensor can facilitate rehabilitation therapies by providing more efficient progress monitoring and reducing clinicians’ workload. This study aimed to examine the test-retest reliability and validity of using a wearable mobile sensor to measure upper limb range of motion (ROM).Materials and methods: Participants were recruited by convenient sampling. They were instructed to perform four kinds of upper limb movements including shoulder flexion, abduction, external rotation and elbow flexion, from which the ROM was measured by Mobile sensors REBEE (XCLR8 Technologies) and a standard goniometer (Model 12-1000) in each movement. Each kind of movements and the two ROM measurements were performed twice for the evaluation of test-retest reliability using Intraclass Correlation Coefficients (ICC). Pearson's correlations were computed between the ROM measured by the mobile sensors and the goniometer in each movement to assess construct validities of the mobile sensors. The agreement (95% mean difference) between the two sets of measurement was illustrated by Bland-Altman plots.Results: Thirty-four asymptomatic young Asian adults (15 males) participated in this study (Mage ± SD, 24.2 ± 3.82 years). The ICC for the ROM measured by the sensors were between 0.94 and 0.99, p <0.01 and for the goniometer measurements were between 0.95 and 0.98, p <0.01 in the four movements, indicating excellent reliability in both measurement methods. The Pearson's correlation between the sensor’s and goniometric ROM measurements in four kinds of movements ranged from r =0.96 to 0.99, p <0.01, indicating a very strong construct validity for using the mobile sensors to measure upper limb ROM. The mean difference between the two measurements ranged from 0.13 degrees to 7.6 degrees...(AU)


Introducción: El uso de dispositivos de tele-rehabilitación para ayudar a la fisioterapia ha ganado popularidad en los últimos años. En particular, medir el rango de movimiento de las extremidades con un sensor móvil portátil puede facilitar las terapias de rehabilitación al proporcionar una supervisión del progreso más eficiente y reducir la carga de trabajo de los médicos. Este estudio tuvo como objetivo examinar la confiabilidad y la validez test-retest del uso de un sensor móvil portátil para medir el rango de movimiento de las extremidades superiores (ROM).Materiales y métodos: Los participantes fueron reclutados mediante muestreo conveniente. Se les indicó que realizaran cuatro tipos de movimientos de las extremidades superiores, incluida la flexión del hombro, la abducción, la rotación externa y la flexión del codo, a partir de los cuales se midió el ROM con los sensores móviles REBEE (XCLR8 Technologies) y un goniómetro estándar (Modelo 12-1000) en cada movimiento. . Cada tipo de movimientos y las dos mediciones de ROM se realizaron dos veces para la evaluación de la confiabilidad test-retest utilizando coeficientes de correlación intraclase (ICC). Se calcularon las correlaciones de Pearson entre el ROM medido por los sensores móviles y el goniómetro en cada movimiento para evaluar la validez de constructo de los sensores móviles. La concordancia (diferencia media del 95%) entre los dos conjuntos de medidas se ilustró mediante gráficos de Bland-Altman.Resultados: Treinta y cuatro adultos jóvenes asiáticos asintomáticos (15 hombres) participaron en este estudio (Mage ± SD, 24,2 ± 3,82 años). El ICC para el ROM medido por los sensores estuvo entre 0.94 y 0.99, p <0.01 y para las mediciones del goniómetro estuvo entre 0.95 y 0.98, p <0.01 en los cuatro movimientos, lo que indica una excelente confiabilidad en ambos métodos de medición...(AU)


Subject(s)
Humans , Male , Female , Reproducibility of Results , Range of Motion, Articular , Arthrometry, Articular/methods , Physical Therapy Modalities , Upper Extremity , Rehabilitation , Accelerometry
14.
Environ Pollut ; 271: 116394, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33388685

ABSTRACT

Common plasticizers and their alternatives are environmentally ubiquitous and have become a global problem. In this study, common plasticizers (phthalates and metabolites) and new alternatives [bisphenol analogs, t-butylphenyl diphenyl phosphate (BPDP), and bisphenol A bis(diphenyl phosphate) (BDP)] were quantified in urine and hair samples from children in Hong Kong, drinking water (tap water/bottled water) samples, and airborne particle samples from 17 kindergartens in Hong Kong. The results suggested that locally, children were exposed to various plasticizers and their alternatives. High concentrations of BPDP and BDP were present in urine, hair, tap water, bottled water, and air particulate samples. The geometric mean (GM) concentrations of phthalate metabolites in urine samples (126-2140 ng/L, detection frequencies < 81%) were lower than those detected in Japanese and German children in previous studies. However, a comparison of the estimated daily intake values for phthalates in tap water [median: 10.7-115 ng/kg body weight bw/day] and air particles (median: 1.23-7.39 ng/kg bw/day) with the corresponding reference doses indicated no risk. Bisphenol analogs were detected in 15-64% of urine samples at GM concentrations of 5.26-98.1 ng/L, in 7-74% of hair samples at GM concentrations of 57.5-2390 pg/g, in 59-100% of kindergarten air samples at GM concentrations of 43.1-222 pg/m3, and in 33-100% of tap water samples at GM concentrations of 0.90-3.70 ng/L. A significant correlation was detected between the concentrations of bisphenol F in hair and urine samples (r = 0.489, p < .05). The estimated daily urinary excretion values of bisphenol analogs suggest that exposure among children via tap water intake and airborne particle inhalation in kindergartens cannot be ignored in Hong Kong.


Subject(s)
Drinking Water , Phthalic Acids , Child, Preschool , Dust/analysis , Environmental Exposure/analysis , Hong Kong , Humans , Phthalic Acids/analysis , Plasticizers/analysis , Schools
15.
Sci Total Environ ; 764: 142813, 2021 Apr 10.
Article in English | MEDLINE | ID: mdl-33097246

ABSTRACT

Exploiting the full potential of copper-based nanoparticles in the activation of peroxymonopersulfate (PMS) is a great challenge due to their insufficient dispersity and electronic properties. We report here a novel iron­nitrogen co-doped carbon nanotube (FNC) modified with a Cu2O nanocomposite (Cu2O/FNC) that exhibits ultrahigh catalytic performance in the activation of PMS to degrade fluconazole (~95%). Catalytic performance evaluation illustrated that Cu2O/FNC also has wide pH applicability (3.0-11.0), long-term stability and excellent adaptability. In addition, luminescent bacteria toxicity tests confirm that Cu2O/FNC/PMS significantly reduced the acute biotoxicity of various recalcitrant pollutants (reduced by 45-83%). By identifying the reactive oxygen species (ROS) and catalytic performance for various pollutants, we propose that pollutants that interact weekly with activators are mostly destroyed by sulfate radicals and hydroxyl radicals, whilst both radical and non-radical routes were involved in the degradation of pollutants that were easily adsorbed. By modifying Cu2O with FNC, several crucial properties such as the specific surface area, surface defects, active sites and the charge transfer rate were significantly improved, leading to excellent catalytic performance for pollutant removal. Finally, a reasonable reaction mechanism is advanced for the fluconazole degradation pathway. This study not only develops a novel PMS oxidation system for fluconazole degradation, but also provides a new strategy to improve the reactivity and applicability of PMS activators by combining radical and non-radical activation pathways.


Subject(s)
Iron , Nanotubes, Carbon , Electronics , Nitrogen , Peroxides
16.
Bioresour Technol ; 298: 122468, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31839494

ABSTRACT

The difficulty of separating the powdered biochar from the environmental medium may lead to secondary pollution and hinder the large-scale application of biochar as an adsorbent. An effective strategy to solve this bottleneck is to introduce transition metals and their oxides into the biochar matrix, creating easily separable magnetic biochar. Magnetic biochar is also effective for the removal of pollutants from aqueous solution. This review comprises a systematic analysis of 109 papers published in recent years (From 2011 to June 2019), and summarises the synthetic methods and raw materials required for magnetic biochar preparation. The basic physicochemical properties of magnetic biochar are expounded, together with findings from relevant studies, and the application of magnetic biochar as an adsorbent or catalyst in environmental remediation are summarised. Other applications of magnetic biochar are also discussed. Finally, some constructive suggestions are given for the future direction of magnetic biochar research.


Subject(s)
Environmental Restoration and Remediation , Soil Pollutants , Adsorption , Charcoal , Environmental Pollution , Magnetic Phenomena , Soil
17.
J Colloid Interface Sci ; 558: 163-172, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31586736

ABSTRACT

This study examined the relationship between surface oxygen vacancies (OVs) and ceria-based heterogeneous Fenton catalytic activity. Compared with pure iron oxide and ceria, iron-doped ceria with abundant OVs (FeCeOx) exhibits higher rhodamine B (RhB) degradation efficiency (98%) and has a wider applicable pH range (3.0-9.0). The surface hydroxyl radicals are proved to be the predominant reactive species in the oxidation of RhB. Annealing the FeCeOx in an oxygen atmosphere appears to eliminate the OVs, significantly inhibiting the decomposition of H2O2 and the degradation of target pollutants. As multifunctional active sites, OVs are energetically more favorable for the adsorption of reactants than other sites, due to their high electron density. They not only accelerate the Fe(III)/Fe(II) cycle, they also immediately activate H2O2, dissolved oxygen or even water molecules to produce oxidative species, which accounts for the ideal degradation of RhB in the heterogeneous Fenton system. This study clarifies the mechanism of the ceria-based heterogeneous Fenton and provides a better understanding of the surface design of heterogeneous Fenton catalysts.

18.
Environ Int ; 133(Pt B): 105246, 2019 12.
Article in English | MEDLINE | ID: mdl-31675567

ABSTRACT

Benzophenones (BPs) and other ultra violet (UV) filters (UV-filters) are widely used in sunblock and other personal care products, raising concerns about their adverse health risks to human, especially for children. In the present study, BP-type UV-filters and other four widely used UV-filters were evaluated in the child urinary samples (4-6 years, n = 53), tap water and commercial distilled water in Hong Kong. The results suggested that the target chemicals are ubiquitous in the subject. BP1, BP2, BP3 and BP4 in children urine samples contributed closely to the overall children exposure of UV filters, with detection rates above 58% and geometric means ranging from 44.2 to 76.7 ng/mL. As a contrast, BP3 was the major substance found in the tap water and distilled bottle water, with detection rates of 100% and geometric means of 9.64 and 14.5 ng/L, respectively. There were some significant relationships between urinary UV filters and personal characteristics (BMI values, sex, income level, hand washing frequency, and body location usage), but the health risks associated with UV-filters in Hong Kong children might not be concerning. Only two children applied sun creams in this research, indicating that there were other sources to exposure these chemicals.


Subject(s)
Benzophenones/urine , Drinking Water/chemistry , Environmental Exposure/analysis , Sunscreening Agents/analysis , Water Pollutants, Chemical/urine , Benzophenones/analysis , Child, Preschool , Hong Kong , Humans , Water Pollutants, Chemical/analysis
19.
BMC Pulm Med ; 18(1): 133, 2018 Aug 09.
Article in English | MEDLINE | ID: mdl-30092783

ABSTRACT

BACKGROUND: Pneumoconiosis patients receive community-based or home-based pulmonary rehabilitation (PR) for symptom management and enhancement of physical and mental well-being. This study aimed to review the clinical benefits of community-based rehabilitation programmes (CBRP) and home-based rehabilitation programmes (HBRP) for PR of pneumoconiosis patients. METHODS: Archival data of pneumoconiosis patients who participated in CBRP and HBRP between 2008 and 2011 was analysed. There were 155 and 26 patients in the CBRP and HBRP respectively. The outcome measures used in the pre- and post-tests were Knowledge, Health Survey Short Form-12 (SF-12), Hospital Anxiety and Depression Scale (HADS), 6-Min Walk Test (6MWT), and Chronic Respiratory Questionnaire (CRQ). Paired t-tests and the Analysis of Covariance (ANCOVA) using the patients' baseline lung functions as the covariates were performed to examine the changes in the outcomes after completing the programmes. Hierarchical multiple regression analyses were used to examine the relationships between patient's programme participation factors and different scores of the outcome measures. RESULTS: After controlling for patients' baseline lung capacities, significant improvements were revealed among patients participated in CBRP in the scores of the 6MWT, Knowledge, HADS, SF-12 PCS, and CRQ emotion and mastery. The different scores in the Knowledge and HADS were correlated with the patients' levels of programme participation. In contrast, significant improvements were only found in the scores of the Knowledge and 6MWT among patients who participated in HBRP. The gain scores of the 6MWT were correlated with the patients' levels of programme participation. CONCLUSIONS: Both CBRP and HBRP benefited patients' levels of exercise tolerance and knowledge about the disease. CBRP provided greater benefits to patients' mental and psychosocial needs. In contrast, HBRP was found to improve patients' physical function, but did not have significant impacts on patients' mental health and health-related quality of life. The attendance of patients and the participation of their relatives in treatment sessions were important factors in enhancing the positive effects of CBRP and HBRP. These positive outcomes confirm the value of pulmonary rehabilitation programmes for community-dwelling pneumoconiosis patients.


Subject(s)
Exercise Therapy/methods , Home Nursing , Pneumoconiosis/psychology , Pneumoconiosis/rehabilitation , Aged , Aged, 80 and over , Emotions , Exercise Tolerance , Female , Health Surveys , Hong Kong , Humans , Male , Middle Aged , Quality of Life , Regression Analysis , Retrospective Studies , Severity of Illness Index , Walk Test
20.
Environ Sci Pollut Res Int ; 25(3): 2570-2579, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29128943

ABSTRACT

In this study, soil culture experiments were conducted to explore the effects of biochar-supported Ni/Fe nanoparticles on the accumulation and translocation of polybrominated diphenyl ethers (PBDEs) in soil-plant system and its phytotoxicity to Brassica chinensis. Compared with those in BDE209 contaminated soils (S 1) and Ni/Fe nanoparticle-treated soil (S 3), the plant biomass, root, and shoot lengths in biochar-supported Ni/Fe nanoparticle-treated soil (S 4) were increased by 23 mg, 1.35 cm, and 2.08 cm and 27.2 mg, 1.75 cm, and 2.52 cm, respectively, suggesting that the phytotoxicity in S 4 treatment was significantly decreased. Moreover, in all treatments, the contents of BDE209, the total PBDEs, Ni, and Fe in sample plant tissues of S 4 were the lowest. In addition, the superoxide dismutase, peroxidase, and catalase activities in S 4 treatment were found to decrease by 33.8, 47.2, and 24.1%, respectively, compared to those in S 3. Results also showed that biochar addition not only reduced the uptake of PBDEs and heavy metals but also effectively improve soil fertility and reduce the leachability of Ni and Fe caused by Ni/Fe. Finally, the translocation factors (TFs) of PBDEs in four treatments followed the orders as S 1 > S 3 > S 4 > S 2, indicating that biochar has an inhibition effects on PBDE translocation in the plants. In summary, all of the results suggested that the phytotoxicity, translocation of PBDEs, and the negative effects caused by neat Ni/Fe nanoparticles in B. chinensis were decreased as a result of the effects of the biochar.


Subject(s)
Brassica/drug effects , Charcoal/chemistry , Halogenated Diphenyl Ethers/analysis , Iron/chemistry , Metal Nanoparticles/chemistry , Nickel/chemistry , Soil Pollutants/analysis , Biomass , Halogenated Diphenyl Ethers/toxicity , Soil/chemistry , Soil Pollutants/toxicity
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