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1.
Environ Pollut ; 356: 124313, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38838808

RESUMO

N-1,3-Dimethylbutyl-N'-phenyl-p-quinone diamine (6PPDQ) is a derivative of 6PPD, a synthetic antioxidant used in tire manufacturing to control the degradation caused by oxidation and heat aging. Its discovery in 2020 has raised important environmental concern, particularly regarding its association with acute mortality in coho salmon, prompting surge in research on its occurrence, fate, and transport in aquatic ecosystems. Despite this attention, there remain notable gaps in grasping the knowledge, demanding an in depth overview. Thus, this review consolidates recent studies to offer a thorough investigation of 6PPDQ's environmental dynamics, pathways into aquatic ecosystems, toxicity to aquatic organisms, and human health implications. Various aquatic species exhibit differential susceptibility to 6PPDQ toxicity, manifesting in acute mortalities, disruption of metabolic pathways, oxidative stress, behavioral responses, and developmental abnormalities. Whereas, understanding the species-specific responses, molecular mechanisms, and broader ecological implications requires further investigation across disciplines such as ecotoxicology, molecular biology, and environmental chemistry. Integration of findings emphasizes the complexity of 6PPDQ toxicity and its potential risks to human health. However, urgent priorities should be given to the measures like long-term monitoring studies to evaluate the chronic effects on aquatic ecosystems and the establishment of standardized toxicity testing protocols to ensure the result comparability and reproducibility. This review serves as a vital resource for researchers, policymakers, and environmental professionals seeking appraisals into the impacts of 6PPDQ contamination on aquatic ecosystems and human health.


Assuntos
Organismos Aquáticos , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Humanos , Animais , Monitoramento Ambiental/métodos , Quinonas/toxicidade , Ecossistema
2.
Environ Res ; 258: 119492, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38936499

RESUMO

To enhance tire durability, the antioxidant N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) is used in rubber, but it converts into the toxic 6PPD quinone (6PPD-Q) when exposed to oxidants like ozone (O3), causing ecological concerns. This review synthesizes the existing data to assess the transformation, bioavailability, and potential hazards of two tire-derived pollutants 6PPD and 6PPD-Q. The comparative analysis of different thermal methods utilized in repurposing waste materials like tires and plastics into valuable products are analyzed. These methods shed light on the aspects of pyrolysis and catalytic conversion processes, providing valuable perspectives into optimizing the waste valorization and mitigating environmental impacts. Furthermore, we have examined the bioavailability and potential hazards of chemicals used in tire manufacturing, based on the literature included in this review. The bioavailability of these chemicals, particularly the transformation of 6PPD to 6PPD-Q, poses significant ecological risks. 6PPD-Q is highly bioavailable in aquatic environments, indicating its potential for widespread ecological harm. The persistence and mobility of 6PPD-Q in the environment, along with its toxicological effects, highlight the critical need for ongoing monitoring and the development of effective mitigation strategies to reduce its impact on both human health and ecosystem. Future research should focus on understanding the chronic effects of low-level exposure to these compounds on both terrestrial and aquatic ecosystems, as well as the potential for bioaccumulation in the food chain. Additionally, this review outlines the knowledge gaps, recommending further research into the toxicity of tire-derived pollutants in organisms and the health implications for humans and ecosystems.


Assuntos
Borracha , Borracha/química , Poluentes Ambientais/análise , Monitoramento Ambiental
3.
J Hazard Mater ; 472: 134574, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38739959

RESUMO

The pervasive and steadily increasing presence of microplastics/nanoplastics (MPs/NPs) in aquatic environments has raised significant concerns regarding their potential adverse effects on aquatic organisms and their integration into trophic dynamics. This emerging issue has garnered the attention of (eco)toxicologists, promoting the utilization of toxicotranscriptomics to unravel the responses of aquatic organisms not only to MPs/NPs but also to a wide spectrum of environmental pollutants. This review aims to systematically explore the broad repertoire of predicted molecular responses by aquatic organisms, providing valuable intuitions into complex interactions between plastic pollutants and aquatic biota. By synthesizing the latest literature, present analysis sheds light on transcriptomic signatures like gene expression, interconnected pathways and overall molecular mechanisms influenced by various plasticizers. Harmful effects of these contaminants on key genes/protein transcripts associated with crucial pathways lead to abnormal immune response, metabolic response, neural response, apoptosis and DNA damage, growth, development, reproductive abnormalities, detoxification, and oxidative stress in aquatic organisms. However, unique challenge lies in enhancing the fingerprint of MPs/NPs, presenting complicated enigma that requires decoding their specific impact at molecular levels. The exploration endeavors, not only to consolidate existing knowledge, but also to identify critical gaps in understanding, push forward the frontiers of knowledge about transcriptomic signatures of plastic contaminants. Moreover, this appraisal emphasizes the imperative to monitor and mitigate the contamination of commercially important aquatic species by MPs/NPs, highlighting the pivotal role that regulatory frameworks must play in protecting all aquatic ecosystems. This commitment aligns with the broader goal of ensuring the sustainability of aquatic resources and the resilience of ecosystems facing the growing threat of plastic pollutants.


Assuntos
Organismos Aquáticos , Microplásticos , Transcriptoma , Poluentes Químicos da Água , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/genética , Animais , Transcriptoma/efeitos dos fármacos , Nanopartículas/toxicidade , Nanopartículas/química
4.
JACC Case Rep ; 29(5): 102234, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38464793

RESUMO

Early stent thrombosis is a rare complication of percutaneous intervention and is associated with significant 30-day mortality. We present a novel case of multiple recurrent early stent thrombosis consistent with spontaneous vaccine-induced thrombotic thrombocytopenia. We were successfully able to manage this unusual condition through an interdisciplinary collaboration.

5.
Chemosphere ; 342: 140157, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37716553

RESUMO

The perilousness of arsenic and cadmium (As-Cd) toxicity in water and soil presents a substantial hazard to the ecosystem and human well-being. Additionally, this metal (loids) (MLs) can have a deleterious effect on rice quality and yield, owing to the existence of toxic stress. In response to the pressing concern of reducing the MLs accumulation in rice grain, this study has prepared magnesium-manganese-modified corn-stover biochar (MMCB), magnesium-manganese-modified eggshell char (MMEB), and a combination of both (MMCEB). To test the effectiveness of these amendments, several pot trials were conducted, utilizing 1% and 2% application rates. The research discovered that the MMEB followed by MMCEB treatment at a 2% rate yielded the most significant paddy and rice quality, compared to the untreated control (CON) and MMCB. MMEB and MMCEB also extensively decreased the MLs content in the grain than CON, thereby demonstrating the potential to enrich food security and human healthiness. In addition, MMEB and MMCEB augmented the microbial community configuration in the paddy soil, including As-Cd detoxifying bacteria, and decreased bioavailable form of the MLs in the soil compared to the CON. The amendments also augmented Fe/Mn-plaque which captured a considerable quantity of As-Cd in comparison to the CON. In conclusion, the utilization of multifunctional biochar, such as MMEB and MMCEB, is an encouraging approach to diminish MLs aggregation in rice grain and increase rice yield for the reparation of paddy soils via transforming microbiota especially enhancing As-Cd detoxifying taxa, thereby improving agroecology, food security, and human and animal health.

6.
Neuroinformatics ; 20(4): 965-979, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35349109

RESUMO

Degeneracy in biological systems refers to a many-to-one mapping between physical structures and their functional (including psychological) outcomes. Despite the ubiquity of the phenomenon, traditional analytical tools for modeling degeneracy in neuroscience are extremely limited. In this study, we generated synthetic datasets to describe three situations of degeneracy in fMRI data to demonstrate the limitations of the current univariate approach. We describe a novel computational approach for the analysis referred to as neural topographic factor analysis (NTFA). NTFA is designed to capture variations in neural activity across task conditions and participants. The advantage of this discovery-oriented approach is to reveal whether and how experimental trials and participants cluster into task conditions and participant groups. We applied NTFA on simulated data, revealing the appropriate degeneracy assumption in all three situations and demonstrating NTFA's utility in uncovering degeneracy. Lastly, we discussed the importance of testing degeneracy in fMRI data and the implications of applying NTFA to do so.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Humanos
7.
Am J Case Rep ; 22: e933744, 2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34689149

RESUMO

BACKGROUND Intracardiac tumors are a rare entity, with myxomas being the most common among them (approximately 50% of intracardiac tumors). Up to 80% of myxomas originate within the left atrium and while most are incidental or isolated findings in asymptomatic patients, others may result in clinical manifestations of heart failure or emboli. Moreover, in some cases, myxomas can be part of a genetically inherited syndrome known as Carney complex (CNC), and present with varied phenotypes, including skin, endocrine, and neuroendocrine tumors. CASE REPORT We present a case of a 54-year-old male patient who presented with a several-month history of non-specific cough, dyspnea on exertion, and palpitations along with several skin tags, nevi, and nodules. He was found to have a retrocardiac density on chest X-ray, which was revealed to be a large left atrial myxoma on echocardiography. The myxoma was surgically excised and genetic testing for a mutation of the PRKAR1A gene (the most common mutation underlying CNC) was negative. However, 2 major clinical criteria for diagnosis of CNC were fulfilled based on cardiac myxoma and spotty skin pigmentation. In this report, we focus on the clinical manifestations of CNC, including guidance on tumor surveillance and genetic variants of CNC. CONCLUSIONS While CNC is most commonly associated with an inactivating mutation of the PRKAR1A gene, it can be diagnosed clinically in the absence of an identifiable genetic mutation. In patients presenting with atypical cardiac tumors, the early recognition of cutaneous manifestations can raise the index of suspicion for CNC, which can facilitate early diagnosis, treatment, and initiation of surveillance for neoplasia development.


Assuntos
Complexo de Carney , Neoplasias Cardíacas , Mixoma , Complexo de Carney/diagnóstico , Complexo de Carney/genética , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Átrios do Coração , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/genética , Neoplasias Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Mixoma/diagnóstico , Mixoma/genética , Mixoma/cirurgia
8.
Front Cardiovasc Med ; 8: 684780, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336948

RESUMO

Since the first reported case of COVID-19 in December 2019, the global landscape has shifted toward an unrecognizable paradigm. The sports world has not been immune to these ramifications; all major sports leagues have had abbreviated seasons, fan attendance has been eradicated, and athletes have opted out of entire seasons. For these athletes, cardiovascular complications of COVID-19 are particularly concerning, as myocarditis has been implicated in a significant portion of sudden cardiac death (SCD) in athletes (up to 22%). Multiple studies have attempted to evaluate post-COVID myocarditis and develop consensus return-to-play (RTP) guidelines, which has led to conflicting information for internists and primary care doctors advising these athletes. We aim to review the pathophysiology and diagnosis of viral myocarditis, discuss the heterogeneity regarding incidence of COVID myocarditis among athletes, and summarize the current expert recommendations for RTP. The goal is to provide guidance for practitioners who will be managing and advising athletes in the COVID era.

9.
Environ Pollut ; 287: 117600, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34153605

RESUMO

Sulfate (SO4•-) and hydroxyl-based (HO•) radical are considered potential agents for As(III) removal from aquatic environments. We have reported the synergistic role of SO4•- and HO• radicals for As(III) removal via facile synthesis of biochar-supported SO4•- species. MoS2-modified biochar (MoS2/BC), iron oxide-biochar (FeOx@BC), and MoS2-modified iron oxide-biochar (MoS2/FeOx@BC) were prepared and systematically characterized to understand the underlying mechanism for arsenic removal. The MoS2/FeOx@BC displayed much higher As(III) adsorption (27 mg/g) compared to MoS2/BC (7 mg/g) and FeOx@BC (12 mg/g). Effects of kinetics, As(III) concentration, temperature, and pH were also investigated. The adsorption of As(III) by MoS2/FeOx@BC followed the Freundlich adsorption isotherm and pseudo-second-order, indicating multilayer adsorption and chemisorption, respectively. The FTIR and XPS analysis confirmed the presence of Fe-O bonds and SO4 groups in the MoS2/FeOx@BC. Electron paramagnetic resonance (EPR) and radical quenching experiments have shown the generation of SO4•- radicals as predominant species in the presence of MoS2 and FeOx in MoS2/FeOx@BC via radical transfer from HO• to SO42-. The HO• and SO4•- radicals synergistically contributed to enhanced As(III) removal. It is envisaged that As(III) initially adsorbed through electrostatic interactions and partially undergoes oxidation, which is finally adsorbed to MoS2/FeOx@BC after being oxidized to As(V). The MoS2/FeOx@BC system could be considered a novel material for effective removal of As(III) from aqueous environments owing to its cost-effective synthesis and easy scalability for actual applications.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal , Dissulfetos , Compostos Férricos , Ferro , Cinética , Molibdênio , Água , Poluentes Químicos da Água/análise
10.
Chemosphere ; 283: 131102, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34146872

RESUMO

Arsenic (As) and cadmium (Cd) are unnecessary metal(loids) toxic at high concentration to plants and humans, hence lessening their rice grain accumulation is crucial for food security and human healthiness. Charred eggshell (EB), corncob biochar (CB), and eggshell-corncob biochar (ECB) were produced and amended to As and Cd co-polluted paddy soil at 1% and 2% application rates to alleviate the metal(loids) contents in rice grains using pot experiments. All the amendments increased paddy yields at 1%, while EB at 2% significantly reduced the yields compared to untreated control. The resulting yield loss in 2%EB was from the combined effects of its high CaCO3 supplementation, and the increment of rhizosphere soil pH which could insolubilize plant nutrients. The amendments were inefficient in decreasing rice grain As (AsGrain), but all the treatments significantly reduced the rice grain Cd (CdGrain) at both 1% (44.4-77.1%) and 2% (79.8-91.5%) application rates compared to that of control. Regression analysis for contribution weights of control factors revealed that rhizosphere soil Eh and pH were vital influential factors regulating the AsGrain, whereas porewater Cd was main factor controlling CdGrain accumulation. These investigations indicated that the Ca-enriched eggshell-corncob biochar even at high application rate (i.e., 2%ECB) could be a potential tactic for grain accumulation remediation of the cationic pollutant (i.e., Cd) from the paddy soil to rice grain scheme with concurrent increase in rice yields.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Arsênio/análise , Cádmio/análise , Cálcio , Carvão Vegetal , Humanos , Solo , Poluentes do Solo/análise
12.
Sci Total Environ ; 785: 147163, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940407

RESUMO

Arsenic (As) and cadmium (Cd) are nonessential toxic metal(loids) that are carcinogenic to humans. Hence, reducing the bioavailability of these metal(loids) in soils and decreasing their accumulation in rice grains is essential for agroecology, food safety, and human health. Iron (Fe)-enriched corncob biochar (FCB), Fe-enriched charred eggshell (FEB), and Fe-enriched corncob-eggshell biochar (FCEB) were prepared for soil amelioration. The amendment materials were applied at 1% and 2% application rates to observe their alleviation effects on As and Cd loads in rice paddy tissues and yield improvements using pot trials. The FCEB treatment increased paddy yields compared to those of FCB (9-12%) and FEB (3-36%); this could be because it contains more plant essential nutrients than FCB and a lower calcite content than that of FEB. In addition, FCEB significantly reduced brown rice As (AsBR, 29-60%) and Cd (CdBR, 57-81%) contents compared to those of the untreated control (CON). At a 2% application rate, FCEB reduced the average mobility of As (56%) and Cd (62%) in rhizosphere porewater and enhanced root Fe-plaque formation (76%) compared to those of CON. Moreover, the enhanced Fe-plaque sequestered a substantial amount of As (171.4%) and Cd (90.8%) in the 2% FCEB amendment compared to that of CON. Pearson correlation coefficients and regression analysis indicated that two key mechanisms likely control AsBR and CdBR accumulations. First, rhizosphere soil pH and Eh controlled As and Cd availabilities in porewaters and their speciation in the soil. Second, greater Fe-plaque formation in paddy roots grown in the amended soils provided a barrier for plant uptake of the metal(loids). These observations demonstrate that soil amendment with Fe-enriched corncob-eggshell biochar (e.g., 2% FCEB) is a prospective approach for the remediation of metal accumulation from the soil to grain system while simultaneously increasing paddy yield.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Arsênio/análise , Cádmio/análise , Cálcio , Carvão Vegetal , Humanos , Ferro/análise , Solo , Poluentes do Solo/análise
13.
Psychophysiology ; 58(6): e13818, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33768687

RESUMO

Emotional granularity describes the ability to create emotional experiences that are precise and context-specific. Despite growing evidence of a link between emotional granularity and mental health, the physiological correlates of granularity have been under-investigated. This study explored the relationship between granularity and cardiorespiratory physiological activity in everyday life, with particular reference to the role of respiratory sinus arrhythmia (RSA), an estimate of vagal influence on the heart often associated with positive mental and physical health outcomes. Participants completed a physiologically triggered experience-sampling protocol including ambulatory recording of electrocardiogram, impedance cardiogram, movement, and posture. At each prompt, participants generated emotion labels to describe their current experience. In an end-of-day survey, participants elaborated on each prompt by rating the intensity of their experience on a standard set of emotion adjectives. Consistent with our hypotheses, individuals with higher granularity exhibited a larger number of distinct patterns of physiological activity during seated rest, and more situationally precise patterns of activity during emotional events: granularity was positively correlated with the number of clusters of cardiorespiratory physiological activity discovered in seated rest data, as well as with the performance of classifiers trained on event-related changes in physiological activity. Granularity was also positively associated with RSA during seated rest periods, although this relationship did not reach significance in this sample. These findings are consistent with constructionist accounts of emotion that propose concepts as a key mechanism underlying individual differences in emotional experience, physiological regulation, and physical health.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Emoções/fisiologia , Frequência Cardíaca/fisiologia , Arritmia Sinusal Respiratória/fisiologia , Adulto , Eletrocardiografia , Feminino , Humanos , Masculino , Postura , Inquéritos e Questionários , Adulto Jovem
14.
Sci Total Environ ; 771: 144955, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736137

RESUMO

Uranium (U) is a radioactive and highly toxic metal. Its excessive concentrations in the aqueous environments may result in severe and irreversible damage. To fight this hazard, a raw biochar was prepared from Citrullus lanatus L. seeds, then characterized and compared with a MnFe2O4 modified biochar, both tested for U(VI) adsorption from wastewater, which was assayed for the first time in this study. The characterization of the adsorbent materials was performed by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) with elemental mapping, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) techniques. The effects of solution pH, concentration of sorbate and sorbents, temperature, time and ionic strength were assessed as regards their influence on U(VI) adsorption. The experimental adsorption data showed good fit to a pseudo-second-order kinetic model (reaching a value of qe = 15.12 mg g-1, R2 = 0.96 at equilibrium), and to the Langmuir isotherm (achieving a maximum score of qmax = 27.61 mg g-1, R2 = 0.96). The maximum adsorption capacity was found at 318 K. The results of the study indicate that the binding of negatively charged functional groups (carbonyls, hydroxyls, and some carboxylic groups) with MnFe2O4 significantly enhanced U(VI) adsorption. In view of the overall results, it can be concluded that the MnFe2O4 modification of the Citrullus lanatus L. seeds biochar could give an efficient alternative adsorbent for U(VI) removal in a variety of environmental conditions, simultaneously promoting resource utilization and good sustainable management of the materials studied, aiding to protect the environment and human health.


Assuntos
Citrullus , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Humanos , Concentração de Íons de Hidrogênio , Cinética , Sementes , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias
15.
Environ Sci Pollut Res Int ; 28(26): 34979-34989, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33661497

RESUMO

The purpose of this study was to develop a MoS2-impregnated biochar (MoS2@BC) via hydrothermal reaction for adsorption of cadmium (Cd) from an aqueous solution. The prepared adsorbents were characterized, and their abilities to remove Cd(II) were evaluated. The Langmuir and pseudo-second-order models better described the removal of Cd(II) by MoS2@BC. The prepared MoS2@BC exhibited excellent monolayer adsorption capacity. The S-containing functional groups on MoS2@BC enhanced the adsorption of Cd(II). Multiple Cd(II) sorption mechanisms were identified; including Cd(II)-π interactions, ion exchange, electrostatic interaction, and complexation. The dominant mechanism involved Cd-O (38.3%) bonds and Cd-S complexation (61.7%) on MoS2@BC. The as-prepared MoS2@BC is both economical and efficient, making it an excellent material for environmental Cd(II) remediation.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Cádmio/análise , Carvão Vegetal , Cinética , Molibdênio , Poluentes Químicos da Água/análise
16.
PLoS One ; 16(1): e0246428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33513183

RESUMO

Soil phosphorus (P) adsorption and desorption occur in an important endogenous cycle linked with soil fertility problems and relevant to the environmental risk assessment of P. In our study, the effect of long-term inorganic and organic fertilization on P adsorption and desorption characteristics in relation to changes in soil properties was evaluated by selecting three long-term experimental sites in southern China. The selected treatments at each site were CK (unfertilized), NPK (synthetic nitrogen, phosphorus and potassium) and NPKM (synthetic NPK plus manure). The adsorption and desorption characteristics of P were evaluated using Langmuir and Freundlich isotherms. The results showed that long-term application of NPK plus manure significantly increased soil organic carbon (SOC), total P and available P at all three sites compared with the NPK and CK treatments. All three treatments fit these equations well. The maximum adsorption capacity (Qm) of P increased with NPKM treatment, and the binding energy of P (K) and the maximum buffering capacity (MBC) showed increasing trends. NPKM showed the highest Qm (2346.13 mg kg-1) at the Jinxian site, followed by Nanchang (221.16 mg kg-1) and Ningxiang (2219.36 mg kg-1). Compared to CK and NPK, the NPKM treatment showed a higher MBC as 66.64, 46.93 and 44.39 L kg-1 at all three sites. The maximum desorption capacity (Dm) of P in soil was highest with the NPKM treatment (157.58, 166.76, 143.13 mg kg-1), showing a better ability to release P in soil. The correlation matrix showed a significant positive correlation of SOC, total and available P with Qm, Dm and MBC. In conclusion, it is suggested that manure addition is crucial to improve P utilization in red paddy soils within the recommended range to avoid the risk of environmental pollution.


Assuntos
Agricultura , Fertilizantes , Nitrogênio/análise , Fósforo/análise , Solo/química , Adsorção , China
18.
J Environ Sci (China) ; 100: 144-157, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279027

RESUMO

Zero-valent iron amended biochar (ZVIB) has been proposed as a promising material in immobilizing heavy metals in paddy fields. In this study, the impacts of pH of ZVIB (pH 6.3 and pH 9.7) and watering management techniques (watering amount in the order of CON (control, 5/72)>3/72>1-3/72>3/100>1/72, with 5/72, for example, representing irrigation given to 5 cm above soil surface in 72 hr regular interval) on As and Cd bioavailability for rice and its grain yield (YieldBR) were investigated in a pot experiment. Brown rice As (AsBR) content was irrelative to the watering treatments, while significantly decreased (>50%) with the addition of both ZVIB materials. The diminutions of brown rice Cd (CdBR) content as well as the YieldBR were highly dependent on both the soil amendment materials' pH and watering amount. Among all the watering treatments, 3/72 treatment (15% less irrigation water than the CON) with ZVIB 6.3 amendment was the optimum fit for simultaneous reduction of AsBR (50%) and CdBR contents (19%) as well as for significant increment (12%) of the YieldBR. Although high pH (9.7) ZVIB application could also efficiently decrease As and Cd contents in brown rice, it might risk grain yield lost if appropriate (e.g. 3/72 in our study) watering management technique was not chosen. Therefore, ZVIB would be an environmentally friendly option as an amendment material with proper selection of watering management technique to utilize As and Cd co-contaminated arable soils safely for paddy cultivation.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Carvão Vegetal , Concentração de Íons de Hidrogênio , Ferro , Rizosfera , Solo , Poluentes do Solo/análise , Água
19.
Sci Rep ; 10(1): 19828, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188239

RESUMO

Low phosphorus use efficiency (PUE) is one of the main problems of acidic soil that limit the crop growth. Therefore, in the present study, we investigated the response of crop yield and PUE to the long-term application of fertilizers and quicklime (CaO) in the acidic soil under wheat-maize rotation system. Treatments included, CK (no fertilization), NP (inorganic nitrogen and P fertilization), NPK (inorganic N, P and potassium fertilization), NPKS (NPK + straw return), NPCa (NP + lime), NPKCa (NPK + lime) and NPKSCa (NPKS + lime). Results showed that, fertilizer without lime treatments, significantly (p ≤ 0.05) decreased soil pH and crop yield, compared to the fertilizer with lime treatments during the period of 2012-2018. Average among years, compared to the CK treatment, wheat grain yield increased by 138%, 213%, 198%, 547%, 688% and 626%, respectively and maize yield increased by 687%, 1887%, 1651%, 2605%, 5047% and 5077%, respectively, under the NP, NPK, NPKS, NPCa, NPKCa and NPKSCa treatments. Lime application significantly increased soil exchangeable base cations (Ca2+ and Mg2+) and decreased Al3+ cation. Compared to the NP treatment, phosphorus use efficiency (PUE) increased by 220%, 212%, 409%, 807% and 795%, respectively, under the NPK, NPKS, NPCa, NPKCa and NPKSCa treatments. Soil pH showed significant negative relationship with exchangeable Al3+ and soil total N. While, soil pH showed significant (p ≤ 0.05) positive relationship with exchangeable Ca2+, PUE and annual crop yield. PUE was highly negatively correlated with soil exchangeable Al3+. In addition, soil exchangeable Ca2+, pH, exchangeable Al3+ and available N were the most influencing factors of crop yield. Therefore, we concluded that lime application is an effective strategy to mitigate soil acidification and to increase PUE through increasing exchangeable base cations and reducing the acidic cations for high crop yield in acidic soil.

20.
Sci Rep ; 10(1): 20284, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219270

RESUMO

Machine learning methods provide powerful tools to map physical measurements to scientific categories. But are such methods suitable for discovering the ground truth about psychological categories? We use the science of emotion as a test case to explore this question. In studies of emotion, researchers use supervised classifiers, guided by emotion labels, to attempt to discover biomarkers in the brain or body for the corresponding emotion categories. This practice relies on the assumption that the labels refer to objective categories that can be discovered. Here, we critically examine this approach across three distinct datasets collected during emotional episodes-measuring the human brain, body, and subjective experience-and compare supervised classification solutions with those from unsupervised clustering in which no labels are assigned to the data. We conclude with a set of recommendations to guide researchers towards meaningful, data-driven discoveries in the science of emotion and beyond.


Assuntos
Emoções/fisiologia , Modelos Psicológicos , Psicologia/métodos , Aprendizado de Máquina Supervisionado , Aprendizado de Máquina não Supervisionado , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Análise por Conglomerados , Conjuntos de Dados como Assunto , Teoria Fundamentada , Humanos , Imageamento por Ressonância Magnética , Psicofisiologia/estatística & dados numéricos , Autorrelato/estatística & dados numéricos
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