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1.
Behav Brain Res ; 469: 115038, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38705282

RESUMO

There is a trend to study human brain functions in ecological contexts and in relation to human factors. In this study, functional near-infrared spectroscopy (fNIRS) was used to record real-time prefrontal activities in 42 male university student habitual video game players when they played a round of multiplayer online battle arena game, League of Legends. A content-based event coding approach was used to analyze regional activations in relation to event type, physiological arousal indexed by heart rate (HR) change, and individual characteristics of the player. Game events Slay and Slain were found to be associated with similar HR and prefrontal responses before the event onset, but differential responses after the event onset. Ventrolateral prefrontal cortex (VLPFC) activation preceding the Slay onset correlated positively with HR change, whereas activations in dorsolateral prefrontal cortex (DLPFC) and rostral frontal pole area (FPAr) preceding the Slain onset were predicted by self-reported hours of weekly playing (HoWP). Together, these results provide empirical evidence to support the notion that event-related regional prefrontal activations during online video game playing are shaped by game mechanics, in-game dynamics of physiological arousal and individual characteristics the players.


Assuntos
Nível de Alerta , Frequência Cardíaca , Córtex Pré-Frontal , Espectroscopia de Luz Próxima ao Infravermelho , Jogos de Vídeo , Humanos , Masculino , Córtex Pré-Frontal/fisiologia , Adulto Jovem , Nível de Alerta/fisiologia , Frequência Cardíaca/fisiologia , Adulto , Mapeamento Encefálico , Adolescente
2.
Sci Total Environ ; 930: 172738, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38670362

RESUMO

Pesticide usage is a common practice to increase crop yields. Nevertheless, the existence of pesticide residues in the surrounding environment presents a significant hazard to pollinators, specifically the potential undisclosed dangers related to emerging nanopesticides. This study examines the impact of abamectin nanocapsules (AbaNCs), created through electrostatic self-assembly, as an insecticide on honey bees. It was determined that AbaNCs upregulated detoxification genes, including CYP450, as well as antioxidant and immune genes in honey bees. Furthermore, AbaNCs affected the activity of crucial enzymes such as superoxide dismutase (SOD). Although no apparent damage was observed in bee gut tissue, AbaNCs significantly decreased digestive enzyme activity. Microbiome sequencing revealed that AbaNCs disrupted gut microbiome, resulting in a reduction of beneficial bacteria such as Bifidobacterium and Lactobacillus. Additionally, these changes in the gut microbiome were associated with decreased activity of digestive enzymes, including lipase. This study enhances our understanding of the impact of nanopesticides on pollinating insects. Through the revelation of the consequences arising from the utilization of abamectin nanocapsules, we have identified potential stress factors faced by these pollinators, enabling the implementation of improved protective measures.


Assuntos
Microbioma Gastrointestinal , Inseticidas , Ivermectina , Nanocápsulas , Animais , Ivermectina/análogos & derivados , Ivermectina/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Abelhas/fisiologia , Abelhas/efeitos dos fármacos , Inseticidas/toxicidade
3.
Sci Total Environ ; 912: 169318, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38143006

RESUMO

Cadmium (Cd) is a toxic non-essential metal element that can enter the honey bee body through air, water and soil. Currently, there is a lack of sufficient research on the effects of Cd on A. cerana cerana, especially the potential risks of long-term exposure to sublethal concentrations. In order to ascertain the toxicological effects of the heavy metal Cd on bees, we performed laboratory-based toxicity experiments on worker bees and conducted analyses from three distinctive facets: antioxidative, immunological, and gut microbiota. The results showed that exposure of bees to high concentrations of Cd resulted in acute mortality, and the increase in mortality was concentration dependent. In long-term exposure to sublethal concentrations, Cd reduced the number of transcripts of antioxidant genes (AccSOD1, AccTPx3 and AccTPx4) and superoxide dismutase activity, causing an increase in malondialdehyde content. Simultaneously, the transcription of immune-related genes (AccAbaecin and AccApidaecin) and acetylcholinesterase activities was inhibited. Furthermore, Cd changes the structural characteristics of bacterial and fungal communities in the gut, disrupting the balance of microbial communities. In conclusion, the health and survival of honey bees are affected by Cd. This study provides a scientific basis for investigating the toxicological mechanisms and control strategies of the heavy metal Cd on honey bees, while facilitating a better understanding and protection of these valuable honey bees.


Assuntos
Microbioma Gastrointestinal , Himenópteros , Doenças do Sistema Imunitário , Abelhas , Animais , Cádmio/toxicidade , Acetilcolinesterase , Antioxidantes , Estresse Oxidativo
4.
Health Commun ; : 1-12, 2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37574866

RESUMO

Millions of people around the world are affected by mental illness, yet a substantive portion of individuals with mental illness do not regularly seek help from medical professionals or utilize mental health services. Help-seeking involves an individual's communicative intention and behaviors to solicit advice and/or treatment and thus is essentially a communicative process. This manuscript reports a longitudinal study that examined predictors and outcomes of help-seeking in mental illness contexts. Three-wave data from 223 participants clinically diagnosed with one or more mental illness conditions were collected and analyzed. Results indicated that expected outcomes of help-seeking from counselors were significantly associated with participants' communication efficacy and target efficacy at Wave 1, which subsequently influenced motivation to seek help and actual help-seeking behaviors at Wave 2. Actual help-seeking behaviors predicted post-traumatic growth and cognitive reappraisal at Wave 3. Importantly, communication efficacy and target efficacy interacted in their effects on help-seeking motivation and behaviors. Theoretical implications for help-seeking communication processes and practical implications for mental health help-seeking are discussed.

5.
Arthritis Rheumatol ; 75(7): 1187-1202, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36705554

RESUMO

OBJECTIVE: Dysregulated APRIL/BAFF signaling is implicated in the pathogenesis of multiple autoimmune diseases, including systemic lupus erythematosus and lupus nephritis. We undertook this study to develop and evaluate a high-affinity APRIL/BAFF antagonist to overcome the clinical limitations of existing B cell inhibitors. METHODS: A variant of TACI-Fc generated by directed evolution showed enhanced binding for both APRIL and BAFF and was designated povetacicept (ALPN-303). Povetacicept was compared to wild-type (WT) TACI-Fc and related molecules in vitro and in vivo. RESULTS: Povetacicept inhibited APRIL and BAFF more effectively than all evaluated forms of WT TACI-Fc and selective APRIL and BAFF inhibitors in cell-based reporter assays and primary human B cell assays, mediating potent suppression of B cell proliferation, differentiation, and immunoglobulin (Ig) secretion. In mouse immunization models, povetacicept significantly reduced serum immunoglobulin titers and antibody-secreting cells more effectively than anti-CD20 monoclonal antibodies, WT TACI-Fc, or APRIL and BAFF inhibitors. In the NZB × NZW mouse lupus nephritis model, povetacicept significantly enhanced survival and suppressed proteinuria, anti-double-stranded DNA antibody titers, blood urea nitrogen, glomerulonephritis, and renal immunoglobulin deposition. In the bm12 mouse lupus model, povetacicept significantly reduced splenic plasmablasts, follicular helper T cells, and germinal center B cells. In non-human primates, povetacicept was well tolerated, exhibited high serum exposure, and significantly decreased serum IgM, IgA, and IgG levels after a single dose. CONCLUSION: Enhanced APRIL and BAFF inhibition by povetacicept led to greater inhibition of B cell populations critical for autoantibody production compared to WT TACI-Fc and CD20-, APRIL-, or BAFF-selective inhibitors. Potent, dual inhibition by povetacicept has the potential to significantly improve clinical outcomes in autoantibody-related autoimmune diseases.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Camundongos , Animais , Humanos , Autoanticorpos , Fator Ativador de Células B/genética , Linfócitos B , Camundongos Endogâmicos
6.
Brain Sci ; 14(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38248244

RESUMO

Previous studies have demonstrated that individuals with internet gaming disorder (IGD) display abnormal autonomic activities at rest and during gameplay. Here, we examined whether and how in-game autonomic activity is modulated by human characteristics and behavioral performance of the player. We measured heart rate variability (HRV) in 42 male university student habitual gamers (HGs) when they played a round of League of Legends game online. Short-term HRV indices measured in early, middle and late phases of the game were compared between the players at high risk of developing IGD and those at low risk, as assessed by the revised Chen Internet addiction scale (CIAS-R). Multiple linear regression (MLR) was used to identify significant predictors of HRV measured over the whole gameplay period (WG), among CIAS-R, ranking score, hours of weekly playing and selected in-game performance parameters. The high-risk players showed a significantly higher low-frequency power/high-frequency power ratio (LF/HF) relative to the low-risk players, regardless of game phase. MLR analysis revealed that LF/HF measured in WG was predicted by, and only by, CIAS-R. The HRV indicators of sympathetic activity were found to be predicted only by the number of slain in WG (NSlain), and the indicators of parasympathetic activity were predicted by both CIAS-R and NSlain. Collectively, the results demonstrated that risk of developing IGD is associated with dysregulated autonomic balance during gameplay, and in-game autonomic activities are modulated by complex interactions among personal attributes and in-game behavioral performance of the player, as well as situational factors embedded in game mechanics.

7.
Front Microbiol ; 13: 981288, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212834

RESUMO

Water scarcity is a worldwide problem, and in order to obtain plenty of production, agricultural irrigation water accounts for a large portion. Many studies have shown that the interaction of root microorganisms and soil can promote crop growth. Developing ways to reduce irrigation to maintain soil fertility and ensure crop yield by regulating the root microenvironment is an important research goal. Here, we developed a reasonable irrigation plan for eggplant cultivation in a solar greenhouse. The maximum theoretical amount of water demand during eggplant planting obtained from a previous study was used as the control (CK), and the irrigation in the treatments was reduced by 10, 20 and 30% relative to this amount. The 10% irrigation reduction treatment (T1) significantly improved soil nutrients and increased soil catalase, urease and alkaline phosphatase activities (p < 0.05). Further analysis of rhizosphere microorganisms revealed the highest richness and diversity of the microbial community under the T1 treatment, with Bacilli as the most abundant bacteria and Aspergillaceae as the most abundant fungi and lower relative abundances of Chloroflexi and Acidobacteria (p < 0.05). Changes in microbial community structure under the influence of different irrigation treatments resulted in improvements in rhizosphere N cycling and nutrient catabolism. The plant-microbe interactions led to significant increases in eggplant plant height, root vigour, root surface area, leaf chlorophyll a, leaf net photosynthetic rate, water use efficiency, transpiration rate, and stomatal conductance under the T1 treatment compared to the CK treatment; soluble sugar, soluble protein and free amino acid contents in eggplant fruit increased by 10.8, 12.3 and 6.7%, respectively; and yield increased by 3.9%. Our research proved that the 10% irrigation reduction treatment (T1) could improve microbial community richness and fruit yield, which would improve irrigation efficiency and cost reduction in agriculture.

8.
Dalton Trans ; 51(39): 14952-14959, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36111736

RESUMO

Covalent organic frameworks (COFs) have emerged as an extremely promising material for photocatalytic water splitting for hydrogen production. However, their photocatalytic performance is seriously affected by the properties of their donors, acceptors and linkages. So far, few studies have been reported on the key roles of the linkages of a specific COF in improving its photocatalytic hydrogen production performance. Herein, this study designed and synthesized two thiadiazole-based COFs linked by imine and alkyne bonds. The results show that the photocatalytic hydrogen production performance of imine-linked COFs (TeTz-COF1) is 19.6 times higher than that of alkyne-linked COFs (TeTz-COF2). Impressively, TeTz-COF1 achieves an apparent quantum efficiency of 3.5% at 475 nm due to the presence of imine bonds. The experimental results confirm that TeTz-COF1 with imine linkages shows higher photocurrent density, lower photocurrent resistance, and longer fluorescence lifetime than TeTz-COF2 with alkyne linkages. Meanwhile, the well-defined density functional theory (DFT) calculations further suggest that both the imine bond and the acetylene bond belong to the HOMO orbitals. Particularly, the imine bonds endow TeTz-COF1 with more delocalized orbital occupation and smaller work functions, thus leading to its lower excited state energy, stronger carrier separation ability and faster electron migration capability. Both theoretical analysis and the experimental results prove that the presence of imine bonds in TeTz-COF1 can enable the efficient separation and fast transport of photogenerated carriers and high reducing ability of photogenerated electrons. This work may provide important guiding significance for the development of new COFs in the direction of photocatalytic water splitting for hydrogen production.

9.
Insects ; 13(8)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36005365

RESUMO

Insects, as the most abundant animal group on earth, and their symbionts help their hosts to adapt to various environments. Conogethes punctiferalis, Ostrinia furnacalis and Helicoverpa armigera are three main pests co-occurring in the ear stage of corn, which significantly affect the yield and quality of corn. The purpose of this study was to compare the diversity and function of the intestinal bacteria of the three co-occurring lepidopteran pests, C. punctiferalis, O. furnacalis and H. armigera, and to explore the reason of their prevalence from the microbiota's view. Our results showed the difference of diversity and abundance of the gut bacteria of three co-occurring lepidopteran pests at the ear stage. Proteobacteria and Firmicutes were the dominant phyla, and the Enterobacteriaceae and Enterococcaceae were the dominant families in the three pests. Compared with the other two pests, Bacteroidetes was found much more in C. punctiferalis. In addition, C. punctiferalis showed more correlation and similarity in bacteria composition with corn endophytic bacteria, as well as had obvious advantages in metabolic, environmental information processing, cellular processes and organic systems function pathways. Our findings may provide insight into the prevalence of corn earworm larvae from the perspective of gut microbiota and function prediction.

10.
Microbiol Spectr ; 10(4): e0134922, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35950864

RESUMO

Root-associated microorganisms are widely recognized as playing an important role in mitigating stress-induced damage to plants, but the responses of rhizosphere microbial communities after inoculation and their relationship with plant responses remain unclear. In this study, the bacterium Providencia vermicola BR68 and the fungus Sarocladium kiliense FS18 were selected from among 91 strains isolated from the halophyte Suaeda salsa to interact with maize seedlings under salt stress. The results showed that compared with NaCl-only treatment, inoculation with strains BR68 and FS18 significantly improved the growth, net photosynthetic rate, and antioxidant enzyme activities of maize; significantly reduced proline content and generation rate of reactive oxygen species (ROS); and alleviated oxidative stress and osmotic stress. Moreover, inoculation with these two strains increased the activities of soil microbiome enzymes such as sucrase, catalase, and fluorescein diacetate hydrolase, which improved maize physiologies and promoted maize growth under salt stress. In addition, these inoculated strains significantly affected the abundance of certain genera, and the correlation trends for these genera with soil properties and maize physiologies were similar to those of these inoculated strains. Strain BR68 was indirectly associated with bacterial communities through BR-specific biomarkers, and bacterial communities and soil properties explained most of the variation in maize physiologies and growth. Inoculation of strain FS18 was directly associated with variations in soil properties and maize physiologies. The two strains improved maize growth under salt stress and alleviated stress damage in maize in different ways. The links among salt-tolerant microorganisms, soil, and plants established in this study can inform strategies for improving crop cultivation in salinized lands. IMPORTANCE This study demonstrates that halophyte root-associated microorganisms can promote crop tolerance to salt stress and clarify the mechanism by which the strains work in rhizosphere soil. The links among salt-tolerant microorganisms, soil, and plants established in this study can inform strategies for improving crop cultivation in salinized lands.


Assuntos
Chenopodiaceae , Zea mays , Bactérias , Rizosfera , Estresse Salino , Plantas Tolerantes a Sal/microbiologia , Solo , Zea mays/microbiologia
11.
Aquat Toxicol ; 249: 106218, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35704967

RESUMO

Arsenic pollution in freshwater poses a serious threat to aquatic organisms. However, dissolved organic matter (DOM) in water can modulate arsenic environmental toxicity by either suppressing or promoting its bioaccumulation. In this study, we investigated the toxicity, bioaccumulation, and biotransformation of inorganic arsenic (arsenite AsIII and arsenate AsV) combined with two types of DOM, i.e., humic acid (HA) and fulvic acid (FA), in the algae Chlamydomonas reinhardtii and Ochromonas danica. C. reinhardtii has a cell wall and cannot bioaccumulate arsenic complexation, whereas O. danica has no cell wall. Without DOM, AsV was more toxic than AsIII for C. reinhardtii, and AsV was less toxic than AsIII for O. danica. HA and FA addition reduced AsV and AsIII toxicities; the larger molecular weight (Mw) of HA contributed to the reduction in toxicity to an even greater extent, and reduced arsenic accumulation while promoting the biotransformation ability of C. reinhardtii, which has a cell wall. However, HA and FA addition increased AsV and AsIII toxicities and arsenic accumulation while relatively enhancing the biotransformation ability of O. danica, which has no cell wall. Coupling toxicity, bioaccumulation, and biotransformation, DOM (HA and FA) contributed to the altered toxicity of freshwater algae to AsV and AsIII through reduced/increased arsenic accumulation and enhanced biotransformation. Overall, our study considered the combined toxicity of inorganic arsenic and DOM in phytoplankton, helping estimate the potential environmental risk of arsenic in aqueous environments.


Assuntos
Arsênio , Arsenicais , Arsenitos , Poluentes Químicos da Água , Arseniatos/metabolismo , Arseniatos/toxicidade , Arsênio/toxicidade , Arsenitos/metabolismo , Arsenitos/toxicidade , Biotransformação , Água Doce , Substâncias Húmicas , Poluentes Químicos da Água/toxicidade
12.
Environ Int ; 163: 107221, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35378441

RESUMO

Arsenic exists universally in freshwater and marine environments, threatening the survival of aquatic organisms and human health. To elucidate arsenic bioaccumulation and biotransformation processes in aquatic organisms, this review evaluates the dissolved uptake, dietary assimilation, biotransformation, and elimination of arsenic in aquatic organisms and discusses the major factors influencing these processes. Environmental factors such as phosphorus concentration, pH, salinity, and dissolved organic matter influence arsenic absorption from aquatic systems, whereas ingestion rate, gut passage time, and gut environment affect the assimilation of arsenic from foodstuffs. Arsenic bioaccumulation and biotransformation mechanisms differ depending on specific arsenic species and the involved aquatic organism. Although some enzymes engaged in arsenic biotransformation are known, deciphering the complicated synthesis and degradation pathway of arsenobetaine remains a challenge. The elimination of arsenic involves many processes, such as fecal excretion, renal elimination, molting, and reproductive processes. This review facilitates our understanding of the environmental behavior and biological fate of arsenic and contributes to regulation of the environmental risk posed by arsenic pollution.


Assuntos
Arsênio , Poluentes Químicos da Água , Organismos Aquáticos/metabolismo , Arsênio/análise , Bioacumulação , Biotransformação , Humanos , Poluentes Químicos da Água/análise
13.
Arthritis Res Ther ; 24(1): 13, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986869

RESUMO

BACKGROUND: Uncontrolled immune response with T cell activation has a key role in the pathogenesis of systemic sclerosis (SSc), a disorder that is characterized by generalized fibrosis affecting particularly the lungs and skin. Costimulatory molecules are key players during immune activation, and recent evidence supports a role of CD28 and ICOS in the development of fibrosis. We herein investigated the efficacy of acazicolcept (ALPN-101), a dual ICOS/CD28 antagonist, in two complementary SSc-related mouse models recapitulating skin fibrosis, interstitial lung disease, and pulmonary hypertension. METHODS: Expression of circulating soluble ICOS and skin-expressed ICOS was investigated in SSc patients. Thereafter, acazicolcept was evaluated in the hypochlorous acid (HOCL)-induced dermal fibrosis mouse model and in the Fra-2 transgenic (Tg) mouse model. In each model, mice received 400 µg of acazicolcept or a molar-matched dose of an Fc control protein twice a week for 6 weeks. After 6 weeks, skin and lung were evaluated. RESULTS: ICOS was significantly increased in the sera from SSc patients and in SSc skin biopsies as compared to samples from healthy controls. Similar body weight changes were observed between Fc control and acazicolcept groups in both HOCL and Fra-2 Tg mice suggesting a good tolerance of acazicolcept treatment. In mice challenged with HOCL, acazicolcept induced a significant decrease in dermal thickness, collagen content, myofibroblast number, and inflammatory infiltrates characterized by B cells, T cells, neutrophils, and macrophages. In the Fra-2 Tg mouse model, acazicolcept treatment reduced lung collagen content, fibrillar collagen, histological fibrosis score, and right ventricular systolic pressure (RVSP). A reduction in frequency of CD4+ and T effector memory cells and an increase in the percentage of CD4+ T naïve cells in spleen and lung of acazicolcept-treated Fra-2 Tg mice was observed as compared to Fc control-treated Fra-2 Tg mice. Moreover, acazicolcept reduced CD69 and PD-1 expression on CD4+ T cells from the spleen and the lung. Target engagement by acazicolcept was demonstrated by blockade of CD28 and ICOS detection by flow cytometry in treated mice. CONCLUSIONS: Our results confirm the importance of costimulatory molecules in inflammatory-driven fibrosis. Our data highlight a key role of ICOS and CD28 in SSc. Using complementary models, we demonstrated that dual ICOS/CD28 blockade by acazicolcept decreased dermal and pulmonary fibrosis and alleviated pulmonary hypertension. These results pave the way for subsequent research on ICOS/CD28-targeted therapies.


Assuntos
Antígenos CD28/antagonistas & inibidores , Proteína Coestimuladora de Linfócitos T Induzíveis/antagonistas & inibidores , Escleroderma Sistêmico , Anticorpos de Cadeia Única/farmacologia , Animais , Antígenos CD28/metabolismo , Modelos Animais de Doenças , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Camundongos , Camundongos Transgênicos , Fibrose Pulmonar/metabolismo , Escleroderma Sistêmico/tratamento farmacológico , Escleroderma Sistêmico/patologia , Pele/patologia
14.
Environ Pollut ; 292(Pt A): 118254, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610412

RESUMO

The San Joaquin Valley (SJV) of California has suffered persistent particulate matter (PM) pollution despite many years of control efforts. To further understand the chemical drivers of this problem and to support the development of State Implementation Plan for PM, a time-of-flight aerosol chemical speciation monitor (ToF-ACSM) outfitted with a PM2.5 lens and a capture vaporizer has been deployed at the Fresno-Garland air monitoring site of the California Air Resource Board (CARB) since Oct. 2018. The instrument measured non-refractory species in PM2.5 continuously at 10-min resolution. In this study, the data acquired from Oct. 2018 to May 2019 were analyzed to investigate the chemical characteristics, sources and atmospheric processes of PM2.5 in the SJV. Comparisons of the ToF-ACSM measurement with various co-located aerosol instruments show good agreements. The inter-comparisons indicated that PM2.5 in Fresno was dominated by submicron particles during the winter whereas refractory species accounted for a major fraction of PM2.5 mass during the autumn associated with elevated PM10 loadings. A rolling window positive matrix factorization analysis was applied to the organic aerosol (OA) mass spectra using the Multilinear Engine (ME-2) algorithm. Three distinct OA sources were identified, including vehicle emissions, local and regional biomass burning, and formation of oxygenated species. There were significant seasonal variations in PM2.5 composition and sources. During the winter, residential wood burning and oxidation of nitrogen oxides were major contributors to the occurrence of haze episodes with PM2.5 dominated by biomass burning OA and nitrate. In autumn, agricultural activities and wildfires were found to be the main cause of PM pollution. PM2.5 concentrations decreased significantly after spring and were dominated by oxygenated OA during March to May. Our results highlight the importance of using seasonally dependent control strategies to mitigate PM pollution in the SJV.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Nebulizadores e Vaporizadores , Material Particulado/análise
15.
Mater Sci Eng C Mater Biol Appl ; 116: 111259, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806304

RESUMO

The conventional preparation method of natural polymers is low in strength, which limits the application of multi stimuli responsive hydrogels as intelligent wound dressings. In this work, interpenetrating gelatin and γ-polyglutamic acid (γ-PGA) hydrogels with good biocompatibility, biodegradability and mechanical properties were prepared by hot-pressing pre-gelation of gelatin/γ-PGA and synergistic with gamma irradiation. The effects of radiation crosslinking dosage on gel fraction, swelling ratio, tensile strength and surface morphology were investigated. The biocompatibility of radiation cross-linked hydrogel was evaluated by aseptic test, hemolysis test, cytotoxicity test, delayed hypersensitivity reaction as well as in vivo degradation studies from in vitro to in vivo. The optimized hydrogel irradiated by 25 kGy has good water retention and biodegradability, especially the stimulation of temperature, pH value, salt species and concentration. The mechanical strength, biocompatibility and responsive properties of the hydrogel indicate that the intelligent hydrogel prepared by this method is a good hydrogel biomaterial for developing interactive wound dressing.


Assuntos
Gelatina , Hidrogéis , Bandagens , Materiais Biocompatíveis/farmacologia , Ácido Glutâmico
16.
Sci Total Environ ; 749: 141603, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-32829280

RESUMO

Although more attention has been paid to plastic pollution in marine ecosystems, research on the influence of plastic in freshwater ecosystems remains limited. To help fill this information gap, this article represents an investigation of the effects of virgin polyvinyl chloride (v-PVC) microplastics (MPs) and UV-aged polyvinyl chloride (a-PVC) MPs on the growth and chlorophyll content of the freshwater algae, Chlamydomonas reinhardtii (C. reinhardtii) at different periods (0, 24, 48, 72 and 96 h). The results suggest that both virgin and aged PVC MPs have negative effects on the growth of C. reinhardtii in the range of 10 mg/L to 200 mg/L, which leads to the reduction of chlorophyll-a level in the cells. Furthermore, a-PVC MPs were more toxic than v-PVC MPs, as shown by the a-PVC MPs' lower EC50 values after 96 h (63.66 mg/L for a-PVC MPs and 104.93 mg/L for v-PVC MPs). The inhibition effect of both kinds of PVC was also testified by the enhancement of enzymatic activity of superoxide dismutase (SOD) and malondialdehyde (MDA) in algae. Meanwhile, a-PVC MPs obviously had a higher toxicity than v-PVC MPs. The aging process that affected the surface characteristics of a-PVC was identified using Fourier transform infrared (FTIR) and Zetasizer. The carbonyl groups formed on the surface and the increased zeta potential of the a-PVC MPs affected the interaction between the microplastics and the algae, which increased the toxicity of aged microplastics. The research results presented here provide more evidence of the risks microplastics bring into the freshwater ecosystem.


Assuntos
Chlamydomonas reinhardtii , Poluentes Químicos da Água , Ecossistema , Água Doce , Microplásticos , Plásticos/toxicidade , Cloreto de Polivinila/toxicidade , Poluentes Químicos da Água/toxicidade
17.
Front Microbiol ; 11: 1435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32774328

RESUMO

Parasitism is a special interspecific relationship in insects. Unlike most other ectoparasites, Nasonia vitripennis spend most of its life cycle (egg, larvae, pupae, and early adult stage) inside the pupae of flies, which is covered with hard puparium. Microbes play important roles in host development and help insect hosts to adapt to various environments. How the microbes of parasitic wasp respond to different fly hosts living in such close relationships motivated this investigation. In this study, we used N. vitripennis and three different fly pupa hosts (Lucilia sericata, Sarcophaga marshalli, and Musca domestica) to address this question, as well as to illustrate the potential transfer of bacteria through the trophic food chains. We found that N. vitripennis from different fly pupa hosts showed distinct microbiota, which means that the different fly hosts could affect the bacterial communities of their parasitic wasps. Some bacteria showed potential horizontal transfer through the trophic food chains, from the food through the fly to the parasitic wasp. We also found that the heritable endosymbiont Wolbachia could transferred from the fly host to the parasite and correlated with the bacterial communities of the corresponding parasitic wasps. Our findings provide new insight to the microbial interactions between parasite and host.

18.
RSC Adv ; 10(64): 39072-39079, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-35518390

RESUMO

To evaluate a novel lamellar structural biomaterial as a potential biomaterial for guided bone regeneration, we describe the preparation of a collagen membrane with high mechanical strength and anti-enzyme degradation ability by using the multi-level structure of Ctenopharyngodon idella scales. The physical and chemical properties, in vitro degradation, biocompatibility, and in vivo osteogenic activity were preliminarily evaluated. In conclusion, it was shown that the multi-layered collagen structure material had sufficient mechanical properties, biocompatibility, and osteogenic ability. Meanwhile, it is also shown that there is a gap in current clinical needs, between the guided tissue regeneration membrane and the one being used. Therefore, this study provides useful insights into the efforts being made to design and adjust the microstructure to balance its mechanical properties, degradation rate, and osteogenic activity.

19.
Environ Sci Technol ; 54(1): 92-101, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31840985

RESUMO

The rapid decrease in Arctic sea ice is motivating development and increasing oil and gas extraction activities. However, few observations of these local Arctic emissions exist, limiting the understanding of impacts on atmospheric composition and climate. To address this knowledge gap, the chemical composition of atmospheric aerosols was measured within the North Slope of Alaska oil fields during August and September 2016 using an aerosol time-of-flight mass spectrometer (ATOFMS) and a time-of-flight aerosol chemical speciation monitor (ToF-ACSM). Plumes from oil and gas extraction activities were characterized by soot internally mixed with sulfate (matching diesel soot) and organic carbon particles containing aminium sulfate salts. Sea spray aerosol at the coastal site was frequently internally mixed with sulfate and nitrate, from multiphase chemical processing from elevated NOx and SO2 within the oil field. Background (nonplume) air masses were characterized by aged combustion aerosol. No periods of "clean" (nonpolluted) Arctic air were observed. The composition of the nonrefractory aerosol measured with the ACSM was similar during plume and background periods and was consistent with the mass concentrations of nonrefractory particles measured by ATOFMS. Two ultrafine aerosol growth events were observed during oil field background periods and were correlated with fine mode amine-containing particles.


Assuntos
Poluentes Atmosféricos , Fuligem , Aerossóis , Alaska , Aminas , Monitoramento Ambiental , Campos de Petróleo e Gás , Tamanho da Partícula , Sulfatos , Ésteres do Ácido Sulfúrico
20.
Cyberpsychol Behav Soc Netw ; 22(11): 677-683, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31697597

RESUMO

Reducing the rate of college binge drinking is a major public health goal. Social media sites such as Facebook serve as platforms for young adults' online communication, so they could potentially extend the reach of health campaign messages via retransmission. Thus, it is important to identify the factors that predict intentions to share health-related messages on social media. Drawing on the Spiral of Silence framework, the current research examined the effects of opinion climate, message efficacy, and publicness of social media on message retransmission intentions for anti-binge drinking "how-to" messages-messages that include advice and recommendations that target beliefs about efficacy. A 2 × 2 × 2 (efficacy: high vs. low × opinion climate: support vs. oppose × channel: public vs. private) between-subjects experiment was conducted. Data from 245 participants on Amazon Mechanical Turk demonstrated that people were more willing to share when they had an anti- rather than a pro-binge drinking opinion climate, when the messages were more useful, and when they were asked to share via private messaging rather than via public status updates. Theoretical and practical implications for the psychological mechanisms underlying message retransmission on social media are discussed.


Assuntos
Consumo de Álcool na Faculdade/psicologia , Consumo Excessivo de Bebidas Alcoólicas/prevenção & controle , Intenção , Mídias Sociais , Adolescente , Adulto , Consumo Excessivo de Bebidas Alcoólicas/psicologia , Feminino , Promoção da Saúde , Humanos , Masculino , Universidades , Adulto Jovem
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