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1.
Nano Lett ; 24(22): 6665-6672, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38767991

RESUMO

Shape morphing of biopolymer materials, such as chitosan (CS) films, has great potential for applications in many fields. Traditionally, their responsive behavior has been induced by the differential water swelling through the preparation of multicomponent composites or cross-linking as deformation is not controllable in the absence of these processes. Here, we report an interfacial dehydration strategy to trigger the shape morphing of the monocomponent CS film without cross-linking. The release of water molecules is achieved by spraying the surface with a NaOH solution or organic solvents, which results in the interfacial shrinkage and deformation of the entire film. On the basis of this strategy, a range of CS actuators were developed, such as soft grippers, joint actuators, and a light switch. Combined with the geometry effect, edited deformation was also achieved from the planar CS film. This shape-morphing strategy is expected to enable the application of more biopolymers in a wide range of fields.

2.
Nat Comput Sci ; 4(3): 169-177, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38532139

RESUMO

Digital twins, which are considered an effective approach to realize the fusion between virtual and physical spaces, have attracted a substantial amount of attention in the past decade. With their rapid development in recent years, digital twins have been applied in various fields, particularly in industry. However, there are still some gaps to be filled and some limitations to be addressed. Here we provide a brief overview of digital twin advancements in industry and highlight the main pitfalls to avoid and challenges to overcome, to improve the maturity of digital twins and facilitate large-scale industrial applications in the future.

3.
Biol Trace Elem Res ; 200(4): 1750-1762, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34185276

RESUMO

Mastitis caused by Staphylococcus aureus infection not only causes serious economic losses, but also affects human health. Se plays an important role in body immunity. However, the mechanisms by which Se regulates mastitis induced by S. aureus are still principally unknown. The purpose of this study is to investigate whether Se can inhibit mastitis induced by S. aureus through regulation of MerTK. Sixty BALB/c female mice were fed low, normal, or high Se concentrations for 7 weeks and then randomly divided into six groups (Se-Low Control group (LSN), Se-Normal Control group (NSN), Se-High Control group (HSN), Se-Low S. aureus group (LSS), Se-Normal S. aureus group (NSS), Se-High S. aureus group (HSS)). The regulation of Se on MerTK was detected via histopathological staining, western blot analysis, enzyme-linked immunosorbent assay, and qRT-PCR. With increased selenium concentrations, the levels of IL-1ß, IL-6, and TNF-α decreased, while the phosphorylation levels of MerTK, PI3K, AKT, and mTOR increased. Therefore, this study showed that Se could alleviate S. aureus mastitis by activating MerTK and PI3K/AKT/mTOR pathway.


Assuntos
Mastite , Selênio , Infecções Estafilocócicas , Animais , Feminino , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mastite/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Selênio/metabolismo , Selênio/farmacologia , Infecções Estafilocócicas/metabolismo , Staphylococcus aureus/metabolismo , Serina-Treonina Quinases TOR , c-Mer Tirosina Quinase
4.
Sci Total Environ ; 781: 146697, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-33794465

RESUMO

Para-nitrophenol (PNP) is often detected in industrial wastewater that is discharged into municipal wastewater treatment plants. Intermittent discharge of PNP into municipal treatment facilities puts their biological process at risk of inhibition, and the risk is especially great for nitrification. In this work, nitrifying biomass was acclimated to PNP. The acclimated biomass retained most of its ammonium-removal activity when it was exposed to PNP at up to 100 mg/L, while the normal (unacclimated) biomass had nearly complete inhibition. PNP was effectively biodegraded by the acclimated biomass, but the normal biomass had minimal PNP biodegradation. After PNP disappeared, the acclimated biomass recovered its ability for NH4+-N removals within one to two days, but the normal biomass did not fully recovery even after seven days. The acclimated biomass had superior ability to sustain nitrification due to its ability to biodegrade PNP and its selection of nitrifying bacteria more resistant to PNP. The PNP-acclimated community was enriched in genera that could have been active in the biodegradation of PNP, such as Chloroflexi. Although the abundance of well-known nitrifiers, Nitrosomonas and Nitrospira, decreased, Nitrosospira and other genera within the Proetobacteria phylum increased, presumably because they were more resistant to PNP.


Assuntos
Nitrificação , Esgotos , Biomassa , Reatores Biológicos , Nitrofenóis/toxicidade , Nitrosomonas
5.
Toxicol Ind Health ; 37(4): 229-239, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33724083

RESUMO

This study quantitatively evaluated the effects of pyrethroid pesticides on the testis of male rats. An extensive literature search for relevant studies was conducted on PubMed, Web of Science, Excerpta Medica Database, the Chinese National Knowledge Infrastructure, and Chinese Biomedical Literature Database. Pooled standard mean difference with corresponding 95% confidence interval was calculated via the random-effects model. I 2 was used to evaluate heterogeneity among studies. A total of 19 studies were included for analysis in our study. Results indicated that the sperm count of rats exposed to fenvalerate was lower than that of rats in control groups. The sperm count, sperm motility, and testosterone level of rats exposed to cypermethrin and deltamethrin were lower than those of rats in control groups. Moreover, the sperm morphology of rats exposed to these pyrethroid pesticides was abnormal compared with that of rats in control groups. The present meta-analysis indicates that pyrethroid pesticides decrease rat sperm count, sperm motility, and testosterone level and cause abnormal rat sperm morphology. Therefore, pyrethroid pesticides can damage the testis of male rats.


Assuntos
Inseticidas/toxicidade , Piretrinas/toxicidade , Testículo/efeitos dos fármacos , Animais , Masculino , Ratos , Espermatozoides/efeitos dos fármacos , Testosterona/toxicidade
6.
Pathogens ; 9(12)2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33276616

RESUMO

Bamboo rats (Rhizomys sinensis) are widely farmed in Guangdong, China, but the distribution and public health potential of Cryptosporidium spp. in them are unclear. In this study, 724 fecal specimens were collected from bamboo rats in Guangdong Province and analyzed for Cryptosporidium spp. using PCR and sequence analyses of the small subunit rRNA gene. The overall detection rate of Cryptosporidium spp. was 12.2% (88/724). By age, the detection rate in animals under 2 months (23.2% or 13/56) was significantly higher than in animals over 2 months (11.2% or 75/668; χ2 = 6.95, df = 1, p = 0.0084). By reproduction status, the detection rate of Cryptosporidium spp. in nursing animals (23.1% or 27/117) was significantly higher than in other reproduction statuses (6.8% or 4/59; χ2 = 7.18, df = 1, p = 0.0074). Five Cryptosporidium species and genotypes were detected, including Cryptosporidium bamboo rat genotype I (n = 49), C. parvum (n = 31), Cryptosporidium bamboo rat genotype III (n = 5), C. occultus (n = 2), and C. muris (n = 1). The average numbers of oocysts per gram of feces for these Cryptosporidium spp. were 14,074, 494,636, 9239, 394, and 323, respectively. The genetic uniqueness of bamboo rat genotypes I and III was confirmed by sequence analyses of the 70 kDa heat shock protein and actin genes. Subtyping C. parvum by sequence analysis of the 60 kDa glycoprotein gene identified the presence of IIoA15G1 (n = 20) and IIpA6 (n = 2) subtypes. The results of this study indicated that Cryptosporidium spp. are common in bamboo rats in Guangdong, and some of the Cryptosporidium spp. in these animals are known human pathogens.

7.
Water Res ; 185: 116285, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798897

RESUMO

Many municipal wastewater treatment plants in China receive industrial wastewater that contains inhibitory organic chemicals, such as chlorinated phenols. For the common aerobic biological treatment, nitrification is a key step, but nitrifying bacteria are notably sensitive to inhibition by chlorinated phenols. In this work, normal activated sludge (containing nitrifying biomass) was acclimated to 2,4,6-trichlorophenol (TCP). The acclimated biomass had more than 2-fold faster nitrification kinetics than normal biomass when exposed to TCP, and it also achieved effective TCP removal in parallel. When suddenly exposed to TCP after as much as two months without TCP input, the acclimated nitrifying biomass retained effective nitrification and TCP biodegradation: The nitrification rate and TCP removal rate were 0.325 mM/h and 0.049 mM/h for the acclimated biomass, compared to only 0.165 mM/h and 0.001 mM/h for normal biomass. Resistance to TCP inhibition also was retained for 5 generations of sub-culturing without TCP exposure. High-throughput sequencing confirmed that the acclimated biomass contained nitrifying bacteria and heterotrophic bacteria capable of degrading TCP, although the key genera changed during sub-culturing.


Assuntos
Clorofenóis , Aclimatação , Biomassa , Reatores Biológicos , China , Nitrificação , Esgotos
8.
Sci Total Environ ; 693: 133622, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31376758

RESUMO

It is common that biological wastewater-treatment processes are exposed to inputs of toxic compounds, such as phenolics. Due to their slow growth rate, nitrifying bacteria are most susceptible to inhibition that can lead to loss of nitrification capacity. Here, a microbial community containing nitrifying bacteria was acclimated to phenol, and it developed resistance to phenol inhibition and maintained nitrification activity. For the phenol-acclimated biomass, the NH4+-N removal rates were almost unaffected when it was suddenly exposed to phenol. Heterotrophic synthesis and nitrification rates contributed 76% and 24% of the total NH4+-N removal respectively during phenol removal, but the nitrification rate increased significantly once phenol was removed and mineralized. In contrast, the NH4+-N removal rates decreased sharply for normal (unacclimated) nitrifying biomass when it was exposed to phenol. The phenol-acclimated biomass retained its resistance to phenol inhibition for at least two months after acclimation, and addition of the phenol-acclimated biomass to the normal biomass conferred resistance to phenol inhibition. Community analysis of the phenol-acclimated biomass showed an increase in families known to contain strains able to biodegrade phenolics. Taken together, the results indicate that the main impact of phenol acclimation was enrichment of phenol-biodegrading bacteria, which allowed rapid removal and mineralization of phenol and, consequently, alleviation of phenol's inhibition of nitrification.


Assuntos
Biodegradação Ambiental , Nitrificação/fisiologia , Fenol/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Águas Residuárias/microbiologia
9.
J Environ Manage ; 233: 561-566, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597349

RESUMO

Activated sludge treated by ultrasound was tested as a source of exogenous electron donor to accelerate quinoline mono-oxygenation, which requires an intracellular electron donor (2H). The quinoline-removal rate was proportional to the amount of treated or untreated sludge added in flask experiments, but the best biodegradation kinetics was obtained with a mixture of 25% untreated sludge plus 75% treated sludge. The treated sludge primarily provided exogenous electron donor, while the untreated sludge provided active biomass. A biofilm system also showed the same beneficial effect of treated sludge, and the soluble fraction of the treated sludge had the greatest impact. Using treated sludge instead of a purchased electron donor provides an economic advantage for accelerating the biodegradation of contaminants whose biodegradation is initiated by an oxygenation reaction, such as quinoline.


Assuntos
Quinolinas , Esgotos , Biodegradação Ambiental , Biofilmes , Reatores Biológicos , Cinética
10.
Sci Total Environ ; 654: 473-479, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30447586

RESUMO

Fallen leaves of Platanus orientalis and Ginkgo biloba linn were separately immersed in water to obtain leachates that were used as exogenous electron donors for accelerating pyridine and quinoline biodegradations. Leachate addition accelerated the pyridine removal rate by up to 4.4% and 3.6% and the quinoline removal rate by 9.5% and 11%. The rates increased further after the leachates were illuminated by UV light: up to 8.5% for pyridine and 12% for quinoline. Succinate and oxalate were separately added into solutions of pyridine and quinoline (respectively) to gauge the acceleration impact of the leaf leachates. Equations describing the relationships between addition of leachate and pyridine or quinoline removal rates were established based on electron-equivalent balances and comparison to the acceleration effects from succinate and oxalate. From 22% to 98% of the COD leached from leaves was available as an electron donor, with the fraction being greater for pyridine and after UV illumination.


Assuntos
Elétrons , Poluentes Ambientais/metabolismo , Oxigênio/metabolismo , Folhas de Planta/química , Piridinas/metabolismo , Quinolinas/metabolismo , Raios Ultravioleta , Animais , Biodegradação Ambiental , Disponibilidade Biológica , Ginkgo biloba/metabolismo , Magnoliopsida/metabolismo , Árvores/metabolismo
11.
J Environ Manage ; 226: 264-269, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30121462

RESUMO

Aerobic biodegradation of nitrobenzene (NB) produces nitrophenol (NP), which has stronger toxicity than NB. Anaerobic biodegradation of NB produces aniline (AN), which has weaker toxicity, but is a dead-end product in anaerobic conditions. Accumulation of AN should be overcome by coupling anaerobic and aerobic transformations: NB is transformed to AN in an anaerobic zone of the bioreactor, and AN is then transformed in an aerobic zone. A vertical baffled bioreactor (VBBR) was employed for NB biodegradation with a controlled dissolved oxygen (DO) concentration. NB biodegradation was accelerated by simultaneous anaerobic and aerobic transformations, since AN was biotransformed by a mono-oxygenase reaction. Adding exogenous electron donor (acetate) enhanced NB removals when the DO concentration was ∼0.5 mg/L, because the donor accelerated mono-oxygenations of NB and AN. Coupling anaerobic and aerobic transformations can be a valuable strategy for biodegrading organic compounds that undergo aerobic and anaerobic biotransformations.


Assuntos
Biodegradação Ambiental , Reatores Biológicos , Nitrobenzenos/química , Biotransformação , Nitrofenóis
12.
Neuropsychology ; 32(6): 764-776, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30047755

RESUMO

OBJECTIVE: Impaired nucleus accumbens (NAcc) activation is associated with amotivation and anhedonia, which are resistant to treatment with antipsychotics and antidepressants in schizophrenia. In this study, healthy participants were trained to self-regulate the activation of their NAcc, a brain region that plays an important role in motivation, using real-time functional magnetic resonance imaging (fMRI) neurofeedback. METHOD: The experimental group (N = 19) received feedback from the NAcc, whereas the control group (N = 5) received "sham" feedback from the posterior parahippocampal gyrus, a control brain region not normally related to motivation. All participants were trained to use mental strategies to regulate their NAcc activations in a 3T MRI scanner. RESULTS: For the learning effect of NAcc regulation, we found that the majority of participants (74%) in the experimental group successfully learned to self-regulate the NAcc. They also showed improved behavioral performance in motivation and decreased functional connectivity between the NAcc and the ventral medial prefrontal cortex and an increase in small-world properties in the reward circuit after training, indicating improved information integration in reward processing. However, improvement in motivation and modification of function connectivity were not observed in the sham control group and the participants who failed to self-regulate the NAcc in the experimental group. Self-regulation was influenced by the baseline motivation. CONCLUSIONS: These findings suggest that the NAcc could be self-regulated using real-time fMRI neurofeedback and can result in improved motivation in cognitive tasks. (PsycINFO Database Record


Assuntos
Neuroimagem Funcional/métodos , Motivação/fisiologia , Neurorretroalimentação/fisiologia , Núcleo Accumbens/fisiologia , Autocontrole , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Núcleo Accumbens/diagnóstico por imagem
13.
Carbohydr Polym ; 181: 1136-1142, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253942

RESUMO

In the present study, cellulose nanofibrils (CNF) were produced from unbleached eucalyptus pulp, and the effect of enzymatic treatment on the properties of CNF was studied. Moreover, the mechanism of enzymatic treatment on the dispersion and film properties of CNF was speculated. The xylanase pretreatment facilitated the deconstruction of pulp into CNF via mechanical shearing and high-pressure homogenization, while the hemicellulose composition was preserved. Compared to the control, the CNF suspensions made from the xylanase pretreated pulp were more crystalline with higher dispersion, optical and rheological properties. CNF films were produced with a vacuum filtration process. The optical and mechanical strength properties of the CNF films were improved by the removal of hemicellulose. It was found that the carboxyl and hydroxyl groups played key roles in affecting the dispersion and film properties of the CNF. The carboxyl group content increased after the enzymatic pretreatment, which benefits the even distribution of CNF in water. The mechanical strength of the CNF films was further improved by exposing the hydroxyl group when lignin-carbohydrate complexes were de-structured by the enzymes. This study expanded the application of CNF produced from unbleached pulp. The theoretical foundation for stabilizing the CNF suspension and the high-speed dehydration of CNF films were explored for the continuous roll to roll production of CNF film.


Assuntos
Celulose/química , Endo-1,4-beta-Xilanases/metabolismo , Nanofibras/química , Fenômenos Ópticos , Reologia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Suspensões , Viscosidade , Difração de Raios X
14.
Psych J ; 5(4): 228-237, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27718340

RESUMO

Minor physical anomalies (MPAs) are subtle signs of fetal developmental abnormalities that have been considered to be among the most replicated risk markers for schizophrenia-spectrum disorders. However, quantitative approaches are needed to measure craniofacial MPAs. The present study adopted an imaging-based quantitative approach to examine craniofacial MPAs across the spectrum of schizophrenia and affective disorders, to address their sensitivity and specificity. We sampled 31 patients with schizophrenia, 30 of their unaffected relatives, and 30 individuals with schizotypal personality traits, as well as 37 non-schizotypal controls. We also examined 17 patients with bipolar disorder and 19 patients with major depressive disorder. Five craniofacial MPAs were measured on anterior-posterior commissure-aligned T1-weighted images of an individual's native brain space: medial-ocular distance, lateral-ocular distance, optical angle, maximum skull length, and skull-base width. Compared to non-schizotypal controls, patients with schizophrenia and their relatives showed a trend toward having smaller optical angles and medial-ocular distance, while no difference was found in patients with bipolar or major depressive disorders, suggesting some degree of specificity to schizophrenia. Our approach may benefit future research on craniofacial MPAs as risk markers for schizophrenia-spectrum disorders, and may eventually be useful in strategies to enhance risk stratification using multiple risk markers.


Assuntos
Transtorno Bipolar/complicações , Anormalidades Craniofaciais/complicações , Transtorno Depressivo Maior/complicações , Esquizofrenia/complicações , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Transtornos do Humor , Adulto Jovem
15.
Psych J ; 5(4): 219-227, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27642716

RESUMO

Multitasking refers to the ability to organize assorted tasks efficiently in a short period of time, which plays an important role in daily life. However, the structural neural correlates of multitasking performance remain unclear. The present study aimed at exploring the brain regions associated with multitasking performance using global correlation analysis. Twenty-six healthy participants first underwent structural brain scans and then performed the modified Six Element Test, which required participants to attempt six subtasks in 10 min while obeying a specific rule. Voxel-based morphometry of the whole brain was used to detect the structural correlates of multitasking ability. Grey matter volume of the anterior cingulate cortex (ACC) was positively correlated with the overall performance and time monitoring in multitasking. In addition, white matter volume of the anterior thalamic radiation (ATR) was also positively correlated with time monitoring during multitasking. Other related brain regions associated with multitasking included the superior frontal gyrus, the inferior occipital gyrus, the lingual gyrus, and the inferior longitudinal fasciculus. No significant correlation was found between grey matter volume of the prefrontal cortex (Brodmann Area 10) and multitasking performance. Using a global correlation analysis to examine various aspects of multitasking performance, this study provided new insights into the structural neural correlates of multitasking ability. In particular, the ACC was identified as an important brain region that played both a general and a specific time-monitoring role in multitasking, extending the role of the ACC from lesioned populations to healthy populations. The present findings also support the view that the ATR may influence multitasking performance by affecting time-monitoring abilities.


Assuntos
Encéfalo/fisiologia , Substância Cinzenta , Imageamento por Ressonância Magnética , Neuroimagem , Desempenho Psicomotor , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Giro do Cíngulo , Humanos , Masculino , Adulto Jovem
16.
Chem Commun (Camb) ; 49(70): 7732-4, 2013 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-23877088

RESUMO

A simple self-assembly platform based on squaraine-embedded CTAB micelles can readily discriminate between Cys and Hcy with different absorption and fluorescence signals. The recognition mechanism is attributed to the fact that analyte adducts trigger the CTAB micelles to undergo sphere-to-rod transition.


Assuntos
Ciclobutanos/química , Cisteína/química , Homocisteína/química , Micelas , Fenóis/química , Cetrimônio , Compostos de Cetrimônio/química , Espectrometria de Fluorescência
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