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1.
Neuroscience ; 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33811940

RESUMO

Opioid use by women during pregnancy has risen dramatically since 2004, accompanied by a striking increase in the prevalence of neonatal opioid withdrawal syndrome and other long-term neurological deficits. However, the effect and mechanisms of prenatal opioid affecting fetal neurodevelopment are largely unknown. To translate from the clinical presentation, we developed a novel mouse model to study the neurodevelopmental consequences of maternal opioid use and management. Female mice were treated with oxycodone before mating to mimic opioid use disorder (OUD) in humans. Following pregnancy confirmation, they were switched to buprenorphine via oral administration, simulating the key medication for OUD (MOUD) employed in clinics to manage OUD in pregnant women. Here, we document critical changes in fetal brain development including reduced cortical thickness, altered corticogenesis, and ventriculomegaly in embryos from dams that were treated with opioids before and throughout pregnancy. Maternal care giving behavior was slightly altered without affecting gross growth of offspring. However, adolescent offspring exposed to maternal opioid use during pregnancy exhibited hyperactivity in late adolescence. Remarkably, we also show increased generation of dopaminergic neurons within the ventral tegmental area of mice exposed to prenatal opioids. These data provide critical evidence of teratogenic effects of opioid use during pregnancy and suggest a causal relationship between maternal opioid use and neurodevelopmental/behavioral anomalies in adolescence.

2.
J Pers Med ; 11(3)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809103

RESUMO

ß-blockers are commonly prescribed to treat cardiovascular disease in hemodialysis patients. Beyond the pharmacological effects, ß-blockers have potential impacts on gut microbiota, but no study has investigated the effect in hemodialysis patients. Hence, we aim to investigate the gut microbiota composition difference between ß-blocker users and nonusers in hemodialysis patients. Fecal samples collected from hemodialysis patients (83 ß-blocker users and 110 nonusers) were determined by 16S ribosomal RNA amplification sequencing. Propensity score (PS) matching was performed to control confounders. The microbial composition differences were analyzed by the linear discriminant analysis effect size, random forest, and zero-inflated Gaussian fit model. The α-diversity (Simpson index) was greater in ß-blocker users with a distinct ß-diversity (Bray-Curtis Index) compared to nonusers in both full and PS-matched cohorts. There was a significant enrichment in the genus Flavonifractor in ß-blocker users compared to nonusers in full and PS-matched cohorts. A similar finding was demonstrated in random forest analysis. In conclusion, hemodialysis patients using ß-blockers had a different gut microbiota composition compared to nonusers. In particular, the Flavonifractor genus was increased with ß-blocker treatment. Our findings highlight the impact of ß-blockers on the gut microbiota in hemodialysis patients.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33821612

RESUMO

A fundamental challenge, particularly, in surface-enhanced Raman scattering (SERS) analysis is the detection of analytes that are distant from the sensing surface. To tackle this challenge, we herein report a long-range SERS (LR-SERS) substrate supporting an extension of electric field afforded by long-range surface plasmon resonance (LRSPR) excited in symmetrical dielectric environments. The LR-SERS substrate has a sandwich configuration with a triangle-shaped gold nanohole array embedded between two dielectrics with similar refractive indices (i.e., MgF2 and water). The finite-difference time-domain simulation was applied to guide the design of the LR-SERS substrate, which was engineered to have a wavelength-matched LRSPR with 785 nm excitation. The simulations predict that the LR-SERS substrate exhibits great SERS enhancement at distances of more than 10 nm beyond its top surface, and the enhancement factor (EF) has been improved by three orders of magnitude on LR-SERS substrates compared to that on conventional substrates. The experimental results show good agreement with the simulations, an EF of 4.1 × 105 remains available at 22 nm above the LR-SERS substrate surface. The LR-SERS substrate was further applied as a sensing platform to detect microRNA (miRNA) let-7a coupled with a hybridization chain reaction (HCR) strategy. The developed sensor displays a wide linear range from 10 aM to 1 nM and an ultralow detection limit of 8.5 aM, making it the most sensitive among the current detection strategies for miRNAs based on the SERS-HCR combination to the best of our knowledge.

4.
Int J Med Mushrooms ; 23(4): 59-69, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33822508

RESUMO

This study used a He-Ne laser with pulsed light irradiation to produce mutant strains of Phellinus igniarius strain JQ9 with enhanced characteristics for fermentation (17.685 ± 3.092 g/L) compared with the parent strain (12.062 ± 1.119 g/L). The combined treatment conditions were as follows: He-Ne laser irradiation for 30 min using a spot diameter of 10 mm, pulsed light treatment power set at 100 J, a treatment distance of 14.5 cm, and a flash frequency of 0.5 s. The production of bioactive polysaccharides and small biocompounds such as polyphenols, flavonoids, and triterpenes increased together with mycelium production. The results showed that polyphenol content was significantly correlated with L*, a*, and b* values (R = -0.594, P < 0.01; R = 0.571, P < 0.01; and R = 0.500, P < 0.05; respectively). Antagonistic and random amplified polymorphic DNA analyses indicated that the genetic material of the screened mutants was altered. The mutant screening using a He-Ne laser with pulsed light irradiation could be an effective method for the development of Phellinus strains and could thus improve mycelium production.

5.
Neural Regen Res ; 16(11): 2234-2242, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33818507

RESUMO

Metformin, a first-line drug for type-2 diabetes, has been shown to improve locomotor recovery after spinal cord injury. However, there are studies reporting no beneficial effect. Recently, we found that high dose of metformin (200 mg/kg, intraperitoneal) and acute phase administration (immediately after injury) led to increased mortality and limited locomotor function recovery. Consequently, we used a lower dose (100 mg/kg, i.p.) metformin in mice, and compared the effect of immediate administration after spinal cord injury (acute phase) with that of administration at 3 days post-injury (subacute phase). Our data showed that metformin treatment starting at the subacute phase significantly improved mouse locomotor function evaluated by Basso Mouse Scale (BMS) scoring. Immunohistochemical studies also revealed significant inhibitions of microglia/macrophage activation and astrogliosis at the lesion site. Furthermore, metformin treatment at the subacute phase reduced neutrophil infiltration. These changes were in parallel with the increased survival rate of spinal neurons in animals treated with metformin. These findings suggest that low-dose metformin treatment for subacute spinal cord injury can effectively improve the functional recovery possibly through anti-inflammation and neuroprotection. This study was approved by the Institute Animal Care and Use Committee at the University of Texas Medical Branch (approval No. 1008041C) in 2010.

6.
Curr Opin Genet Dev ; 69: 103-111, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33780743

RESUMO

Birds are the most diversified terrestrial vertebrates due to highly diverse integumentary organs that enable robust adaptability to various eco-spaces. Here we show that this complexity is built upon multi-level regional specifications. Across-the-body (macro-) specification includes the evolution of beaks and feathers as new integumentary organs that are formed with regional specificity. Within-an-organ (micro-) specification involves further modifications of organ shapes. We review recent progress in elucidating the molecular mechanisms underlying feather diversification as an example. (1) ß-Keratin gene clusters are regulated by typical enhancers or high order chromatin looping to achieve macro- and micro-level regional specification, respectively. (2) Multi-level symmetry-breaking of feather branches confers new functional forms. (3) Complex color patterns are produced by combinations of macro-patterning and micro-patterning processes. The integration of these findings provides new insights toward the principle of making a robustly adaptive bio-interface.

7.
Nat Commun ; 12(1): 1570, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33692357

RESUMO

The ULK complex initiates the autophagosome formation, and has recently been implicated in selective autophagy by interacting with autophagy receptors through its FIP200 subunit. However, the structural mechanism underlying the interactions of autophagy receptors with FIP200 and the relevant regulatory mechanism remain elusive. Here, we discover that the interactions of FIP200 Claw domain with autophagy receptors CCPG1 and Optineurin can be regulated by the phosphorylation in their respective FIP200-binding regions. We determine the crystal structures of FIP200 Claw in complex with the phosphorylated CCPG1 and Optineurin, and elucidate the detailed molecular mechanism governing the interactions of FIP200 Claw with CCPG1 and Optineurin as well as their potential regulations by kinase-mediated phosphorylation. In addition, we define the consensus FIP200 Claw-binding motif, and find other autophagy receptors that contain this motif within their conventional LC3-interacting regions. In all, our findings uncover a general and phosphoregulatable binding mode shared by many autophagy receptors to interact with FIP200 Claw for autophagosome biogenesis, and are valuable for further understanding the molecular mechanism of selective autophagy.

8.
Plant Dis ; 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33779251

RESUMO

Starting from the May to August 2020 (average humidity 76.6% and temperature 25.2°C in Taipei), Boston ivy (Parthenocissus tricuspidata) plants on the campus of National Taiwan University (25°01'05.4"N 121°32'36.6"E) exhibited leaf rusts caused by Phakopsora ampelopsidis (Tzean et al., 2019) and leaf spots caused by an unknown pathogen. The leaf spots appeared reddish to brown color and mostly irregular to round shape on the simple and trifoliate leaflets (Supplemental Figure 1A-C). The leaf spots were surface-disinfected with 1% NaOCl for 30 seconds, and the margin of healthy and infected tissues was cut and placed onto water agar, which were incubated at room temperature. Hyphae grown out from leaf spots were sub-cultured on potato dextrose agar (PDA), and the majority of isolates exhibited white colony with black pycnidial conidiomata embedded in PDA. The pycnidial conidiomata of two-week-old has an average diameter of 463±193 µm (n=30) and the sizes of α-conidia were 5.71±0.49 µm in length and 2.42±0.32 µm in width (n=50) similar to the previous records (Crous et al. 2015). The α-conidium was one-celled, hyaline, and ovoid with two droplets (Supplemental Figure 1D-G). This putative pathogen was re-inoculated to confirm its pathogenicity on the leaves of Boston ivy plants. A PDA block with actively growing fungal edge was placed on the tiny needle-wounded leaves of detached branches (Supplemental Figure H-I) and the whole plants in pots (Supplemental Figure 1J-M) in a moist chamber at 28°C in dark. Reddish to brown leaf spots were observed by 2 days post-inoculation (dpi) and the leaf spots expanded by 5 dpi. To complete the Koch's postulates, the pathogen was re-isolated from inoculated leaves and the re-isolated pathogen exhibited identical morphology to the original isolate. The internal transcribed spacer (ITS), translational elongation factor subunit 1-α gene (EF1α), ß-tubulin (BT), and calmodulin (CAL) was amplified using the primers ITS1/ITS4 (Martin and Rygiewicz. 2005), EF1-728F/EF1-986R, Bt2a/Bt2b, and CAL-228F/CAL-737R, respectively (Manawasinghe et al. 2019). Using BLAST in the NCBI database, the ITS (MT974186), EF1α (MT982963), and ß-tubulin (MT982962) sequences showed 98.57% (NR_147574.1, 553 out of 561 bp), 98.04% (KR936133.1, 350 out of 357 bp), and 99.23% (KR936132.1, 518 out of 522 bp) identity to the Diaporthe tulliensis ex-type BRIP 62248a, respectively (Dissanayake et al. 2017). Phylogenetic analysis using concatenated sequences of ITS, EF1α, and ß-tubulin grouped the D. tulliensis isolated from Boston ivy leaf spots with the D. tulliensis ex-type (Supplemental Figure 1N). In summary, the morphological and molecular characterizations supported the causal pathogen of Boston ivy leaf spot as D. tulliensis. While Diaporthe ampelopsidis was reported to infect Parthenocissus quinquefolia and P. tricuspidata (Anonymous, 1960; Wehmeyer, 1933), there is no record for D. tulliensis infecting Boston ivy according to the USDA National Fungus Collections (Farr and Rossman. 2020). Because pathogens of Boston ivy such as P. ampelopsidis may also infect close-related crops like grape (Vitis vinifera L.) and D. tulliensis has been known to infect kiwifruits (Actinidia chinensis) and cocoa (Theobroma cacao) (Bai et al. 2016; Yang et al. 2018), the emergence of D. tulliensis should be aware to avoid potential damage to economic crops.

9.
Clin Kidney J ; 14(3): 983-990, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33779636

RESUMO

Background: Despite widespread use, there is no trial evidence to inform ß-blocker's (BB) relative safety and efficacy among patients undergoing hemodialysis (HD). We herein compare health outcomes associated with carvedilol or bisoprolol use, the most commonly prescribed BBs in these patients. Methods: We created a cohort study of 9305 HD patients who initiated bisoprolol and 11 171 HD patients who initiated carvedilol treatment between 2004 and 2011. We compared the risk of all-cause mortality and major adverse cardiovascular events (MACEs) between carvedilol and bisoprolol users during a 2-year follow-up. Results: Bisoprolol initiators were younger, had shorter dialysis vintage, were women, had common comorbidities of hypertension and hyperlipidemia and were receiving statins and antiplatelets, but they had less heart failure and digoxin prescriptions than carvedilol initiators. During our observations, 1555 deaths and 5167 MACEs were recorded. In the multivariable-adjusted Cox model, bisoprolol initiation was associated with a lower all-cause mortality {hazard ratio [HR] 0.66 [95% confidence interval (CI) 0.60-0.73]} compared with carvedilol initiation. After accounting for the competing risk of death, bisoprolol use (versus carvedilol) was associated with a lower risk of MACEs [HR 0.85 (95% CI 0.80-0.91)] and attributed to a lower risk of heart failure [HR 0.83 (95% CI 0.77-0.91)] and ischemic stroke [HR 0.84 (95% CI 0.72-0.97)], but not to differences in the risk of acute myocardial infarction [HR 1.03 (95% CI 0.93-1.15)]. Results were confirmed in propensity score matching analyses, stratified analyses and analyses that considered prescribed dosages or censored patients discontinuing or switching BBs. Conclusions: Relative to carvedilol, bisoprolol initiation by HD patients was associated with a lower 2-year risk of death and MACEs, mainly attributed to lower heart failure and ischemic stroke risk.

10.
NPJ Biofilms Microbiomes ; 7(1): 20, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658514

RESUMO

Little is known about the relationship between gut dysbiosis, inflammation, and adverse outcomes in patients with chronic kidney disease. We examined the association of microbial diversity with all-cause mortality in hemodialysis patients. The gut microbiota was assessed by 16S ribosomal RNA gene sequencing. During a median follow-up of 2.1 years, the adjusted risk of death among patients with higher diversity (above median) was 74% lower than that among patients with lower diversity (below median). We then compared the microbial composition between nonsurvivors and survivors in a matched case-control study. We observed significantly lower microbial diversity and higher proinflammatory cytokines among nonsurvivors than survivors. Specifically, the relative abundance of Succinivibrio and Anaerostipes, two short-chain fatty acid-producing bacteria, was markedly reduced in nonsurvivors. Thus, a unique gut microbial composition is associated with an increased risk of mortality among hemodialysis patients and may be used to identify subjects with a poor prognosis.

11.
PLoS Negl Trop Dis ; 15(3): e0009183, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33657175

RESUMO

Global Zika virus (ZIKV) outbreaks and their strong link to microcephaly have raised major public health concerns. ZIKV has been reported to affect the innate immune responses in neural stem/progenitor cells (NS/PCs). However, it is unclear how these immune factors affect neurogenesis. In this study, we used Asian-American lineage ZIKV strain PRVABC59 to infect primary human NS/PCs originally derived from fetal brains. We found that ZIKV overactivated key molecules in the innate immune pathways to impair neurogenesis in a cell stage-dependent manner. Inhibiting the overactivated innate immune responses ameliorated ZIKV-induced neurogenesis reduction. This study thus suggests that orchestrating the host innate immune responses in NS/PCs after ZIKV infection could be promising therapeutic approach to attenuate ZIKV-associated neuropathology.

12.
Nature ; 591(7849): 288-292, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33658715

RESUMO

The evolutionarily conserved target of rapamycin (TOR) kinase acts as a master regulator that coordinates cell proliferation and growth by integrating nutrient, energy, hormone and stress signals in all eukaryotes1,2. Research has focused mainly on TOR-regulated translation, but how TOR orchestrates the global transcriptional network remains unclear. Here we identify ethylene-insensitive protein 2 (EIN2), a central integrator3-5 that shuttles between the cytoplasm and the nucleus, as a direct substrate of TOR in Arabidopsis thaliana. Glucose-activated TOR kinase directly phosphorylates EIN2 to prevent its nuclear localization. Notably, the rapid global transcriptional reprogramming that is directed by glucose-TOR signalling is largely compromised in the ein2-5 mutant, and EIN2 negatively regulates the expression of a wide range of target genes of glucose-activated TOR that are involved in DNA replication, cell wall and lipid synthesis and various secondary metabolic pathways. Chemical, cellular and genetic analyses reveal that cell elongation and proliferation processes that are controlled by the glucose-TOR-EIN2 axis are decoupled from canonical ethylene-CTR1-EIN2 signalling, and mediated by different phosphorylation sites. Our findings reveal a molecular mechanism by which a central signalling hub is shared but differentially modulated by diverse signalling pathways using distinct phosphorylation codes that can be specified by upstream protein kinases.

13.
Anal Cell Pathol (Amst) ; 2021: 8842105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33688464

RESUMO

This study analyzed and compared the potential role of fatty acid metabolism pathways in three subtypes of renal cell carcinoma. Biological pathways that were abnormally up- and downregulated were identified through gene set variation analysis in the subtypes. Abnormal downregulation of the fatty acid metabolism pathway occurred in all three renal cell carcinoma subtypes. Alteration of the fatty acid metabolism pathway was vital in the development of pan-renal cell carcinoma. Bioinformatics methods were used to obtain a panoramic view of copy number variation, single-nucleotide variation, mRNA expression, and the survival landscape of fatty acid metabolism pathway-related genes in pan-renal cell carcinoma. Most importantly, we used genes related to the fatty acid metabolism pathway to establish a prognostic-related risk model in the three subtypes of renal cell carcinoma. The data will be valuable for future clinical treatment and scientific research.

14.
G3 (Bethesda) ; 11(2)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33704432

RESUMO

The Crest mutation in chicken shows incomplete dominance and causes a spectacular phenotype in which the small feathers normally present on the head are replaced by much larger feathers normally present only in dorsal skin. Using whole-genome sequencing, we show that the crest phenotype is caused by a 197 bp duplication of an evolutionarily conserved sequence located in the intron of HOXC10 on chromosome 33. A diagnostic test showed that the duplication was present in all 54 crested chickens representing eight breeds and absent from all 433 non-crested chickens representing 214 populations. The mutation causes ectopic expression of at least five closely linked HOXC genes, including HOXC10, in cranial skin of crested chickens. The result is consistent with the interpretation that the crest feathers are caused by an altered body region identity. The upregulated HOXC gene expression is expanded to skull tissue of Polish chickens showing a large crest often associated with cerebral hernia, but not in Silkie chickens characterized by a small crest, both homozygous for the duplication. Thus, the 197 bp duplication is required for the development of a large crest and susceptibility to cerebral hernia because only crested chicken show this malformation. However, this mutation is not sufficient to cause herniation because this malformation is not present in breeds with a small crest, like Silkie chickens.

15.
Hematology ; 26(1): 312-320, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33706667

RESUMO

OBJECTIVES: The present meta-analysis was performed to evaluate the efficacy, toxicities of both hypomethylating agents (decitabine and azaciticine) in the treatment of CMML patients. METHODS: All available cohort studies of patients with CMML treated with decitabine and azacitidine were identified. The primary endpoints of this meta-analysis were response to hypomethylating agents. Pooled estimates of treatment response and drug-related adverse events were calculated using fixed or random effect models. RESULTS: Fourteen studies with 600 CMML patients (decitabine: n=196; azacitidine: n=404) were identified and included for meta-analysis. HMAs yielded a pooled ORR estimate of 43% (95% CI: 36%-50%) in patients with CMML. Patients received either azacitidine or decitabine exhibited comparable incidence of ORR (43% vs. 45%, P=0.810), while significantly higher incidence of mCR was observed in patients treated with decitabine (23% vs. 10%, P=0.000). Decitabine treatment was also associated with higher incidence of transfusion independence (42% vs. 20%, P=0.044). Both HMAs led to objective hematologic or non-hematologic AEs (27%-43%), while dosage modification/delay were more frequent in patients treated with azacitidine (81% vs. 67%, P=0.021). CONCLUSION: This current study may provide preliminary data in evaluating the efficacy and safety of HMAs in patients with CMML. Decitabine and azacitidine are comparable effective and safe in treating CMML. However, it is necessary to point out that any comparison of decitabine and azacitidine with respect to clinical outcomes can only be done in the context of a randomized controlled trial.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33683143

RESUMO

Calonectria ilicicola (ana. Cylindrocladium parasiticum) is a soilborne plant pathogenic fungus with a broad host range, and it can cause red crown rot of soybean and Cylindrocladium black rot of peanut, which has become an emerging threat to crop production worldwide. Limited molecular studies have focused on Calonectria ilicicola and one of the possible difficulties is the lack of genomic resource. This study presents the first high quality and near-completed genome of C. ilicicola using the Oxford Nanopore GridION sequencing platform. A total of 16 contigs were assembled and the genome of C. ilicicola isolate F018 was estimated to have 11 chromosomes. Currently, the C. ilicicola F018 genome represents the most contiguous assembly, which has the lowest contig number and the highest contig N50 among all Calonectria genome resources. Putative protein-coding sequences and secretory proteins were estimated to be 17,308 and 1,930 in the C. ilicicola F018 genome, respectively; and the prediction was close to other plant pathogenic fungi such as Fusarium species within the Nectriaceae family. The availability of this high-quality genome resource is expected to facilitate research on fungal biology and genetics of C. ilicicola, and to support the understanding on pathogen virulence and disease management.

17.
Cell Metab ; 33(3): 565-580.e7, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33657393

RESUMO

Stimulation of adipose tissue thermogenesis is regarded as a promising avenue in the treatment of obesity. However, pharmacologic engagement of this process has proven difficult. Using the Connectivity Map (CMap) approach, we identified the phytochemical hyperforin (HPF) as an anti-obesity agent. We found that HPF efficiently promoted thermogenesis by stimulating AMPK and PGC-1α via a Ucp1-dependent pathway. Using LiP-SMap (limited proteolysis-mass spectrometry) combined with a microscale thermophoresis assay and molecular docking analysis, we confirmed dihydrolipoamide S-acetyltransferase (Dlat) as a direct molecular target of HPF. Ablation of Dlat significantly attenuated HPF-mediated adipose tissue browning both in vitro and in vivo. Furthermore, genome-wide association study analysis indicated that a variation in DLAT is significantly associated with obesity in humans. These findings suggest that HPF is a promising lead compound in the pursuit of a pharmacological approach to promote energy expenditure in the treatment of obesity.

18.
J Hazard Mater ; 415: 125604, 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33725555

RESUMO

The ongoing use of ZnO nanoparticles (NPs)-associated commercial products results in large release of ZnO NPs into soils and has prompted systematic investigation regarding their fractionation and fate in soils. To date, little information is available about the long-term dissolution and transformation of ZnO NPs in different soils. The distribution and speciation of Zn in two different soils (i.e., Red soil (RS) and Wushantu soil (WS)) treated with either ZnO NPs or bulk ZnO were elucidated by combining soil incubation study with synchrotron-based techniques. Results revealed that ZnO NPs and bulk ZnO were almost dissolved after 1 day, indicating their rapid dissolution upon entering RS (pH-acidic). Rapid dissolution of ZnO NPs was also observed even in WS (pH- circumneutral). The solubilized Zn2+ released from ZnO particles was completely transformed into stable forms (e.g., Zn-Al LDH, Zn-OM, and Zn(OH)2) and Zn-Al LDH was the dominant species in WS after incubation for 360 days. A majority of solubilized Zn2+ released from ZnO particles was also transformed into Zn-Al LDH precipitate in RS. The findings of this study facilitate a better understanding of the fate of ZnO in soils, which could be leveraged for remediation of ZnO-polluted soils.

19.
J Affect Disord ; 286: 220-227, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33740639

RESUMO

BACKGROUND: COVID-19 is still spreading worldwide and posing a threat to individuals' physical and mental health including problematic internet use (PIU). A potentially high-risk group for PIU are those with symptoms of attention deficit and hyperactivity (ADHD symptoms), because of restrictions in their physical activity levels and engagement in computer diversions requiring only short attention spans. METHODS: We used convenience sampling in a cross-sectional survey of university students from 30 universities in Wuhan, Hubei Province, China. We assessed PIU using the Internet Addiction Test and ADHD symptoms using the WHO Adult ADHD Self-Report Screening Scale. Using logistic regression and linear regression analyses we adjusted for demographic, epidemic-related and psychological covariates in models of the association between ADHD symptoms and PIU. RESULTS: Among 11,254 participants, we found a 28.4% (95% CI, 27.5%-29.2%) prevalence of PIU, relatively higher than before the pandemic. In our final logistic regression model, participants with ADHD symptoms had approximately two times the risk for PIU (OR: 2.31, 95% CI: 1.89-2.83). Similarly, individuals with depression, anxiety, insomnia, PTSD symptoms and feeling stress during the pandemic had a higher risk of PIU, while those exercising regularly during the pandemic had a lower risk. LIMITATIONS: The cross-sectional design and reliance on internet based self-reports for ADHD symptoms and PIU assessments, without direct structured interviews for validation, are limitations. CONCLUSIONS: The prevalence of PIU was high during COVID-19, and those people with ADHD symptoms and other mental illness symptoms appear to be at higher risk of PIU. Regular exercise may reduce that PIU risk and hence should be recommended during the COVID-19 pandemic.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33784645

RESUMO

The MnN monolayer with square-octagon structure (so-MnN) is explored using density functional calculations. The results show that the so-MnN monolayer is energetically, dynamically, thermally and mechanically stable, and exhibits the ferromagnetism and intrinsic half-metallicity. The total magnetic moment is 16 µB in unit cell (Mn4N4). The energy band of spin-up crosses the Fermi level while the spin-down channel has semiconductor characteristic with a direct band gap of 3.0 eV at Γ-point. By applying the biaxial strain, the band gap in spin-down channel can be tuned. And the so-MnN monolayer still possesses the characteristic of ferromagnetism and intrinsic half-metallicity. Finally, the Curie temperature TC increases gradually under biaxial strains from 0 to +3%, while the TC has a decreasing trend under the biaxial strains from 0 to -3%.

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