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1.
Cereb Cortex ; 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35024797

RESUMO

Human decision-making requires the brain to fulfill neural computation of benefit and risk and therewith a selection between options. It remains unclear how value-based neural computation and subsequent brain activity evolve to achieve a final decision and which process is modulated by irrational factors. We adopted a sequential risk-taking task that asked participants to successively decide whether to open a box with potential reward/punishment in an eight-box trial, or not to open. With time-resolved multivariate pattern analyses, we decoded electroencephalography and magnetoencephalography responses to two successive low- and high-risk boxes before open-box action. Referencing the specificity of decoding-accuracy peak to a first-stage processing completion, we set it as the demarcation and dissociated the neural time course of decision-making into valuation and selection stages. The behavioral hierarchical drift diffusion modeling confirmed different information processing in two stages, that is, the valuation stage was related to the drift rate of evidence accumulation, while the selection stage was related to the nondecision time spent in response-producing. We further observed that medial orbitofrontal cortex participated in the valuation stage, while superior frontal gyrus engaged in the selection stage of irrational open-box decisions. Afterward, we revealed that irrational factors influenced decision-making through the selection stage rather than the valuation stage.

2.
Adv Mater ; : e2101339, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34978104

RESUMO

Stretchable electronics incorporating critical sensing, data transmission, display and powering functionalities, is crucial to emerging wearable healthcare applications. To date, methods to achieve stretchability of individual functional devices have been extensively investigated. However, integration strategies of these stretchable devices to achieve all-stretchable systems are still under exploration, in which the reliable stretchable interconnection is a key element. Here, solderless stretchable interconnections based on mechanically interlocking microbridges are developed to realize the assembly of individual stretchable devices onto soft patternable circuits toward multifunctional all-stretchable platforms. This stretchable interconnection can effectively bridge interlayer conductivity with tight adhesion through both conductive microbridges and selectively distributed adhesive polymer. Consequently, enhanced stretchability up to a strain of 35% (R/R0  ≤ 5) is shown, compared with conventional solder-assisted connections which lose electrical conduction at a strain of less than 5% (R/R0  ≈ 30). As a proof of concept, a self-powered all-stretchable data-acquisition platform is fabricated by surface mounting a stretchable strain sensor and a supercapacitor onto a soft circuit through solderless interconnections. This solderless interconnecting strategy for surface-mountable devices can be utilized as a valuable technology for the integration of stretchable devices to achieve all-soft multifunctional systems.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34981914

RESUMO

Stretchable thin-film conductors are basic building blocks in advanced flexible and stretchable electronics. Current research mainly focuses on strategies to improve stretchability and widen the range of applications of stretchable conductors. However, stability should not be neglected, and the electrical failure mode is one of the most common stability issues that determines the current range and duration in a circuit. In this work, we report the electrical failure mechanism of stretchable conductors. We find a special failure mode for the stretchable conductors, which can be attributed to the coupling effect between local thermal strains and dynamic resistance changes of the thin film. This creates a vicious circle that significantly differs from traditional conductors. Physical parameters related to this special failure mode are investigated in detail. It is found that this mechanism is applicable to different kinds of stretchable conductors. Based on this finding, we also explore methods to modulate the failure of stretchable conductors. The failure mechanism found here provides a fundamental understanding of the current effect of stretchable circuits and is crucial for designing stable stretchable bioelectrodes and circuits.

4.
Water Res ; 208: 117880, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837811

RESUMO

Solar-energy-enabled photocatalysis is promising for wastewater treatment. However, due to the changes in the solar position and variable weather conditions, providing optimized light and temperature for photocatalysis under actual weather remains to be a technical difficulty. In this study, a novel Linear fresnel photoreactor (LFP) was firstly developed for wastewater treatment. LFP could achieve effective adjustment of sunlight by flexibly controlling 6 mirrors according to solar position and weather conditions. On sunny condition, LFP could maintain the optimal light irradiance and temperature, while on overcast condition it could provide the highest possible light irradiance and temperature. In the comparative experiments between LFP and Inclined Plate Collector (IPC) (as control reactor) which passively receive sunlight, the Rhodamine B degradation efficiencies in LFP were 2.19 folds, 1.5 folds and 2.28 folds higher than control under the temporarily overcast, totally to slightly overcast and sunny conditions, respectively. In addition, the efficiencies of Amoxicillin degradation and Escherichia coli disinfection in LFP were also 2 folds and 1.37 folds higher than control in sunny conditions, respectively. Furthermore, whole-year estimation indicated that LFP is effective to optimize light irradiance and temperature in typical densely populated areas of the world to achieve high-efficiency wastewater treatment. These results proved that LFP, as an effective solar energy controllable reactor, has great potential in promoting the development of green wastewater treatment infrastructure to improve global public health and achieve eco-friendly society.


Assuntos
Energia Solar , Purificação da Água , Catálise , Desinfecção , Luz Solar , Titânio , Tempo (Meteorologia)
5.
Sci Total Environ ; 806(Pt 2): 150630, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597571

RESUMO

Ozone (O) exposure not only causes lung injury and lung inflammation but also changes blood composition. Previous studies have mainly focused on inflammatory processes and metabolic diseases caused by acute or chronic ozone exposure. However, the effect of ozone on lipid expression profiles remains unclear. This study aimed to investigate the lipidomic changes in lung tissue and serum of rats after ozone exposure for three months and explore the lipid metabolic pathway involved in an ozone-induced injury. Based on the non-targeted lipidomic analysis platform of the UPLC Orbitrap mass spectrometry system, we found that sub-chronic exposure to ozone significantly changed the characteristics of lipid metabolism in lungs and serum of rats. First, the variation in sphingomyelin (SM) and triglyceride (TG) levels in the lung and serum after O3 exposure are shown. SM decreased in both tissues, while TG decreased in the lungs and increased in the serum. Further, the effect of ozone on glycerophospholipids in the lung and serum was completely different. Phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidylinositol (PI) were the major glycerophospholipids whose levels were altered in the lung, while phosphatidylglycerol (PG), phosphatidic acid (PA), and phosphatidylcholine (PC) levels changed dramatically in the serum. Third, after O3 exposure, the level of monogalactosyldiacylglycerol (MGDG), mainly MGDG (43, 11), a saccharolipid, declined significantly and uniquely in the serum. These results suggested that sub-chronic O3 exposure may play a role in the development of several diseases through perturbation of lipidomic profiles in the lungs and blood. In addition, changes in the lipids of the lung and blood may induce or exacerbate respiratory diseases.


Assuntos
Lipidômica , Ozônio , Animais , Lipídeos , Pulmão , Espectrometria de Massas , Ozônio/toxicidade , Ratos
6.
Neuroscience ; 482: 116-131, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34942314

RESUMO

Aquaporins (AQPs) play critical physiological roles in water balance in the central nervous system (CNS). Aquaporin-4 (AQP4), the principal aquaporin expressed in the CNS, has been implicated in the processing of sensory and pain transmission. Akt signaling is also involved in pain mediation, such as neuroinflammatory pain and bone cancer pain. Previously, we found that expression of AQP4 and p-Akt was altered in the rat spinal cord after spinal nerve ligation (SNL). Here, we further investigated the effects of the AQP4 and Akt pathways in the spinal dorsal horn (SDH) on the pathogenesis of neuropathic pain (NP). Spinal AQP4 was significantly upregulated after SNL and was primarily expressed in astrocytes in the SDH. Inhibition of AQP4 with TGN-020 attenuated the development and maintenance of NP by inhibiting glial activation and anti-neuroinflammatory mechanisms. Moreover, inhibition of AQP4 suppressed astrocyte activation both in the SDH and in primary cultures. Similar to AQP4, we found that p-Akt was also significantly elevated after SNL. Inhibition of Akt with MK2206 suppressed AQP4 upregulation and astrocyte activation both in vivo and in vitro. Furthermore, Akt blockade with MK2206 alleviated NP in the early and late phases after SNL. These results elucidate the mechanisms involved in the roles of Akt/AQP4 signaling in the development and maintenance of NP. AQP4 is likely to be a novel therapeutic target for NP management.

7.
Environ Res ; 204(Pt A): 111958, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34478721

RESUMO

There exist two common processes in fishery culture, i.e. antibiotic addition to reduce disease in fishery, and chlorination disinfection to inhibit infectious pathogenic microorganisms. However, antibiotic residues might play important reverse side roles for both aquaculture water pollution and potential formation of chlorination side products. Herein, the transformation behaviour, intermediates analyses and conversion pathway of antibiotic sulfamethoxazole (SMX), and potential generation of halogenated acetic acids (HAAs) in the process of chlorination in fishery water were examined, and the results revealed that the decomposing of SMX satisfied a pseudo first-order kinetic equation. Both the addition of available chlorine and high temperature had affirmative influences on the decontamination of SMX and production of HAAs, and the near-neutral pHs promoted the removal of SMX and generation of HAAs. Br- was favorable for the removal of SMX and yields of brominated acetic acids (Br-AAs). Based on the identified intermediate products, the transformation path of SMX in chlorination process was propounded, to wit, the C-S and S-N bonds in the SMX molecules were firstly cracked, and the primeval intermediate groups are then transformed to form chloroanilines, chlorophenols, etc., and subsequently, chlorophenols were chlorinated and ring-opened to generate toxic HAAs. This study might be meaningful to evaluate the effective removal of sulfonamide antibiotic residues and the potential generation of halogenated DBPs (H-DBPs) when chlorinated in aquaculture water.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Aquicultura , Cloro , Desinfetantes/análise , Desinfecção , Halogenação , Sulfametoxazol , Trialometanos , Água , Poluentes Químicos da Água/análise
8.
Cell Res ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848869

RESUMO

Dopamine (DA) level in the nucleus accumbens (NAc) is critical for reward and aversion encoding. DA released from the ventral mesencephalon (VM) DAergic neurons increases the excitability of VM-projecting D1-dopamine receptor-expressing medium spiny neurons (D1-MSNs) in the NAc to enhance DA release and augment rewards. However, how such a DA positive feedback loop is regulated to maintain DA homeostasis and reward-aversion balance remains elusive. Here we report that the ventral pallidum (VP) projection of NAc D1-MSNs (D1NAc-VP) is inhibited by rewarding stimuli and activated by aversive stimuli. In contrast to the VM projection of D1-MSN (D1NAc-VM), activation of D1NAc-VP projection induces aversion, but not reward. D1NAc-VP MSNs are distinct from the D1NAc-VM MSNs, which exhibit conventional functions of D1-MSNs. Activation of D1NAc-VP projection stimulates VM GABAergic transmission, inhibits VM DAergic neurons, and reduces DA release into the NAc. Thus, D1NAc-VP and D1NAc-VM MSNs cooperatively control NAc dopamine balance and reward-aversion states.

9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6767-6770, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34892661

RESUMO

Electrocardiography (ECG) and Electromyogram (EMG) are widely used to help physicians to diagnose various diseases. Besides, long-term physiological signals monitoring is of great significance for circumstances where certain diseases may not be observed in short-term monitoring. At present, wet electrodes are widely used in the clinic and are considered as a standard method to acquire physiological signals in high fidelity. However, current wet electrodes achieve high-quality signal acquisition by using conductive gel which will dry up as time elapses and finally leads to degradation of the signal quality. Therefore, an anhydrous viscoplastic electrode was proposed in this paper to solve the abovementioned problem. The proposed electrode, which is anhydrous and viscoplastic, enables high quality physiological signal acquisition with firm contact with the skin and it will not dry up within a long period of time. The results showed that the impedance of the proposed viscoplastic electrode could maintain relative stability after two days while that of the gel electrodes would increase significantly due to the gel dried up. Besides, the proposed electrode obtained physiological signals with high quality in both ECG and EMG tasks. After 24 hours of monitoring, the signal quality of the proposed electrode remained unchanged, indicated by the clearly recognizable time-domain signals. However, the signal waveform completely submerged in noise after the gel dried up. Moreover, the superior performance of the viscoplastic electrodes could be confirmed by the SNR difference between the two days, SNR further confirmed the superiority of the, with -2.03±2.10 dB and -3.40±8.27 dB for ECG and EMG respectively, and the SNR difference of gel electrodes were -7.59 ± 5.70 dB and -35.39±15.71 dB respectively. The proposed electrodes could be a great candidate for long-term physiological signal monitoring in risk management of healthcare.Clinical Relevance- The proposed electrode could achieve long-term physiological signals monitoring with high quality.

10.
Addict Biol ; : e13124, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34894025

RESUMO

Missed chance is a powerful factor in shaping risk-taking behaviour. The abnormal risk-taking behaviour is an obvious feature of individuals with Internet gaming disorder (IGD). However, the relationship between the neural responses to missed chance and risk-taking behaviour in IGD individuals remains unclear. In the current fMRI study, 28 IGD subjects (12 female, 23.04 ± 2.43 years old) and 26 healthy control (HC) subjects (13 female, 23.58 ± 2.67 years old) participated in fMRI scanning during performance of a sequential risk-taking task. The general linear model and the psycho-physiological interaction analyses were conducted to explore the difference in neural responses between the two groups. The results showed that IGD subjects reported more regret for the large missed chance and took more risk than HC subjects. Moreover, compared with HC subjects, IGD subjects exhibited greater activations in brain regions like ventral striatum (VS) and superior frontal gyrus (SFG), and stronger VS-thalamus functional connectivity for the large missed chance. Additionally, among IGD subjects, the SFG activation for the large missed chance was positively correlated with the risk-taking behaviour. Together, the results revealed the altered neural responses to missed chance contributed to the risk-taking behaviour in IGD individuals. The findings could help to clearly understand why IGD individuals continue playing online games despite the risks of widely known and could provide a new perspective for the intervention of IGD.

11.
Nat Chem Biol ; 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34934187

RESUMO

The field of engineered living materials aims to construct functional materials with desirable properties of natural living systems. A recent study demonstrated the programmed self-assembly of bacterial populations by engineered adhesion. Here we use this strategy to engineer self-healing living materials with versatile functions. Bacteria displaying outer membrane-anchored nanobody-antigen pairs are cultured separately and, when mixed, adhere to each other to enable processing into functional materials, which we term living assembled material by bacterial adhesion (LAMBA). LAMBA is programmable and can be functionalized with extracellular moieties up to 545 amino acids. Notably, the adhesion between nanobody-antigen pairs in LAMBA leads to fast recovery under stretching or bending. By exploiting this feature, we fabricated wearable LAMBA sensors that can detect bioelectrical or biomechanical signals. Our work establishes a scalable approach to produce genetically editable and self-healable living functional materials that can be applied in biomanufacturing, bioremediation and soft bioelectronics assembly.

12.
J Oncol ; 2021: 3766685, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34961815

RESUMO

Background: IDH mutation is the most common in diffuse LGGs, correlated with a favorable prognosis. However, the IDH-mutant LGGs patients with poor prognoses need to be identified, and the potential mechanism leading to a worse outcome and treatment options needs to be investigated. Methods: A six-gene immune-related prognostic signature in IDH-mutant LGGs was constructed based on two public datasets and univariate, multivariate, and LASSO Cox regression analysis. Patients were divided into low- and high-risk groups based on the median risk score in the training and validation sets. We analyzed enriched pathways and immune cell infiltration, applying the GSEA and the immune evaluation algorithms. Results: Stratification and multivariate Cox analysis unveiled that the six-gene signature was an independent prognostic factor. The signature (0.806/0.795/0.822) showed a remarkable prognostic performance, with 1-, 3-, and 5-year time-dependent AUC, higher than for grade (0.612/0.638/0.649) and 1p19q codeletion status (0.606/0.658/0.676). High-risk patients had higher infiltrating immune cells. However, the specific immune escape was observed in the high-risk group after immune activation, owing to increasing immunosuppressive cells, inhibitory cytokines, and immune checkpoint molecules. Moreover, a novel nomogram model was developed to evaluate the survival in IDH-mutant LGGs patients. Conclusion: The six-gene signature could be a promising prognostic biomarker, which is promising to promote individual therapy and improve the clinical outcomes of IDH-mutant gliomas. The study also refined the current classification system of IDH-mutant gliomas, classifying patients into two subtypes with distinct immunophenotypes and overall survival.

13.
Front Pediatr ; 9: 772138, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34917563

RESUMO

Objectives: To evaluate the causes and risk factors of unplanned surgery after transcatheter closure of ventricular septal defect (VSD) in children. Methods: A total of 773 patients with VSD who had the devices transcatheter released between January 2013 and December 2018 in our institution were retrospectively reviewed. Univariate and multivariate analyses were used to identify the risk factors for unplanned surgery. Results: Twenty four patients (3.1%) underwent unplanned surgery after transcatheter closure of VSD. The most common cause for unplanned surgery was new-onset or worsening aortic regurgitation (14/24; 58.3%), followed by occluder migration (4/24; 16.7%), complete atrioventricular block (2/24; 8.3%), severe hemolysis (2/24; 8.3%), residual shunt (1/24; 4.2%), and occluder edge near the tricuspid valve chordae (1/24; 4.2%). Logistic regression analysis revealed that primary aortic valve prolapse (OR: 5.507, 95%CI: 1.673-18.123, P = 0.005); intracristal VSD (OR: 8.731, 95%CI: 2.274-33.527, P = 0.002); eccentric occluder (OR: 4.191, 95%CI: 1.233-14.246, P = 0.022); larger occluder size (OR: 1.645, 95%CI: 1.331-2.033, P < 0.001); and pulmonary artery systolic pressure ≥45 mmHg (OR: 4.003, 95%CI: 1.073-14.941, P = 0.039) were risk factors for unplanned surgery. Conclusions: New-onset or worsening aortic regurgitation was the primary cause for unplanned surgery after transcatheter closure of VSD in children. Primary aortic valve prolapse, intracristal VSD, eccentric occluder, larger occluder size, pulmonary artery systolic pressure ≥45 mmHg could increase the risk of unplanned surgery.

14.
Brain Behav ; : e2477, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34970857

RESUMO

INTRODCTION: Previous studies have argued that people tend to isolate themselves from negative information. This tendency is modulated by the individual's role in social interaction, that is, as an initiative actor (e.g., "I hit Tom") or a passive recipient (e.g., "Paul hits me"). Depressed patients tend to focus on negative aspects of themselves and cope with situations passively. It is still an open question how the actor/recipient role affects the behavioral and neural responses to self in depression. METHODS: The present study adopted functional magnetic resonance imaging (fMRI) technology to investigate behavioral and neural responses to self (as an actor/recipient) in depressed patients and the matched healthy controls when attributing negative events. RESULTS: Compared with healthy controls, depressed patients showed more self-attribution for negative events. Depressed patients showed increased brain activity in the dorsal medial prefrontal cortex (dmPFC) subsystem of the default mode network (DMN) when they played recipient role in self-related negative events. Activity of the dmPFC subsystem was negatively correlated with depressed patients' self-attribution for negative events in recipient condition. While decreased brain activity in the medial temporal lobe (MTL) subsystem was observed in depressed patients when they played the actor or recipient role in self-related negative events. Activity of the MTL subsystem was negatively correlated with depressed patients' reaction time when they played recipient role in selfrelated negative events. CONCLUSION: These results implicated that depressed patients manifested the negative self-view. Actor/recipient role affected their activation patterns in the DMN which were different from the healthy controls. The correlation between the abnormal brain activations of the DMN and the behavioral performances might manifest more easily when depressed patients played recipient role in negative events.

15.
Brain Res Bull ; 178: 49-56, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34728230

RESUMO

Internet gaming disorder (IGD) has become an increasing mental health issue worldwide. Previous studies indicated that IGD was related to maladaptive risk-taking behavior. However, the relationship among risk-taking behavior, reflection level, and resting-state functional connectivity (rsFC) between brain regions in IGD individuals remains unclear. The current study combined resting-state fMRI and the Devil task to investigate this issue. The behavioral results suggested that IGD participants exhibited increased risk-taking behavior in the Devil task than healthy controls. Moreover, IGD participants' risk-taking behavior was positively correlated with their reflection level. As for fMRI results, IGD participants showed stronger rsFC between orbitofrontal cortex (OFC) and inferior frontal gyrus (IFG) than healthy controls. Additionally, the mediation analyses revealed that, among IGD participants, the rsFC between OFC and IFG fully mediated the relationship between reflection level and risk-taking behavior. Together, the current study highlighted that the altered rsFC between OFC and IFG in IGD individuals modified the relationship between their reflection level and risk-taking behavior, which might contribute to the understanding of neural mechanisms underlying risk-taking behavior in IGD individuals.

16.
Redox Biol ; 48: 102180, 2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34763297

RESUMO

Fine-tuning of osteoclast differentiation (OD) and bone remodeling is crucial for bone homeostasis. Dissecting the mechanisms regulating osteoclastogenesis is fundamental to understanding the pathogenesis of various bone disorders including osteoporosis and arthritis. Nuclear factor erythroid 2-related factor 1 (NFE2L1, also known as NRF1), which belongs to the CNC-bZIP family of transcription factors, orchestrates a variety of physiological processes and stress responses. While Nfe2l1 gene may be transcribed into multiple alternatively spliced isoforms, the biological function of the different isoforms of NFE2L1 in bone metabolism, osteoclastogenesis in particular, has not been reported. Here we demonstrate that knockout of all isoforms of Nfe2l1 transcripts specifically in the myeloid lineage in mice [Nfe2l1(M)-KO] results in increased activity of osteoclasts, decreased bone mass and worsening of osteoporosis induced by ovariectomy and aging. In comparison, LysM-Cre-mediated Nfe2l1 deletion has no significant effect on the osteoblast and osteocytes. Mechanistic investigations using bone marrow cells and RAW 264.7 cells revealed that deficiency of Nfe2l1 leads to accelerated and elevated OD, which is attributed, at least in part, to enhanced accumulation of ROS in the early stage of OD and expression of nuclear factor of activated T cells, cytoplasmic, calcineurin dependent 1α (Nfatc1/α). In addition, NFE2L1 regulates the transcription of multiple antioxidant genes and Nfatc1/α and OD in an isoform-specific manner. While long isoforms of NFE2L1 function as accelerators of induction of Nfatc1/α and antioxidant genes and OD, the short isoform NFE2L1-453 serves as a brake that keeps the long isoforms' accelerator effects in check. These findings provide a novel insight into the regulatory roles of NFE2L1 in osteoclastogenesis and highlight that NFE2L1 is essential in regulating bone remodeling and thus may be a valuable therapeutic target for bone disorders.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34811614

RESUMO

The occurrence of titanium dioxide nanoparticle (TNP), an emerging contaminant, in Taihu Lake of China was investigated. Ti was present at a concentration of 224 ± 59 µg/L in the water samples collected from a water source in east Taihu Lake. Approximately 0.19% of the Ti-containing matter was at the nano-scale. Scanning Electron Microscope analysis verified the existence of Ti-containing components, such as TiOx and FeTiOx. Furthermore, Ti K-edge X-ray absorption near-edge structure spectroscopy was used to detect the phase composition of nano-scaled Ti-containing matter. The spectra showed the three characteristic peaks of TiO2 in the samples, suggesting the occurrence of TNP in Taihu Lake. A least-squares linear combination fitting analysis indicated that the TNP concentration in the water source was ~0.77 µg/L in water and ~0.85 µg/g-dry in sediment. The removal performance of the TNP at a full-scale conventional drinking water treatment plant indicated that ~61% of TNP was removed via coagulation/sediment, sand filtration, and disinfection/clear water reservoir. The coagulation/sediment process accounted for approximately 70% of the total removed TNP. The finished water contained ~ 0.30 µg/L TNP. This study is the first that reported the presence and transport of TNP in a full-scale drinking water treatment system.

19.
Nanomaterials (Basel) ; 11(10)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34684907

RESUMO

The tunnel junction (TJ) is a crucial structure for numerous III-nitride devices. A fundamental challenge for TJ design is to minimize the TJ resistance at high current densities. In this work, we propose the asymmetric p-AlGaN/i-InGaN/n-AlGaN TJ structure for the first time. P-AlGaN/i-InGaN/n-AlGaN TJs were simulated with different Al or In compositions and different InGaN layer thicknesses using TCAD (Technology Computer-Aided Design) software. Trained by these data, we constructed a highly efficient model for TJ resistance prediction using machine learning. The model constructs a tool for real-time prediction of the TJ resistance, and the resistances for 22,254 different TJ structures were predicted. Based on our TJ predictions, the asymmetric TJ structure (p-Al0.7Ga0.3N/i-In0.2Ga0.8N/n-Al0.3Ga0.7N) with higher Al composition in p-layer has seven times lower TJ resistance compared to the prevailing symmetric p-Al0.3Ga0.7N/i-In0.2Ga0.8N/n-Al0.3Ga0.7N TJ. This study paves a new way in III-nitride TJ design for optical and electronic devices.

20.
Ecol Evol ; 11(17): 11874-11889, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34522347

RESUMO

The mechanisms underlying heritable phenotypic divergence associated with adaptation in response to environmental stresses may involve both genetic and epigenetic variations. Several prior studies have revealed even higher levels of epigenetic variation than genetic variation. However, few population-level studies have explored the effects of epigenetic variation on species with high levels of genetic diversity distributed across different habitats. Using AFLP and methylation-sensitive AFLP markers, we tested the hypothesis that epigenetic variation may contribute to differences in plants occupying different habitats when genetic variation alone cannot fully explain adaptation. As a cosmopolitan invasive species, Phragmites australis (common reed) together with high genetic diversity and remarkable adaptability has been suggested as a model for responses to global change and indicators of environmental fluctuations. We found high levels of genetic and epigenetic diversity and significant genetic/epigenetic structure within each of 12 studied populations sampled from four natural habitats of P. australis. Possible adaptive epigenetic variation was suggested by significant correlations between DNA methylation-based epigenetic differentiation and adaptive genetic divergence in populations across the habitats. Meanwhile, various AMOVAs indicated that some epigenetic differences may respond to various local habitats. A partial Mantel test was used to tease out the correlations between genetic/epigenetic variation and habitat after controlling for the correlation between genetic and epigenetic variations. We found that epigenetic diversity was affected mostly by soil nutrient availability, suggesting that at least some epigenetic differentiation occurred independently of genetic variation. We also found stronger correlations between epigenetic variation and phenotypic traits than between genetic variation and such traits. Overall, our findings indicate that genetically based differentiation correlates with heterogeneous habitats, while epigenetic variation plays an important role in ecological differentiation in natural populations of P. australis. In addition, our results suggest that when assessing global change responses of plant species, intraspecific variation needs to be considered.

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