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1.
Proc Natl Acad Sci U S A ; 120(45): e2205463120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37917793

RESUMO

Zero-knowledge proof (ZKP) is a fundamental cryptographic primitive that allows a prover to convince a verifier of the validity of a statement without leaking any further information. As an efficient variant of ZKP, noninteractive zero-knowledge proof (NIZKP) adopting the Fiat-Shamir heuristic is essential to a wide spectrum of applications, such as federated learning, blockchain, and social networks. However, the heuristic is typically built upon the random oracle model that makes ideal assumptions about hash functions, which does not hold in reality and thus undermines the security of the protocol. Here, we present a quantum solution to the problem. Instead of resorting to a random oracle model, we implement a quantum randomness service. This service generates random numbers certified by the loophole-free Bell test and delivers them with postquantum cryptography (PQC) authentication. By employing this service, we conceive and implement NIZKP of the three-coloring problem. By bridging together three prominent research themes, quantum nonlocality, PQC, and ZKP, we anticipate this work to inspire more innovative applications that combine quantum information science and the cryptography field.

2.
Small ; : e2304894, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546002

RESUMO

Superhydrophobic fabrics with multiple functions have become a research hotspot. However, it is challenging to make self-healing mechanically robust and eco-friendly superhydrophobic fabrics, which are limited by complex fabrication processes and excessive use of environmentally unfriendly solvents during fabrication. Herein, inspired by the secretion of a waxy substance from the surface of lotus leaves to restore water repellency, self-healing superhydrophobic composite fabrics (as-synthesized PA66/6-PET@Tico) are obtained by constructing a papillary TiO2 and tentacle-like fluorinated acrylate polymer (FCB015) coating on polyester-nylon composite fabrics using two-step hydrothermal method. The result indicates that PA66/6-PET@Tico with hierarchical micro/nanostructure exhibits excellent superhydrophobic and self-healing properties. Compared with FCB015 coated fabric, the contact angles (CA) of water and soybean oil rise to 172.2° and 166.8° from 137.4° and 98.8°, respectively. After mechanical abrasion, PA66/6-PET@Tico recovers a water contact angle (WCA) of 165.6° at room temperature. The WCA remains higher than 155° after 18 h of chemical corrosion. Furthermore, the bacterial inhibition rates of PA66/6-PET@Tico for Staphylococcus Aureus and Escherichia Coli are 99.90 and 98.38%, respectively. In this work, a new idea is proposed for designing a simple and effective self-healing superhydrophobic coating, expecting to promote the large-scale industrial production and application of functional surfaces.

3.
Org Biomol Chem ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39034644

RESUMO

An efficient and environmentally friendly electrochemical oxidative selective halogenation of pyrazolones has been developed under conditions free of metals, external oxidants, and external supporting electrolytes. The reaction demonstrates good functional group tolerance and maintains high efficiency in large-scale synthesis, yielding moderate to excellent yields of the desired 4-halopyrazolones. This method provides a green and convenient route for the direct installation of a halogen moiety into bioactive pyrazolone derivatives, which can be utilized in a myriad of applications.

4.
Nature ; 562(7728): 548-551, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30287887

RESUMO

Randomness is important for many information processing applications, including numerical modelling and cryptography1,2. Device-independent quantum random-number generation (DIQRNG)3,4 based on the loophole-free violation of a Bell inequality produces genuine, unpredictable randomness without requiring any assumptions about the inner workings of the devices, and is therefore an ultimate goal in the field of quantum information science5-7. Previously reported experimental demonstrations of DIQRNG8,9 were not provably secure against the most general adversaries or did not close the 'locality' loophole of the Bell test. Here we present DIQRNG that is secure against quantum and classical adversaries10-12. We use state-of-the-art quantum optical technology to create, modulate and detect entangled photon pairs, achieving an efficiency of more than 78 per cent from creation to detection at a distance of about 200 metres that greatly exceeds the threshold for closing the 'detection' loophole of the Bell test. By independently and randomly choosing the base settings for measuring the entangled photon pairs and by ensuring space-like separation between the measurement events, we also satisfy the no-signalling condition and close the 'locality' loophole of the Bell test, thus enabling the realization of the loophole-free violation of a Bell inequality. This, along with a high-voltage, high-repetition-rate Pockels cell modulation set-up, allows us to accumulate sufficient data in the experimental time to extract genuine quantum randomness that is secure against the most general adversaries. By applying a large (137.90 gigabits × 62.469 megabits) Toeplitz-matrix hashing technique, we obtain 6.2469 × 107 quantum-certified random bits in 96 hours with a total failure probability (of producing a random number that is not guaranteed to be perfectly secure) of less than 10-5. Our demonstration is a crucial step towards transforming DIQRNG from a concept to a key aspect of practical applications that require high levels of security and thus genuine randomness7. Our work may also help to improve our understanding of the origin of randomness from a fundamental perspective.

5.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396734

RESUMO

Dioscorea alata L. (Dioscoreaceae) is a widely cultivated tuber crop with variations in tuber color, offering potential value as health-promoting foods. This study focused on the comparison of D. alata tubers possessing two distinct colors, white and purple, to explore the underlying mechanisms of color variation. Flavonoids, a group of polyphenols known to influence plant color and exhibit antioxidant properties, were of particular interest. The total phenol and total flavonoid analyses revealed that purple tubers (PTs) have a significantly higher content of these metabolites than white tubers (WTs) and a higher antioxidant activity than WTs, suggesting potential health benefits of PT D. alata. The transcriptome analysis identified 108 differentially expressed genes associated with the flavonoid synthesis pathway, with 57 genes up-regulated in PTs, including CHS, CHI, DFR, FLS, F3H, F3'5'H, LAR, ANS, and ANR. The metabolomics analysis demonstrated that 424 metabolites, including 104 flavonoids and 8 tannins, accumulated differentially in PTs and WTs. Notably, five of the top ten up-regulated metabolites were flavonoids, including 6-hydroxykaempferol-7-O-glucoside, pinocembrin-7-O-(6″-O-malonyl)glucoside, 6-hydroxykaempferol-3,7,6-O-triglycoside, 6-hydroxykaempferol-7-O-triglycoside, and cyanidin-3-O-(6″-O-feruloyl)sophoroside-5-O-glucoside, with the latter being a precursor to anthocyanin synthesis. Integrating transcriptome and metabolomics data revealed that the 57 genes regulated 20 metabolites within the flavonoid synthesis pathway, potentially influencing the tubers' color variation. The high polyphenol content and antioxidant activity of PTs indicate their suitability as nutritious and health-promoting food sources. Taken together, the findings of this study provide insights into the molecular basis of tuber color variation in D. alata and underscore the potential applications of purple tubers in the food industry and human health promotion. The findings contribute to the understanding of flavonoid biosynthesis and pigment accumulation in D. alata tubers, opening avenues for future research on enhancing the nutritional quality of D. alata cultivars.


Assuntos
Dioscorea , Transcriptoma , Humanos , Dioscorea/genética , Dioscorea/metabolismo , Antioxidantes , Antocianinas/metabolismo , Flavonoides , Perfilação da Expressão Gênica , Metabolômica , Glucosídeos , Cor , Regulação da Expressão Gênica de Plantas
6.
J Environ Manage ; 331: 117278, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36634423

RESUMO

Methane production through anaerobic digestion (AD) of municipal sludge is economic and eco-friendly, which is commonly affected by temperature and pollutants residues. However, little is known about methanogenesis in psychrophilic AD (PAD) with temperature variations that simulating seasonal variations and with antibiotic stress. Here, two groups of AD systems with oxytetracycline (OTC) were operated with temperature maintained at 35 °C and 15 °C or variation to explore the influence to methanogenesis. The acetic acid was noticeably accumulated in OTC groups initially (P < 0.001). Methane production was noticeably inhibited initially in PAD with OTC, but had been stimulated later at 35 °C. The dominant acetoclastic methanogens Methanosaeta gradually decreased to 15.48% and was replaced by methylotrophic Methanomethylovorans (73.43%) in PAD with OTC. Correspondingly, the abundances of functional genes related to methylotrophic methanogenesis were also higher in these groups. Besides, genes involving in methane oxidation had over 50 times higher abundances in PAD with OTC groups in the second phase. Further investigation is essential to understand the main dynamics of methanogenesis in PAD and to clear the related molecular mechanism for future methane production regulation in sludge systems.


Assuntos
Oxitetraciclina , Esgotos , Esgotos/química , Antibacterianos , Anaerobiose , Reatores Biológicos , Metano
7.
Phys Rev Lett ; 129(5): 050502, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35960585

RESUMO

The security of quantum key distribution (QKD) usually relies on that the users' devices are well characterized according to the security models made in the security proofs. In contrast, device-independent QKD-an entanglement-based protocol-permits the security even without any knowledge of the underlying quantum devices. Despite its beauty in theory, device-independent QKD is elusive to realize with current technologies. Especially in photonic implementations, the requirements for detection efficiency are far beyond the performance of any reported device-independent experiments. In this Letter, we report a proof-of-principle experiment of device-independent QKD based on a photonic setup in the asymptotic limit. On the theoretical side, we enhance the loss tolerance for real device imperfections by combining different approaches, namely, random postselection, noisy preprocessing, and developed numerical methods to estimate the key rate via the von Neumann entropy. On the experimental side, we develop a high-quality polarization-entangled photon source achieving a state-of-the-art (heralded) detection efficiency about 87.5%. Although our experiment does not include random basis switching, the achieved efficiency outperforms previous photonic experiments involving loophole-free Bell tests. Together, we show that the measured quantum correlations are strong enough to ensure a positive key rate under the fiber length up to 220 m. Our photonic platform can generate entangled photons at a high rate and in the telecom wavelength, which is desirable for high-speed generation over long distances. The results present an important step toward a full demonstration of photonic device-independent QKD.

8.
J Nat Prod ; 85(6): 1634-1640, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35671109

RESUMO

The first total synthesis of coryaurone A, which was originally obtained from Psoralea corylifolia L., was achieved via an efficient route with the longest linear sequence of six steps from the commercially available 6-hydroxy-2H-benzofuran-3-one in 37% overall yield. A series of representative analogues were synthesized from the same starting material in 4-7 steps with overall yields of 27-56%. The cytotoxicities of these compounds against the leukemia cell line HL-60 and the colon cancer cell line SW480 were determined. Among them, compounds 12, 14, 21, and 27 exhibited different levels of cytotoxic activity, which were greater than the positive control cisplatin.


Assuntos
Antineoplásicos , Psoralea , Antineoplásicos/farmacologia
9.
Environ Res ; 210: 112880, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35123970

RESUMO

Chlorinated antimicrobial triclocarban (3,4,4'-trichlorocarbanilide, TCC) is an emerging refractory contaminant omnipresent in various environments. Preferential microbial hydrolysis of TCC to chloroanilines is essential for its efficient mineralization. However, the microbial mineralization of TCC in domestic wastewater is poorly understood. Here, the bioelectrochemical catabolism of TCC to chloroanilines (3,4-dichloroaniline and 4-chloroaniline) and then to CO2 was realized through the cascade acclimation of TCC-hydrolyzing and chloroanilines-oxidizing microbial communities. The biodegradation of chloroanilines was obviously enhanced in the bioelectrochemical reactors. Pseudomonas, Diaphorobacter, and Sphingomonas were the enriched TCC or chloroanilines degraders in the bioelectrochemical reactors. The addition of TCC enhanced the synergistic effect within functional microbial communities based on the feature of the phylogenetic ecological networks. This study provides a new idea for the targeted domestication and construction of functionally differentiated microbial communities to efficiently remove TCC from domestic wastewater through a green and low-carbon bioelectrochemical method.


Assuntos
Microbiota , Águas Residuárias , Aclimatação , Carbanilidas , Oxirredução , Filogenia
10.
Foodborne Pathog Dis ; 19(3): 179-191, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35020482

RESUMO

Giardia duodenalis has a wide range of host species and is a common causative agent of diarrheal disease in humans and animals. This study conducted a systematic review and meta-analysis to evaluate the pooled prevalence of Giardia among dogs in China. We extracted 33 studies related to the prevalence of G. duodenalis in dogs, with samples taken from 2001 to 2021. The random-effect model was used to calculate pooled prevalence estimates with 95% confidence intervals, and the analyzed data were from 14 provinces in China. The estimated overall prevalence of G. duodenalis among dogs in China was 11.2%. The prevalence of Giardia was significantly higher in Northwestern China (35.7%) than in other regions. The prevalence in 2010 or later (11.8%) was significantly higher than in 2010 or before (6.9%). The estimated prevalence detected by microscopy (9.3%) was lower than molecular (12.3%) and serological (14.3%) ones. The prevalence was higher in dogs <1 year of age (12.2%) than that >1 year (5.4%). Among the genotype groups, the positive rate of assemblage A (5.2%) was significantly higher than that of other assemblages. Depending on the dog' type, the prevalence of G. duodenalis in stray dogs (3.5%) was lower than that in pet dogs (6.7%) and intensively breeding dogs (11.8%). In addition, no correlation was found between Giardia positive rate and the dogs' gender (p > 0.05). We also analyzed the effects of different geographic factor subgroups (longitude, latitude, precipitation, temperature, humidity, and altitude) on the prevalence of G. duodenalis in dogs in China. The results showed that giardiasis was widespread in dogs in China. It is suggested that corresponding control scheme and effective management measures should be formulated and applied to reduce the transmission of G. duodenalis according to the difference in geographical conditions in different areas.


Assuntos
Giardia lamblia , Giardíase , Animais , China/epidemiologia , Cães , Fezes , Genótipo , Giardia lamblia/genética , Giardíase/epidemiologia , Giardíase/veterinária , Prevalência
11.
Br J Cancer ; 125(6): 865-876, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34274945

RESUMO

BACKGROUND: Many molecular alterations are shared by embryonic liver development and hepatocellular carcinoma (HCC). Identifying the common molecular events would provide a novel prognostic biomarker and therapeutic target for HCC. METHODS: Expression levels and clinical relevancies of SLC38A4 and HMGCS2 were investigated by qRT-PCR, western blot, TCGA and GEO datasets. The biological roles of SLC38A4 were investigated by functional assays. The downstream signalling pathway of SLC38A4 was investigated by qRT-PCR, western blot, immunofluorescence, luciferase reporter assay, TCGA and GEO datasets. RESULTS: SLC38A4 silencing was identified as an oncofetal molecular event. DNA hypermethylation contributed to the downregulations of Slc38a4/SLC38A4 in the foetal liver and HCC. Low expression of SLC38A4 was associated with poor prognosis of HCC patients. Functional assays demonstrated that SLC38A4 depletion promoted HCC cellular proliferation, stemness and migration, and inhibited HCC cellular apoptosis in vitro, and further repressed HCC tumorigenesis in vivo. HMGCS2 was identified as a critical downstream target of SLC38A4. SLC38A4 increased HMGCS2 expression via upregulating AXIN1 and repressing Wnt/ß-catenin/MYC axis. Functional rescue assays showed that HMGCS2 overexpression reversed the oncogenic roles of SLC38A4 depletion in HCC. CONCLUSIONS: SLC38A4 downregulation was identified as a novel oncofetal event, and SLC38A4 was identified as a novel tumour suppressor in HCC.


Assuntos
Sistema A de Transporte de Aminoácidos/genética , Sistema A de Transporte de Aminoácidos/metabolismo , Carcinoma Hepatocelular/patologia , Regulação para Baixo , Hidroximetilglutaril-CoA Sintase/metabolismo , Neoplasias Hepáticas/patologia , Fígado/embriologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Transplante de Neoplasias , Prognóstico , Proteínas Proto-Oncogênicas c-myc/metabolismo , Via de Sinalização Wnt
12.
Phys Rev Lett ; 126(5): 050503, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33605771

RESUMO

Randomness expansion where one generates a longer sequence of random numbers from a short one is viable in quantum mechanics but not allowed classically. Device-independent quantum randomness expansion provides a randomness resource of the highest security level. Here, we report the first experimental realization of device-independent quantum randomness expansion secure against quantum side information established through quantum probability estimation. We generate 5.47×10^{8} quantum-proof random bits while consuming 4.39×10^{8} bits of entropy, expanding our store of randomness by 1.08×10^{8} bits at a latency of about 13.1 h, with a total soundness error 4.6×10^{-10}. Device-independent quantum randomness expansion not only enriches our understanding of randomness but also sets a solid base to bring quantum-certifiable random bits into realistic applications.

13.
BMC Ophthalmol ; 21(1): 427, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893049

RESUMO

PURPOSE: To study whether retinal pigment epithelium (RPE) disruption and choroidal hyper-transmission on spectral-domain optical coherence tomography (SD-OCT) are signs of inflammatory neovascularization (CNV) in punctate inner choroidopathy (PIC). METHODS: This is a prospective cohort study. Seventeen patients (18 eyes) were diagnosed as PIC without CNV at baseline. Changes of morphological characteristics including choroidal hyper-transmission, hypo-transmission, RPE disruption, and ellipsoid zone (EZ) damage on SD-OCT were observed and recorded at baseline, 4, 8 and 12 weeks, respectively. The occurrence of CNV was detected by OCTA at each visit. Fisher's exact test was used to compare the relationship with each morphological sign and evaluate the predictable capability of secondary CNV in PIC (PIC+CNV) based on the structure changes on OCT. RESULTS: Among the 18 eyes, a total of 5 eyes (27.8%) developed PIC+CNV subsequently within 4 weeks follow-up. At 4, 8 and 12 weeks of follow-up, RPE disruption and choroidal hyper-transmission were found in all 5 PIC+CNV eyes. The incidence of RPE disruption was significant higher in PIC+CNV eyes compared with PIC eyes (P=0.001). PIC eyes with hyper-transmission had a higher risk for developing CNV compared with those without hyper-transmission (P=1.17×10-3). 2 out of 5 PIC+CNV eyes had a choroidal hypo-transmission component adjacent to hyper-transmission zone at 4 weeks of follow-up, and hypo-transmission could be observed in all 5 PIC+CNV eyes at 8 weeks of follow-up. The incidence of choroidal hypo-transmission was significant higher in PIC+CNV eyes than PIC eyes after 8 weeks. EZ damage began to recover at 4 weeks of follow-up and had no significant difference in the PIC eyes and PIC+CNV eyes (P=0.150, 0.196, 0.353). CONCLUSION: The presence of choroidal hyper-transmission and RPE disruption on SD-OCT is associated with the PIC+CNV. SD-OCT imaging facilitates the differentiation and track of the progression of inflammatory lesions and secondary CNV in PIC.


Assuntos
Epitélio Pigmentado da Retina , Síndrome dos Pontos Brancos , Corioide , Humanos , Estudos Prospectivos , Tomografia de Coerência Óptica
14.
Mikrochim Acta ; 188(8): 255, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264390

RESUMO

As an extremely important post-transcriptional regulator, miRNAs are involved in a variety of crucial biological processes, and the abnormal expressions of miRNAs are closely related to a variety of diseases. In this work, for the first time, we designed a nucleic acid lock nanostructure for specific detection of miRNA-21, which changes the self-structure to "active conformation" by binding the target, in order to generate triggers to initiate the subsequent reaction. Emphatically, this flexible nucleic acid lock is capable of self-cleaving without the assistance of external component, overcoming the disadvantages of the complex design and requiring protease assistance in traditional nanostructure. Moreover, the combination of DNAzyme and RCA technology not only greatly improves the efficiency of signal amplification but also enables primer generation to simultaneous cascade RCA amplification. Additionally, the electrochemical detection technology based on silver nanoclusters overcomes the shortcomings of traditional detection methods such as low sensitivity and complex operation. The detection limit achieved was 9.3 aM with a wide dynamic response ranging from 10 aM to 100 pM (at the DPV peak of - 0.5 V), which is comparable to most of the reported studies. Therefore, our work provided an ultra-sensitive way for the detection of miRNAs using nanostructures and revealed an effective means for disease theranostics and cancer diagnosis. In this work, for the first time, we designed a nucleic acid lock nanostructure based on its self-structural transformation for the specific detection of miRNA. And the combination of DNAzyme and cascade RCA reaction greatly improved the signal amplification efficiency.


Assuntos
DNA Catalítico/química , DNA/química , MicroRNAs/química , Sequência de Bases , Técnicas Biossensoriais , Técnicas Eletroquímicas , Células HeLa , Humanos , Limite de Detecção , Células MCF-7 , Nanopartículas Metálicas/química , Técnicas de Amplificação de Ácido Nucleico , Prata/química
15.
J Cell Mol Med ; 24(1): 238-249, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31680444

RESUMO

Long noncoding RNA (lncRNA) has been suggested to play an important role in a variety of diseases over the past decade. In a previous study, we identified a novel lncRNA, termed HOXA11-AS, which was significantly up-regulated in calcium oxalate (CaOx) nephrolithiasis. However, the biological function of HOXA11-AS in CaOx nephrolithiasis remains poorly defined. Here, we demonstrated that HOXA11-AS was significantly up-regulated in CaOx nephrolithiasis both in vivo and in vitro. Gain-/loss-of-function studies revealed that HOXA11-AS inhibited proliferation, promoted apoptosis and aggravated cellular damage in HK-2 cells exposed to calcium oxalate monohydrate (COM). Further investigations showed that HOXA11-AS regulated monocyte chemotactic protein 1 (MCP-1) expression in HK-2 cell model of CaOx nephrolithiasis. In addition, online bioinformatics analysis and dual-luciferase reporter assay results showed that miR-124-3p directly bound to HOXA11-AS and the 3'UTR of MCP-1. Furthermore, rescue experiment results revealed that HOXA11-AS functioned as a competing endogenous RNA to regulate MCP-1 expression through sponging miR-124-3p and that overexpression of miR-124-3p restored the inhibitory effect of proliferation, promotion effects of apoptosis and cell damage induced by HOXA11-AS overexpression. Taken together, HOXA11-AS mediated CaOx crystal-induced renal inflammation via the miR-124-3p/MCP-1 axis, and this outcome may provide a good potential therapeutic target for nephrolithiasis.


Assuntos
Oxalato de Cálcio/toxicidade , Quimiocina CCL2/metabolismo , Inflamação/genética , Rim/patologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Sequência de Bases , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cristalização , Técnicas de Silenciamento de Genes , Humanos , Inflamação/patologia , Rim/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Nefrolitíase/genética , RNA Longo não Codificante/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
16.
J Environ Manage ; 242: 403-414, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31059953

RESUMO

The objective of this study is to synthesize previous research findings from bioretention experiments and identify design features that lead to the best performance of bioretention pollutant removal with a data-driven approach. A bioretention database was built from 79 bioretention publications, composed of 182 records of bioretention cells with their design features and the corresponding pollutant removal efficiency data. Non-parametric correlation analysis, multiple linear regression (MLR), and decision tree classifiers were applied to investigate the relationships between bioretention design features and pollutant removal efficiencies. Non-parametric statistics and MLR results indicated that bioretention surface area, media depth, the presence of an internal water storage (IWS) layer, soil composition, and vegetation cover are all significantly correlated with pollutant removal efficiencies. The impacts of design features are significantly different under different climate and inflow conditions. Decision tree classifiers showed that non-vegetated bioretention cells with sand filter media generally have higher than 80% total suspended solid (TSS) mass removal efficiencies; bioretention cells with minimum organic matter and greater than 0.58 m soil media depth tend to remove more than 51% of total nitrogen (TN); and vegetated bioretention cells with minimum organic matter remove more than 67% of total phosphorus (TP). The overall accuracy of decision tree classifiers in the test set is around 70% to predict TSS, TN, and TP mass removal efficiency classes. This study suggests that the data-driven approach provides insights into understanding the complex relationship between bioretention design features and pollutant removal performance.


Assuntos
Poluentes Ambientais , Fósforo , Nitrogênio , Chuva , Solo
17.
J Environ Manage ; 236: 365-379, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30739042

RESUMO

Low impact development (LID) has been increasingly practiced since its emergence in the 1990s. Although the hydrological benefits of LIDs have been extensively documented, the climate impact on LID performance remains unclear with increasing variations in spatial and temporal climate patterns. This systematic review contributes to providing a structured summary of research on how LID systems are sensitive to climate variability by empirical and hypothetical research approaches. The selected 46 peer-reviewed journal articles published between 2003 and 2017 were analyzed by key variables, including climatic factors, LID types, and hydrologic measures used to quantify LID performance. A conceptual framework formulated in this study synthesizes the relationship between climate and LID effectiveness. The results of weighted meta-analysis reveal a greater sensitivity of runoff volume to changing storm frequency than peak discharge rates, while the capacity of LID systems to reduce both volume and peak discharge rates diminishes with increasing storm intensity. Future explorations of the sensitivity of LIDs to climate fluctuations will help strategize LID installation for targeted storm patterns and flood mitigation goals. To enhance existing methods and make a balance between empirical and hypothetical knowledge, this study suggests future directions of research and encourages development of effective stormwater management policy.


Assuntos
Modelos Teóricos , Chuva , Clima , Inundações , Hidrologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-29581121

RESUMO

Group A Streptococcus (GAS) is an important human pathogen that causes a wide spectrum of diseases, including necrotizing fasciitis and streptococcal toxic shock syndrome. Dextromethorphan (DM), an antitussive drug, has been demonstrated to efficiently reduce inflammatory responses, thereby contributing to an increased survival rate of GAS-infected mice. However, the anti-inflammatory mechanisms underlying DM treatment in GAS infection remain unclear. DM is known to exert neuroprotective effects through an NADPH oxidase-dependent regulated process. In the present study, membrane translocation of NADPH oxidase subunit p47phox and subsequent reactive oxygen species (ROS) generation induced by GAS infection were significantly inhibited via DM treatment in RAW264.7 murine macrophage cells. Further determination of proinflammatory mediators revealed that DM effectively suppressed inducible nitric oxide synthase (iNOS) expression and NO, tumor necrosis factor alpha, and interleukin-6 generation in GAS-infected RAW264.7 cells as well as in air-pouch-infiltrating cells from GAS/DM-treated mice. GAS infection caused AKT dephosphorylation, glycogen synthase kinase-3ß (GSK-3ß) activation, and subsequent NF-κB nuclear translocation, which were also markedly inhibited by treatment with DM and an NADPH oxidase inhibitor, diphenylene iodonium. These results suggest that DM attenuates GAS infection-induced overactive inflammation by inhibiting NADPH oxidase-mediated ROS production that leads to downregulation of the GSK-3ß/NF-κB/NO signaling pathway.


Assuntos
Dextrometorfano/uso terapêutico , Óxido Nítrico Sintase Tipo II/metabolismo , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/enzimologia , Animais , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Oniocompostos/farmacologia , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Infecções Estreptocócicas/metabolismo , Células THP-1
19.
Phys Rev Lett ; 121(8): 080404, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30192594

RESUMO

Inspired by the recent remarkable progress in the experimental test of local realism, we report here such a test that achieves an efficiency greater than (78%)^{2} for entangled photon pairs separated by 183 m. Further utilizing the randomness in cosmic photons from pairs of stars on the opposite sides of the sky for the measurement setting choices, we not only close the locality and detection loopholes simultaneously, but also test the null hypothesis against local hidden variable mechanisms for events that took place 11 years ago (13 orders of magnitude longer than previous experiments). After considering the bias in measurement setting choices, we obtain an upper bound on the p value of 7.87×10^{-4}, which clearly indicates the rejection with high confidence of potential local hidden variable models. One may further push the time constraint on local hidden variable mechanisms deep into the cosmic history by taking advantage of the randomness in photon emissions from quasars with large aperture telescopes.

20.
Phys Rev Lett ; 120(1): 010503, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29350962

RESUMO

Quantum mechanics provides the means of generating genuine randomness that is impossible with deterministic classical processes. Remarkably, the unpredictability of randomness can be certified in a manner that is independent of implementation devices. Here, we present an experimental study of device-independent quantum random number generation based on a detection-loophole-free Bell test with entangled photons. In the randomness analysis, without the independent identical distribution assumption, we consider the worst case scenario that the adversary launches the most powerful attacks against the quantum adversary. After considering statistical fluctuations and applying an 80 Gb×45.6 Mb Toeplitz matrix hashing, we achieve a final random bit rate of 114 bits/s, with a failure probability less than 10^{-5}. This marks a critical step towards realistic applications in cryptography and fundamental physics tests.

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