Metal‐free elemental photocatalysts for hydrogen (H2) evolution are more advantageous than the traditional metal‐based inorganic photocatalysts since the nonmetal elements are generally cheaper, more ...earth‐abundant, and environmentally friendly. Black phosphorus (BP) has been attracting increasing attention in recent years based on its anisotropic 2D layered structure with tunable bandgap in the range of 0.3–2.0 eV; however, the application of BP for photocatalytic H2 evolution has been scarcely reported experimentally although being theoretically predicted. Herein, for the first time, the visible light photocatalytic H2 evolution of BP nanosheets prepared via a facile solid‐state mechanochemical method by ball‐milling bulk BP is reported. Without using any noble metal cocatalyst, the visible light photocatalytic hydrogen evolution rate of BP nanosheets reaches 512 µmol h−1 g−1, which is ≈18 times higher than that of the bulk BP, and is comparable or even higher than that of graphitic carbon nitrides (g‐C3N4).
Black phosphorus (BP) is discovered as the missing metal‐free elemental photocatalyst. Few‐layer BP nanosheets are prepared via a facile solid‐state mechanochemical method, exhibiting a visible light H2 evolution rate of 512 µmol h−1 g−1 without using any noble metal cocatalyst, which is increased by ≈18 times relative to that of bulk BP. Thus the missing photocatalytic property of BP is discovered.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Exfoliated black phosphorus (BP), as a monolayer or few-layer material, has attracted tremendous attention owing to its unique physical properties for applications ranging from optoelectronics to ...photocatalytic hydrogen production. Approaching intrinsic properties has been, however, challenged by chemical reactions and structure degradation of BP under ambient conditions. Surface passivation by capping agents has been proposed to extend the processing time window, yet contamination or structure damage rise challenges for BP applications. Here, we report experiments combined with first-principle calculations that address the degradation chemistry of BP. Our results show that BP reacts with oxygen in water even without light illumination. The reaction follows a pseudo-first-order parallel reaction kinetics, produces PO2 3–, PO3 3–, and PO4 3– with reaction rate constants of 0.019, 0.034, and 0.023 per day, respectively, and occurs preferentially from the P atoms locating at BP edges, which yields structural decay from the nanoflake edges in water. In addition, a negligible decay ratio (0.9 ± 0.3 mol %) and preserved photocatalytic activity of BP are observed after storage in deoxygenated water for 15 days without surface passivation under ambient light. Our results reveal the chemistry of BP degradation and provide a practical approach for exfoliation, delivery, and application of BP.
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IJS, KILJ, NUK, PNG, UL, UM
Abstract
Few-layer black phosphorus (BP) with an anisotropic two-dimensional (2D)-layered structure shows potential applications in photoelectric conversion and photocatalysis, but is easily oxidized ...under ambient condition preferentially at its edge sites. Improving the ambient stability of BP nanosheets has been fulfilled by chemical functionalization, however this functionalization is typically non-selective. Here we show that edge-selective functionalization of BP nanosheets by covalently bonding stable C
60
molecules leads to its significant stability improvement. Owing to the high stability of the hydrophobic C
60
molecule, C
60
functions as a sacrificial shield and effectively protects BP nanosheets from oxidation under ambient condition. C
60
bonding leads to a rapid photoinduced electron transfer from BP to C
60
, affording enhanced photoelectrochemical and photocatalytic activities. The selective passivation of the reactive edge sites of BP nanosheets by sacrificial C
60
molecules paves the way toward ambient processing and applications of BP.
A dynamic STIRPAT model used in the current study is based on panel data from the eight most populous countries from 1975 to 2020, revealing the nonlinear effects of urbanization routes (percentage ...of total urbanization, percentage of small cities and percentage of large cities) on carbon dioxide (CO2) emissions. Using "Dynamic Display Unrelated Regression (DSUR)" and "Fully Modified Ordinary Least Squares (FMOLS)" regressions, the outcomes reflect that percentage of total urbanization and percentage of small cities have an incremental influence on carbon dioxide emissions. However, square percentage of small cities and square percentage of total urbanization have significant adverse effects on carbon dioxide (CO2) emissions. The positive relationship between the percentage of small cities, percentage of total urbanization and CO2 emissions and the negative relationship between the square percentage of small cities, square percentage of total urbanization and CO2 emissions legitimize the inverted U-shaped EKC hypothesis. The impact of the percentage of large cities on carbon dioxide emissions is significantly negative, while the impact of the square percentage of large cities on carbon dioxide emissions is significantly positive, validating a U-shaped EKC hypothesis. The incremental effect of percentage of small cities and percentage of total urbanization on long-term environmental degradation can provide support for ecological modernization theory. Energy intensity, Gross Domestic Product (GDP), industrial growth and transport infrastructure stimulate long-term CO2 emissions. Country-level findings from the AMG estimator support a U-shaped link between the percentage of small cities and CO2 emissions for each country in the entire panel except the United States. In addition, the Dumitrescu and Hulin causality tests yield a two-way causality between emission of carbon dioxide and squared percentage of total urbanization, between the percentage of the large cities and emission of carbon dioxide, and between energy intensity and emission of carbon dioxide. This study proposes renewable energy options and green city-friendly technologies to improve the environmental quality of urban areas.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The usage of flame retardants in flammable polymers has been an effective way to protect both lives and material goods from accidental fires. Phosphorus flame retardants have the potential to be ...follow-on flame retardants after halogenated variants, because of their low toxicity, high efficiency and compatibility. Recently, the emerging allotrope of phosphorus, two-dimensional black phosphorus, as a flame retardant has been developed. To further understand its performance in flame-retardant efficiency among phosphorus flame retardants, in this work, we built model materials to compare the flame-retardant performances of few-layer black phosphorus, red phosphorus nanoparticles, and triphenyl phosphate as flame-retardant additives in cellulose and polyacrylonitrile. Aside from the superior flame retardancy in polyacrylonitrile, few-layer black phosphorus in cellulose showed the superior flame-retardant efficiency in self-extinguishing, ~1.8 and ~4.4 times that of red phosphorus nanoparticles and triphenyl phosphate with similar lateral size and mass load (2.5~4.8 wt%), respectively. The char layer in cellulose coated with the few-layer black phosphorus after combustion was more continuous and smoother than that with red phosphorus nanoparticles, triphenyl phosphate and blank, and the amount of residues of cellulose coated with the few-layer black phosphorus in thermogravimetric analysis were 10 wt%, 14 wt% and 14 wt% more than that with red phosphorus nanoparticles, triphenyl phosphate and blank, respectively. In addition, although exothermic reactions, the combustion enthalpy changes in the few-layer black phosphorus (-127.1 kJ mol
) are one third of that of red phosphorus nanoparticles (-381.3 kJ mol
). Based on a joint thermodynamic, spectroscopic, and microscopic analysis, the superior flame retardancy of the few-layer black phosphorus was attributed to superior combustion reaction suppression from the two-dimensional structure and thermal nature of the few-layer black phosphorus.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In our research, we explored a natural substance called Oxymatrine, found in a traditional Chinese medicinal plant, to fight against a common bird flu virus known as H9N2. This virus not only affects ...birds but can also pose a threat to human health. We focused on how this natural compound can help in stopping the virus from spreading in cells that line the lungs of birds and potentially humans. Our findings show that Oxymatrine can both directly block the virus and boost the body's immune response against it. This dual-action mechanism is particularly interesting because it indicates that Oxymatrine might be a useful tool in developing new ways to prevent and treat this type of bird flu. Understanding how Oxymatrine works against the H9N2 virus could lead to safer and more natural ways to combat viral infections in animals and humans, contributing to the health and well-being of society. The H9N2 Avian Influenza Virus (AIV) is a persistent health threat because of its rapid mutation rate and the limited efficacy of vaccines, underscoring the urgent need for innovative therapies. This study investigated the H9N2 AIV antiviral properties of Oxymatrine (OMT), a compound derived from traditional Chinese medicine, particularly focusing on its interaction with pulmonary microvascular endothelial cells (PMVECs). Employing an array of in vitro assays, including 50% tissue culture infectious dose, Cell Counting Kit-8, reverse transcription-quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blot, we systematically elucidated the multifaceted effects of OMT. OMT dose-dependently inhibited critical antiviral proteins (PKR and Mx1) and modulated the expression of type I interferons and key cytokines (IFN-α, IFN-β, IL-6, and TNF-α), thereby affecting TLR3 signaling and its downstream elements (NF-κB and IRF-3). OMT's antiviral efficacy extended beyond TLR3-mediated responses, suggesting its potential as a versatile antiviral agent. This study not only contributes to the growing body of research on the use of natural compounds as antiviral agents but also underscores the importance of further investigating the broader application of OMT for combating viral infections.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The contribution of women to China’s economic growth and development cannot be overemphasized. Women play important social, economic, and productive roles in any economy. China remains one of the ...countries in the world with severe gender inequality and sex ratio at birth (SRB) imbalance. Severe gender inequality and disenfranchisement of girls with abnormally high sex ratios at birth reflect deep-rooted sexism and adversely affect girls’ development. For China to achieve economic growth, women should not be ignored and marginalized so that they can contribute to the country’s growth, but the sex ratio at birth needs to be lowered because only women can contribute to growth. Thus, this study empirically predicts an asymmetric relationship between gender inequality, sex ratio at birth and economic growth, using NARDL model over the period 1980–2020. The NARDL results show that increases in gender inequality and sex ratio at birth significantly reduce economic growth in both the short and long term, while reductions in gender inequality and sex ratio at birth significantly boost economic growth in both the short and long term. Moreover, the results show the significant contribution of female labor force participation and female education (secondary and higher education) to economic growth. However, infant mortality rate significantly reduced economic growth. Strategically, the study recommends equal opportunities for women in employment, education, health, economics, and politics to reduce gender disparities and thereby promote sustainable economic growth in China. Moreover, policymakers should introduce new population policy to stabilize the sex ratio at birth, thereby promoting China’s long-term economic growth.
Huntington's disease (HD) is one of the most common polyglutamine disorders, leading to progressive dyskinesia, cognitive impairment, and neuropsychological problems. Besides the dysregulation of ...many protein-coding genes in HD, previous studies have revealed a variety of non-coding RNAs that are also dysregulated in HD, including several long non-coding RNAs (lncRNAs). However, an integrated analysis of differentially expressed (DE) genes based on a competing endogenous RNA (ceRNA) network is still currently lacking.
In this study, we have systematically analyzed the gene expression profile data of neural progenitor cells (NPCs) derived from patients with HD and controls (healthy controls and the isogenic controls of HD patient cell lines corrected using a CRISPR-Cas9 approach at the HTT locus) to screen out DE mRNAs and DE lncRNAs and create a ceRNA network. To learn more about the possible functions of lncRNAs in the ceRNA regulatory network in HD, we conducted a functional analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) and established a protein-protein interaction (PPI) network for mRNAs interacting with these lncRNAs.
We identified 490 DE mRNAs and 94 DE lncRNAs, respectively. Of these, 189 mRNAs and 20 lncRNAs were applied to create a ceRNA network. The results showed that the function of DE lncRNAs mainly correlated with transcriptional regulation as demonstrated by GO analysis. Also, KEGG enrichment analysis showed these lncRNAs were involved in tumor necrosis factor, calcium, Wnt, and NF-kappa B signaling pathways. Interestingly, the PPI network revealed that a variety of transcription factors in the ceRNA network interacted with each other, suggesting such lncRNAs may regulate transcription in HD by controlling the expression of such protein-coding genes, especially transcription factors.
Our research provides new clues for uncovering the mechanisms of lncRNAs in HD and can be used as the focus for further investigation.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This study applies the augmented mean group (AMG) estimation technique to investigate whether institutional quality and FDI contribute to economic growth and environmental quality in emerging Asian ...oil-producing and non-oil-producing countries during the period 1975–2020. The estimation of AMG strategy indicates that for every 1% increase in FDI, institutional quality and carbon emissions can significantly boost economic growth by 0.882%, 0.659%, and 0.605%, respectively. Likewise, trade liberalization, transport infrastructure and urbanization can significantly boost economic growth. Long-term variable elasticity coefficients based on carbon emissions model suggest that FDI can stimulate carbon emissions, thereby validating the Pollution Heaven Hypothesis (PHH) in selected panel of countries. Institutional quality has a significant negative impact on carbon emissions, while GDP, trade openness, urbanization, and investment in transport infrastructure contribute significantly to carbon dioxide emissions. Country wise estimates of the AMG strategy show that the institutional quality of oil-producing countries has no significant impact on economic growth, but does boost economic growth in non-oil producing countries. The quality of institutions in both non-oil and oil-producing countries can significantly reduce carbon emissions. FDI stimulates economic growth in oil-producing countries compared to non-oil-producing countries. However, FDI contributes significantly to both oil and non-oil-producing CO2 emissions, thus validating PHH. Controlling factors such as economic growth increase significantly to CO2 emissions in oil-producing countries, while, CO2 emissions from petro-states stimulate more to economic growth than non-petroleum states. The impact of trade liberalization on economic growth is significantly positive in both oil and non-oil-producing countries, but the contribution of non-oil-producing economies is higher than that of oil-producing countries. Compared with non-oil producing countries, trade liberalization in oil-producing countries contributes more to carbon emissions. Investment in transportation infrastructure significantly boosted economic growth in both oil and non-oil producing countries, but oil producing countries contributed more than non-oil producing countries. A range of policy proposals were discussed to achieve economic and environmental sustainability.
Purpose
To examine and compare systemic arterial stiffness responses in humans to acute continuous and interval low-intensity exercise.
Methods
Fifteen healthy young men (21.2 ± 0.4 years) underwent ...non-exercise control (CON), continuous exercise (CE), and interval exercise trial (IE) in a randomized balanced self-control crossover design. Systemic arterial stiffness (Cardio-ankle vascular index, CAVI) was measured at baseline (BL), immediately after (0 min) and 40 min after exercise in CE and IE trials, and at corresponding time points in CON trial. Subjects cycled continuously for 30 min at 35 % heart rate reserve after BL measurement in CE trial, whereas in IE trial, subjects cycled two bouts of 15-min separated by a 20-min rest at the same intensity.
Results
There were no significant CAVI changes with time in CON trial (6.7 ± 0.1, 6.7 ± 0.1, 6.6 ± 0.1 at BL, 0 and 40 min, respectively). In CE trial, CAVI decreased immediately after exercise (0 min) and returned to baseline after 40 min of recovery (6.5 ± 0.1, 5.5 ± 0.2, 6.4 ± 0.1 at BL, 0 and 40 min, respectively). IE elicited similar CAVI reduction from 6.7 ± 0.1 at baseline to 5.6 ± 0.2 at 0 min: however, CAVI at 40 min remained significantly low compared to that of CON trial at corresponding time point (6.0 ± 0.1 vs. 6.6 ± 0.1,
P
< 0.001).
Conclusion
Both acute continuous and interval low-intensity exercise elicits transient improvement in systemic arterial stiffness in humans. Despite equivalent exercise intensity and duration, interval exercise resulted in improved arterial stiffness for longer duration.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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