Hydrothermal vs microwave nanoarchitechtonics of carbon dots significantly affects the structure, physicochemical properties, and anti-cancer activity against a specific neuroblastoma cell line.

Carbon dots (CDs) from glucose were synthesized using two of the most common bottom-up methods, namely, microwave assisted (MW) and hydrothermal carbonization (HT). Synthetic parameters such as reaction time, temperature, and precursor concentration were changed to study the effects of each parameter on CD size, structure, surface functionalities, charge, photoluminescence behavior, quantum yield, cytotoxicity, blood-brain barrier (BBB) crossing ability and bioimaging. A detailed analysis is performed to compare the structure and properties of the CDs synthesized in ten different conditions. We show that the synthesis route drastically changes the structure, properties, and related functions of glucose-derived CDs yielding two different subtypes of CDs. Surprisingly, CDs that was synthesized via HT method showed specific anticancer activity against a neuroblastoma cell line while being non-toxic towards healthy cell lines, indicating significant potential for therapeutic applications. CDs synthesized via MW crosses the BBB in zebrafish and rat models, and accumulates in neurons. CDs synthesized via MW method showed high biocompatibility and a great potential to be used for bioimaging applications in vitro and in vivo targeting neurons. Finally, a formation mechanism of CDs is proposed for both HT and MW synthesis routes.

An insight into embryogenesis interruption by carbon nitride dots: can they be nucleobase analogs?

The carbon nitride dot (CND) is an emerging carbon-based nanomaterial. It possesses rich surface functional moieties and a carbon nitride core. Spectroscopic data have demonstrated the analogy between CNDs and cytosine/uracil. Recently, it was found that CNDs could interrupt the normal embryogenesis of zebrafish. Modifying CNDs with various nucleobases, especially cytosine, further decreased embryo viability and increased deformities. Physicochemical property characterization demonstrated that adenine- and cytosine-incorporated CNDs are similar but different from guanine-, thymine- and uracil-incorporated CNDs in many properties, morphology, and structure. To investigate the embryogenesis interruption at the cellular level, bare and different nucleobase-incorporated CNDs were applied to normal and cancerous cell lines. A dose-dependent decline was observed in the viability of normal and cancerous cells incubated with cytosine-incorporated CNDs, which matched results from the zebrafish embryogenesis experiment. In addition, nucleobase-incorporated CNDs were observed to enter cell nuclei, demonstrating a possibility of CND-DNA interactions. CNDs modified by complementary nucleobases could bind each other via hydrogen bonds, which suggests nucleobase-incorporated CNDs can potentially bind the complementary nucleobases in a DNA double helix. Nonetheless, neither bare nor nucleobase-incorporated CNDs were observed to intervene in the amplification of the zebrafish polymerase-alpha 1 gene in quantitative polymerase chain reactions. Thus, in conclusion, the embryogenesis interruption by bare and nucleobase-incorporated CNDs might not be a consequence of CND-DNA interactions during DNA replication. Instead, CND-Ca2+ interactions offer a plausible mechanism that hindered cell proliferation and zebrafish embryogenesis originating from disturbed Ca2+ homeostasis by CNDs. Eventually, the hypothesis that raw or nucleobase-incorporated CNDs can be nucleobase analogs proved to be invalid.

The Blockchain Technology Applied in the Development of Real Economy in Jiangsu under Deep Learning.

This study focuses on the financing difficulties of small and medium enterprises (SMEs) in China to study the application of blockchain technology in developing the real economy. Deep learning neural network is applied to the vulnerability analysis and detection of smart contracts in blockchain technology by analyzing the connotation of blockchain technology and deep learning. A multiparty joint financial service platform based on blockchain technology is established to help SMEs financing institutions reduce transaction costs, thereby helping them reduce loan interest rates. Finally, Jiangsu Province is studied as a pilot unit. The results show that the Recall and F-score of Bidirectional Neural Network for smart contract vulnerability detection are higher than those of the original neural network. The Recall rate and F-score value of the Wide and Deep model are up to 96.2% and 94.7%, which are higher than those of other vulnerability detection schemes. The Timestamp vulnerability has the highest Recall rate, 94.2%, which can rely on a large amount of valid data to improve detection efficiency. The distribution of financing needs of SMEs in Jiangsu Province from 2020 to 2021 shows that the loan number of SMEs is generally not high. Still, financial institutions and enterprises must spend the same transaction cost. After a technology company in Nanjing made a loan through a blockchain financial service platform, its financing cost decreased by 0.5331%. Blockchain technology has played a great role in the financing process of SMEs, reducing intermediate links and credit costs, and promoting the development of SMEs and the real economy.

Synthesis Mechanisms, Structural Models, and Photothermal Therapy Applications of Top-Down Carbon Dots from Carbon Powder, Graphite, Graphene, and Carbon Nanotubes.

In this study, top-down syntheses of carbon dots (CDs) from four different carbon precursors, namely, carbon nano powders, graphite, graphene, and carbon nanotubes, were carried out. Systematic study demonstrated that the optical properties and surface functionalities of the CDs were quite similar and mainly influenced by the synthesis method, while the sizes, morphologies, chemical compositions, and core structures of the CDs were heavily influenced by the carbon precursors. On the basis of these studies, the formation processes and structural models of these four top-down CDs were proposed. The cell cytotoxicity and photothermal conversion efficiency of these CDs were also carefully evaluated, demonstrating their potential applications in photothermal therapy.

Facile and Sensitive Detection of Nitrogen-Containing Organic Bases with Near Infrared C-Dots Derived Assays.

In this article, we have designed both colorimetric (including solution and test paper type) and spectral sensors (including UV-vis and PL type) for the quick and sensitive detection of general nitrogen-containing organic bases (NCOBs); the limit of detection could reach as low as 0.50 nM. NCOBs included 11 examples, covering aliphatic and aromatic amines, five- and six-membered heterocyclics, fused-ring heterocyclics, amino acids, and antibiotics. Furthermore, the assays demonstrated high reliability in sensing NCOBs and excellent ability to distinguish NCOBs from oxygen and sulfur containing organics. The assays developed could find important applications for the detection of NCOBs in the fields of biomedicine, chemistry, and agriculture.

Analyzing enterprise asset structure and profitability using cloud computing and strategic management accounting.

The study expects to further exploring the role of asset structure in enterprise profitability, and analyze the relationship between them in detail. Taking the express industry as the research object, from strategic management accounting, the study uses edge computing and related analysis tools and compares the financial and non-financial indicators of existing express enterprises. The study also discusses the differences between asset structure allocation and sustainable profitability, and constructs the corresponding analysis framework. The results reveal that SF's total assets are obviously large and the profit margin increases. While the total assets of other express enterprises are small, and the express revenue drops sharply. Heavy assets can improve the enterprises' profitability to a certain extent. SF has a good asset management ability. With the support of the capital market, SF's net asset growth ability has been greatly improved. The edge computing method used has higher local data processing ability, and the analysis framework has higher performance than the big data processing method. The study can provide some research ideas and practical value for the asset structure analysis and profitability evaluation of express enterprises.

Gel-like carbon dots: A high-performance future photocatalyst.

To protect water resources, halt waterborne diseases, and prevent future water crises, photocatalytic degradation of water pollutants arouse worldwide interest. However, considering the low degradation efficiency and risk of secondary pollution displayed by most metal-based photocatalysts, highly efficient and environmentally friendly photocatalysts with appropriate band gap, such as carbon dots (CDs), are in urgent demand. In this study, the photocatalytic activity of gel-like CDs (G-CDs) was studied using diverse water pollution models for photocatalytic degradation. The degradation rate constants demonstrated a remarkably enhanced photocatalytic activity of G-CDs compared with most known CD species and comparability to graphitic carbon nitride (g-C3N4). In addition, the rate constant was further improved by 1.4 times through the embedment of g-C3N4 in G-CDs to obtain CD-C3N4. Significantly, the rate constant was also higher than that of g-C3N4 alone, revealing a synergistic effect. Moreover, the use of diverse radical scavengers suggested that the main contributors to the photocatalytic degradation with G-CDs alone were superoxide radicals (O2-) and holes that were, however, substituted by O2- and hydroxyl radicals (OH) due to the addition of g-C3N4. Furthermore, the photocatalytic stabilities of G-CDs and CD-C3N4 turned out to be excellent after four cycles of dye degradation were performed continuously. Eventually, the nontoxicity and environmental friendliness of G-CDs and CD-C3N4 were displayed with sea urchin cytotoxicity tests. Hence, through various characterizations, photocatalytic degradation and cytotoxicity tests, G-CDs proved to be an environmentally friendly and highly efficient future photocatalyst.

[Study on the relationship between iodine status and growth in infants at the key period of brain development].

OBJECTIVE: To investigate the relationship between iodine nutrition and growth/development in infants at the key period of brain development. METHODS: All women from pregnancy to the end of lactation and the weaning infants within 3 years in the Linxia Hui Autonomous Prefecture (Linxia Prefecture) were added iodized oil in 2006 - 2010. In 2006, 2010 one town was randomly selected from each of the five directions (east, south, west, north, central) of each county in Linxia Prefecture. One village was chosen from every town and 20 infants, 20 pregnant women and 20 lactating women were randomly selected in each town. Urinary iodine (UI) of the infants, pregnant and lactating women were determined. DQ value, height and weight of part of infants were measured. According to the above sampling plan, UI of pregnant women, lactating women and infants had been monitored every year after intervention. 0-3 infants were choosing to be control before intervention. RESULTS: UI of 1056 and 2989 0-3 infants were investigated before and after the iodine oil intervention. After the 'iodine oil' intervention, the median UI of infants increased from 107.3 µg/L to 139.6 - 190.7 µg/L, the percentage of UI level that lower than 50 µg/L, decreased from 23.9% to 6.7% - 12.9%. DQ value increased from 92.8 to 104.3, the percentage of normal height and above increased from 65.0% to 82.1% and the percentage of the normal weight and above, increased from 59.3% to 81.4%. The outcomes of DQ value, height and weight showed statistically significant differences, compared to the pre-intervention outcomes (P < 0.05). The median UI of pregnant and lactating women increased from 89.3 µg/L to 118.2 - 187.8 µg/L and from 84.9 µg/L to 135.2 - 187.5 µg/L respectively. CONCLUSION: Infant's growth and development were retarded when iodine deficiency existed at the key period of brain development. Intake of oral iodine oil at key period of brain development could provide adequate nutrition thus improve growth and development on infants.