Search

The rapid growth of household photovoltaics poses a significant challenge to the safe operation of distribution networks. To enable the unified monitoring of household photovoltaic inverters by power grid companies, this paper introduces an information interaction device for household photovoltaic inverters based on high-speed power line carrier communication and high-speed radio frequency communication. The study begins by analyzing the information access architecture of the household photovoltaic inverter, followed by a presentation of the hardware and software design of the information interaction device. Subsequent experiments conducted at various photovoltaic stations demonstrate an impressive 98% success rate for information interaction, highlighting the device’s robust reliability.

Aspect-level sentiment analysis is a research focal point for natural language comprehension. An attention mechanism is a very important approach for aspect-level sentiment analysis, but it only fuses sentences from a semantic perspective and ignores grammatical information in the sentences. Graph convolutional networks (GCNs) are a better method for processing syntactic information; however, they still face problems in effectively combining semantic and syntactic information. This paper presents a sentiment-supported graph convolutional network (SSGCN). This SSGCN first obtains the semantic information of the text through aspect-aware attention and self-attention; then, a grammar mask matrix and a GCN are applied to preliminarily combine semantic information with grammatical information. Afterward, the processing of these information features is divided into three steps. To begin with, features related to the semantics and grammatical features of aspect words are extracted. The second step obtains the enhanced features of the semantic and grammatical information through sentiment support words. Finally, it concatenates the two features, thus enhancing the effectiveness of the attention mechanism formed from the combination of semantic and grammatical information. The experimental results show that compared with benchmark models, the SSGCN had an improved accuracy of 6.33–0.5%. In macro F1 evaluation, its improvement range was 11.68–0.5%. [ABSTRACT FROM AUTHOR]

The exploration of optimizing content knowledge representation and enhancing critical thinking capabilities in English as Foreign Language (EFL) learners' writing still needs to be improved. Cultivating adept critical thinking skills and effective content knowledge representation is paramount for EFL learners, given its correlation with heightened writing proficiency. This study sought to examine critical thinking skills as a mediator in the correlation between strategies of content knowledge representation and writing proficiency among EFL learners. A total of 360 English as foreign language participants engaged in the California Critical Thinking Skills Test and responded to a questionnaire on strategies of content knowledge representation conducted at Kaifeng Science Technology and Communication College, China. Subsequently, participants undertook a writing task, and the outcomes underwent analysis using SPSS 26.0, incorporating descriptive analysis, correlational analysis, and AMOS 24.0 for mediating analysis. The findings unveiled a correlation between critical thinking skills and EFL learners' writing proficiency, echoing the association observed between content knowledge representation strategies and writing proficiency. Furthermore, critical thinking skills were identified as a mediator, linking content knowledge representation strategies to writing proficiency among EFL learners. The combination of content knowledge representation and critical thinking skills emerged as a positive role in the writing process. This research underscored the paramount significance of critical thinking skills within a specialized discipline, highlighting their transformative potential for EFL learners' writing competency and accentuating their functions in the broader writing pedagogy. [ABSTRACT FROM AUTHOR]

This study explores the significance of mobile phone usage in English language learning among students at the National University of Modern Languages. By administering an open-ended questionnaire to a sample of 100 Pakistani students enrolled in Advanced English for the Master of English program, the research investigates how smartphones are used, the attitudes and behaviors of students, and the challenges encountered in utilizing mobile technology within the learning environment. The findings demonstrate that smartphones play a crucial role in enhancing students' English language learning, as most participants express a positive view regarding their use in language instruction. This research presents a novel teaching approach for ESL students, underscoring the importance of a robust pedagogical foundation and appropriate training. Additionally, the study suggests the need for further exploration through experimental studies to examine the efficacy of smartphones in English language learning. The outcomes of this study contribute to a comprehensive understanding of the effective integration of mobile technology in ESL education, providing valuable insights for educators and researchers in the field. [ABSTRACT FROM AUTHOR]

With advances in nanotechnology, various new drug delivery systems (DDSs) have emerged and played a key role in the diagnosis and treatment of cancers. Over the last two decades, gold nanocages (AuNCs) have been attracting considerable attention because of their outstanding properties. This review summarizes current advancements in endogenous, exogenous, and dual/multi-stimuli responsive AuNCs in drug delivery. This review focuses on the properties, clinical translation potential, and limitations of stimuli-responsive AuNCs for cancer diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Background: Following myocardial infarction (MI), a series of structural and functional changes evolves in the myocardium, collectively defined as cardiac remodeling.Purpose: The aim of present study was to investigate the cardioprotection of salvianolicacid B (SalB) and ginsenoside Rg1 (Rg1) combination against cardiac remodeling in a rat model at the subacute phase of MI and further elucidate the underlying mechanism.Methods: Rat heart was exposed via a left thoracotomy at the fourth intercostal space and MI was induced by a ligature below the left descending coronary artery. Hemodynamic assay was conducted using a Mikro-tipped SPR-320 catheter which was inserted through the right carotid artery into left ventricle.Myocardial infarct size was detected using 3,5-triphenyltetrazolium chloride (TTC) staining. Haematoxylin and eosin (HE) stain and picric sirius red stain were conducted for histopathological detection. Immunohistochemistry was used to detect the expression of α-smooth muscle actin (α-SMA) and gelatin zymography was used to evaluate the activities of matrix metalloproteinase-9 (MMP-9).Results: Comparing with MI rats, 30 mg/kg SalB-Rg1 improved cardiac function verified by maximum rate of pressure development for contraction (+dp/dtmax, p < 0.01) and maximum rate of pressure development for relaxation (-dp/dtmax, p < 0.05); reduced myocardial infarct size (p < 0.05) verified by TTC staining, improved cardiac structure based on HE stain; decreased collagen volume fraction (p < 0.05) and collagen I/III ratio (p < 0.05) according picrosirius red staining. The underlying mechanism of SalB-Rg1 against cardiac remodeling was associated with its down-regulation on α-SMA expression according immunohistochemistry (p < 0.01) and inhibition on MMP-9 activity based on in-gel zymography (p < 0.05).Conclusion: All above study indicated the potential therapeutic effects of SalB-Rg1 on heart. [ABSTRACT FROM AUTHOR]

A combination of different therapy strategies has great potential to efficaciously treat malignant tumors, by virtue of their synergetic effects. Herein, a co-delivery system based on gold nanocages (AuNCs) was designed to deliver both doxorubicin (DOX) and microRNA-122 mimic (miR-122) for an enhanced cancer therapy. DOX was loaded into the AuNCs and miR-122 was condensed onto the surface of the functionalized AuNCs by an electrostatic interaction. Polyethyleneglycol (PEG) and hyaluronic acid (HA) were also introduced to the co-delivery system for targeted drug delivery. We evaluated the cellular uptake, biodistribution and anti-tumor effect in vitro and in vivo. Our results demonstrated an effective delivery of DOX and miR-122 into tumor cells and the tumor tissue. Importantly, the triple therapy, namely the combination of chemotherapy, gene therapy and photothermal therapy, mediated by this multifunctional drug delivery system, exhibited better anti-tumor effect than any single therapy, both in vitro and in vivo. Additionally, this drug delivery system caused insignificant toxicity to the major organs and had no obvious effect on the body weight of the mice. It could be concluded that multifunctional AuNCs are promising as a co-delivery vector for an enhanced anti-tumor effect. [ABSTRACT FROM AUTHOR]

Therapeutic strategies based on modulation of microRNAs (miRNAs) activity hold much promise for cancer therapy, but for clinical applications, the efficient delivery of miRNAs to tumor cells or tumor tissues remains a great challenge. In this work, microRNA-181b inhibitor (anti-miR-181b) is successfully condensed into polyethyleneimine (PEI)-modified and folate receptor (FR)-targeted PEGylated gold nanocages (AuNCs). This delivery system is designated as anti-miR-181b/PTPAuNCs nanocomplexes (PTPAuNC-NPs), which begin with chemical modification of AuNCs with SH-PEG5000-folic acid (SH-PEG5000-FA) and SH-PEG5000 through a gold-sulfur bond, followed by conjugating PEI using lipoic acid as a linker. Finally anti-miR-181b is condensed via electrostatic interactions. In vitro and in vivo experiments show that PTPAuNC-NPs can efficiently deliver anti-miR-181b into target sites to suppress tumor growth, and considerably decrease tumor volumes in SMMC-7721 tumor-bearing nude mice under near-infrared radiation. All these results suggest that PTPAuNC-NP gene delivery system with combination of gene therapy and photothermal therapy will be of great potential use in future cancer therapy. [ABSTRACT FROM AUTHOR]

A direct competitive enzyme-linked immunosorbent assay (dc-ELISA) has been developed for the quantitative detection of the dicyclohexyl phthalate (DCHP) in some liquid food. Specific polyclonal antisera to DCHP was raised, using the hapten-bovine serum albumin conjugates as the immunogen. The conjugate of horseradish peroxidase (HRP) with antibody was used as the detectable probe to provide the direct measurement of the antigen and analyte, which was synthesised by a modified glutaraldehyde method. Under the optimised assay, the quantitative working range was from 0.1 to 100 ng mL−1(R2=0.9989), with a limit of detection (LOD) of 0.03 ng mL−1, and a recovery of 96.6–112.4%. The specificity and accuracy of developed method were evaluated. The cross-reactivities of antibody with structurally related phthalate esters were less than 10%. Results obtained indicated that the dc-ELISA was a sensitive, low expense method to improve the routine monitoring of trace constituents in some liquid food. [ABSTRACT FROM AUTHOR]

A highly sensitive and specific direct competitive enzyme-linked immunosorbent assay has been developed for the detection of dipropyl phthalate (DPrP) based on antibody-coating format. The specific polyclonal antibodies against DPrP raised in rabbits. The conjugates of the antigen with horseradish peroxidase (HRP) were used as the detectable probe. Under the optimal conditions, the limit of detection of the method was 0.01 ng/mL, and a good quantitative working range of 0.01–16 ng/mL (R2=0.995) was obtained. The cross-reactivities of four structurally related phthalate esters were below 12% and did not interfere significantly the analysis of DPrP. The accuracy of the immunoassay has been evaluated and validated by analyzing real and spiked leachate from plastic food contact materials. The recoveries of DPrP ranged from 85.9% to 109.4%. This developed dc-ELISA was reliable, accurate and highly sensitive. [ABSTRACT FROM PUBLISHER]

A direct competitive fluorescence immunoassay (dc-FIA) and a direct competitive enzyme-linked immunosorbent assay (dc-ELISA) for the screening of dimethyl phthalate (DMP) in water samples were developed. The immunoassays utilise polyclonal antibodies against DMP raised in rabbits. The anti-DMP antibodies were linked to horseradish peroxidase (HRP) and fluorescein isothiocyanate (FITC). Under the optimal experimental conditions, the dc-ELISA has a linear working range of 0.1–2000 ng/ml (R 2=0.993) with a limit of detection of 0.09 ng/ml. In the dc-FIA, the linear working range was 0.05–30 ng/ml (R 2=0.996), and the limit of detection was 0.02 ng/ml, which is approximately four-fold more sensitive than the dc-ELISA using the same antibody and coating antigen. The results show low cross-reactivity with other structurally related compounds. The proposed methods are successfully applied to determine the DMP contaminants with a simple extraction procedure, and good recoveries were obtained. [ABSTRACT FROM AUTHOR]

Much of the discussion on hydrological trends and variability in the source region of the Yellow River centres on the mean values of the mainstream flows. Changes in hydrological extremes in the mainstream as well as in the tributary flows are largely unexplored. Although decreasing water availability has been noted, the nature of those changes is less explored. This article investigates trends and variability in the hydrological regimes (both mean values and extreme events) and their links with the local climate in the source region of the Yellow River over the last 50 years (1959-2008). This large catchment is relatively undisturbed by anthropogenic influences such as abstraction and impoundments, enabling the characterization of widely natural, climate-driven trends. A total of 27 hydrological variables were used as indicators for the analysis. Streamflow records from six major headwater catchments and climatic data from seven stations were studied. The trend results vary considerably from one river basin to another, and become more accentuated with longer time period. Overall, the source region of the Yellow River is characterized by an overall tendency towards decreasing water availability. Noteworthy are strong decreasing trends in the winter (dry season) monthly flows of January to March and September as well as in annual mean flow, annual 1-, 3-, 7-, 30- and 90-day maxima and minima flows for Maqu and Tangnag catchments over the period 1959-2008. The hydrological variables studied are closely related to precipitation in the wet season (June, July, August and September), indicating that the widespread decrease in wet season precipitation is expected to be associated with significant decrease in streamflow. To conclude, decreasing precipitation, particularly in the wet season, along with increasing temperature can be associated with pronounced decrease in water resources, posing a significant challenge to downstream water uses. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract In recent years, cancer treatment has been facing the challenge of increasing antitumor efficiency and avoiding severe adverse effects simultaneously. In this study, we designed a controlled release drug delivery system, doxorubicin (Dox)-loaded and hyaluronic acid (HA)-modified PEGylated gold nanocages (AuNCs), which was designated as PEG-HAn-AuNCs/Dox (n represented 10n HA repeating units were modified on each AuNC). In this system, AuNCs were applied as the photothermal cores, Dox was employed as the model drug, HA was applied as the tumor-microenvironment responsive switch to achieve controlled release, and poly (ethylene glycol) (PEG) was used as the stealth polymer to prolong systemic circulation time. Firstly, we evaluated the physical and chemical properties of the PEG-HAn-AuNCs/Dox with different ratios of HA to AuNC and found that PEG-HA4-AuNCs/Dox was the optimal. Secondly, PEG-HA4-AuNCs/Dox revealed the feature of controlled release, namely, the drug release was triggered by hyaluronidase (HAase) and accelerated by the acidic pH and near-infrared (NIR) irradiation. And then PEG-HA4-AuNCs/Dox could be effectively delivered to a cultured SMMC-7721 cell line in vitro and the tumor tissues of the subcutaneous mouse models of hepatocellular carcinoma (HCC) in vivo. Finally, the results demonstrated the synergetic therapy, namely the combination of chemotherapy and photothermal therapy (PTT) (defined as chemo-photothermal therapy) mediated by PEG-HA4-AuNCs/Dox, could efficiently inhibit the tumor growth both in vitro and in vivo. Therefore, the advantages of PEG-HA4-AuNCs/Dox endowed it as a great potential candidate for HCC treatment. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

The development of effective oral preparations of 2-methoxyestradiol (2-ME) has been a worldwide problem. In this study, breakthrough progress has been made in oral delivery of 2-ME by encapsulating 2-ME micelles in pH-responsive microspheres. 2-ME micelles with small particle size (58 nm) and high drug loading (7.94 ± 0.23%) were successfully prepared and showed slower release characteristics and 12.8 times higher cytotoxicity on 4T1 cells than free 2-ME. The pH-sensitive microspheres could slowly release 82% of 2-ME micelles for 10 h in PBS (7.4). After oral administration to rats, 2-ME-micelles-microspheres compared to 2-ME micelles could prolong significantly blood retention time (MRT) of 2-ME by 12 times and enhance oral absolute bioavailability from 49.99% to 121.68%. In vivo imaging of 4T1 tumor-bearing mice showed that retention time and intensity of the fluorescence signal in each 2-ME preparation group all were consistent with the pharmacokinetic results and intact 2-ME micelles in the microspheres could be absorbed in intestine to blood to target to tumor. Furthermore, after the 4T1 tumor-bearing mice were treated with oral 2-ME-micelles-microspheres for 21 days, the tumor growth inhibition rate achieved 94.93% and the mice weight gained significantly, indicating their high antitumor activity and low toxicity. While oral administration of 2-ME micelles and 2-ME microspheres all were ineffective under the same conditions. Therefore, micelles-microspheres might be a promising candidate for oral administration of 2-ME for cancer therapy. [ABSTRACT FROM AUTHOR]

Multidrug resistance (MDR) remains a formidable challenge to effective clinical cancer therapy. Herein, a nonviral gene delivery system HA/anti-miR-21/PPAuNCs to overcome MDR was reported. This system could condense the microRNA-21 inhibitor (anti-miR-21) into hyaluronic acid-conjugated and polyethylenimine-modified PEGylated gold nanocages (AuNCs) and had good stability. In vitro studies demonstrated that HA/anti-miR-21/PPAuNCs could enhance intracellular DOX accumulation in DOX-resistant HCC cells (HepG2/ADR cells) and increase the sensitivity to DOX of HepG2/ADR cells through upregulating PTEN protein expression mediated by anti-miR-21 and downregulating P-gp protein expression mediated by the hyperthermia of HA/PPAuNCs upon mild near-infrared irradiation. Furthermore, the therapeutic effects had been enhanced due to the combination of chemotherapy, gene therapy, and photothermal therapy. Besides, HA/anti-miR-21/PPAuNCs have a good biocompatibility. These findings can provide new insights and strategies for the treatment of cancers with MDR.

Glucose-responsive insulin delivery systems, which can maintain a stable level of blood glucose, have been proposed as a promising method to treat diabetes. Such systems can reduce potential toxicity and enhance patient compliance compared to traditional therapies. Accordingly, we designed a mesoporous silica nanoparticle (MSN)-based glucose-sensitive and self-regulated drug release system to achieve the goal of long circulation and "touch switch" in vivo. In this system, carboxyphenylboronic acid (CPBA) was first modified on the surface of MSN using amidation reaction. Insulin (INS) was then loaded in the channels of MSN (CPBA-MSN/INS) through physical adsorption, and sodium alginate (SA) was introduced onto the surface of the CPBA-MSN/INS nanoparticles as the gatekeeper via amidation reaction (SA/CPBA-MSN/INS). We found the drug loading capacity of INS was 261 mg/g. In the normal range of blood glucose, INS was scarcely released due to the reversible covalent interaction between 1,2-diols of SA and CPBA. Within the high concentration of glucose, the boronate esters could be dissociated, which results in the mesoporous channels opening and the release of INS. In vivo experiments on diabetic mice showed SA/CPBA-MSN/INS sustained a normal blood glucose level for up to 12 h with a single dose. Moreover, the lipid metabolism disorder and organ damage of diabetic mice were alleviated after treatment with SA/CPBA-MSN/INS. Therefore, SA/CPBA-MSN/INS characterized by an "on-off" regulated drug release property and high biosafety shows promise for applications in diabetes treatment.