Search

The present study investigates the diffusion bonding of leaded-tin bronze (CuSn10Pb10) and 45 steel via surface modification method, i.e., hot-dip tin coating (HDTC) treatment, so as to provide guidance for the application of copper/steel joints. The effect of HDTC treatment on the interfacial microstructure and mechanical performance of CuSn10Pb10/45 steel joint is established. The results show that the interfacial crack is formed during diffusion bonding of CuSn10Pb10 and 45 steel without HDTC treatment. However, HDTC treatment evidently promotes the mutual diffusion of elements between CuSn10Pb10 and 45 steel, and a metallurgical CuSn10Pb10/HDTC 45 steel joint with a transition layer consisting of Fe-enriched solid solution, Cu-enriched solid solution and Cu10Sn3 intermetallic compound is obtained. The CuSn10Pb10/HDTC 45 steel joint at a bonding temperature of 900 °C shows higher shear strength and better ductility than that of CuSn10Pb10/45 steel joint. With the increasing of bonding temperature, the promoted occurrence and aggregation of Cu10Sn3 intermetallic compound in the CuSn10Pb10/HDTC 45 steel bonding interface results in the increase in shear strength, but the decrease in ductility of joint.

For A-site substituted AA'BO3 perovskite, the doped A' element is easy to migrate to the surface and form segregation of A'Ox, which could partially block active B sites and thus reduce catalytic activity. In the present work a La0.8Sr0.2CoO3-δ perovskite-type solid was first prepared and then treated with acetic acid to eliminate SrO segregation on its surface. The obtained catalyst (LCSO-a) possessed a significantly enhanced catalytic activity for toluene oxidation in the 220–260 °C range. This promotion effect might be attributed to the increase in the concentration of active surface oxygen species and the reduction in their binding strength. In addition, the LCSO-a catalyst showed very good stability and water resistance.

Objective: Ephedrine hydrochloride (EH) is a major component from Ephedra sinica STAPF, which is used as a traditional Chinese herbal medicine. This study was designed to investigate the effect of EH on water metabolism and further explore the relevant signaling pathway of body fluid regulation in “lung governing regulation of water passage” using a rabbit model of mechanical ventilation. The molecular mechanism of the EH effect in the kidney was also investigated. Methods: Rabbits were randomly divided into a control group, model group, EH group, and dexmedetomidine hydrochloride (DH) group. Urine volume was measured by the intubation method and pathologic changes in lung and renal tissue were measured by hematoxylin and eosin staining. Nitric oxide (NO) production in lung, serum, and kidney were analyzed using chemical methods. An ELISA was used to analyze angiotensin II (Ang II), antidiuretic hormone (ADH), prostaglandin E2 (PGE2), atrial natriuretic peptide (ANP), and endothelin-1 (ET-1) levels in the lung, serum, and kidney. Aquaporin-1 (AQP1) and aquaporin-2 (AQP2) mRNA and protein expression in the kidney was determined using qRT-PCR and immunohistochemistry. Results: EH significantly inhibited the decrease in the total urine volume in the third and fourth stages, and displayed significant regulatory effects on NO, Ang II, ADH, PGE2, ANP, and ET-1 in serum, lung, and renal tissues compared with the model group. In the kidney, AQP1 and AQP2 mRNA and protein expression in the EH group were remarkably down-regulated compared with the model group. Conclusion: EH exerted a regulatory effect on water metabolism by diffusing the lung and increased urine volume in the rabbit model, which was consistent with the decrease in kidney AQP1 and AQP2 expression levels that led to an increase in urine volume. EH could assist with DH to exert a protective effect on the clinical application of mechanical ventilation. Keywords: Mechanical ventilation, Ephedrine hydrochloride, Dexmedetomidine hydrochloride, Humoral regulation

Objective: To explore biological mechanisms underlying the traditional Chinese medicine theory of “lung governing the regulation of water passage” by observing effects of mechanical ventilation on urine volume and related bioactive substances. Methods: A total of 16 male rabbits were randomly divided into control and lung expansion model groups (n = 8 per group), which were examined during the following four respiratory intervention stages (10 minutes each): (1) free breathing without any respiratory intervention; (2) lung expansion induced by mechanical ventilator; (3) free breathing without ventilator intervention; (4) cutting of bilateral sympathetic, vagus, and depressor nerves with mechanical ventilation. Data for breathing rate, blood pressure, and urine drops were recorded with a Medlab data acquisition system. Levels of nitric oxide (NO), antidiuretic hormone (ADH), endothelin 1 (ET-1), angiotensin II (AngII), prostaglandin E2 (PGE2), and atrial natriuretic peptide (ANP) were detected in lung tissue, kidney tissue, and serum by enzyme-linked immunosorbent assay. Protein expression of aquaporins 1 and 2 (AQP1 and AQP2) was detected in kidney tissue by immunohistochemistry, while Aqp1 mRNA and Aqp2 mRNA levels in kidney tissue were detected by real-time quantitative polymerase chain reaction. Histopathological changes in lung and kidney tissues were examined by hematoxylin and eosin staining. Results: Compared with the control group, number of urine drops during the second and fourth stages is significantly decreased in the model group (P

Injectable hydrogels, which are polymeric materials that are characterized by their ability to be injected in a liquid form into cavities and subsequently undergo in situ solidification, have garnered significant attention. These materials are extensively used in a range of biomedical applications. This study synthesized several injectable composite hydrogels through the mild Schiff base reaction while imposing different concentrations of quaternary ammonium chitosan and oxidized pullulan. Subsequent characterizations revealed a consistent and coherent porous structure within the hydrogels with smooth inner walls. The hydrogels were also determined to possess good adhesion, mechanical properties, self-healing ability, and injectability. Furthermore, antimicrobial tests against Escherichia coli and Staphylococcus aureus demonstrated antibacterial properties, which improved with increasing concentrations of quaternary ammonium chitosan. Co-culturing with skin fibroblasts demonstrated that the injectable hydrogels exhibited favourable biocompatibility and the capacity to boost cellular activity, thus underscoring its potential for use in biomedical applications.

Autoimmune encephalitis (AE) is an inflammatory disease of the central nervous system characterized by the production of various autoimmune antibodies targeting neuronal proteins. The pathogenesis of AE remains elusive. Accumulating evidence suggests that lymphocytes, particularly B and T lymphocytes, play an integral role in the development of AE. In the last two decades, autoimmune neural antibodies have taken center stage in diagnosing AE. Recently, increasing evidence has highlighted the importance of T lymphocytes in the onset of AE. CD4+ T cells are thought to influence disease progression by secreting associated cytokines, whereas CD8+ T cells exert a cytotoxic role, causing irreversible damage to neurons mainly in patients with paraneoplastic AE. Conventionally, the first-line treatments for AE include intravenous steroids, intravenous immunoglobulin, and plasma exchange to remove pathogenic autoantibodies. However, a minority of patients are insensitive to conventional first-line treatment protocols and suffer from disease relapse, a condition referred to as refractory AE. In recent years, new treatments, such as rituximab or CAAR-T, which target pathogenic lymphocytes in patients with AE, have offered new therapeutic options for refractory AE. This review aims to describe the current knowledge about the function of B and T lymphocytes in the pathophysiology of AE and to summarize and update the immunotherapy options for treating this disease.

This study focuses on the development of printable biomaterial inks using a bacterial exopolysaccharide (EPS) called polyglucuronic acid (PGU), along with bacterial cellulose (BC) or methylcellulose (MC). The physical, mechanical, and biological properties of the hydrogels originating from these inks were assessed through scanning electron microscope (SEM) imaging, rheological tests, and cytocompatibility assessments. The results demonstrate that incorporating PGU into BC or MC inks enhances the shape fidelity, printability, and rigidity of the resulting 3D-printed hydrogels. Moreover, all crosslinked hydrogels based on PGU and BC or MC exhibited cytocompatibility with fibroblast cells (3T3-L1). These findings highlight the potential of the PGU/BC or MC-based biomaterial inks for various tissue engineering applications, including injectable gels, drug delivery systems, and soft tissue models. Furthermore, the study underscores the potential of using bacterial PGU as an alternative to alginate in biomaterial ink development and 3D printing.

The Multidimensional Forced Choice (MFC) test is frequently utilized in non-cognitive evaluations because of its effectiveness in reducing response bias commonly associated with the conventional Likert scale. Nonetheless, it is critical to recognize that the MFC test generates ipsative data, a type of measurement that has been criticized due to its limited applicability for comparing individuals. Multidimensional item response theory (MIRT) models have recently sparked renewed interest among academics and professionals. This is largely due to the development of several models that make it easier to collect normative data from forced-choice tests. The paper introduces a modeling framework made up of three key components: response format, measurement model, and decision theory. Under this paradigm, four IRT models were chosen as examples. Following that, a comprehensive study is carried out to compare and characterize the parameter estimation techniques used in MFC-IRT models. This work then examines empirical research on the concept by analyzing three distinct domains: parameter invariance testing, computerized adaptive testing (CAT), and validity investigation. Finally, it is recommended that future research initiatives follow four distinct paths: modeling, parameter invariance testing, forced-choice CAT, and validity studies.

Introduction: Exopolysaccharides (EPSs) are high-value functional biomaterials mainly produced by bacteria and fungi, with nutraceutical, therapeutic and industrial potentials. Objectives: This study sought to characterize and assess the biological properties of the EPS produced by the yeast Papiliotrema terrestris PT22AV. Methods: After extracting the yeast's DNA and its molecular identification, the EPS from P. terrestris PT22AV strain was extracted and its physicochemical properties (structural, morphological, monosaccharide composition and molecular weight) were characterized. The EPS's in vitro biological activities and in vivo wound healing potential were also evaluated. Results: The obtained EPS was water-soluble and revealed an average molecular weight (Mw) of 202 kDa. Mannose and glucose with 97% and 3% molar percentages, respectively, constituted the EPS. In vitro antibacterial activity analysis of the extracted EPS exhibited antibacterial activity (>80%) against Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis at a concentration of 2 mg/mL. The EPS showed cytocompatibility against the human fibroblast and macrophage cell lines and the animal studies showed a dose-dependent wound healing capacity of the EPS with higher wound closure at 10 mg/mL compared to negative and positive control after 14 days. Conclusion: The EPS from P. terrestris PT22AV could serve as a promising source of biocompatible macromolecules with potential for skin wound healing.

In this paper, we propose BiTNet, a real-time object detection network, for enhancing teaching quality and providing feedback through real-time analysis of student behavior in classroom. BiTNet addresses challenges faced by current methods, such as occlusion and small objects in images. Specifically, it incorporates an Efficient Transformer Block (ETB) and Efficient Convolution Aggregation Block (ECAB) for extracting image features. ETB uses convolutional multi-head self-attention (CMHSA) to capture contextual information thus improves the capability to recoginze occluded objects. Its homogeneous multi-branch design reduces the computational costs. The single aggregation operation of ECAB aggregates the extracted features into a single feature map, improving the accuracy of recognition while reducing the computational cost. Then, the semantic and positional information extracted from the backbone are fused in Bi-directional Feature Pyramid Network (BiFPN). BiTNet also employs a smaller size detection head for recognition of small objects. Experimental results on classroom behavior dataset demonstrate that our proposed method has impressive accuracy (82.9%) and speed (256.7 FPS on GPU, 30.7 FPS on CPU, and 18.9 on camera). We further experiment with our method on Pascal VOC 2007 and VisDrone2021, validating BiTNet’s generalization and its capability to recognize small objects. In conclusion, BiTNet has a simple yet efficient network structure and feature extraction module, which reduce computational cost while maintaining recognition accuracy, making it a contender for real-time classroom behavior recognition tasks.

Repair of osteochondral defects and regeneration of cartilage is a major challenge. In this work, the mesenchymal stem cells (MSCs)-laden hydrogel was designed using silk fibroin (SF) and gelatin methacrylate (GelMA), to encapsulate platelet-rich plasma (PRP). Initially, GelMA was synthesized, and SF was prepared using silkworm cocoon, then MSCs-laden SF/GelMA (SG) hydrogel was fabricated. The physicochemical properties of the hydrogels were evaluated using Fourier-transform infrared spectroscopy, scanning electron microscope, and rheometry. After hydrogel preparation, the viability of MSCs in the hydrogels was investigated via CCK-8 analysis and fluorescent images. The MSCs-laden SG hydrogel containing PRP was subsequently injected into the cartilage defect area in Sprague Dawley rats. Hematoxylin and eosin (H&E), Masson staining, and Mankin scores evaluation confirmed the new cartilage formation in 8 weeks. The results presented in the study, therefore, showed that the prepared MSCs-laden SG hydrogel loaded with PRP has the potential for cartilage reconstruction, which is crucial to the treatment of knee osteoarthritis.

Synchronous fluorescence spectroscopy (SFS) combined with Gaussian band fitting, two-dimensional correlation (2D-COS) and perturbation-correlation moving-window two-dimensional (PCMW2D) can provide an excellent mothed to extract fluorescent components of dissolved organic matter (DOM) and reveal its variations in an urban river. Fifteen water samples were collected from the Anyanghe River, which flew across the town, urban, and rural regions. Five peaks (peak1 tyrosine-like, peak2 tyrosine-like, peak3 tryptophan-like, peak4 microbial humic-like, peak5 fulvic-like) were extracted using the Gaussian Amp model from the SFS in the river, while the peak1 only occurred in the rural region. The microbial humic-like in the town region accounting for 50.02 % was the representative substance. The tyrosine-like dominated in the rural regions, for its percentage range was 62.26 %-75.78 %. The average percnetage of tyrosine-like (29.77 %) in the urban region was similar to that of the tryptophan-like (21.86 %), microbial humic-like (25.56 %), and fulvic-like (22.82 %). Based on the two-dimensional correlation, the variation order of DOM fractions in the town and urban regions was tryptophan → tyrosine → microbial humic → fulvic, and the variation order in the rural region was tyrosine → tryptophan → microbial humic → fulvic. This indicated that the changing trend of DOM fractions existed from the labile protein-like to the stable humus in the whole river. According to the perturbation-correlation moving-window two-dimensional correlation spectroscopy, the spectral intensity of tyrosine-like should be linear increase in the town and urban regions, and concave increase in the rural region. The spectral intensity trend of tryptophan-like mainly was linear increase in the whole river. And the intensity of microbial humic-like showed the rough convex increase in the whole river. The trend of the fulvic-like in the town and rural regions was similar to the microbial humic-like. However the fulvic-like intensity in the urban region exhibited a trend from the concave increase to the convex increase, which was obviously different from the tyrosine-like, tryptophan-like and microbial humic-like. This attribute that the untreated domestic sewage in the urban region could discharge into the river. Therefore, for small amounts of samples, the SFS combined with Gaussian band fitting, 2D-COS and PCMW2D can be used as a powerful tool to investigate fluorescent components of DOM, and reveal their variations along the river.

Obesity is a foremost health issue that affects about 1.6 million people out of which 400 million worldwide. Epidemiological evidences prove obesity is the primary cause for various metabolic ailments e.g. diabetes. Poria cocos possess extensive biological actions, for instance, antioxidant, anti-inflammatory, antitumor, immunomodulatory actions. The primary limitation of all phytomedicine was their poor bioavailability hence in this investigation, we bio-fabricated the gold nanoparticles from Poria cocos aqueous extract and inspected their potency to treat obesity. Obese rat model were produced via fed the young female rats with high fat food for 8 weeks regimen. Further to confirm the potency of Poria cocos gold nanoparticles against obesity induced metabolic disorders we treated obese rats with low dose streptozotocin in the conclusion of the investigational time. The synthesis of Poria cocos gold-nanoparticles was evidenced via the UV-Spectroscopic study and characterized with SEM, TEM and EDAX studies. The anti-obesity actions of Poria cocos gold-nanoparticles were investigated by estimating the glucose profile, kidney markers, lipid profile, inflammatory cytokines, adipocyte markers, antioxidants in the Poria cocos gold nanoparticles treated obese rats. To confirm the Poria cocos gold nanoparticles role on inhibiting the obesity induced metabolic disorders we analyzed the histopathological changes in cardiac tissues. Our physical characterization confirms the synthesized Poria cocos gold nanoparticles assure the distinctions of influential nanoparticles to be utilized for the treatment. The results from biochemical and histopathological analysis confirms Poria cocos gold nanoparticles is a persuasive antidiabetic, anti-inflammatory, antioxidant, anti-obesity drug. Overall our results authentically confirm Poria cocos gold nanoparticles is a potent anti-obesity drug and it also protects from obesity induced metabolic disorders.

Introduction and objectives: Long non-coding RNA (lncRNA) EPIC1 (epigenetically-induced lncRNA1) is likely involved in human cancer by promoting cell cycle progression. Our study was carried out to investigate the involvement of EPIC1 in gallbladder cancer (GBC). Methods: Expression levels of EPIC1 in two types of tissues (GBC and paracancerous) and plasma were measured by performing qPCR. GBC-SD and SGC-996 cells were transfected with low expression in tumor (LET) and EPIC1 expression vectors. Results: The present study found that EPIC1 was upregulated in tumor tissues than in paracancerous tissues of GBC patients, and plasma levels of EPIC1 were significantly correlated with levels of EPIC1 in tumor tissues. LncRNA LET was downregulated in tumor tissues than in paracancerous tissues and was inversely correlated with EPIC1 in both tumor tissues and paracancerous tissues. Overexpression of EPIC1 led to downregulated LET, and LET overexpression also mediated the downregulation of EPIC1. EPIC1 led to accelerated GBC cell proliferation and inhibited apoptosis. Overexpression of LET played opposites roles. In addition, LET overexpression attenuated the effects of EPIC1 overexpression on cancer cell proliferation and apoptosis. Conclusions: LncRNA EPIC1 promoted proliferation and inhibited apoptosis of GBC cells by interacting with LET.

In this study, green tea waste (GTW) was used to synthesize the iron oxide (IO) nanoparticles (IO@GTW) to facilitate the adsorption of heavy metals from wastewaters. To satisfy structural integrity needs, the synthesized IO@GTW was incorporated into a polyvinyl alcohol (PVA)/alginate polymer network to obtain PVA/alginate/IO (PAI) hydrogels. Experimental techniques of transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) were subsequently used to confirm the successful synthesis of IO nanoparticles. Scanning electron microscopy (SEM) established the porous microstructure of PAI hydrogels, while FT-IR analysis revealed the physical incorporation of IO@GTW in PAI hydrogels. The adsorption of Cu2+ and Cr6+ on PAI hydrogels was subsequently investigated. The present study was able to show that the removal ratio and adsorption capacity of the synthesized PAI hydrogels depended on the pH, initial concentration of metal ions in the solution, and contact time. The equilibrium isotherms of Cu2+ and Cr6+ adsorption were well-described using Langmuir and Freundlich isotherm models. The adsorption kinetics of Cu2+ can be modelled using the pseudo-second-order model, and the adsorption kinetics of Cr6+ can be modelled using both pseudo-first-order and intraparticle diffusion models. This study, therefore, demonstrates the functionality of integrating green tea waste in a polymeric composite to perform as an effective and green adsorbent for heavy metal removal, thus indicating the viability of its future application in wastewater treatment operations.

This study aims to investigate the oxidative degradation of chitosan to produce chitooligosaccharides (CHOS) as a potential bioagent for biomaterials engineering. CHOS was produced via microwaved-assisted oxidative degradation of chitosan by using hydrogen peroxide in an acidic aqueous solution. The effects of the H2O2 concentration, reaction time, microwave power, and reaction temperature on the degradation of chitosan were investigated. Following optimization of these parameters, three soluble CHOS fractions CHOS 1 (4-8 kDa), CHOS 2 (3-5 kDa), and CHOS 3 (1-3 kDa) were synthesized and the physicochemical, structural, thermal properties and water solubility were investigated. No significant structure alteration of the initial chitosan was detected by Fourier transform infrared spectroscopy (FTIR), UV–vis, and nuclear magnetic resonance (NMR) analyses, making our microwave-assisted oxidative degradation a valuable method for the production of CHOS. Interestingly, CHOS fractions exhibited improved radical scavenging activities and antibacterial activities compared to the initial chitosan. The half maximal effective concentration (EC50) of the CHOS fractions were found to be in the range of 2.69–0.724 mg/mL significantly lower than the chitosan (7.75, mg/mL). Besides, the CHOS fractions exhibited lower minimum inhibitory concentration (MIC; in the range of 62.5–500 µg/mL) compared to the initial chitosan (>1000 µg/mL). Moreover, the 3T3-Ll fibroblast cells treated with CHOS fractions exhibited more than 95% viability after 48 h of culture. Cell migration and collagen production assays also showed the positive effect of CHOS fractions, particularly CHOS 3. These results indicate that CHOS can be a promising bioactive agent in biomedical applications, in particular for wound healing applications.

Purpose: To investigate the changes and underlying mechanisms in parents' safety awareness and the use of child safety seats after the mandatory legislation in Shanghai city, China. Methods: This study was carried out by Shanghai Key Laboratory of Environment and Children's Health using a multi-stage, simple random sampling method. Volunteers with children aged 0–12 months were recruited. Child safety seats were sent to each volunteer's family. Telephone encounters and/or on-site visits were used to collect data from parents using a phased survey on children's safety during car use. Results: Among all respondents, 91.2% had heard of motor vehicle accidents involving children, and 97.2% could describe the appropriate use of a safety seat to minimize the risk of child injury in a collision. Among 1078 families with newborns, awareness of child safety seats was 91.9%. There were 86% patients aware that new laws and regulations have been released regarding the use of child safety seats, and 98.5% of them plan to comply with the new laws. Moreover, 61% patients think that taxis should be routinely equipped with child safety seats. Conclusion: The parents in Shanghai obtained a high level of awareness of children's traffic safety after the introduction of child safety seats legislation, and had a positive experience related to the use of child safety seats. Taxi may be an important area of focus for implementation of child traffic safety. Traffic safety laws and regulations with further impact should be continuously studied. Keywords: Child, Child restraint systems, Traffic injuries, Awareness, Shanghai

Cranial placodes are embryonic structures essential for sensory and endocrine organ development. Human placode development has remained largely inaccessible despite the serious medical conditions caused by the dysfunction of placode-derived tissues. Here, we demonstrate the efficient derivation of cranial placodes from human pluripotent stem cells. Timed removal of the BMP inhibitor Noggin, a component of the dual-SMAD inhibition strategy of neural induction, triggers placode induction at the expense of CNS fates. Concomitant inhibition of fibroblast growth factor signaling disrupts placode derivation and induces surface ectoderm. Further fate specification at the preplacode stage enables the selective generation of placode-derived trigeminal ganglia capable of in vivo engraftment, mature lens fibers, and anterior pituitary hormone-producing cells that upon transplantation produce human growth hormone and adrenocorticotropic hormone in vivo. Our results establish a powerful experimental platform to study human cranial placode development and set the stage for the development of human cell-based therapies in sensory and endocrine disease.

A simple, sensitive and accurate method based on high performance liquid chromatography (HPLC) with diode array detector (DAD) was developed and validated for systematic quality evaluation of one type of traditional Chinese medicine preparations named Xinkeshu (XKS) tablet. In this study, the chromatographic fingerprints of XKS tablet were developed first, 23 peaks were selected as the common peaks to evaluate the similarities among different batches of XKS samples, which were manufactured in a long time span of three years. Additionally, simultaneous quantification of six markers in XKS tablet, including Danshensu, Protocatechuic aldehyde, Puerarin, Daidzin, Salvianolic acid B and Daidzein, was performed. The validation results showed that the developed method was specific, accurate, precise and robust. The preliminary explanation on why a close similarity between fingerprints did not exactly mean similar contents of chemical components in samples was given. The contribution of each chromatographic peak to similarity was also evaluated. The developed method offers an efficient, reliable and practical approach for systematic quality evaluation of XKS tablet. Keywords: Fingerprint analysis, Quality evaluation, Multi-ingredient quantitative analysis, Xinkeshu tablet, High-performance liquid chromatography