The fulfillment of corporate social responsibility (CSR) is an engineering system, and all the parts of the system form a new social responsibility model. This paper systematically constructs a new ...social responsibility model under the major emergencies. The new model contains the inner layer and the outer layer. The inner layer is the driving force of the model, and the outer layer is the implementation part of the model. The inner layer drives the outer layer, and the outer layer takes a series of concrete measures under the action of the inner layer. At the end of the social responsibility cycle, a new social responsibility cycle will be started because of the change of the inner layer. “emergency in left-hand” and “responsibility in right-hand ” is an eternal topic.
Polymer composites that have high thermal conductivity have become one of the most promising solutions needed to satisfy the thermal management requirements for high-power electrical and electronic ...equipment. In this work, a strategy relying on aligning carbon fibers through the application of a stress field is proposed. Ultrahigh through-plane thermal conductive epoxy composites with carbon fiber networks have been prepared by in-situ solidification within an epoxy. The thermal conductivity of these epoxy composites reaches as high as 32.6 W m−1 K−1 at 46 wt percent (wt%) of carbon fibers, which is about 171 times that of the pure epoxy. The alignment condition for the carbon fibers for a carbon fiber composite in which stress has been applied and a blended carbon fiber composite are compared using micro compute tomography (micro-CT) and scanning electron microscopy (SEM). These epoxy composites display attractive thermal properties and provide a practical route to satisfy the thermal dissipation requirements raised by the development of modern electrical devices and systems.
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•Aligning carbon fiber to preparing high through-plane thermal conductive composite.•Using mechanical method to construct thermal conductive path.•Thermal conductivity rises with well-alignment of filler becomes.•This method is simple and its cost is low.
In this study, the Zn nanoparticles were synthesized using the peel extract of Citrus aurantium. The nanoparticles were characterized by different chemical techniques including UV‐Vis. and FT‐IR ...spectroscopy, and SEM technique. The results revealed a spherical shape with an average size of 41.17 nm was identified for the green‐synthesized nanoparticles. In the antioxidant test, the IC50 of nanoparticles and butylated hydroxytoluene (BHT) against DPPH free radicals were 115 and 96 μg/mL, respectively. In the cellular and molecular part of the recent study, the treated cells with nanoparticles were assessed by the MTT assay for 48 h about the cytotoxicity and anti‐human bone cancer properties on normal (HUVEC) and cancer cell lines, that is, A‐673 and HS‐729. The IC50 of nanoparticles were 278 and 256 μg/mL against A‐673 and HS‐729 cell lines, respectively. The viability of malignant cell lines reduced dose‐dependently in the presence of Zn nanoparticles. It seems that the anti‐cancer effect of recent nanoparticles is due to their anti‐oxidant effects. After evaluating the effectiveness of this formulation in clinical trial researches, it can be a good alternative to chemotherapy drugs.
In this study, the Zn nanoparticles were synthesized using the peel extract of Citrus aurantium. The nanoparticles were characterized by different chemical techniques including UV‐Vis. and FT‐IR spectroscopy, and SEM technique. The results revealed a spherical shape in the average size of 41.17 nm was identified for the green‐synthesized nanoparticles. In the anti‐oxidant test, the IC50 of nanoparticles and BHT against DPPH free radicals were 115 and 96 μg/mL, respectively. In the cellular and molecular part of the recent study, the treated cells with nanoparticles were assessed by the MTT assay for 48 h about the cytotoxicity and anti‐human gastric cancer properties on normal (HUVEC) and gastric cancer cell lines, that is, NCI‐N87 and MKN45. The IC50 of nanoparticles were 278 and 256 μg/mL against NCI‐N87 and MKN45 cell lines, respectively. The viability of malignant gastric cell line reduced dose‐dependently in the presence of Zn nanoparticles. It seems that the anti‐human gastric cancer effect of recent nanoparticles is due to their anti‐oxidant effects. After evaluating the effectiveness of this formulation in clinical trial research, it can be a good alternative to chemotherapy drugs.
Cancer incidence and mortality are rapidly increasing worldwide; therefore, effective therapies are required in the current scenario of increasing cancer cases. Polysaccharides are a family of ...natural polymers that hold unique physicochemical and biological properties, and they have become the focus of current antitumour drug research owing to their significant antitumour effects. In addition to the direct antitumour activity of some natural polysaccharides, their structures offer versatility in synthesizing multifunctional nanocomposites, which could be chemically modified to achieve high stability and bioavailability for delivering therapeutics into tumor tissues. This review aims to highlight recent advances in natural polysaccharides and polysaccharide-based nanomedicines for cancer therapy.
Wide applications of surface plasmon resonance rely on the in-depth understanding of the near-field distribution over a metallic nanostructure. However, precisely locating the strongest electric ...field in a metallic nanostructure still remains a great challenge in experiments because the field strength decays exponentially from the surface. Here, we demonstrate that the hot spot position for gold nanoparticles over a metal film can be precisely located using surface-enhanced Raman spectroscopy (SERS) by rationally choosing the probe molecules and excitation wavelengths. The finite difference time domain simulation verifies the experimental results and further reveals that the enhancement for the above system is sensitive to the distance between nanoparticles and the metal film but insensitive to the distance of nanoparticles. On the basis of this finding, we propose and demonstrate an approach of using a nanoparticles-on-metal film substrate as a uniform SERS substrate. This work provides a convenient way to probe the location of strong near-field enhancement with SERS and will have important implications in both surface analysis and surface plasmonics.
Impervious surfaces are key indicators for urbanization monitoring and watershed degradation assessment over space and time. However, most empirical studies only extracted impervious surface from ...spatial, temporal or spectral perspectives, paying less attention to integrating multiple dimensions in acquiring continuous changes in impervious surfaces. In this study, we proposed a neighborhood-based spatio-temporal filter (NSTF) to obtain the continuous change information of impervious surfaces from multi-temporal Landsat images in the Qinhuai River Basin (QRB), Jiangsu, China from 1988–2017, based on the results from semi-automatic decision tree classification. Moreover, we used the expansion intensity index (EII) and the landscape extension index (LEI) to further characterize the spatio-temporal characteristics of impervious surfaces on different spatial scales. The preliminary results showed that the overall accuracies of the final classification were about 95%, with the kappa coefficients ranging between 0.9 and 0.96. The QRB underwent rapid urbanization with the percentage of the impervious surfaces increasing from 2.72% in 1988 to 25.6% in 2017. Since 2006, the center of urbanization expansion was shaped from the urban built-up areas of Nanjing and Jiangning to non-urban built-up areas of the Jiangning, Lishui, and Jurong districts. The edge expansion occupied 73% on average among the different landscape expansion types, greatly beyond outlying (12%) and infilling (15%). The window size in the NSTF has a direct impact on the subsequent analysis. Our research could provide decision-making references for future urban planning and development in the similar basins.
With the increasing integration and miniaturization of electronic devices, heat dissipation has become a major challenge. The traditional printed polymer circuit board can no longer meet the heat ...dissipation demands of microelectronic equipment. If the heat cannot be removed quickly and effectively, the efficiency of the devices will be decreased and their lifetime will be shortened. In addition, the development of the aerospace, automobiles, light emitting diode (LED{ TA \1 "LED; lightemitting diode" \s "LED" \c 1 }) and energy harvesting and conversion has gradually increased the demand for low-density and high thermal conductive materials. In recent years, carbon fiber (CF{ TA \1 "CF; carbon fiber" \c 1 }) has been widely used for the preparation of polymer composites due to its good mechanical property and ultra-high thermal conductivity. CF materials easily form thermal conduction paths through polymer composites to improve the thermal conductivity. This paper describes the research progress, thermal conductivity mechanisms, preparation methods, factors influencing thermal conductivity and provides relevant suggestions for the development of CF composites for thermal management.
Exploring the effects of seasonal variation on the gut microbiota of cold-water fish plays an important role in understanding the relationship between seasonal variation and cold-water fish. Gut ...samples of cold-water fish and environmental samples were collected during summer and winter from the lower reaches of the Yalong River. The results of the 16S rRNA sequencing showed that significant differences were identified in the composition and diversity of gut bacteria of cold-water fish. Co-occurrence network complexity of the gut bacteria of cold-water fish was higher in summer compared to winter (Sum: nodes: 256; edges: 20,450; Win: nodes: 580; edges: 16,725). Furthermore, from summer to winter, the contribution of sediment bacteria (Sum: 5.3%; Win: 23.7%) decreased in the gut bacteria of cold-water fish, while the contribution of water bacteria (Sum: 0%; Win: 27.7%) increased. The normalized stochastic ratio (NST) and infer community assembly mechanisms by phylogenetic bin-based null model analysis (iCAMP) showed that deterministic processes played a more important role than stochastic processes in the microbial assembly mechanism of gut bacteria of cold-water fish. From summer to winter, the contribution of deterministic processes to gut bacteria community assembly mechanisms decreased, while the contribution of stochastic processes increased. Overall, these results demonstrated that seasonal variation influenced the gut bacteria of cold-water fish and served as a potential reference for future research to understand the adaptation of fish to varying environments.
FDA-approved anti-PD-L1 antibody drug Atezolizumab is a human IgG1 without glycosylation by an N297A mutation. Aglycosylation of IgG1 has been used to completely remove the unwanted Fc-mediated ...functions such as antibody-dependent cytotoxicity (ADCC). However, aglycosylated Atezolizumab is very unstable and easy to form aggregation, which causes quick development of anti-drug antibody (ADA) in 41% of Atezolizumab-treated cancer patients, eventually leading to loss of efficacy. Here, we report the development of the anti-PD-L1 antibody drug Maxatezo, a glycosylated version of Atezolizumab, with no ADCC activity, better thermo-stability, and significantly improved anti-tumor activity in vivo. Using Atezolizumab as the starting template, we back-mutated A297N to re-install the glycosylation, and inserted a short, flexible amino acid sequence (GGGS) between G237 and G238 in the hinge region of the IgG1 heavy chain. Our data shows that insertion of GGGS, does not alter the anti-PD-L1's affinity and inhibitory activity, while completely abolishing ADCC activity. Maxatezo has a similar glycosylation profile and expression level (up to 5.4 g/L) as any normal human IgG1. Most importantly, Maxatezo's thermal stability is much better than Atezolizumab, as evidenced by dramatic increases of Tm1 from 63.55 °C to 71.01 °C and T
from 60.7 °C to 71.2 °C. Furthermore, the levels of ADA in mice treated with Maxatezo were significantly lower compared with animals treated with Atezolizumab. Most importantly, at the same dose (10 mg/kg), the tumor growth inhibition rate of Maxatezo was 98%, compared to 68% for Atezolizumab.
Transmission lines are affected by the natural environment for a long time, and bolts are prone to frequent vibration, resulting in loosening or falling off. In this paper, the loose mechanism of ...transmission line threaded connection is analysed, and the transverse vibration comparative test of bolt locking method is carried out. A new type of locking nut has been developed, which has good locking performance and convenient installation. According to different operating environments, the principle of differential bolt locking is proposed.
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