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The residence time of polydisperse particles is crucial for their simultaneous conversion in a fluidized bed. This study focuses on regulating the residence time of polydisperse particles to expand their controllable range by optimizing the reactor design and operation step-by-step. The mean residence time (MRT) ratio of coarse and fine particles (tpc/tpf) increased significantly with increasing elutriation pipe width of the multiple-chamber fluidized bed, thus enabling the MRT ratio to exceed (dpc/dpf)2; however, the MRT ratio of medium and fine particles (tpm/tpf) is only slightly exceeded dpm/dpf. Moreover, by further optimizing the elutriation pipe gas velocity, the latter can be adjusted to be exceed (dpm/dpf)1.5. Finally, tpc/tpfand tpm/tpfcan be simultaneously adjusted to exceed (dp/dpf)2by increasing the number of elutriation pipes. Therefore, present study enables the controllable range of the MRT ratio of polydisperse particles covering from dp/dpf2to (dp/dpf)2that meets the required reaction time ratio of different particle sizes, which is of great interest for realizing the synchronous conversion of polydisperse particles.

Polyferrocene macrocycles hold immense potential in the fields of molecular electronics and electrochemistry, primarily due to their multiple metal centers. However, developing highly efficient synthetic strategies for constructing these rings remains a significant challenge. In this study, we successfully synthesized triferrocenyl macrocycles using Pt-mediated coupling strategy and determined their configuration using single-crystal X-ray diffraction analysis, revealing a structure reminiscent of the Penrose Stair. We comprehensively investigated the macrocycle’s structure, photophysical properties, and employed density functional theory (DFT) calculations to gain further insights. Notably, this macrocycle exhibits several advantageous features, including a flexible structure, good solubility, and a highly efficient synthetic pathway.

Glycolytic intermediary metabolites such as fructose-1,6-bisphosphate can serve as signals, controlling metabolic states beyond energy metabolism. However, whether glycolytic metabolites also play a role in controlling cell fate remains unexplored. Here, we find that low levels of glycolytic metabolite 3-phosphoglycerate (3-PGA) can switch phosphoglycerate dehydrogenase (PHGDH) from cataplerosis serine synthesis to pro-apoptotic activation of p53. PHGDH is a p53-binding protein, and when unoccupied by 3-PGA interacts with the scaffold protein AXIN in complex with the kinase HIPK2, both of which are also p53-binding proteins. This leads to the formation of a multivalent p53-binding complex that allows HIPK2 to specifically phosphorylate p53-Ser46 and thereby promote apoptosis. Furthermore, we show that PHGDH mutants (R135W and V261M) that are constitutively bound to 3-PGA abolish p53 activation even under low glucose conditions, while the mutants (T57A and T78A) unable to bind 3-PGA cause constitutive p53 activation and apoptosis in hepatocellular carcinoma (HCC) cells, even in the presence of high glucose. In vivo, PHGDH-T57A induces apoptosis and inhibits the growth of diethylnitrosamine-induced mouse HCC, whereas PHGDH-R135W prevents apoptosis and promotes HCC growth, and knockout of Trp53abolishes these effects above. Importantly, caloric restriction that lowers whole-body glucose levels can impede HCC growth dependent on PHGDH. Together, these results unveil a mechanism by which glucose availability autonomously controls p53 activity, providing a new paradigm of cell fate control by metabolic substrate availability.

For carbon nanofiber/poly(vinylidene fluoride) (CNF/PVDF) nanocomposite materials, the strong interactions between nanofillers would induce agglomeration and hence significantly deteriorate both the electromagnetic interference (EMI) shielding and thermal conductivity of materials. In this work, an effective supercritical fluid-assisted thin cell wall stretching–defoaming method was proposed to improve the nanofiller dispersion of CNF/PVDF nanocomposites. Meanwhile, the relationship between the nanofiber 3D network structure and the cell growth of foaming was studied in depth via a biaxial stretching experiment and a Monte Carlo simulation. By using this method, the nanocomposite performance was enhanced: (1) at a low filler content, the 3D stretching is beneficial for improving the nanoscale interface in nanocomposites, that is, increasing the dielectric permittivity (increased by 183.7%), decreasing the dielectric loss, and increasing the breakdown strength (increased by 87.1%), and (2) at a high filler content, the 3D stretching is beneficial for improving the macroscale network. That is, the EMI increased by 46.4% and the thermal conductivity increased by 27.3%.

Methicillin‐resistant Staphylococcus aureus(MRSA) infection and compromised immunity are the severe complications associated with implantation surgery in diabetes mellitus. Enhancing the antibacterial and immunomodulatory properties of implants represents an effective approach to improve the osseointegration of implant in diabetes mellitus. Herein, guanidination carbon dots (GCDs) with antibacterial and immunoregulatory functions are synthesized. The GCDs demonstrate killing effect on MRSA without detectable induced resistance. Additionally, they promote the polarization of macrophages from the M1 to M2 subtype, with the inhibiting pro‐inflammatory cytokines and promoting anti‐inflammatory factors. Correspondingly, GCDs are immobilized onto sulfonated polyether ether ketone (SP@GCDs) using a polyvinyl butyraldehyde (PVB) coating layer through soaking‐drying technique. SP@GCDs maintain stable antibacterial efficacy against MRSA for six consecutive days and retain the immunomodulatory function, while also possessing the long‐term storage stability and biocompatibility of more than 6 months. Moreover, SP@GCDs significantly promote the proliferation and mineralization of osteoblasts. SP@GCDs facilitate osteogenesis through immunoregulatory. Additionally, SP@GCDs exert stable antibacterial and immune regulatory functions in implantation site of a diabetes rat, effectively promoting implant osseointegration regardless of the MRSA infection. These findings provide valuable insights into implant modification through designing nanomaterials with multifunction for enhancing osseointegration of diabetes mellitus, suggesting the promising clinical application prospects. Carbon dots with the antibacterial and immunomodulatory properties are applied to modify polyether ether ketone to achieve antibacterial activity against Methicillin‐resistant Staphylococcus aureus(MRSA), immune modulation and osteoblastic properties in microenvironment for promoting osseointegration in diabetes with MRSA infection.

Our previous research showed that Naotaifang (a compound traditional Chinese herbal medicine) extract (NTE) has clinically beneficial effects on neurological improvement of patients with acute cerebral ischemia. In this study, we investigated whether NTE protected acute brain injury in rats and whether its effects on ferroptosis could be linked to the dysfunction of glutathione peroxidase 4 (GPX4) and iron metabolism.

X-ray excited photodynamic therapy (X-PDT), which utilizes X-rays as the energy source and X-ray luminescent nanoparticles (XLNPs) as the transducer to excite photosensitizers (PS), resolves the penetration problem of light in traditional PDT to enable the treatment of deep-seated tumors. Nevertheless, the high X-ray dosage used in X-PDT hampers its potential applications in clinics. In this study, to alleviate the dose problem, β-NaLuF4:Tb3+spherical nanoparticles (NPs) with ultrastrong green X-ray excited optical luminescence (XEOL) due to the less nonradiative relaxation probability and high X-ray absorption mass coefficient, which perfectly matches the absorption spectrum of a photosensitizer named rose bengal (RB), were synthesized and employed as the energy transducer for X-PDT. After covalent conjugation of NPs with RB, high Förster resonant energy transfer (FRET) efficiency up to 94.29% was achieved, leading to high production of singlet oxygen. In vivoX-PDT efficacy was evaluated by nude mice with a HepG2 tumor xenograft. With excellent biocompatibility, the synthesized NPs–RB nanocomposite showed significant antitumor efficiency up to 80 ± 12.3% with a total X-ray dose of only 0.19 Gy, demonstrating the feasibility of low-dose X-PDT in vivofor the first time. The present work provides a promising platform for X-PDT in deep-seated tumors.

1.Network nestedness describes an interaction pattern, wherein specialist species interact with a subset of partner species. Antagonistic networks are predicted to not be nested, because nestedness indicates a high intensity of interspecific competition, which compromises species coexistence. However, network nestedness is commonly observed in antagonistic networks, and the discrepancy between prediction and observation has not been fully resolved.2.One of underlying factors explaining this discrepancy is the imperfection of metrics to detect network nestedness. However, studies comparing network metrics often fail to resolve which metric works best, presumably because they lack specific criteria.3.We compared the results of the most commonly used metrics (weighted NODF) and a later proposed metric (spectral radius) to measure the nestedness of a quantitative plant - larval sawfly bipartite (including 8 sawfly species and 66 plant species, identified by gut DNA metabacoding of larvae). We also determined whether the sawfly species can coexist in terms of their dietary differences. Because nested structure is not likely to be compatible with species coexistence, we assumed that the metric identifying a non-nested structure is superior to the other.4.The two metrics led to contrasting nestedness levels. Both observational and preference networks were found to be nested using weighted NODF, but was not nested using the spectral radius approach.5.The dietary differences were significant among each sawfly species pair for both observational and preference networks, indicating low interspecific competitiveness and a high potential for species coexistence.6.These results indicate that the spectral radius metric is superior to weighted NODF to detecting network nestedness and should be used in future network studies.

To explore the feasibility and safety of using tissue-type plasminogen activator (t-PA) to prevent graft restenosis after coronary artery bypass grafting (CABG). In this prospective observational study, 37 patients underwent CABG between June 2009 and May 2013. These patients were grouped according to the anti-coagulation strategy after surgery: t-PA (n= 12) and conventional treatments (n= 25). In the t-PA group, the patients received acetylsalicylic acid (ASA) and clopidogrel plus intravenous infusion of t-PA (0.25 mg/kg/day) starting at 24 h after surgery and that lasted for 3 days. In the conventional group, the patients received only ASA and clopidogrel. 64-row spiral computed tomographic coronary angiography was performed at 1 week, 1, and 3 months after surgery to evaluate the patency of the graft vessel. The mean stenosis severity of the saphenous vein grafts was lower in the t-PA group compared with the conventional group at 3 months after surgery (p< 0.05), but there was no significant difference at 1 week and 1 month (p> 0.05). The patency rate of the grafts was not significantly different between the two groups at 1 week, 1, and 3 months after surgery (p> 0.05). Early application of t-PA after CABG was feasible and safe, and might help prevent early restenosis of SV grafts. Additional clinical randomized trials are necessary to address this issue.

This paper reports that changing metal ions (Co2+, Ni2+, Cu2+, or Cd2+) in the 2-(2-thiazolylazo)-P-cresol (TAC)-metal ensemble may generate varied optical responses to anions. The TAC and Ni2+ensemble can detect and quantify CN-in a highly sensitive and selective manner. CN-competes for the Ni2+present in the ensemble during recognition events, which thereby triggers colorimetric and absorption spectral changes. CN-and S2-decomposed TAC-Cu2+ensemble by forming [Cu(CN)X]n-species and CuS, respectively; however, the discrimination of CN-and S2-was not achieved. The TAC-Co2+ensemble exhibited discriminated interaction with CN-through the absorption channel, but CN-was not quantitatively determined. Although the TAC-Cd2+ensemble responded to different anions, it did not recognize each anion selectively. These results demonstrated that metal ions can powerfully modulate anion identification to some extent, which can be an effective strategy to achieve selectivity of certain anions by varying the metal ions in the ensemble.

The lightweight primary mirror of the four meter Chinese telescope is supported axially by a passive hydraulic system, in parallel with an active system. The figure is sensitive to the errors in the axial forces, which can be effectively corrected using active optics. The squared RMS of this figure approximately follows the χ^2 distribution, as verified by Monte Carlo analysis. The probability distributions of the squared norm of the active-forces vector, of the squared norm of the leg-lengths vector in the hexapod platform, and of the squared RMS of the residual figure are discussed in terms of the bending modes obtained by singular-value decomposition of the influence matrix, the optical sensitivity matrix deduced through ray trace, and the Jacobian matrix of the hexapod platform. The results show that, within the 90% confidence interval, the RMS of the figure caused by the axial-force errors is less than 232.38 nm and is corrected to less than 3.26 nm by the active optics. The maximum values of the corresponding squared norms of the active-force vector and of the leg-lengths vector are deduced.

We aimed to globally discover serum biomarkers for diagnosis of gastric cancer (GC). GC serum autoantibodies were discovered and validated using serum samples from independent patient cohorts encompassing 1,401 participants divided into three groups, i.e.healthy, GC patients, and GC-related disease group. To discover biomarkers for GC, the human proteome microarray was first applied to screen specific autoantibodies in a total of 87 serum samples from GC patients and healthy controls. Potential biomarkers were identified via a statistical analysis protocol. Targeted protein microarrays with only the potential biomarkers were constructed and used to validate the candidate biomarkers using 914 samples. To provide further validation, the abundance of autoantibodies specific to the biomarker candidates was analyzed using enzyme-linked immunosorbent assays. Receiver operating characteristic curves were generated to evaluate the diagnostic accuracy of the serum biomarkers. Finally, the efficacy of prognosis efficacy of the final four biomarkers was evaluated by analyzing the clinical records. The final panel of biomarkers consisting of COPS2, CTSF, NT5E, and TERF1 provides high diagnostic power, with 95% sensitivity and 92% specificity to differentiate GC patients from healthy individuals. Prognosis analysis showed that the panel could also serve as independent predictors of the overall GC patient survival. The panel of four serum biomarkers (COPS2, CTSF, NT5E, and TERF1) could serve as a noninvasive diagnostic index for GC, and the combination of them could potentially be used as a predictor of the overall GC survival rate.

The computer vision technology is an important branch of computer science and artificial intelligence which is regarded as a non-destructive testing technique in the field of agriculture with a broad application prospects. This paper introduces the application of the computer vision technology in the agricultural products deterioration recognition, builds foundations for the accurate measurement of the agricultural products quality with computer visions, and establish the relationship between the feature information and quality of the agricultural products. Meanwhile, this paper combined the computer vision technology with infrared, microwave, NMR techniques to extract and test the visual information of the internal quality of the agricultural products.

According to the internal mechanism of the formation of heat load, the formation of heat load consists of two parts, the systemic heat load, which is determined by the building envelope and outdoor environmental parameters and random load caused by the users randomness of events and solar radiation etc. Toward systemic heat load, this paper considered the influence of environmental parameters before the prediction time and used the method of stepwise trials and MSE to obtain the optimal solution. Toward random load, it is considered that the day of the same type have the same variation pattern. On this basis, this paper introduced a correction coefficient to obtain random load eventually. This paper selected DeST, the widely used energy simulation software in China, to analysis the case. The result shows that the prediction method is feasible and 50% of the predicted loads have the relative error of less than 5%.

Focusing on the phenomenon that many office buildings and student apartments in northern China with vertical single tube series heating systems are of high energy consumption and waste lots of thermal energy because of lacking heating regulation, this paper proposed a system of on-off regulation to optimize the regulation, where on-off values are installed in each vertical riser, indoor temperature controllers are installed in the room with lower temperature, and the on-off values control circulating water automatically according to the difference between the real temperature and the set temperature and finally the indoor temperatures are controlled. The temperature control effect and energy saving effect of this system were discussed in both simulation and measurement. The conclusion shows that: 1) the proposed system can optimize heating regulation and reduce the loss cause of heating non-uniformity.2) the on-off control on the flow of single vertical tube makes temperature of all rooms stringed in the riser meet the requirements.3) the indoor temperature differences in the same riser are controlled in 2 °C.4) in practical, users on-time is only 50% of total time through on-off regulation, the effect of energy saving is significant.

According to features of detection, tracking and identification technology of weak moving targets in image process, the paper simply introduces its technical difficulties and mainly discusses the detection and tracking algorithm for the weak moving targets. In accordance with three steps including the image preprocessing, feature selection and target tracking, the paper designs images' detection and tracking recognition algorithm for the weak moving objects in strong noise background, and describes the specific execution methods and procedures, which has a certain significance to further improve image detection for the weak moving targets.

It is a question if large scale heating/cooling network could be applied in China economically, environmental protection and energy saving. Toward this question, this paper studied the optimization of large scale heating and cooling network. The components of the system are analyzed and modeled in detail including heating/cooling source, heating/cooling users and transmit system. And the system can be optimized through the way of Life Cycle Cost, which compared the cost of large scale heating and cooling system with conventional system. The optimization also takes efficiency and economy in to consideration.

This paper discussed the optimization of two cases of large scale heating and cooling system. One is the heating/cooling system with heating/cooling source with distance from load center, the other is the heating/cooling system with heating/cooling source located in the load center. The affect of the temperature difference between supply and return water, load density and the price of energy towards optimized radius and max radius was discussed using the existed model. The optimized radius and appropriate system parameters are got. It is a reference to the designers and operators related.

As an advanced heat metering method, on-off valve regulation method has good temperature-control and energy-saving effects. But its hydraulic regime is different from other existing systems, the conditions are more complicated and researches are not enough. There is an opinion that differential pressure valve should be used in the buildings consumer heat inlet. For all the questions and uncertainties, this article conducted researches by field test and program simulation analysis. The field test was conducted in a housing estate in Beijing, one buildings flow regulations influence on other buildings hydraulic regime was tested. The simulation was done in HACNet hydraulic simulation software. A pipe net model was built to simulate different working conditions. Both results indicate that systems hydraulic regime is stable and differential pressure valve is not necessary.

Abstract: Analytical model is presented herein to predict the diameter of crater in semi-infinite metallic targets struck by a long rod penetrator. Based on the observation that two mechanisms such as mushrooming and cavitation are involved in cavity expansion by a long rod penetrator, the model is constructed by using the laws of conservation of mass, momentum, energy, together with the u-v relationship of the newly suggested 1D theory of long rod penetration (see Lan and Wen, Sci China Tech Sci, 2010, 53(5): 1364–1373). It is demonstrated that the model predictions are in good agreement with available experimental data and numerical simulations obtained for the combinations of penetrator and target made of different materials.

Abstract: The modified hydrodynamic theory of long rod penetration into semi-infinite targets was established independently by Alekseevskii and Tate over forty years ago and since then many investigators contributed much to the development of the high speed penetration mechanics. However, in all the models proposed so far, the target resistance R t is not well defined and usually determined by adjusting it until the predicted depth of penetration comes to an agreement with experimental data. In this paper, assumptions are first made about particle velocity and pressure profiles together with response regions in the target and then an extension is made to the modified hydrodynamic theory of long rod penetration into semi-infinite targets, in which R t has explicit form and is dependent on penetration velocity as well as thermo-mechanical properties of target material. The present model is compared with long rod penetration tests for different material combinations. It transpires that the present model predictions are in good agreement with the experimental data and numerical simulations in terms of penetration depth although many assumptions and simplifications are introduced into the paper.

A diode-laser pumped blue intracavity frequency-doubled self-Q-switched microchip laser of a chromium Cr4+Neodymium Nd3+codoped yttrium aluminum garnet crystal (Cr4+Nd3+:YAG)combined with a potassium niobate (KNbO3)crystal is developed. By coating the cavity mirrors with the films that suppress the 1064-nm operation and enhance the 946-nm laser, the 4F3/2→4I9/2transition of the Nd3+ion is facilitated to achieve the 946-nm laser oscillation. The 946-nm laser of the Cr4+Nd3+:YAGis self-Q-switched due to the saturable absorption of the Cr4+ion. The full width at half maximum (FWHM) of the laser pulse at a 964-nm wavelength is about 5.07 ns. A self-Q-switched 473-nm laser pulse is sequentially obtained through intracavity frequency doubling of the 946-nm laser by the KNbO3crystal, whose FWHM is about 4.30 ns. The 473-nm intracavity doubled laser has a good fundamental transverse TEM00mode, because the self-Q-switched 946-nm laser has a good TEM00mode that results from the absorption bleaching established by both the 808-nm pump laser and 946-nm oscillating laser. The constant FWHM results from both the response time of the self-Q-switching and the establishing time of the oscillating laser being much faster than the accumulated time of the pump laser energy. The constant peak power of the 946-nm self-Q-switched laser mainly depends on the modulation ability of the self-Q-switching. © 2004 Society of Photo-Optical Instrumentation Engineers.

Objective: The aim of the study is to determine the role of nuclear receptor coactivator 2 in cell proliferation and invasion ability of gastric cancer cells and to explore its possible mechanisms.Methods: Immunohistochemical staining was used to determine NCOA2gene expression in gastric cancer. Western blotting was used to detect Wnt signal pathways–related protein expression. Colony formation assays, Cell Counting Kit-8 assays, and transwell assays were used to determine cell proliferation, metastasis, and invasion ability of gastric cancer cells. A flow cytometric apoptosis tests determine gastric cancer cell apoptosis ability after inhibition of the expression of nuclear receptor coactivator 2. Subcutaneous mouse models were used to determine the gastric cancer growth and peritoneal metastasis differences after inhibition the expression of nuclear receptor coactivator 2.Results: The expression of nuclear receptor coactivator 2 in gastric cancer cells is high (P< .01), including lymph node metastasis, TNM staging, and gender differences in nuclear receptor coactivator 2 expression were statistically significant (P< .01). Short interfering nuclear receptor coactivator 2 could inhibit the proliferation and invasion ability of gastric cancer cells. Short interfering nuclear receptor coactivator 2 promotes the apoptosis of gastric cancer cells. Animal experiments showed that short interfering nuclear receptor coactivator 2 could inhibit the growth and invasion of gastric cancer-transplantable tumors. Knockdown of the expression of nuclear receptor coactivator 2 inhibited the Wnt/β-catenin signaling pathway in the gastric cancer cells.Conclusions: Knockdown of the expression of nuclear receptor coactivator 2 can inhibit the proliferation and invasion of human gastric cancer in vitroand in vivo. The underlying mechanism of NOCA2 affects the Wnt signaling pathway.

In this paper, a class of two-level high-order compact finite difference implicit schemes are proposed for solving the Burgers' equations. Firstly, based on the fourth-order compact finite difference schemes for spatial derivatives and the truncation error remainder correction method for temporal derivative, the high-order compact (HOC) difference method is introduced for solving the one-dimensional (1D) Burgers' equation. At the same time, the stability of the scheme is analyzed by using the Fourier analysis method. Because only three grid points are involved in each time level. The Thomas algorithm can be directly used to solve the tridiagonal linear system. Then, this method is extended to solve the two-dimensional (2D) and three-dimensional (3D) coupled Burgers' equations. Finally, numerical experiments are conducted to verify the accuracy and the reliability of the present schemes. [ABSTRACT FROM AUTHOR]