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Alliances are essential for high-tech startups that are seeking resources and preparing for future expansion. This study examines how the attributes of high-tech startups’ early-stage inventions influence the likelihood of forming alliances. Specifically, we explore the impact of technological novelty and economic scope of inventions on alliance formation. Using a sample of 408 healthcare startups, we empirically demonstrate that technological novelty has a negative impact on alliance formation, whereas economic scope has a positive impact. We also find that the engagement of corporate venture capitalists can mitigate the negative impact of technological novelty on high-tech startups’ alliance formation. [ABSTRACT FROM AUTHOR]

Meerwein-Ponndorf-Verley (MPV) reduction has gained much attention due to is mid reaction conditions, and this reaction can be performed without the presence of reductive atmosphere and the reaction conditions of high temperature and high pressure. Solid bases with abundant strong basic sites can be synthesized with metal-organic frameworks (MOFs) as precursors. These MOFs are immobilized with alkane metal nitrides, followed by calcination to produce the desired basic metal oxides. The basic zirconia shows highly efficient catalytic performance in MPV reduction of substrates with the carbonyl group, and benzaldehyde can be completely reduced in 6 hours with a mild reaction temperature (160 °C) in the absence of hydrogen gas. The catalytic efficiency is determined by the amounts of strong basic sites, but not the total amounts of basic sites, and this phenomenon is proved by the contrast experiments with the catalytic test of weak solid bases. Furthermore, the cooperative action between basic and acid sites can also enhance the catalytic performance in MPV reactions. With MOFs as precursors, metal oxide catalysts can be synthesized with well dispersed active sites. [ABSTRACT FROM AUTHOR]

HVDC auxiliary emergency power control can improve the transient stability of AC/DC power system. Compared with other control methods, HVDC auxiliary emergency power control has the advantages of quick response, large adjustment capacity and less investment, so it is the primary choice to improve the transient stability. Taking multi-infeed DC (MIDC) transmission system as the research object, based on the definition of the traditional power support factor, considering the influence of the electrical connection of the sending-end power grid on the power support, a new power support factor (NPSF) is defined. Based on the NPSF, multiple DC coordination sharing strategies are implemented when one of the DC faults occurs. Finally, MIDC is built on the PSCAD. Single DC auxiliary power control and multiple DC auxiliary power coordinated control were simulated, respectively. Rationality of the definition of NPSF is verified, and it is concluded that multiple DC joint power control is superior to single DC. [ABSTRACT FROM AUTHOR]

A novel high‐voltage direct‐current (HVDC) line fault location method based on phase frequency change characteristics is proposed. The idea of the method is the travelling waves for the fault happened on different positions have different phase distortion characteristics, when they spread to the measuring terminal. By using the discrete Fourier analysis, the phase frequency characteristics were obtained. The frequency data of 40 to 60 Hz and the corresponding phase angle ratio data are selected, forming a N × 3 matrix, each row of data represents the relationship between the fault location and phase angle ratio, fitting each row of data, respectively, the mathematical relationship between the fault location and phase angle ratio can be obtained, finally realise DC line fault location by seeking average. Finally, a lot of different faults are simulated and analysed on the PSCAD platform to verify the effectiveness and robustness of the proposed method. [ABSTRACT FROM AUTHOR]

Notum, which belongs to the α/β hydrolase family, is a deacylated extracellular protein that regulates the Wnt signaling pathway. Studies have found that Notum participates in the progression of colorectal cancer and hepatocellular carcinoma, but its role in oral squamous cell carcinoma (OSCC) is currently unclear. This study aimed to explore the role of Notum in regulating OSCC and further reveal the underlying mechanisms. Various approaches including bioinformatics analysis, enzyme-linked immunosorbent assay and immunohistochemical staining were used to detect the expression of Notum in OSCC cells and tissues. Cell counting kit-8 assay, clone formation assay, wound healing assay, transwell assay and in-gel zymography assay were explored to evaluate the regulation of Notum in OSCC proliferation and migration. Hoechst 33342/PI assay, cell immunofluorescence, flow cytometry and in vivo tumorigenesis experiment were applied for OSCC apoptosis. Real-time quantitative polymerase chain reaction analysis was performed for mRNA level while western blotting was conducted to detect protein expression. The results showed that Notum was highly expressed in OSCC tissues and cells, and Notum promoted the proliferation and migration of OSCC cells while it inhibited their apoptosis. Furthermore, signaling pathway analysis showed that Notum led to potential pro-survival of OSCC through crosstalk between sonic hedgehog (Shh) and Wnt/β-catenin signaling via phosphorylation of glycogen synthase kinase-3 beta. These results will help to elucidate the mechanism and also provide new ideas for targeted treatment of OSCC. [ABSTRACT FROM AUTHOR]

Objective: Periostin is important for the maintenance of periodontal tissue, but its role in periodontitis is controversial. This research investigated the effect of periostin in periodontitis and the underlying mechanism. Design: Mouse periodontitis models in vivo and inflammation model in vitro which were induced by Porphyromonas gingivalis lipopolysaccharide were established to evaluate periostin expression. Human periodontal ligament fibroblasts (PDLFs) were treated with lipopolysaccharide and N‐acetylcysteine, fluorescence staining, flow cytometry, Western blot, and qRT‐PCR were used to detect reactive oxygen species (ROS), periostin expression, and apoptosis‐related makers. The periostin gene was successfully transfected into PDLFs to verify the effect of periostin on apoptosis. Then, the Nrf2 inhibitor was added to clarify the mechanism. Results: Periostin expression decreased in the periodontal ligaments of mouse periodontitis models and lipopolysaccharide‐induced PDLFs. Lipopolysaccharide promoted the activation of ROS and apoptosis in PDLFs, whereas N‐acetylcysteine reversed this condition. Overexpression of periostin suppressed apoptosis of PDLFs and reversed the inhibitory effect of lipopolysaccharide on nuclear Nrf2 expression. Moreover, the Nrf2 inhibitor attenuated the protective effect of periostin on lipopolysaccharide‐induced apoptosis. Conclusions: Lipopolysaccharide induced apoptosis in PDLFs by inhibiting periostin expression and thus Nrf2/HO‐1 pathway, indicating that periostin could be a potential therapeutic target for periodontitis. [ABSTRACT FROM AUTHOR]

This article is an examination of how investors in the corporate bond market in emerging economies react to patents. To empirically explore this question, we constructed a sample of 1862 Chinese corporate bonds issued between 2004 and 2020 and gathered data on Chinese domestic patents, reverse innovation patents, and the validity of patents. The empirical results suggest that domestic patents are the primary source of information for bond investors in China when evaluating corporate innovation and that investors can successfully discern between patents that are valid and those that are not. At the same time, the positive relationship between corporate innovation and bond prices is found to be negatively moderated by credit ratings and state ownership. [ABSTRACT FROM AUTHOR]

Abstract: We in-detail investigated the profile evolution processes of highly ordered alumina under the cyclic treatment of mild anodizing of aluminum foils in oxalic acid followed by etching in phosphoric acid. With the cyclic times increasing, the profiles of nanopores were gradually evolved into the parabola-like, trumpet-like and conical shape. Although the inserted etching itself nearly had no impact on the growth rate of the nanopores due to the rapid recovering of thinned barrier layer at the initial stage of next anodizing, overmuch etching could bring apparent side effects such as wall-breaking, thinning and taper-removing from the top down. The anodizing and etching kinetics and their synergetic effects in modulating different aspect ratios and open sizes of conical pores were studied systematically. These findings are helpful to tailor high-quality anodic alumina taper-pores with tunable profiles. [Copyright &y& Elsevier]

• The polypeptide OP 3-4 promoted bone regeneration of mandibular defect. • OP 3-4 improved osteogenic differentiation of bone marrow mesenchymal stem cells. • OP 3-4 promoted osteogenic differentiation by AKT/GSK3β/β-catenin pathway. The aims of this study were to explore: (ⅰ) the effect of the polypeptide OP 3-4 on bone regeneration in vivo ; (ⅱ) the effect of OP 3-4 on osteogenic differentiation of bone marrow mesenchymal stem cells in vitro ; and (ⅲ) the potential mechanism of OP 3-4 in promoting osteogenic differentiation of bone marrow mesenchymal stem cells. 30 Wistar rats (8-week, male) were randomly divided into Control group (n = 5), Hydrogel group (n = 5), and Hydrogel loaded OP 3-4 group (n = 5). Hematoxylin and eosin staining was used to evaluate the level of bone regeneration in mandibular defect. Immunohistochemistry staining was used to evaluate the expression of alkaline phosphatase, runt-related transcription factor 2, and type Ⅰ collagen. Flow cytometry was applied to identify the phenotype of bone marrow mesenchymal stem cells. Furthermore, LY294002, the inhibitor of protein kinase B, was applied to verify the role of OP 3-4 in promoting osteogenic differentiation via protein kinase B/glycogen synthase kinase 3β/β-catenin pathway through western blot. OP 3-4 promoted bone regeneration of rat mandibular defect. The expression of osteogenic differentiation related markers were increased after adding OP 3-4 to bone marrow mesenchymal stem cells. OP 3-4 promoted osteogenic differentiation of bone marrow mesenchymal stem cells via protein kinase B/glycogen synthase kinase 3β/β-catenin pathway. OP 3-4 could promote bone regeneration of mandibular defect and improve osteogenic differentiation through protein kinase B/glycogen synthase kinase 3β/β-catenin pathway. [ABSTRACT FROM AUTHOR]

• Notum expression increased in gingival tissues. • Notum expression increased in periodontal ligament. • Notum inhibited human periodontal ligament stem cell (hPDLSC) osteogenesis. • Notum regulated hPDLSC osteogenesis through Wnt/beta-catentin signaling. The aims of this study were to explore: (ⅰ) the effect of Notum on periodontitis in vivo ; (ⅱ) the effect of Notum on the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) in vitro ; and (ⅲ) the potential mechanism of Notum in inhibiting the osteogenic differentiation of hPDLSCs. C57BL/6J mice were randomly assigned into two groups: control group (n = 4) and periodontitis group (n = 4). Immunohistochemical staining was used to evaluate the expression of Notum. In in vitro experiments, Western blot, qRT- PCR and ELISA were used to examine the expression of Notum in a lipopolysaccharide-induced inflammation model. Alkaline phosphatase staining was used to evaluate alkaline phosphatase activity. Western blot and qRT - PCR were used to measure the expression of osteogenic-related markers after adding human recombinant Notum and Notum inhibitor ABC99. In addition, LiCl, an agonist of the Wnt/Beta-catenin signaling pathway, was added to explore using Western blot whether Notum was involved in regulating the osteogenic differentiation of human periodontal ligament stem cells through the Wnt/Beta-catenin signaling pathway. Notum was highly expressed in periodontal tissues of mice and lipopolysaccharide-induced inflammation cell model. The protein and messenger ribonucleic acid levels of hPDLSCs osteogenic markers were reduced after adding human recombinant Notum. However, the inhibitory effect of Notum on the osteogenic differentiation of hPDLSCs could be significantly reversed by adding LiCl. These results demonstrated that Notum inhibited the osteogenic differentiation of hPDLSCs probably via the Wnt/Beta-catenin the downstream signaling pathway. [ABSTRACT FROM AUTHOR]

• A coordinated restoration model is proposed for power-gas-transportation distribution systems. • Repair crews and energy hubs are simultaneously optimized to enhance post-disaster resilience. • Spatial interdependency between power-gas systems and transportation systems is considered to ensure the feasibility of the obtained restoration decisions. • Modified Boolean logic equations are proposed to represent the spatial interdependency. Recently, extreme events have caused widespread blackouts over energy systems. In addition, the increasing interactions between power distribution networks and natural gas networks bring new challenges to the fast recovery of energy systems. Mobile emergency resources, such as repair crews (RCs), play an essential role in the restoration. However, power distribution networks and gas networks have geographical correlations with transportation systems in urban areas, therefore, there exists spatial interdependency between infrastructural systems. This property results in the dependency between RCs' routings and road states in transportation systems. To this end, this paper proposes a sequential restoration model for power-gas-transportation distribution networks. The post-disaster restoration model contains the dispatch of both RCs and fixed resources. The spatial interdependency is modeled by modified Boolean logic equations to obtain feasible recovery schedules in practice. Convex relaxations and linearization methodologies are utilized to transform the proposed model into a mixed-integer second-order cone programming (MISOCP) model. Simulations are carried out on 33–14–20 and 136–20–39 bus coupled systems. Numerical results indicate that the proposed restoration strategy could increase the post-disaster resilience index by 19.5 % in 33-bus power system, 8.7 % in 136-bus power system, 25.6 % in 14-node gas system, and 27.2 % in 20-node gas system, respectively. [ABSTRACT FROM AUTHOR]

The grid connection of wind farms affects the load flow of a power system and may introduce an unexpected threat to the power system small signal stability. This study presents an application of probabilistic eigenvalue sensitivity indices (PSIs) for optimal allocation of wind farm in a power system. For this purpose, firstly, probabilistic sensitivity indices are used to identify the strongly correlated electromechanical eigenvalues of generators and to facilitate the wind farm site selection. Two different cases are studied, wind farm replacing synchronous generators or being directly added to the power system. Afterwards, the influence of the wind farm location on power system small signal stability is examined. For this purpose, an index is proposed to measure the small signal stability of the system and is used for optimal allocation of the wind farm. Two examples, i.e. a 3‐machine 9‐bus and an 8‐machine 24‐bus power system, with a wind farm integrated based on PSIs are presented to demonstrate the proposed approach by employing the eigenvalue analysis and a dynamic time‐domain simulation. Finally, the results are compared with the traditional optimal allocation of a wind farm for power loss reduction. [ABSTRACT FROM AUTHOR]

In order to solve the coordinated optimization problem of distributed generation (DG), on‐load tap changer (OLTC) and capacitor banks, a dynamic reactive power optimization (DRPO) method based on fuzzy time clustering is proposed. In the method, fuzzy time clustering algorithm is used to cluster the static optimal switching sequence of OLTC and capacitor banks. The time decoupling of control variables is realized and it meets the constraints of the maximum switching times. Next, the influencing factors of DG reactive power limit are analysed. Considering the control ability of OLTC, capacitor banks and DG in voltage and reactive power optimization, a coordinated optimization method is proposed. Since the adjustment of OLTC tap position directly affects the voltage and reactive power distribution of the whole line, the switching time and tap position of OLTC are determined based on the static optimization results of each time and fuzzy time clustering algorithm. Then, the switching time of capacitor banks is determined by fuzzy time clustering algorithm. At last, the switching capacity of capacitor banks and DG reactive power are jointly optimized to get the final control scheme. The proposed method demonstrated good performance in the modified IEEE33 node system and two actual power grid examples. [ABSTRACT FROM AUTHOR]

Background: The incidence of diabetic osteoporosis is increasing. This article evaluates the effect of combination treatment with the hypoglycemic drug exendin-4 (Ex-4) and the vitamin D analog eldecalcitol (ED-71) on improving diabetic osteoporosis and explores the relevant mechanism of action. Method: Micro-CT, HE staining, immunohistochemistry, qPCR and ELISA were used to evaluate the impact of Ex-4 and ED-71 on bone formation and macrophage polarization in a mouse model of diabetic osteoporosis in vivo. Immunofluorescence, flow cytometry and qPCR were used to characterize the polarization type of macrophages treated with Ex-4 and ED-71 in vitro. A co-culture system of BMSCs and macrophages was established. Subsequently, crystal violet staining, alkaline phosphatase staining and alizarin red staining were used to evaluate the migration and osteogenesis differentiation of BMSCs. Results: Ex-4 combined with ED-71 significantly reduced blood glucose levels and enhanced bone formation in mice with diabetic osteoporosis. In addition, Ex-4 synergized with ED-71 to induce the polarization of macrophages into M2 through the PI3K/AKT pathway. Macrophages treated with the combination of Ex-4 and ED-71 can significantly induce the osteogenic differentiation of BMSCs. Conclusion: Ex-4 synergized with ED-71 to reduce blood glucose levels significantly. And this combination therapy can synergistically induce osteogenic differentiation of BMSCs by promoting M2 macrophages polarization, thereby improving diabetic osteoporosis. Therefore, the combination of Ex-4 and ED-71 may be a new strategy for the treatment of diabetic osteoporosis. [ABSTRACT FROM AUTHOR]

The well-developed unified power flow controller (UPFC) has demonstrated its capability in providing voltage support and improving power system stability. The objective of this paper is to demonstrate the capability of the UPFC in mitigating oscillations in a wind farm integrated power system by employing eigenvalue analysis and dynamic time-domain simulation approaches. For this purpose, a power oscillation damping controller (PODC) of the UPFC is designed for damping oscillations caused by disturbances in a given interconnected power system, including the change in tie-line power, the changes of wind power outputs, and others. Simulations are carried out for two sample power systems, i.e., a four-machine system and an eight-machine system, for demonstration. Numerous eigenvalue analysis and dynamic time-domain simulation results confirm that the UPFC equipped with the designed PODC can effectively suppress oscillations of power systems under various disturbance scenarios. [ABSTRACT FROM AUTHOR]

The following aspects were reviewed: the development status of wind and solar hybrid power generation, the research method on power system low frequency oscillation, the influence of power system small signal stability with integration of wind and solar hybrid power, as well as improving the control strategy of stability of wind and solar hybrid power generation. Therefore, the research direction of the future low frequency oscillation analysis and control could be obtained as follow: the study of the dynamic characteristics of wind turbine and the interaction of traditional power system dynamic characteristic; the influence of wind and solar hybrid system capacity and the corresponding energy storage system on the low frequency oscillation characteristics; the influence factors of wind and solar hybrid power generation system on the damping characteristics of the interconnected systems; the design and parameter optimization of the controller to improve the damping characteristics of the system with integration of wind and solar hybrid power generation. [ABSTRACT FROM AUTHOR]

Eldecalcitol (ED-71) is a new type of vitamin D analog, and vitamin D has been reported to have therapeutic effects in infectious disease, autoimmune disease, and cancer. However, the anti-cancer effect of ED-71 remains unclear. The objective of this study was to explore the anti-cancer effect of ED-71 in human osteosarcoma cells and to identify the related mechanism. The CCK8 assay results showed that ED-71 inhibited MG-63 cell viability in dose and time dependent manners. Cloning and Transwell invasion assays showed that ED-71 inhibited clonal and invasion ability of MG-63 cells. Flow cytometry results showed ED-71 the G2/M cycle arrest rate, apoptosis, and intracellular ROS. Western blot was used to detect cleaved-caspase-3, Bax, Bcl-2, LC3-II/LC3-I, and P62 levels and the mTOR pathway. The increase of LC3-II and P62 indicated that ED-71 induced the formation of autophagosomes and inhibited autophagy flux. Furthermore, ED-71-induced apoptosis was weakened after adding 3-methyladenine and ED-71-induced early autophagy was weakened by caspase-3 inhibitor (Z -VAD-FMK), which indicated the two processes active each other in the presence of ED-71. Furthermore, N-acetylcysteine (NAC) pretreatment reversed the ED-71-treatment outcomes, including increased apoptosis and autophagy and inhibition of the PI3K/Akt/mTOR pathway. In conclusion, our results reveal that ED-71 induced G2/M arrest, apoptosis and autophagy in MG-63 cells by accumulating ROS to suppress the PI3K/Akt/mTOR signaling pathway • ED-71 induced early autophagy and apoptosis in MG-63 cells. • Autophagy induced by ED-71 lead to cell death rather than survival by inducing apoptosis. • Autophagy and apoptosis induced by ED-71 promoted each other. • Autophagy and apoptosis induced by ED-71 were regulated by accumulating ROS to suppress the PI3K/Akt/mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Aldol condensation between furfural (FA) and MIBK is used to synthesize branched bio-jet-fuel precursors. It remains difficult to design hybrid solid bases to efficiently promote this reaction, because only strong basic sites can activate MIBK. Different basic species were immobilized into zirconia/carbon hybrid supports by thermal decomposition of GO/UiO materials loaded with corresponding alkane (earth) nitrides. Only Cs immobilized zirconia/carbon (CsZC) could efficiently promote this reaction, while counterparts with Li, Mg and Ca species showed little activity over condensation between MIBK and FA. Optimized CsZC showed excellent FA conversion and selectivity towards desired products (88.6% in yields of FMIBK in 6 h at 130 °C). Two indirect proofs were provided to check the influence of basic strength on the catalytic performance, and only Cs samples had enough strong basic sites to accelerate the reaction. After modified with octyl groups, hydrophobic CsZC were reused for 4th cycle while retaining most of its original activity. Functionalization with organosilanes increased the hydrophobicity of the surface, which had dramatical promotion on activity, selectivity, and stability. It was the first time to run recycling experiments for this reaction, to afford the demands for chemical sustainability. Cs immobilized zirconia/carbon hybrid solid bases (CsZC) were synthesized by thermal decomposition of CsNO 3 loaded GO/zirconium MOFs. CsZC could efficiently catalyze aldol condensation of furfural and MIBK to produce bio-jet-fuel precursors, and catalytic stability was greatly promoted by hydrophobic modification of CsZC with octyl groups. Unlabelled Image [ABSTRACT FROM AUTHOR]