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Purpose:: The purpose of this study is to investigate the performance of out-of-time events (OoT events) in the Follow-up X-ray Telescope (FXT) onboard the Einstein Probe. The OoT events, registered on the PN-CCD during its readout time, can provide information on the sources, e.g., spectral indices, and diagnose the behavior of pile-up. Methods:: In order to analyze the characteristics of OoT events, we simulated sources, each of which had been modeled using an absorbed power law combined with Gaussians, in different FXT modes and different luminosities. This allowed us to determine the OoT spectral indices and pile-up effect. Results:: In the timing mode of FXT, the OoT events occupy a large proportion and the OoT correction must be done with the assumption that all photons originate from the source position on the CCD. While for some bright sources, the OoT events may be sufficient to derivate the source spectra, especially when pile-up occurs, particularly in the full frame mode and the partial window mode of FXT. Conclusion:: We conclude that the OoT events can provide additional information about the celestial sources and can be used to estimate whether the pile-up occurs or not and the scope of pile-up. Furthermore, they can be also used to determine the new sources and improve the detection significance of a source.

Immunotherapy targeting the toll-like receptor 7 (TLR7) is a promising strategy for cancer treatment. Herein, we describe the design and synthesis of a series of imidazoquinoline-based TLR7 agonists and assess NF-κB pathway activation using HEK-Blue hTLR7 cells to identify the most potent small-molecule TLR7 agonist, SMU-L11(EC50= 0.024 ± 0.002 μM). In vitroexperiments demonstrated that SMU-L11specifically activated TLR7, resulting in recruitment of the MyD88 adaptor protein and activation of the NF-κB and MAPK signaling pathways. Moreover, SMU-L11was found to exert immune-enhancing effects by significantly inducing the secretion of proinflammatory cytokines in murine dendritic cells, macrophages, and human peripheral blood mononuclear cells while promoting M1 macrophage polarization. In vivostudies using a B16-F10 mouse tumor model showed that SMU-L11significantly enhanced immune cell activation and augmented CD4+T and CD8+T-cell proliferation, directly killing tumor cells and inhibiting tumor growth.

Abstract: Monodisperse and spherical Eu-doped TiO2 nanodots were prepared on substrate by phase-separation-induced self-assembly. The average diameters of the nanodots can be 50 and 70 nm by changing the preparation condition. The calcined nanodots consist of an amorphous TiO2 matrix with Eu3+ ions highly dispersed in it. The Eu-doped TiO2 nanodots exhibit intense luminescence due to effective energy transfer from amorphous TiO2 matrix to Eu3+ ions. The luminescence intensity is about 12.5 times of that of Eu-doped TiO2 film and the luminescence lifetime can be as long as 960 μs.

Surface potential is rarely investigated as an independent factor in influencing tissue regeneration on the metal surface. In this work, the surface potential on the titanium (Ti) surface was designed to be tailored and adjusted independently, which arises from the ferroelectricity and piezoelectricity of poled poly(vinylidene fluoride-trifluoroethylene) (PVTF). Notably, it is found that such controllable surface potential on the metal surface significantly promotes osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro as well as bone regeneration in vivo. In addition, the intracellular calcium ion (Ca2+) concentration measurement further proves that such controllable surface potential on the metal surface could activate the transmembrane calcium channels and allow the influx of extracellular Ca2+into the cytoplasm. That might be the reason for improved osteogenic differentiation of BMSCs and bone regeneration. These findings reveal the potential of the metal surface with improved bioactivity for stimulation of osteogenesis and show great prospects for fabricable implantable medical devices with adjustable surface potential.

Full-thickness skin wounds are have continued to be reconstructive challenges in dermal and skin appendage regeneration, and skin substitutes are promising tools for addressing these reconstructive procedures. Herein, the one-step fabrication of a cell sheet integrated with a biomimetic hydrogel as a tissue engineered skin for skin wound healing generated in one step is introduced. Briefly, cell sheets with rich extracellular matrix, high cell density, and good cell connections were integrated with biomimetic hydrogel to fabricate gel + human skin fibroblasts (HSFs) sheets and gel + human umbilical vein endothelial cells (HUVECs) sheets in one step for assembly as a cell sheet-laden hydrogel (CSH). The designed biomimetic hydrogel formed with UV crosslinking and ionic crosslinking exhibited unique properties due to the photo-generated aldehyde groups, which were suitable for integrating into the cell sheet, and ionic crosslinking reduced the adhesive force toward the substrate. These properties allowed the gel + cell sheet film to be easily released from the substrate. The cells in the harvested cell sheet maintained excellent viability, proliferation, and definite migration abilities inside the hydrogel. Moreover, the CSH was implanted into a full-thickness skin defects to construct a required dermal matrix and cell microenvironment. The wound closure rate reached 60.00 ± 6.26% on the 2nd day, accelerating mature granulation and dermis formation with skin appendages after 14 days. This project can provide distinct guidance and strategies for the complete repair and regeneration of full-thickness skin defects, and provides a material with great potential for tissue regeneration in clinical applications.

Electrical stimulation (ES) has been considered a promising strategy in regulating intracellular communication, membrane depolarization, ion transport, etc. Meanwhile, cell topography, such as the alignment and elongation in anisotropic orientation, also plays a critical role in triggering mechanotransduction as well as the cellular fate. However, coupling of ES and cell orientation to regulate the polarization of macrophages is yet to be explored. In this work, we intended to explore the polarization of macrophages on a poly(vinylidene fluoride-trifluoroethylene [P(VDF-TrFE)] film with intrinsic microstripe roughness, which was covered on indium tin oxide planar microelectrodes. We found that mouse bone marrow-derived macrophages (BMDMs) cultured on a P(VDF-TrFE) film exhibited an elongated morphology aligned with the microstripe crystal whisker, but their polarization behavior was not affected. However, the elongated cells were susceptible to ES and upregulated their M2 polarization, as verified by the related expression of phenotype markers, cytokines, and genes, while not affecting M1 polarization. This is due to the increased expression of the M2 polarization receptor interleukin-4Rα on the surface of elongated BMDMs, while the M1 polarization receptor toll-like receptor 4 was not affected. Thus, M2 polarization was singularly enhanced after activation of polarization by ES. The combination of surface morphology and ES to promote M2 single polarization in this work provides a new perspective for regulating macrophage polarization in the field of immunotherapy.

Osteoimmunomodulation has been considered to play a key role in osteointegration of orthopedic biomaterials. However, regulation of the macrophage phenotype in vivo with a spatiotemporal controllable way still remains a challenge. In this study, we designed a novel magnetic-responsive mineralized collagen coating to exert remotely controlled magneto-mechanical stimulation on macrophages using an external magnetic field. The magneto-mechanical stimulation exhibited immunomodulatory capability to activate M2 macrophage polarization via triggering the integrin-related cascade pathway and suppressing the phosphorylation of JNK in the MAPK pathway. The optimized inflammatory microenvironment subsequently promoted the osteogenic differentiation of bone marrow-derived mesenchymal stem cells and the osteointegration in vivo. This work, therefore, provides a remote spatiotemporal controllable strategy to promote the osteointegration of orthopedic biomaterials via regulation of the osteoimmune microenvironment.

Surface potentials of biomaterials have been shown to regulate cell fate commitment. However, the effects of chirality-patterned potential distribution on macrophage polarization are still only beginning to be explored. In this work, we demonstrated that the chirality-patterned potential distribution of CoFe2O4/poly(vinylidene fluoride-trifluoroethylene) (CFO/P(VDF-TrFE)) films could significantly down-regulate the M1 polarization of bone marrow-derived macrophages (BMDMs). Specifically, the dextral-patterned surface potential distribution simultaneously up-regulated the expression of M2-related markers of BMDMs. The results were attributed to the sensitive difference of integrin subunits (α5β1and αvβ3) to the dextral- and sinistral-patterned surface potential distribution, respectively. The interaction difference between the integrin subunits and surface potential distribution altered the cell adhesion and cytoskeletal structure and thereby the polarization behavior of BMDMs. This work, therefore, emphasizes the importance of chirality of potential distribution on cell behavior and provides a new strategy to regulate the immune response of biomaterials.

To overcome the disadvantages of inhomogeneous microstructures and poor mechanical properties of additively manufactured Ti-6Al-4V alloys, a novel technique of hybrid deposition and synchronous micro-rolling is proposed. The micro-rolling leads to equiaxed prior β grains, thin discontinuous intergranular α, and equiaxed primary α, in contrast to the coarse columnar prior β grains without the application of micro-rolling. The recrystallization by micro-rolling results in discontinuous intergranular α via the mechanism of strain and interface-induced grain boundary migration. The evolution of α globularization, driven by a solute concentration gradient, starts from the sub-boundary until the formation of equiaxed primary α. Simultaneous strengthening and toughening are achieved, which means an increase in yield strength, ultimate tensile strength, fracture elongation, and work hardening rate. The formation of α recrystallization leads to more fine grain boundaries to strengthen the yield strength, and the improvement of ductility is due to the better-coordinated deformation ability of discontinuous intergranular α and equiaxed primary α. As a result, the fracture mode in micro-rolling changes from intergranular type to transgranular type.

Dynamic regulation of cell-extracellular matrix (ECM)-material interactions is crucial for various biomedical applications. In this study, a light-activated molecular switch for the modulation of cell attachment/detachment behaviors was established on monolayer graphene (Gr)/n-type Silicon substrates (Gr/Si). Initiated by light illumination at the Gr/Si interface, pre-adsorbed proteins (bovine serum albumin, ECM proteins collagen-1, and fibronectin) underwent protonation to achieve negative charge transfer to Gr films (n-doping) through π-π interactions. This n-doping process stimulated the conformational switches of ECM proteins. The structural alterations in these ECM interactors significantly reduced the specificity of the cell surface receptor-ligand interaction (e.g., integrin recognition), leading to dynamic regulation of cell adhesion and eventual cell detachment. RNA-sequencing results revealed that the detached bone marrow mesenchymal stromal cell sheets from the Gr/Si system manifested regulated immunoregulatory properties and enhanced osteogenic differentiation, implying their potential application in bone tissue regeneration. This work not only provides a fast and feasible method for controllable cells/cell sheets harvesting but also gives new insights into the understanding of cell-ECM-material communications.

The COVID-19 pandemic has accelerated the trend of digital transformation (DT) among businesses. DT redefines business models, which significantly changes employees' work practices. If employees lack an appropriate mindset for DT, it can result in DT failure. However, little research has explored the intention of employees to embrace DT. This study proposes a dilemmatic dual-factor research model to examine the factors influencing employees' acceptance of DT, including management support and resistance to change in the outer/explicit aspect and perceived benefits and inertia in the inner/tacit aspect. The study found that the perceived benefits of DT positively impact employees' intention to accept DT, but resistance to change and perceived inertia are significant barriers. Moreover, management support alone is insufficient to encourage employees to accept DT. This study is distinct from prior research, which typically focuses on successfully implementing DT from the firm's perspective. Instead, the study offers valuable insights into promoting employee acceptance of DT.

Background:Mobile app has been used to improve exercise adherence and outcomes in populations with different health conditions. However, the effectiveness of mobile app in delivering home-based rehabilitation program to elderly patients with hip fracture is unclear.Objective:The aim of this study was to test the effectiveness of mobile app in delivering home-based rehabilitation program for improving functional outcomes and reducing caregiver stress with enhancing adherence among the elderly patients with hip fracture.Methods:A randomized controlled trial with an intervention period of two months was performed. Eligible participants were randomized into either experimental group with home-based rehabilitation program using a mobile app or control group with home-based rehabilitation program using an exercise pamphlet. Primary outcomes were Modified Functional Ambulatory Category (MFAC), Elderly Mobility Scale (EMS) and Lower Extremity Functional Scale (LEFS). Secondary outcomes were exercise adherence and Modified Caregiver Strain Index (M-CSI). The outcomes were collected at pre-discharge training session, one month and two months after hospital discharge.Results:A total of 50 participants were enrolled, with 19 participants in the experimental group and 20 participants in the control group. Eleven participants had withdrawn from the study. The experimental group showed higher exercise adherence than the control group in first month (p=0.03). There were no between-group differences in MFAC, EMS, LEFS and M-CSI at the first month and second month.Conclusion:Use of the mobile app improved exercise adherence, yet it did not improve physical performance, self-efficacy and reduce caregiver stress when compared to a standard home rehabilitation program for elderly patients with hip fracture. Further studies to investigate the benefits of mobile apps are required. (ClinicalTrials.gov ID: NCT04053348.)

Since late 2019, coronavirus disease 2019 (COVID-19) has led to a significant increase in the demand for medical resources. To publish data on face mask supplies, the Taiwanese government collaborated with program developers to construct a mask-supply information transitional platform (MITP). To comprehend the adoption of MITP, the study proposes a research model that integrates the health behavior model (HBM) and IS/IT continuance model for examining the factors affecting intention to use an MITP. Survey data collected from 524 respondents indicated that (1) intention to use an MITP is directly influenced by perceived threat of COVID-19 and beliefs toward using the MITP; (2) cues to action directly influence the perceived threat of COVID-19; and (3) perceived ease of use of MITP is a significant determinant of perceived usefulness of MITP. These results provide practical guidelines for health authorities and government to develop health information systems and strategies to control pandemics.

Cysteine (Cys) plays an important role in many physiological activities of human beings. Various diseases are always accompanied by abnormal levels of Cys. A series of Cys-responsive probes were recently developed. However, most fluorescent probes have many disadvantages and exhibit poor in vivoimaging. Therefore, a near-infrared fluorescence (NIRF)/photoacoustic (PA) dual-mode probe with high selectivity and sensitivity (limit of detection = 10.6 nM) toward Cys was developed in this study. The new Probe I interacted with Cys to activate NIRF/PA signals, detecting Cys in vitrowith a large emission wavelength (851 nm) and Stokes shift (191 nm), monitoring the occurrence of liver cancer in vivo. This work not only presented an effective NIRF/PA dual-mode dicyanoisophorone probe for the first time in the imaging of Cys but also provided a comprehensive and accurate tool for detecting different analytes and tumors in deeper tissues, which could be conducive to the early diagnosis of diseases.

To address the problems of coarse columnar grains, inhomogeneous microstructure, and anisotropic mechanical properties of Ti-6Al-4V manufactured by wire and arc additive manufacturing (WAAM) and hybrid additive manufacturing with plasma-arc deposition, synchronous microrolling (HDMR) was examined in this study. HDMR leads to significant grain refinement and isotropy improvement. Unrolled additive manufacturing alloys show typical columnar grains, while the microrolled ones show a transition from columnar to equiaxed grains with the fraction depending on the microrolling force. The microrolling-induced formation of equiaxed grains is caused by both dendrite fragmentation and prior β recrystallization in the subsequent deposition. Interestingly, the rolling force required for good grain refinement in HDMR is much lower than that in WAAM with subsequent cold rolling. Microstructure characteristics are present near the grain boundaries due to the recrystallized α lamellae distribution. The width of the basketweave α lamellae decreases with the increasing microrolling force. The yield strength and ultimate tensile strength of HDMR samples increase with a decrease in elongation anisotropy. This study shows that HDMR can effectively refine grains and improve the tensile properties of titanium alloys, providing a broad prospect for the rapid formation of large titanium alloy parts.

Development of normal blood cells is often suppressed in juvenile myelomonocytic leukemia (JMML), a myeloproliferative neoplasm (MPN) of childhood, causing complications and impacting therapeutic outcomes. However, the mechanism underlying this phenomenon remains uncharacterized. To address this question, we induced the most common mutation identified in JMML (Ptpn11E76K) specifically in the myeloid lineage with hematopoietic stem cells (HSCs) spared. These mice uniformly developed a JMML-like MPN. Importantly, HSCs in the same bone marrow (BM) microenvironment were aberrantly activated and differentiated at the expense of self-renewal. As a result, HSCs lost quiescence and became exhausted. A similar result was observed in wild-type (WT) donor HSCs when co-transplanted with Ptpn11E76K/+BM cells into WT mice. Co-culture testing demonstrated that JMML/MPN cells robustly accelerated differentiation in mouse and human normal hematopoietic stem/progenitor cells. Cytokine profiling revealed that Ptpn11E76K/+MPN cells produced excessive IL-1β, but not IL-6, T NF-α, IFN-γ, IL-1α, or other inflammatory cytokines. Depletion of the IL-1β receptor effectively restored HSC quiescence, normalized their pool size, and rescued them from exhaustion in Ptpn11E76K/+/IL-1R−/−double mutant mice. These findings suggest IL-1β signaling as a potential therapeutic target for preserving normal hematopoietic development in JMML.

Piezoelectric poly(vinylidene fluoride-trifluoroethylene) has demonstrated an ability to promote osteogenesis, and biomaterials with a chirality-patterned topological surface could enhance cellular osteogenic differentiation. In this work, we created a chirality-patterned surface potential distribution of CoFe2O4/poly(vinylidene fluoride-trifluoroethylene (CFO/P(VDF-TrFE)) membranes to explore their osteogenic response under no change in surface chemical and topology, attempting to further strengthen the ability of the membranes to promote osteogenesis. The chirality-patterned surface potential distribution was established by microdomain contact polarization with the help of sinistral/dextral-patterned ITO interdigital microelectrodes. In the in vitroevaluations, the mesenchymal stem cells showed a positive response in osteogenic differentiation to CFO/P(VDF-TrFE) membranes with both sinistral- and dextral-patterned surface potential distributions, however, the dextral-patterned distribution gave a stronger response than the sinistral-patterned one. And the in vivoevaluation showed a response tend in new bone tissue formation similar to the in vitroevaluations. The stronger response in osteogenic differentiation and osteogenesis for the CFO/P(VDF-TrFE) membrane with the dextral-patterned distributions may be attributed to that the intense interaction of the cells with the electrophysiological microenvironment appears due to a correspondingly higher expression of integrin α5β1, which significantly up-regulates the Arp2/3 complex expression, a crucial factor for cytoskeleton reorganization, possibly increases cytoskeleton contractility, and strengthens the transduction of the osteogenesis-related signaling cascade. This work proves that the chirality-patterns in surface potential distributions could provide an osteogenic response similar to a chirality-patterned topological surface.

The scarcity of phosphate ores and increasing water eutrophication are driving economically attractive and environment-friendly approaches for phosphorus recovery. The biomass thermochemical conversion process enables effective protection against water eutrophication caused by phosphorus loss, while allowing the remediation of water eutrophication. This review focuses on the main reaction processes for phosphorus recovery from phosphorus-rich biomass (e.g., sewage sludge and food waste) as secondary phosphorus sources through biomass thermochemical conversion (pyrolysis – pyrochar, hydrothermal – hydrochar, and hydrothermal humification – artificial humic substances). Also, revealing the contribution mechanisms (ligand exchange, electrostatic attraction, and surface precipitation) of phosphate adsorption on metal-modified high-carbon containing lignocellulosic biomass (e.g., crop straw and fruit shells) thermochemical transformation products. This review provides insight on the possibility, superiority, and extensiveness for the prevention and remediation of water eutrophication through biomass thermochemical conversion, and contributes to the further development and application of phosphorus recovery.

The previous virtual screening of ten million compounds yielded two novel nonlipopeptide-like chemotypes as TLR2 agonists. Herein, we present the chemical optimization of our initial hit, 1-phenyl-3-(thiophen-2-yl)urea, which resulted in the identification of SMU-C80 (EC50= 31.02 ± 1.01 nM) as a TLR2-specific agonist with a 370-fold improvement in bioactivity. Mechanistic studies revealed that SMU-C80, through TLR1/2, recruits the adaptor protein MyD88 and triggers the NF-κB pathway to release cytokines such as TNF-α and IL-1β from human, but not murine, cells. To the best of our knowledge, it is the first species-specific TLR1/2 agonist reported until now. Moreover, SMU-C80 increased the percentage of T, B, and NK cells ex vivoand activated the immune cells, which suppressed cancer cell growth in vitro. In summary, we obtained a highly efficient and specific human TLR1/2 agonist that acts through the MyD88 and NF-κB pathway, facilitating cytokine release and the simultaneous activation of immune cells that in turn affects the apoptosis of cancer cells.

The growth of the internet of things (IoT) is creating a demand for convenient energy sources, like organic photovoltaics, to power various small IoT devices. Here, we report a highly crystalline small molecular acceptor (named FCC-Cl) with an optical band gap of 1.71 eV suitable for indoor applications. The important design rationale of FCC-Cl is the combination of a weak electron-donating core and a moderate electron-withdrawing end group, which leads to needed band gap and high crystallinity. The OPVs based on D18:FCC-Cl achieved a high external quantum efficiency up to 85% and a high fill factor of 80% due to the high absorption coefficient and strong crystallinity of FCC-Cl. Consequently, an impressive power conversion efficiency of 28.8% was achieved under a 2,600 K LED lamp at 500 lux. It was also demonstrated that PM6:FCC-Cl-based devices can achieve high efficiencies over a wide range of active-layer thicknesses, which is a feature necessary for large-scale roll-to-roll printing processes.

The topography at the micro/nanoscale level for biomaterial surfaces has been thought to play vital roles in their interactions with cells. However, discovering the interdisciplinary mechanisms underlying how cells respond to micro-nanostructured topography features still remains a challenge. In this work, ∼37 μm 3D printing used titanium microspheres and their further hierarchical micro-nanostructured spheres through hydrothermal treatment were adopted to construct typical model surface topographies to study the preosteoblastic cell responses (adhesion, proliferation, and differentiation). We here demonstrated that not only the hierarchical micro-nanostructured surface topography but also their distribution density played critical role on cell cytocompatibility. The microstructured topography feature surface with middle-density distributed titanium microspheres showed significantly enhanced cell responses, which might be attributed to the better cellular interaction due to the cell aggregates. However, the hierarchical micro-nanostructured topography surface, regardless of the distribution density of titanium microspheres, improved the cell–surface interactions because of the enhanced initial protein adsorption, thereby reducing the cell aggregates and consequently their responses. This work, therefore, provides new insights into the fundamental understanding of cell–material interactions and will have a profound impact on further designing micro-nanostructured topography surfaces to control cell responses.

Rice yields in the black soil region of Northeast China have been declining due to severe soil fertility degradation caused by both biotic and abiotic factors. Artificial humic substance (A-HS) has attracted much attention due to high cost effectiveness and great potential to improve soil fertility. However, the specific effects of A-HS on rice nursery soil nutrient levels remain unclear. This study systematically investigated the effects of rational application of A-HS on soil nutrient turnover and yield, and analyzed the changes in soil nutrients and microbial communities to better understand the application mechanism of A-HS. The results indicated that application of A-HS significantly increased DOM content of the native or seedling soils and improved soil nutrients. In addition, the root growth and yield of the seedlings at maturity were effectively promoted. More interestingly, the application of A-HS significantly altered growth-promoting bacteria, such as Noviherbaspirillum, Klebsiellaand Pedobacter, improving natural barrier formation and soil nutrient conversion. Current results indicate that by altering soil bacterial communities, A-HS significantly enhanced nutrient uptake and accumulation by the crop. In general, this research from multiple aspects demonstrated that the application of A-HS in rice production could be profitable and sustainable. The current study provides valuable insights into the benefits of A-HS in promoting plant growth and development, which could have important implications for agriculture and food security.

Light-induced cell harvest shows much potential in in vitro cell culture. In this work, a light-responsive monolayer graphene (Gr)/titanium dioxide nanodot (TN) film is designed and used for light-induced cell harvest. It is found that after 20 min of 365 nm UV or 450 nm visible light illumination, different types of cells could be detached from the surface effectively. The highest cell detachment ratio reaches about 95%. The mechanism of such a cell detachment is contributed to light illumination generates charge accumulation, which, in turn, changes the conformation of the extracellular matrix protein molecules adsorbed to a more disordered state, and eventually leads to the cells detachment. Such UV and visible light responsive Gr/TiO2film could be a good candidate for a surface with light-induced cell detachment property.

Flavonoids, commonly found in various plants, are a class of polyphenolic compounds having a basic structural unit of 2-phenylchromone. Flavonoid compounds have attracted much attention due to their wide biological applications. In order to facilitate further research on the biomedical application of flavonoids, we surveyed the literature published on the use of flavonoids in medicine during the past decade, documented the commonly found structures in natural flavonoids, and summarized their pharmacological activities as well as associated mechanisms of action against a variety of health disorders including chronic inflammation, cancer, cardiovascular complications and hypoglycemia. In this mini-review, we provide suggestions for further research on the biomedical applications of flavonoids.

The immune response of bone implants is closely related to the interaction between macrophages and biomaterial surfaces. In this work, the polarization behavior of mouse bone marrow-derived macrophages (BMDMs), including their morphology and expression of phenotypic markers, genes and cytokines, on charged surfaces with different potential intensities was systematically explored. We found that the charged surface could effectively promote BMDM polarization, and a higher potential intensity was conducive to the upregulation of the polarization of BMDMs into the M2 phenotype. Based on the analysis of the signaling pathways involved in integrins (αMβ2 and α5β1) and the potassium ion channel (Kv1.3), a possible underlying mechanism revealed that the integrin originated signaling pathways could more dominantly regulate macrophage polarization to the M2 phenotype. The present work therefore demonstrates that the surface charge, as a physicochemical property of material surfaces, could effectively regulate macrophage polarizations, which may provide an immunoregulation view for the surface design of biomaterials.

Urea oxidation is a significant reaction for utilizing urea-rich wastewater or human urine as sustainable power sources which can ease the water eutrophication while generate electricity. A direct urea-hydrogen peroxide fuel cell is a new kind of fuel cell employing urea as fuel and hydrogen peroxide as oxidant which possesses a larger cell voltage. Herein, this work tries to promote the kinetics process of urea oxidation by preparing low-cost and high-efficient NiCo2S4nanowires modified carbon sponge electrode. The carbon sponge used in this work with a similar three-dimensional multi-channel structure to Ni foam, is prepared by carbonizing recycled polyurethane sponge which is also a process of recycling waste. The performance of the prepared catalyst in an alkaline solution is investigated in a three-electrode system. With the introduction of Co element to the catalyst, a reduced initial urea oxidation potential and a high performance are obtained. Furthermore, a direct urea-hydrogen peroxide fuel cell is assembled using the NiCo2S4nanowires modified carbon sponge anode. Results indicate that the prepared catalyst provides a chance to solve the current problems that hinder the development of urea electrooxidation (high initial urea oxidation potential, low performance, and high electrode costs).

The CsI detectors of the High Energy X-ray Telescope of the Hard X-ray Modulation Telescope(HXMT/CsI) can be used for gamma-ray all sky monitoring and searching for the electromagnetic counterpart of gravitational wave source. The instrumental responses are mainly obtained by Monte Carlo simulation with the Geant4 tool and the mass model of both the satellite and all the payloads, which is updated and tested with the Crab pulse emission in various incident directions. Both the Energy-Channel relationship and the energy resolution are calibrated in two working modes (Normal-Gain mode & Low-Gain Mode) with the different detection energy ranges. The simulative spectral analyses show that HXMT/CsI can constrain the spectral parameters much better in the high energy band than that in the low energy band. The joint spectral analyses are performed to ten bright GRBs observed simultaneously with HXMT/CsI and other instruments (Fermi/GBM, Swift/BAT, Konus-Wind), and the results show that the GRB flux given by HXMT/CsI is systematically higher by 7.0±8.8%than those given by the other instruments. The HXMT/CsI-Fermi/GBM joint fittings also show that the high energy spectral parameter can be constrained much better as the HXMT/CsI data are used in the joint fittings.

Recently, the system parameters of Cygnus X-1, i.e., the black hole mass M, the orbital inclination iand the source distance D, have been updated. As the input constraints of the continuum-fitting method, it is necessary to refine the spin with these new parameters. The Hard X-ray Modulation Telescope(HXMT, also named Insight) was successfully launched on June 15th, 2017 in China. In this work, we analyzed spectra obtained by the Insight-HXMT during 2017-2018 and re-estimated the spin via the continuum-fitting method. We first re-estimated the spin using old parameters and found the dimensionless spin parameter to be a⁎>0.934(3σ), which is consistent with previous measurements both from the continuum-fitting and iron-line fitting methods (Gou et al. 2011, Gou et al. 2014; Fabian et al. 2012, Walton et al. 2016, Tomsick et al. 2018). Then, when the new parameters were applied, we obtained an increased spin: a⁎>0.967(3σ), which is also consistent with the recent measurement (Zhao et al. 2020, submitted to ApJ) and also confirms an extreme Kerr black hole lying in this system.

Titanium dioxide (TiO2) photofunctionalization has been demonstrated as an effective surface modification method for the osseointegration of implants. However, the insufficient understanding of the mechanism underlying photofunctionalization limits its clinical applications. Here, we report an ultraviolet (UV) radiant energy-dependent functionalization on TiO2nanodots (TN) surfaces. We found the cell adhesion, proliferation, and osteogenic differentiation gradually increased with the accumulation of UV radiant energy (URE). The optimal functionalizing treatment energy was found to be 2000 mJ/cm2, which could regulate cell-specific behaviors on TN surfaces. The enhanced cell behaviors were regulated by the adsorption and functional site exposure of the extracellular matrix (ECM) proteins, which were the result of the surface physicochemical changes induced by the URE. The correlation between the URE and the reconstruction of surface hydroxyl groups was considered as an alternative mechanism of this energy-dependent functionalization. We also demonstrated the synergistic effects of FAK-RHOA and ERK1/2 signaling pathways on mediating the URE-dependent cell behaviors. Overall, this study provides a novel insight into the mechanisms of photofunctionalization, guiding the design of implants and the clinical practice of photofunctionalization.

Formulating different marketing strategies to apply to various market segments is a noteworthy undertaking for marketing managers. Accordingly, marketing managers should identify sales patterns among different market segments. The study initially applies the concept of recency–frequency–monetary (RFM) scores to segment transaction datasets into several sub-datasets (market segments) and discovers RFM itemsets from these market segments. In addition, three sales features (unique, common, and particular sales patterns) are defined to identify various sales patterns in this study. In particular, a new criterion (contrast support) is also proposed to discover notable sales patterns among different market segments. This study develops an algorithm, called sales pattern mining (SPMING), for discovering RFM itemsets from several RFM-based market segments and then identifying unique, common, and particular sales patterns. The experimental results from two real datasets show that the SPMING algorithm can discover specific sales patterns in various market segments.

It is highly desirable to design and synthesize two-dimensional nanostructured electrode materials with high electrical conductivity, large electrolyte-accessible surface area and more exposed active sites for energy storage applications. Herein, MXene/CoAl-LDH heterostructure has been prepared through electrostatic ordered hetero-assembly of monolayer MXene and edge-rich CoAl-LDH nanosheets in a face-to-face manner on molecular-scale for supercapacitor applications. Benefiting from the unique structure, strong interfacial interaction and synergistic effects between MXene and CoAl-LDH nanosheets, the electrical conductivity and exposed electrolyte-accessible active sites are significantly enhanced. The as-prepared MXene/CoAl-LDH-80% (ML-80) film exhibits high volumetric capacity of 2472 C cm−3in 3 M KOH electrolyte with high rate capability of 70.6% at 20 A g−1. Notably, to the best of our knowledge, the high volumetric capacity is the highest among other previously reported values for supercapacitors in aqueous electrolytes. Furthermore, our asymmetric supercapacitor device fabricated with ML-80 and MXene/graphene composite as cathode and anode, respectively, exhibits impressive volumetric energy density of 85.4 Wh L−1with impressive cycling stability of 94.4% retention ratio after 30,000 continuous charge/discharge cycles.

We present a modified direct demodulation (DD) method for the detection of fast variable objects with the Insight-HXMTGalactic plane survey, which is dedicated to hunting for new transients and monitoring known variable sources. The novelty of the improved DD method is the reconstruction of the modified response matrix, in which the variability of a source is properly handled. Monte Carlo (MC) simulation results demonstrate its power for the detection of variable sources with different time scales, resulting in more accurate location and precise flux monitoring. The application of the method to the Insight-HXMTGalactic plane survey data reveals that the type-II bursts can be well detected for the Rapid Burster MXB 1730–335, with an average rate of 2 bursts min−1in a manner of the well-known relaxation oscillation.

The Galactic plane scanning survey is one of the main scientific objectives of the Hard X-ray Modulation Telescope(known as Insight-HXMT). During the two-year operation of Insight-HXMT, more than 1000 scanning observations have been performed and the whole Galactic plane (0∘

Aqueous rechargeable zinc ion batteries are very attractive in large-scale storage applications, because they have high safety, low cost and good durability. Nonetheless, their advancements are hindered by a dearth of positive host materials (cathode) due to sluggish diffusion of Zn2+in the solid inorganic frameworks. Here, we report a novel organic electrode material of poly 3,4,9,10-perylentetracarboxylic dianhydride (PPTCDA)/graphene aerogel (GA). The 3D interconnected porous architecture synthesized through a simple solvothermal reaction, where the PPTCDA is homogenously embedded in the GA nanosheets. The self-assembly of PPTCDA/GA coin-type cell will not only significantly improve the durability and extend lifetime of the devices, but also reduce the electronic waste and economic cost. The self-assembled structure does not require the auxiliary electrode and conductive agent to prepare the electrode material, which is a simple method for preparing the coin-type cell and a foundation for the next large-scale production. The PPTCDA/GA delivers a high capacity of ≥200 mAh g–1with the voltage of 0.0∼1.5 V. After 300 cycles, the capacity retention rate still close to 100%. The discussion on the mechanism of Zn2+intercalation/deintercalation in the PPTCDA/GA electrode is explored by Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterizations. The morphology and structure of PPTCDA/GA are examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

Viscosity-temperature characteristics of high borosilicate glass were investigated in detail by means of rotor viscometer and dilatometer. The neck-down deformation process of glass tube was simulated by Polyflow software, and the simulation was verified by the secondary drawing of glass perform. The results showed that the high temperature viscosity of borosilicate glass is higher compared to that of ordinary optical glass. In the high temperature stage, the fitting curves of VFT, AV, AG and MYEGA models are all in good agreement with the tested curve. However, in the low temperature stage, only viscosity fitted by VFT model is close to the tested value. Based on Navier-Stokes equation, a mathematical model of neck-down deformation of glass tube during secondary drawing is established. It is found that viscosity is the key material intrinsic factor affecting neck-down process of glass tube. The distribution of inner and outer diameters of glass tube along the drawing direction is simulated and analyzed under different feeding and drawing rates. The deviation between the steady-state dimension simulated and that actually drawn is only ±0.06 mm.

Surface-mediated gene delivery has attracted more and more attentions in biomedical research and applications because of its characteristics of low toxicity and localized delivery. Herein, a novel visible-light-regulated, surface-mediated gene-delivery platform is exhibited, arising from the photoinduced surface-charge accumulation on silicon. Silicon with a pn junction is used and tested subsequently for the behavior of surface-mediated gene delivery under visible-light illumination. It is found that positive-charge accumulation under light illumination changes the surface potential and then facilitates the delivery of gene-loaded carriers. As a result, the gene-expression efficiency shows a significant improvement from 6% to 28% under a 10 min visible-light illumination. Such improvement is ascribed to the increase in surface potential caused by light illumination, which promotes both the release of gene-loaded carriers and the cellular uptake. This work suggests that silicon with photovoltaic effect could offer a new strategy for surface-mediated, gene-delivery-related biomedical research and applications.

The cross-linked porous Ti3C2Tx-RGOfilm was designed and synthesized by the micro-explosion reaction. Such a flexible and freestanding Ti3C2Tx-RGO electrode presented an ultrahigh capacitance and remarkable rate performance, which is less effect by mass loading.

Mesenchymal stem cells (MSCs), which are undifferentiated stem cells with the property of stemness and the potential to differentiate into multiple lineages, including osteoblasts, have attracted a great deal of attention in bone tissue engineering. Consistent with the heterogeneity of MSCs, various surface markers have been used. However, it is still unclear which markers of MSCs are best for cell amplification in vitro and later bone regeneration in vivo. Krüppel‐like Factor 2 (KLF2) is an important indicator of the stemness of human MSCs (hMSCs) and as early vascularization is also critical for bone regeneration, we used KLF2 as a novel in vitro marker for MSCs and investigated the angiogenesis and osteogenesis between KLF2+MSCs and endothelial cells (ECs). We found a synergistic interaction between hMSCs and human umbilical vein ECs (HUVECs) in that KLF2+stemness‐maintained hMSCs initially promoted the angiogenesis of HUVECs, which in turn more efficiently stimulated the osteogenesis of hMSCs. In fact, KLF2+hMSCs secreted angiogenic factors initially, with some of the cells then differentiating into pericytes through the PDGF‐BB/PDGFR‐β signaling pathway, which improved blood vessel formation. The matured HUVECs in turn synergistically enhanced the osteogenesis of KLF2+hMSCs through upregulated vascular endothelial growth factor. A three‐dimensional coculture model using cell‐laden gelatin methacrylate (GelMA) hydrogel further confirmed these results. This study provides insight into the stemness‐directed synergistic interaction between hMSCs and HUVECs, and our results will have a profound impact on further strategies involving the application of KLF2+hMSC/HUVEC‐laden GelMA hydrogel in vascular network bioengineering and bone regeneration. Mechanism of interactions between KLF2+ stemness‐maintained human mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs). The signaling regulation pathway by which KLF2+ stemness‐maintained hMSCs initially promoted angiogenesis of HUVECs and eventually efficiently induced osteogenesis.

We make the in-orbit calibration to the point-spread functions (PSFs) of the collimators of the Hard X-ray Modulation Telescopewith the scanning observation of the Crab. We construct the empirical adjustments to the theoretically calculated geometrical PSFs. The adjustments contain two parts: a rotating matrix to adjust the directional deviation of the collimators and a paraboloidal function to correct the inhomogeneity of the real PSFs. The parameters of the adjusting matrices and paraboloidal functions are determined by fitting the scanning data with lower scanning speed and smaller intervals during the calibration observations. After the PSF calibration, the systematic errors in source localization in the Galactic plane scanning survey are 0∘.010, 0∘.015, 0∘.113for the Low-Energy Telescope (LE), the Medium-Energy telescope (ME) and the High-Energy telescope (HE), respectively; meanwhile, the systematic errors in source flux estimation are 1.8%, 1.6%, 2.7% for LE, ME and HE, respectively.

Metal–organic framework (MOF)-derived composites of transition metal oxides and porous carbon show great potential for energy storage applications. Selenylation is an effective strategy to improve the electrochemical properties of electrode materials. A facile one-step derivation and selenylation of MOFs is proposed here to obtain CoSe2nanoparticles embedded into an N-doped carbon skeleton material (CoSe2/NC). Moreover, the composite is directly grown on nickel foam as nanosheet arrays, rather than on other materials as powders. The CoSe2/NC electrode with special construction exhibits a high capacity of 120.2 mA h g–1at 1 A g–1and an excellent cyclic ability of 8% loss after 10,000 cycles. An asymmetric supercapacitor CoSe2/NC-NF//AC displays a maximum energy density of 40.9 W h kg–1at 980 W kg–1. Moreover, the device has demonstrated that it can successfully charge a mobile phone. The outstanding performance indicates promising potential of CoSe2/NC-NF electrodes for supercapacitors.

Gene delivery based on bioactive coatings on collagen has great potential for applications in bone repair. Meanwhile, controlled gene delivery at specific times/regions is essential for an efficient and complete bone reconstruction process. However, spatio-temporal regulation of gene release and delivery remains a great challenge. In this paper, we used visible light illumination to effectively regulate gene release and subsequent delivery into biological cells. A visible light responsive and bioactive nanocomposite coating (based on collagen/gold nanoparticles, e.g., Col/AuNPs) was prepared through hydrothermal and sol–gel processes and was used as a loading platform for complexes of enhanced green fluorescent protein and Lipofectamine2000 (LF/GFP). The results showed that the amount of immobilized LF/GFP was increased on Col/AuNPs and the release of pre-adsorbed LF/GFP was significantly enhanced in a spatio-temporal and controlled manner under visible light illumination. Moreover, the cellular intake of the released genes was improved, thus enhancing the gene expression efficiency of the cells. The mechanism of enhanced controlled gene delivery was attributed to the changes in collagen structures and rearrangement of cytoskeletal structures induced by the photothermal effect. The developed Col/AuNP composite coating is effective for both controlled surface-mediated gene delivery and gene-mediated bone repair.

Metallic anodes have high theoretical specific capacities and low electrochemical potentials. However, short-circuit problems caused by dendritic deposition and low Coulombic efficiency limit the cyclic life and safety of metallic anode-based batteries. Herein, dendrite-free and flexible three-dimensional (3D) alkali anodes (Li/Na-Ti3C2Tx-rGO) are constructed by infusing molten lithium (Li) or sodium (Na) metal into 3D porous MXene Ti3C2Tx-reduced graphene oxide (Ti3C2Tx-rGO) membranes. First-principles calculations indicate that large fractions of functional groups on the Ti3C2Txsurface lead to the good affinity between the Ti3C2Tx-rGO membrane and molten alkali metal (Li/Na), and the formation of Ti-Li/Na, O-Li/Na, and F-Li/Na mixed covalent/ionic bonds is extremely critical for uniform electrochemical deposition. Furthermore, the porous structure in Li/Na-Ti3C2Tx-rGO composites results in an effective encapsulation, preventing dendritic growth and exhibiting stable stripping/plating behaviors up to 12 mA·cm–2and a deeper capacity of 10 mA·h·cm–2. Stable cycling performances over 300 h (750 cycles) at 5.0 mA·cm–2for Li-Ti3C2Tx-rGO and 500 h (750 cycles) at 3.0 mA·cm–2for Na-Ti3C2Tx-GO are achieved. In a full cell with LiFePO4cathodes, Li-Ti3C2Tx-rGO electrodes show low polarization and retain 96.6% capacity after 1000 cycles. These findings are based on 2D MXene materials, and the resulting 3D host provides a practical approach for achieving stable and safe alkali metal anodes.

Mechanical stimulus has been demonstrated to be critical to stem cell fate commitment and tissue repair. However, it still remains a challenge to remote control of the mechanical stimulus acting on cells. Here, we designed a magnetic Fe3O4/mineralized collagen coating on titanium substrate to regulate the osteogenic differentiation of mesenchymal stem cells (MSCs). The mode and intensity of the mechanical stimulus acting on cells could be controlled by adjusting the remote applied magnetic field. We demonstrated that the adhesion, proliferation, and differentiation of MSCs were strongly dependent on the mode and intensity of the mechanical stimuli. Strikingly, the periodic mechanical stimulus (12 h every other day, PMS) showed the significantly up-regulated expression of osteogenesis-related markers, ALP, compared to that of the static mechanical stimulus mode. The reason is proposed as (1) initially, PMS mode enables the coatings to have appropriate surface mechanical properties for promoting focal adhesion, integrin expression, and cytoskeleton development of MSCs, letting MSCs have good capability of accepting as well as transferring mechanical stimuli; (2) during MSCs growth, PMS mode may effectively manipulate MSCs cytoskeleton development and movement, and mechanotranduction mechanism could be well activated; thus, MSCs osteogenic differentiation is enhanced. This work therefore provides a novel strategy to engineer bioactive coatings with remote control over the intensity and mode of the mechanical stimulus acting on cells, and would have an impact on the design of smart biomaterial surfaces for orthopedic applications.

Graphene (Gr) presents promising applications in regulating the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). Light illumination is regarded as a spatiotemporally controllable, easily applicable, and noninvasive mean to modulate material responses. Herein, Gr-transferred silicon (Gr/Si) with a Schottky junction is utilized to evaluate the visible-light-promoted osteogenic differentiation of BMSCs. Under light illumination, light-induced charges, owing to the formation of the Schottky junction at the interface of Gr and Si, accumulated on the surface and then changed the surface potential of Gr/Si. The Schottky junction and surface potential at the interface of Gr and Si was measured by photovoltaic test and scanning Kelvin probe microscopy. Alkaline phosphatase (ALP) activity and quantitative real-time polymerase chain reaction (PCR) measurement showed that such variations of surface improved the osteogenic differentiation of BMSCs, and the activation of the voltage-gated calcium channels through surface potential and accumulation of cytosolic Ca2+could be the reason. Moreover, X-ray photoelectron spectroscopy characterization showed that surface charge could also affect BMSCs differentiation through the promotion or inhibition of the adsorption of osteogenic growth factors. Such light-promoted osteogenic differentiation of BMSCs on Gr/Si may have huge potential for biomedical materials or devices for bone regeneration application.

Purpose: As researchers are writing a draft paper with incomplete structure or text, one of burdensome tasks is to deliberate about which references should be cited for one sentence or paragraph of this draft. In view of the rapid increase in the number of research papers, researchers desire to figure out a better way to do citation recommendations in developing their draft papers. The purpose of this paper is to propose citation recommendation algorithms that enable the acquisition of relevant citations for research papers that are still at the drafting stage. This study attempts to help researchers to select appropriate references among the vast amount of available papers and make draft papers complete in reference citation. Design/methodology/approach: This study adopts a model for recommending citations for incomplete drafts. Four algorithms are proposed in this study. The first and second algorithms are unsupervised models, applying term frequency-inverse document frequency and WordNet technologies, respectively. The third and fourth algorithms are based on the second algorithm to integrate different weight adjustment strategies to improve performance. Findings: The proposed recommendation method adopts three techniques, including using WordNet to transform vector and setting adjustment weights according to structural factors and the information completeness degree, to generate citation recommendation for incomplete drafts. The experiments show that all these three techniques can significantly improve the recommendation accuracy. Originality/value: None of the methods employed in previous studies can recommend articles as references for incomplete drafts. This paper addresses the situation that a draft paper can be incomplete either in structure or text or both. Recommended references, however, can be still generated and inserted into any desired sentence of the draft paper.

A facile strategy is needed for accurate time–space supply of suitable growth factors or drugs. Polypyrrole (PPy) was able to carry almost all kinds of negatively charged biomolecules through anodizing method, which made it an appropriate way for codeposition of multiple molecules. The difference in the conjugation between different molecules and PPy makes it possible for selective release when the redox state of PPy changes. In this work, bovine serum albumin (BSA) and heparin (Hep) were chosen to be the model molecules in view of their differences in the level of electronegativity and molecular weight. Double-layer deposition method was used to improve the biocompatibility of PPy/BSA/Hep film. It was found the content of BSA and Hep in the film can be controlled by regulating deposition current and time. BSA release was facilitated under positive voltage and then promote the proliferation of preosteoblasts, while Hep release was promoted under negative voltage and enhance cell differentiation. Our work provides a dual-molecule model in PPy for selective release and further explores the mechanism of release selectivity, this discovery has potential applications in tissue engineering and regenerative medicine.

Cell responses to oxide biomaterials depend on the protein adsorption behavior of the biomaterial surface. Thus, the inherent properties of oxide biomaterial surfaces play a key role in this process. However, commonly used biomaterials, such as calcium phosphate and titanium dioxide, have surfaces with strong mineralization, which may interfere with the ability to clarify the key aspects of the oxide biomaterial regarding protein adsorption and cellular processes. Here, nonmineralized crystalline and vitreous silica were selected as model oxide biomaterials to explore the inherent properties of these materials on the absorption behavior of the functional protein fibronectin (Fn) and on the osteogenic differentiation of mesenchymal stem cells (MSCs). We demonstrated that due to the smaller O1sbinding energy, the weaker polarization of oxygen atoms in vitreous silica produced a greater amount of acidic hydroxyls after hydration compared to crystalline silica. These distinct features significantly upregulated the exposure of arginylglycylaspartic acid (RGD) and synergy sites (PHSRN) of Fn and eventually enhanced the osteogenic differentiation of MSCs on vitreous silica surfaces through activation of the integrin-linked kinase (ILK) signaling pathway. Our results highlight the key role of inherent oxide biomaterial crystallinity in protein adsorption and cell behavior.

Divalent main-group-elemental ions are widely used to improve osteogenic capacity of implants biofabricated from Ti and its alloys. However, the conclusions regarding their osseointegration and immunogenicity are always inconsistent because of the multiple bone remodeling processes as well as the distinct material surface features arising from processing. Here we successfully manufactured the porous micro/nanostructured surface topography with divalent main-group-elemental ions (Mg2+, Ca2+, Sr2+, Ba2+) on substrates through hydrothermal treatment and comprehensively evaluated the complex bone remodeling processes, including osseointegration, immunogenicity, and fibrosis of substrates and implants. We found that Sr-modified implants not only upregulated the adhesion and proliferation of mesenchymal stem cells but also the differentiation of osteogenic markers compared with those modified by other divalent main-group-elemental ions (Mg2+, Ca2+, Ba2+). More importantly, the osteoclastogenesis, immunogenicity, and fibrosis of Sr-modified implants were also significantly downregulated. In vivo, evaluations of new bone formation and histological morphology at the interface of implant and host as well as the removal torque similarly indicated the improved osseointegration of Sr-modified implants as well as the absence of immunogenicity, fibrosis, or necrosis. Our results suggested that among various divalent main-group-elemental ions, Sr2+might be a promising one for enhancing bone remodeling, which can be used to instruct functionalization of the surfaces of biofabricated Ti-based orthopedic and dental implants in the future.

The exploration and growth of novel cost-effective top cell materials is one of the great hot topics for the development of Si-based tandem solar cells. ZnSiP2was thought to be a promising candidate of the top cell material for the Si tandem solar cell. In this work, ZnSiP2single crystal film with the stoichiometric ratio was successfully grown on a Si substrate by the liquid phase epitaxy method for the first time. The surface morphology, thickness, composition, and the orientation of the film were characterized by SEM, EDS, EPMA, and the high-resolution XRD. The results show that a continuous epitaxial ZnSiP2film with the thickness of 3 μm was grown on the Si substrate. In addition to this continuous film, many island single crystals were also observed on the surface of the film. The high-resolution XRD φ scan results indicated that the film as well as these isolated islands crystallized with the same orientation, c-orientation with respect to the (100) Si substrate, without any misoriented domains. The microstructure of the ZnSiP2/Si interface characterized by the high-resolution transmission electron microscopy image, as well as the selected area electron diffraction patterns of the ZnSiP2thin films and Si substrates, also confirmed the epitaxial growth of ZnSiP2on the Si substrate. The electrical conductivity σ, Hall mobility μH, and carrier concentrations nof the ZnSiP2film were 1.38 × 10–5Ω–1cm–1, 94.5 cm–2V–1s–1, and 9.11 × 109cm–3, respectively. Our work paves the way for the development of ZnSiP2silicon-based tandem solar cell devices.