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As a promising ultra-wide bandgap semiconductor material, gallium oxide (Ga2O3) is attracting an extensive attention of researchers due to its feasible growth process, appropriate bandgap of 4.4-5.3 eV allowing for deep-ultraviolet (deep-UV) detection, good physical and chemical stability, high breakdown field strength and electron mobility, etc. Different from the strict processes for controllable crystalline Ga2O3 (usually refer to stable monoclinic β-Ga2O3), amorphous Ga2O3 (a-Ga2O3) film can be prepared uniformly at low temperature on a large-area deposition substrate, suggesting great advantages such as low manufacturing cost and excellent flexibility, dispensing with high-temperature and high vacuum techniques. Thus, a-Ga2O3 extremely facilitates important applications in various applied fields. Therefore, in this concise review, we summarized several major deposition methods for a-Ga2O3 films, of which the characteristics were discussed. Additionally, potential methods to optimize the film properties were proposed by right of the inspiration from some recent studies. Subsequently, the applications of a-Ga2O3 thin films, e.g., in photodetectors, resistive random access memories (RRAMs) and gas sensors, were represented with a fruitful discussion of their structures and operating mechanisms.

As a 2D material, MXene has emerged as an excellent electrode material for optoelectronic devices due to its high conductivity and hydrophilic surface. Here, the Ti3C2-based MXene was employed to construct the Ti3C2/-Ga2O3 Schottky junction photodetector. The fabricated device demonstrated a self-powered operation manner with an extremely low dark current (0.07 pA), an outstanding light on/off switch ratio (2.5106), a remarkable photo-response speed (43 ms/145 ms), a responsivity (R) of 15.5 mA/W, an external quantum efficiency (EQE) of 7.5% and a detectivity (D*) of 2.151011 Jones. Such excellent photodetection performance that is comparable or even higher than those of Ga2O3 Schottky photodetectors previously reported are originated from the excellent conductivity of MXene, good crystallization of -Ga2O3, and their well-matched energy level. Additionally, our Schottky junction device is capable of sensing solar-blind UV region and exhibits excellent stability in the air environment. The perfect combination of 2D MXene and wide-bandgap -Ga2O3 proposes a novel route for the self-powered Schottky devices.

Solar blind ultraviolet (SBUV) self-powered photodetectors (PDs) have a great number of applications in civil and military exploration. Ga2O3 is a prospective candidate for SBUV detection owing to its reasonable bandgap corresponding to the SBUV waveband. Nevertheless, the previously reported Ga2O3 photovoltaic devices had low photoresponse performance and were still far from the demands of practical application. Herein, we propose an idea of using spiro-MeOTAD (spiro) as the SBUV transparent conductive layer to construct p-i-n PDs (p-spiro/Ga2O3/n-Si). With the aid of double built-in electric fields, the designed p-i-n PDs could operate without any external power source. Furtherly, the influence of spiro thickness on improving the photoelectric performance of devices is investigated in detail and the optimum device is achieved, translating to a peak responsivity of 192 mA/W upon a weak 254 nm light illumination of 2 μW/cm2 at zero bias. In addition, the I-t curve of our PD shows binary response characteristics and a four-stage current response behavior under a small forward bias, and also, its underlying working mechanism is analyzed. In sum, this newly developed device presents great potential for booming the high energy-efficient optoelectronic devices in the short run.

In this work, a Si-doped $\beta $ -Ga2O3 trench Schottky photodiode has been designed and fabricated. This photodiode works as a dual-mode solar-blind ultraviolet sensor with a photo-to-dark current ratio (PDCR) of $3.93\times 10 ^{5}$ , a responsivity (R) of 152.63 A/W, an external quantum efficiency (EQE) of 74653%, rise and decay time of 0.06 s and 0.06 s, under the irradiation of 254 nm ultraviolet light with intensity of $200~\mu \text{W}\cdot $ cm−2. Moreover, it has the potential to be a self-powered photodetector at zero bias. In general, this trench Schottky contact design has a good developing prospect in the field of ultraviolet solar-blind detection with high performances.

A novel p–i–n self-powered solar-blind UV photodetector based on p-type spiro-MeOTAD (spiro), Ga2O3, and n-type Si is fabricated. The p-type spiro film is spin-coated on the surface of the Ga2O3 film deposited on a Si wafer via a metal–organic chemical vapor deposition (MOCVD) system. Benefitting from the superior carrier-separation ability of the double built-in electric fields, the effective carrier transport of the novel vertical structure and the high solar-blind UV transmittance of the spiro film, the self-powered responsivity of the p–i–n-type photodetector based on spiro/Ga2O3/Si increases to 4.43 mA W−1 under UV light (λ = 254 nm), which is ∼54-fold that of the Ga2O3/Si photodetector (0.22 mA W−1). Meanwhile, the response speed (0.03/0.196 s) of the p–i–n device is also dramatically improved by introducing the spiro layer. The reported achievements of our work provide a new way to construct a high-sensitivity self-powered UV photodetector for photovoltaic and optoelectronic applications.

In this retrospective study we assessed the efficacy and safety of tocilizumab in patients with critical or severe coronavirus disease 2019 (COVID-19). We enrolled 181 patients admitted to Huoshenshan Hospital (Wuhan, China) with confirmed COVID-19 between January 2020 and February 2020. Ninety-two patients were treated with tocilizumab, and 89 patients were treated conventionally. We analyzed the clinical manifestations, changes in CT scan images, and laboratory tests before and after tocilizumab treatment, and compared these results with the conventionally treated group. A significant reduction in the level of C-reactive protein was observed 1 week after tocilizumab administration. In some cases this meant the end of the IL-6-related cytokine storm. In addition, tocilizumab relieved fever, cough, and shortness of breath with no reported adverse drug reactions. These findings suggest tocilizumab improves clinical outcomes and is effective for treatment of patients with critical or severe COVID-19. However, future clinical trials are needed to better understand the impact of tocilizumab interference with IL-6 and provide a therapeutic strategy for treatment of COVID-19.

Background: Chronic whiplash-associated disorder (WAD) can develop after flexion/extension injuries and may be refractory to standard-of-care therapies. Aim: To present successful treatment of severe, longstanding, treatment resistant WAD with prolotherapy. Materials & methods: Four, monthly sessions of fluoroscopically guided prolotherapy with phenol-glycerin-glucose. Electronic data on pain (visual analog score), disability (Oswestry Disability Index), pain interference, depression, anxiety, sleep and quality of life were collected with University of Washington’s (WA, USA) online tool for a total of 21 months. This study conforms to the Case Report Guidelines (CARE). Results: Significant improvement was achieved and maintained through 18 months after treatment in all assessed pain and functional measures. Conclusion: Regenerative medicine, including prolotherapy may be an appropriate treatment option for carefully selected patients with WAD.

Hierarchical hollow structures show particular properties and promising applications, and therefore have been attracting attention. To the best of our knowledge, ZnO/C hollow sphere constructed by octahedron has not been reported so far. In this paper, a solvothermal process has been developed to prepare precursor hollow spheres constructed by octahedron. The precursor can be converted to hollow ZnO/C spheres with well-preserved morphology via thermal decomposing. In order to research the formation mechanism, intermediate precursors were acquired at different reaction times, and a possible growth mechanism was also proposed. When the hierarchical ZnO/C hollow spheres constructed by octahedron were used as the adsorbents, the Langmuir model can well describe the adsorption isotherms. For Congo red and Pb(II), the maximum adsorption capacities are up to 392 and 314 mg g−1, respectively. Furthermore, the as-prepared ZnO/C displays good recyclability in the removal of Congo red. Our results provide new strategy for the synthesis of novel ZnO/C hollow sphere, which has promising adsorption ability for water treatment.

Developing scalable and robust processing methods with low material waste remains a challenge for organic solar cells (OSCs) to become a practical renewable energy source. Here, we present a novel low-cost processing approach termed as soft porous blade printing (SPBP), which uses a layer of soft porous material such as filter paper as the printing blade. The inherent porous microstructure of the blade offers high shear rates that facilitate the alignment, crystallization, and orientation of active materials during printing. Moreover, by eliminating the suspended liquid meniscus, SPBP relaxes the stringent requirement of gap control and enables continuous ink delivery for uninterrupted film fabrication with adjustable thickness. Higher photovoltaic performances are achieved in the SPBP-printed OSCs than those of the spin-coated counterparts for two nonfullerene-acceptor active-layer systems (Y6:PM6 and PTQ10:IDIC). Y6:PM6 cells printed by SPBP without any additive exhibit power conversion efficiencies up to 14.75%, which is among the highest reported to date for non-spin-coated OSCs.

A self-powered solar-blind ultraviolet (UV) photodetector (PD) was successfully constructed on a Ga2O3/Bi2WO6 heterojunction, which was fabricated by spin-coating the hydrothermally grown Bi2WO6 onto MOCVD-grown Ga2O3 film. The results show that a typical type-I heterojunction is formed at the interface of the Ga2O3 film and clustered Bi2WO6, which demonstrates a distinct photovoltaic effect with an open-circuit voltage of 0.18 V under the irradiation of 254 nm UV light. Moreover, the Ga2O3/Bi2WO6 PD displays excellent photodetection performance with an ultra-low dark current of ∼ 6 fA, and a high light-to-dark current ratio (PDCR) of 3.5 × 104 in self-powered mode (0 V), as well as a best responsivity result of 2.21 mA/W in power supply mode (5 V). Furthermore, the PD possesses a stable and fast response speed under different light intensities and voltages. At zero voltage, the PD exhibits a fast rise time of 132 ms and 162 ms, as well as a quick decay time of 69 ms and 522 ms, respectively. In general, the newly attempted Ga2O3/Bi2WO6 heterojunction may become a potential candidate for the realization of self-powered and high-performance UV photodetectors.

Secondary hematite (SH) is a serious factor resulting in reduction degradation of iron ore sinter in a blast furnace; however, until now, a quantitative study for SH formation had not been reported. In this work, the effects of gangue composition, including MgO, Al2O3 and SiO2, on the solid-state formation in the sintering process of iron ore fines were investigated quantitatively. It shows that the SH formation decreased from 67.84% to 46.11%, 35.44% and 22.37% after adding 1.0%, 3.0% and 5.0% MgO, respectively, while for Al2O3, the amount increased to 69.38%, 69.98% and 70.56%, respectively. For SiO2, the amount changed to 68.14%, 61.59% and 47.96%, respectively. Simultaneously, the magnetite (magnesioferrite) formation increased from 8.24% to 34.79%, 50.26% and 70.45% after adding 1.0%, 3.0% and 5.0% MgO, respectively. For Al2O3 and SiO2, the amount changed to 8.95%, 8.37%, 7.62% and 7.62%, 11.10%, 18.77%, respectively, compared with no gangue. This indicates that the SH formation increased with decrease in magnesioferrite. It was found that the decrease in SH formation relates to the diffusion of Mg2+ in magnesioferrite, which inhibits the solid-state formation of SH kinetically. A supposition was suggested that a maghemite existed at a high temperature, and decreased with an increase in MgO addition. This would be another reason to improve the degradation performance of iron ore sinter.

A flower-like SnO2–SnO/porous GaN (FSS/PGaN) heterojunction was fabricated for the first time via a facile spraying process, and the whole process also involved hydrothermal preparation of FSS and electrochemical wet etching of GaN, and SnO2–SnO composites with p–n junctions were loaded onto PGaN surface directly applied to H2S sensor. Meanwhile, the excellent transport capability of heterojunction between FSS and PGaN facilitates electron transfer, that is, a response time as short as 65 s and a release time up to 27 s can be achieved merely at 150 °C under 50 ppm H2S concentration, which has laid a reasonable theoretical and experimental foundation for the subsequent PGaN-based heterojunction gas sensor. The lowering working temperature and high sensitivity (23.5 at 200 ppm H2S) are attributed to the structure of PGaN itself and the heterojunction between SnO2–SnO and PGaN. In addition, the as-obtained sensor showed ultra-high test stability. The simple design strategy of FSS/PGaN-based H2S sensor highlights its potential in various applications.

In this work, anatase structure TiO2 particles with a preferential grain growth direction of [002] were synthesized by a facile and modified sol–gel approach. The pellets pressed from the TiO2 particles possess colossal dielectric constant (> 7 × 103 at 100 Hz and room temperature). The colossal dielectric constant behavior can be associated with the Maxwell–Wagner relaxation due to the textured grain structure. This approach is simple and provides an avenue to obtain the excellent dielectric properties of ceramics with oriented grains. Contrary to traditional relaxation behavior, an anomalous dielectric behavior was observed above room temperature. This abnormal dielectric behavior was caused by the positive temperature coefficient of resistance effect resulting from humidity response.

IntroductionPeriodontal disease and osteoporosis are common chronic diseases, especially for the postmenopausal women. Several original studies explore the association, but there still controversial. Therefore, we will conduct this systematic review and meta-analysis to assess the association between periodontal disease and osteoporosis in postmenopausal women.Methods and analysisThis study adheres to the Preferred Reporting Items for Systematic Reviews and Meta-analyses for Protocols. We will systematically search Medline/PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science and Scopus from inception to August 2021 to collect all relevant publications, with no restrictions on publication date or languages. Study selection, data extraction and risk of bias assessment will be conducted independently by two trained reviewers independently. The Cochrane’s tool for assessing risk of bias, Newcastle-Ottawa Scale and Agency for Healthcare Research and Quality will be used for the risk of bias assessment. OR, HR and risk ratio with 95% CI were considered as the effect size for dichotomous outcomes, weighted mean difference with 95% CI were calculated as the effect size for continuous outcomes. Random-effects models will be used. Heterogeneity between studies will be assessed via the forest plot and I². Publication bias will detected by funnel plots, Begg’s test and Egger’s test. The subgroup analyses and sensitivity ananlyses will also be used to explore and interpret the heterogeneity.Ethics and disseminationThis study does not require ethical approval. We will disseminate our findings by publishing results in a peer-reviewed journal.PROSPERO registration numberCRD42021225746.

A 4×4 beta-phase gallium oxide (β-Ga2O3) deep-ultraviolet (DUV) rectangular 10-fingers interdigital metal-semiconductor-metal (MSM) photodetector array of high photo responsivity is introduced. The Ga2O3 thin film is prepared through the metalorganic chemical vapor deposition technique, then used to construct the photodetector array via photolithography, lift-off, and ion beam sputtering methods. The one photodetector cell shows dark current of 1.94 pA, photo-to-dark current ratio of 6×107, photo responsivity of 634.15 A⋅W−1, specific detectivity of 5.93×1011 cm⋅Hz1/2⋅W−1 (Jones), external quantum efficiency of 310000%, and linear dynamic region of 108.94 dB, indicating high performances for DUV photo detection. Furthermore, the 16-cell photodetector array displays uniform performances with decent deviation of 19.6% for photo responsivity.

Objective. To investigate and study the related risk factors of gastric cancer (GC) patients, to establish a high-risk scoring model of GC by multiple logistic regression analysis, and to explore the establishment of a GC screening mode with clinical opportunistic screening as the main method, and by using the pattern of opportunistic screening to establish the screening of high-risk GC patients and the choice of screening methods in the clinical outpatient work. Methods. Collected the epidemiological questionnaire of 99 GC cases and 284 non-GC patients (other chronic gastric diseases and normal) diagnosed by the General Hospital of Ningxia Medical University from October 2017 to March 2019. Serum pepsinogen (PG) levels were measured by enzyme-linked immunosorbent assay (ELISA) and confirmed Helicobacter pylori (Hp) infection in gastric mucosa tissues by Giemsa staining. Determined the high-risk factors and established a scoring model through unconditional logistic regression model analysis, and the ROC curve determined the cut-off value. Then, we followed up 26 patients of nongastric cancer patients constituted a validation group, which validated the model. Results. The high-risk factors of GC included age≥55, male, drinking cellar or well water, family history of GC, Hp infection, PGI≤43.6 μg/L, and PGI/PGII≤2.1. Established the high-risk model: Y=A×age+30×gender+30×drinking water+30×Hp infection+50×family history of GC+B×PG level. The ROC curve determined that the cut-off value for high-risk GC population was ≥155, and the area under the curve (AUC) was 0.875, the sensitivity and specificity were 87.9% and 71.5%. Conclusions. According to the risk factors of GC, using statistical methods can establish a high-risk scoring model of GC, and the score≥155 is divided into the screening cut-off value for high-risk GC population. Using this model for clinical outpatient GC screening is cost-effective and has high sensitivity and specificity.

A facile method, by sintering commercially available TiO2 in inert gas at high temperature, was used to obtain Ti3+ self-doping blue rutile TiO2 ceramic powder. Our results indicate that Ti3+ ions exist in bulk of TiO2 and the reduced TiO2 exhibits enhanced visible-light absorption. The reduced TiO2 possesses superior photocatalytic ability in photodegradation of methylene blue under Xe light illumination. Moreover, the reduced TiO2 exhibits good stability even after 12 months. This method provides an economical and universally applicable way to synthesize commercially available TiO2 powder with high and stable photocatalytic performance, which may have the promise for solar applications.

Nanomaterials with hollow structures have been the focus of attention in recent years because of their widespread applications. In this article, we successfully developed an effective method to synthesize polyhedral CoS2 hollow nanostructure using ZIF-67 as the sacrificial template. When assessed as the adsorbents for fluorescein sodium and Pb(II) removal, the adsorption isotherm show a good fit with the Langmuir model, with the maximum adsorption capacities of 289 and 758 mg g−1, respectively. In addition, the as-prepared CoS2 also has a good recycling ability in the removal of fluorescein sodium dye, and the adsorption efficiency remains 98% after the four cycles. The superior performance for adsorption of dye and heavy metal ion make the polyhedral CoS2 hollow nanostructure have potential applications in water treatment.

Compared with pure MOFs, core-shell heterostructures of noble-metal@MOFs have attracted tremendous interest due to their unique structure and extensive applications. In the present study, we have successfully synthesized well-defined core-shell Ag@ZIF-8 nanowires. The products growth process has been investigated by examining the products obtained at different intervals and the thickness of ZIF-8 shell ranging from 30 to 100 nm can be technically obtained by tuning the quantity of Ag nanowires. Ag@ZIF-8 has been proven to possess large specific surfaces and high thermal stability. Additionally, the antibacterial activity of Ag@ZIF-8 is further tested against Bacillus subtilis and Escherichia coli BL21. The results reveal that Ag@ZIF-8 core-shell heterostructure nanowires have effective activities against the two types of bacterial strains.

In this work, a solar-blind ultraviolet (UV) photodetector based on a three-terminal enhancement-mode (E-mode) Si-doped β-Ga2O3 (β-Ga2O3:Si) metal-semiconductor field-effect transistor structure is demonstrated, whose threshold voltage (V th) and subthreshold swing are 4.04 V and 1.4 V dec−1, respectively. A 400 nm thick β-Ga2O3:Si thin film is prepared on sapphire substrate by using metal-organic chemical vapor deposition method. Controlling the channel currents by the Schottky gate voltage in the dark and under illuminations, the photodetector shows dark current (I dark) as low as 13.4 pA, photo-to-dark current ratio of 4.85 × 104 and linear dynamic range of 29.6 dB, illuminated by 254 nm UV light of 245 μW cm−2. As the UV light is turned on and off, the output current rise and decay time (τ r and τ d) are 420 ms and 350 ms. Moreover, at drain voltage (V ds) of 5 V and gate voltage (V gs) of 0 V, the responsivity (R), specific detectivity (D*) and external quantum efficiency are achieved as 74 A W−1, 2.15 × 1014 cm Hz1/2 W−1 (Jones) and 3.6 × 104%, respectively.

MYCN-amplified neuroblastoma (NB) is characterized by poor prognosis, and directly targeting MYCN has proven challenging. Here, we showed that aldehyde dehydrogenase family 18 member A1 (ALDH18A1) exerts profound impacts on the proliferation, self-renewal, and tumorigenicity of NB cells and is a potential risk factor in patients with NB, especially those with MYCN amplification. Mechanistic studies revealed that ALDH18A1 could both transcriptionally and posttranscriptionally regulate MYCN expression, with MYCN reciprocally transactivating ALDH18A1 and thus forming a positive feedback loop. Using molecular docking and screening, we identified an ALDH18A1-specific inhibitor, YG1702, and demonstrated that pharmacological inhibition of ALDH18A1 was sufficient to induce a less proliferative phenotype and confer tumor regression and prolonged survival in NB xenograft models, providing therapeutic insights into the disruption of this reciprocal regulatory loop in MYCN-amplified NB.