Abstract There is growing evidence that the COVID-19 pandemic has had an impact on the mental health and professional identity of nursing students. This study aimed to explore the trajectories of psychological distress and professional identity and examine their causal relationship among graduate nursing students. A prospective longitudinal study was conducted with 556 graduate nursing students in China who were asked to complete the Questionnaires for Emergent Events of Public Health and the Professional Identity Questionnaire for Nursing Students at three timepoints during the pandemic (T1 = onset of the outbreak, T2 = state-wide isolation, T3 = school reopening). The results showed that psychological distress and psychological identity changed over time, with the lowest psychological distress and highest professional identity at T3. The cross-lagged analysis showed that professional identity at T1 and T2 negatively predicted psychological distress at T2 and T3. We concluded that nurse educators should develop programs and strategies to cultivate professional identity in graduate nursing education to improve mental health during public health crises.

Resumen: Cada vez hay más evidencia de que la reciente epidemia de que la COVID-19 puede afectar a la salud mental y la identidad profesional de los estudiantes de posgrado en enfermería. Es por ello que el propósito de este estudio fue explorar las trayectorias del estrés psicológico y la identidad ocupacional y examinar su relación causal de dichos estudiantes de posgrado durante la nueva epidemia. Se llevó a cabo un estudio prospectivo longitudinal con 556 estudiantes de posgrado en enfermería en China, a los que se les pidió que completaran los cuestionarios de emergencia de salud pública y el de identidad ocupacional para estudiantes de enfermería en tres etapas del brote (T1 = brote, T2 = aislamiento estatal, T3 = reapertura escolar). Los resultados mostraron que estrés psicológico y la identidad psicológica de los estudiantes universitarios habían cambiado con el tiempo. En T3, la perturbación emocional fue la más baja y la identidad ocupacional la más alta. El análisis de retraso cruzado mostró que la identidad ocupacional de T1 y T2 tenía un efecto predictivo negativo sobre la perturbación psicológica de T2 y T3. Conclusión: los educadores de enfermería deberían formular programas y estrategias que cultiven la identidad profesional de sus estudiantes a fin de mejorar la salud mental en emergencias públicas.

Abstract The roles and molecular mechanisms of tumor necrosis factor-α-induced protein 8-like 2 (TIPE2) in periodontitis remain largely unknown. Objective This study aimed to determine the expression of TIPE2 and NF-κB p65 in rat Porphyromonas gingivalis-induced periodontics in vivo. Methodology Periodontal inflammation and alveolar bone resorption were analyzed using western blotting, micro-computed tomography, TRAP staining, immunohistochemistry, and immunofluorescence. THP-1 monocytes were stimulated using 1 μg/ml Pg. lipopolysaccharide (Pg.LPS) to determine the expression of TIPE2 in vitro. TIPE2 mRNA was suppressed by siRNA transfection, and the transfection efficiency was proven using western blotting and real-time PCR. The NF-κB pathway was activated by treating the cells with 1 μg/ml Pg.LPS to explore related mechanisms. Results The expression of both TIPE2 and NF-κB p65 was increased in the gingival tissues of rat periodontitis compared with normal tissues. Positive expression of TIPE2 was distributed in inflammatory infiltrating cells and osteoclasts in the marginal lacunae of the alveolar bone. However, strong positive expression of TIPE2 in THP-1 was downregulated after Pg.LPS stimulation. TIPE2 levels negatively correlated with TNF-α and IL-1β. Decreased TIPE2 in THP-1 further promoted NF-κB p65 phosphorylation. Mechanistically, TIPE2 knockdown upregulated NF-κB signaling pathway activity. Conclusions Taken together, these findings demonstrate that TIPE2 knockdown aggravates periodontal inflammatory infiltration via NF-κB pathway. Interventions aimed at increasing TIPE2 may help in the therapeutic applications for periodontitis.

This meta-analysis was conducted to evaluate the value of indocyanine green (ICG) in guiding sentinel lymph node biopsy (SLNB) for patients with oral cavity cancer. An electronic database search (PubMed, MEDLINE, Cochrane Library, Embase, and Web of Science) was performed from their inception to June 2020 to retrieve clinical studies of ICG applied to SLNB for oral cavity cancer. Data were extracted from 14 relevant articles (226 patients), and 9 studies (134 patients) were finally included in the meta-analysis according to the inclusion and exclusion criteria. The pooled sentinel lymph node (SLN) sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 88.0% (95% confidence interval [CI], 74.0-96.0), 64.0% (95% CI, 61.0-66.0), 2.45 (95% CI, 1.31-4.60), 0.40 (95% CI, 0.17-0.90), and 7.30 (95% CI, 1.74-30.68), respectively. The area under the summary receiver operating characteristic curve was 0.8805. In conclusion, ICG applied to SLNB can effectively predict the status of regional lymph nodes in oral cavity cancer.

The influence of the Nb5+-doped content and the doping CaCO3 on the electrical properties and the microdefects of BSTN ceramics by Positron Annihilation Techniques were studied, which were fired at 1350 ºC for 2 hours in air. The PTCR characteristics in the BSTN samples were also investigated. Moreover, the information on microdefects in BSTN ceramics was demonstrated by coincidence Doppler broadening spectrum measurements and positron annihilation lifetime spectra. Meanwhile, the influence of the defects on the electrical properties of the ceramics was also revealed. Furthermore, the critical donor-dopant content was 0.4 mol%, which corresponding room-temperature resistivity and the resistivity jumping ratio was 714.3 Ω·cm and 2.77 × 102, respectively. In addition, the average positrons annihilate lifetime t of the BSTN ceramics was investigated as well.

The effects of the sintering time on the electrical properties and the positive temperature coefficient of resistance (PTCR) effect of Ba1.006(Ti1-xNbx)O3 (BTN) ceramics were investigated, which were sintered at 1190 ºC for 0.5-6 hours in a reducing atmosphere and then re-oxidized at 800 ºC for 1 hour. The results indicated that the sintering time affected the electrical properties and the PTCR effect of the multilayer BTN samples, whose room-temperature resistance decreased with an increase of the sintering time at same sintering temperature of 1190 ºC. However, the resistance jump first increased and then reduced as a function of the sintering time. Furthermore, The BTN ceramics exhibited a pronounced PTCR effect, with a resistance jump greater by 3.6 orders of magnitude, along with a low RT resistance of 0.14 Ω at a reoxidated temperature of 800 ºC after sintering at 1190 ºC for 2 h in a reducing atmosphere. In addition, the activation energy of samples obtained at different sintering times had also been investigated.

Duplex Ni-P-TiO2/Ni-P coatings were electrodeposited onto brass substrates. High phosphorus Ni-P coatings were plated as the inner layer to improve the corrosion resistance, while low phosphorus sol-enhanced Ni-P-TiO2 coatings were deposited on the top to strengthen the mechanical property. The microstructure, morphology, mechanical property and corrosion resistance of coatings were investigated systematically. The results show that duplex coatings exhibit both excellent mechanical property and good corrosion resistance. The hardness was further improved from ~545 HV50 of duplex Ni-P/Ni-P coating to ~622 HV50 of duplex Ni-P-12.5mL/L TiO2/Ni-P coating, while the hardness of single Ni-P coating was only ~387 HV50. The corrosion resistance of duplex coatings improved significantly by adding a suitable amount of TiO2 sol. Duplex Ni-P-12.5mL/L TiO2/Ni-P coating presented the highest corrosion resistance. However, adding excessive quantities of sol (more than 12.5mL/L) caused nanoparticle agglomeration and created a porous structure in the outer layer, deteriorating the properties of coatings.