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1.
Brief Bioinform ; 25(5)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39175132

RESUMEN

Numerous studies have demonstrated that microRNAs (miRNAs) are critically important for the prediction, diagnosis, and characterization of diseases. However, identifying miRNA-disease associations through traditional biological experiments is both costly and time-consuming. To further explore these associations, we proposed a model based on hybrid high-order moments combined with element-level attention mechanisms (HHOMR). This model innovatively fused hybrid higher-order statistical information along with structural and community information. Specifically, we first constructed a heterogeneous graph based on existing associations between miRNAs and diseases. HHOMR employs a structural fusion layer to capture structure-level embeddings and leverages a hybrid high-order moments encoder layer to enhance features. Element-level attention mechanisms are then used to adaptively integrate the features of these hybrid moments. Finally, a multi-layer perceptron is utilized to calculate the association scores between miRNAs and diseases. Through five-fold cross-validation on HMDD v2.0, we achieved a mean AUC of 93.28%. Compared with four state-of-the-art models, HHOMR exhibited superior performance. Additionally, case studies on three diseases-esophageal neoplasms, lymphoma, and prostate neoplasms-were conducted. Among the top 50 miRNAs with high disease association scores, 46, 47, and 45 associated with these diseases were confirmed by the dbDEMC and miR2Disease databases, respectively. Our results demonstrate that HHOMR not only outperforms existing models but also shows significant potential in predicting miRNA-disease associations.


Asunto(s)
MicroARNs , MicroARNs/genética , Humanos , Biología Computacional/métodos , Predisposición Genética a la Enfermedad , Algoritmos , Neoplasias de la Próstata/genética , Modelos Genéticos
2.
Nano Lett ; 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39475118

RESUMEN

Optical metasurfaces have revolutionized analog computing and image processing at subwavelength scales with faster speed and lower power consumption. They typically involve spatial differentiation with an engineered angular dispersion. Quasi-bound states in the continuum (quasi-BICs) have emerged as powerful tools for customizing optical resonances. While quasi-BICs have been widely used with high Q-factors and enhanced field confinement, their potential in image processing remains unexplored. Here, we demonstrate edge detection imaging by leveraging quasi-BIC in an all-dielectric metasurface. This metasurface, composed of four nanodisks per unit cell, supports a polarization-independent quasi-BIC through structural perturbations, allowing simultaneously engineering Q-factor and angular dispersion. It can perform isotropic two-dimensional spatial differentiation, which is crucial for edge detection. We fabricate the metasurfaces and validate their efficient, high-quality edge detection under different polarizations. Our findings illuminate the mechanisms of edge detection with quasi-BIC metasurfaces, opening new avenues for ultracompact, low-power optical computing devices.

3.
Biochem Biophys Res Commun ; 729: 150343, 2024 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-38986259

RESUMEN

Pathological cardiac hypertrophy is associated with adverse cardiovascular events and can gradually lead to heart failure, arrhythmia, and even sudden death. However, the current development of treatment strategies has been unsatisfactory. Therefore, it is of great significance to find new and effective drugs for the treatment of myocardial hypertrophy. We found that carnosol can inhibit myocardial hypertrophy induced by PE stimulation, and the effect is very significant at 5 µM. Moreover, we demonstrated that 50 mg/kg of carnosol protect against cardiac hypertrophy and fibrosis induced by TAC surgery in mice. Mechanically, we proved that the inhibitory effect of carnosol on cardiac hypertrophy depends on its regulation on the phosphorylation activation of AMPK. In conclusion, our study suggested that carnosol may be a novel drug component for the treatment of pathological cardiac hypertrophy.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Abietanos , Cardiomegalia , Ratones Endogámicos C57BL , Miocitos Cardíacos , Animales , Abietanos/farmacología , Abietanos/uso terapéutico , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/metabolismo , Cardiomegalia/patología , Cardiomegalia/prevención & control , Proteínas Quinasas Activadas por AMP/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Masculino , Ratones , Transducción de Señal/efectos de los fármacos , Fosforilación/efectos de los fármacos , Activación Enzimática/efectos de los fármacos
4.
Opt Lett ; 49(19): 5607-5610, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39353017

RESUMEN

Interaction of light in the high-numerical aperture (high-NA) systems is crucial for theoretical advances and applications such as superresolution imaging and optical nanofabrication. High coherence is demanded at this scale for intensity and spin profile sculpturing, since the underlying physics being wave interference. Here we report that, even for low-coherence light, 3D light features in a nanometer range can be generated by employing structured coherence states of the light beam in a high-NA resonator system. The generated structures, e.g., 3D helix intensity and transverse spin texture, can survive in rather incoherent optical fields at nanoscale. We also found that, counterintuitively, despite the substantial decrease in spatial coherence of the light field, the longitudinal electric field component and transverse spin density are instead enhanced. The applications of the observed twisted spectral density and spin structures may range from high-resolution imaging to metrology.

5.
Opt Lett ; 49(18): 5308-5311, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39270292

RESUMEN

Compared with symmetric directional couplers (DCs), asymmetric DCs constructed by two or over two different parallel waveguides offer a more flexible structure and allow for easier expansion of mode channels. In this Letter, we propose a kind of asymmetric topological DC based on two different valley photonic crystal waveguides (VPCWs). According to the coupled-mode theory, phase matching induces the complete coupling for the guide modes of two different VPCWs, whereas significant phase mismatching indicates no coupling occurs. Furthermore, the asymmetric topological DCs exhibit backscattering immunity and anti-disturbance robustness owing to the topological edge states (TESs), which greatly improve the performance of asymmetric DCs. We further design a new, to the best of our knowledge, kind of topological polarization beam splitter (TPBS) at the communication wavelength of 1550 nm by ensuring that the transverse electric mode satisfies the phase matching condition, while the transverse magnetic mode is phase-mismatched. The simulated results demonstrate that the proposed TPBS exhibits highly effective polarization separation and is robust against defects. This design holds significant potential for applications in optical communication systems.

6.
Opt Lett ; 48(17): 4432-4435, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37656521

RESUMEN

Following recent work [Sci. China Phys. Mech. Astron.66, 274213 (2023)10.1007/s11433-023-2097-9] that revealed the sub-wavelength scale resonance phenomenon in scalar random beams counterpropagating in an open-end cavity, we extend the analysis to the vectorial domain and show a similar effect for the polarization properties. We found that, in contrast with the changes in the scalar properties, being of harmonic nature, changes in polarization involve alternating regions of constant values followed by sharp and complex changes.

7.
Opt Lett ; 44(4): 735-738, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30767974

RESUMEN

Optical twists are the rotation of light structures along the beam axis, which can be caused by the quadratic twist phase of a partially coherent field. Here, we introduce a new class of partially coherent beams whose spectral density and degree of coherence tend to rotate during propagation. Unlike the previously reported twisted Gaussian Schell-model beams, this family of rotating beams is constructed without the framework of rotationally invariant cross-spectral density functions. Thus, these beams have different underlying physics and exhibit distinctive twist effects. It is shown that such beams can undergo a twist of more than 90 deg, providing larger degrees of freedom for flexibly tailoring the beam twist. Our results may pave the way toward synthesizing rotating beams for applications in optics and, in particular, inspire further studies in the field of twist phase proposed 25 years ago.

8.
Opt Lett ; 44(19): 4714-4717, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31568424

RESUMEN

A new, to the best of our knowledge, family of partially coherent beams incorporating a set of nonseparable phases is introduced. Due to the nonnegative definiteness of the cross-spectral density function, these phases cannot survive in the limit of full coherence, which distinguishes them from conventional phase terms. An example of a nonuniform model beam with a quartic nonseparable phase is presented. It is shown that the presence of such a phase in effect stretches the beam in a specific direction upon propagation. In particular, the interplay between the magnitude and phase of the source coherence state endows the beam with a wing-like structure. The fundamental concept developed here brings into evidence the countless nonseparable phases differing from twist, and can be exploited to generate customized partially coherent beams for applications in optics.

9.
Opt Express ; 26(2): 2168-2180, 2018 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-29401941

RESUMEN

A novel class of partially coherent light sources termed optical coherence grids (OCGs) are introduced that can yield stable optical grids in the far field. The optical grids, of which the light distributes in a network of straight lines crossing each other to form a series of hollow cages, can be seen as a better controlled optical lattice. Propagation properties of OCG beams in free space, including spectral density, transverse coherence, and M2 factor, are investigated in detail. It is interesting that a periodic grid pattern is produced at a distance and remains stable on further propagation, and we stress that the structure of far-field optical grids can be flexibly tuned by modulating the correlation parameters of the source. In addition, by performing convolution of degree of coherence, we also propose perfect optical coherence grids (POCG). The far-field grid pattern of POCG is in a fully controllable fashion. This work is expected to find applications in cooling atoms, trapping microscopic particles, or assembling cells, etc.

10.
Opt Lett ; 43(15): 3554-3557, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30067708

RESUMEN

We introduce, to the best of our knowledge, a new class of twisted partially coherent sources for producing rotating Gaussian array profiles. The general analytical formula for the cross-spectral density function of a beam generated by such a novel source propagating in free space is derived, and its propagation characteristics are analyzed. It is shown that both the irradiance profile of each element of the array and the degree of coherence rotate during propagation, but in opposite directions. Further, the twist effects of the spectral density and the degree of coherence are quantified. It is shown that the direction of rotation is changeable upon propagation. Our results may provide new insight into the twist phase and may be applied in optical trapping.

11.
Animals (Basel) ; 14(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38473057

RESUMEN

The Wushan Salamander (Liua shihi), Jinfo Salamander (Pseudohynobius jinfo), and Wenxian Knobby Salamander (Tylototriton wenxianensis) are rare national Class II protected wild animals in China. We performed MaxEnt modeling to predict and analyze the potential distribution and trends of these species in Chongqing under current and future climate conditions. Species distribution data were primarily obtained from field surveys, supplemented by museum collections and the existing literature. These efforts yielded 636 records, including 43 for P. jinfo, 23 for T. wenxianensis, and 570 for L. shihi. Duplicate records within the same 100 m × 100 m grid cell were removed using ENMTools, resulting in 10, 12, and 58 valid distribution points for P. jinfo, T. wenxianensis, and L. shihi, respectively. The optimization of feature class parameters (FC) and the regularization multiplier (RM) were applied using R package "ENMeval 2.0" to establish the optimal model with MaxEnt. The refined models were applied to simulate the suitable distribution areas for the three species. The results indicate that the current suitable habitat area for L. shihi accounted for 9.72% of the whole region of the Chongqing municipality. It is projected that, by 2050, the proportion of suitable habitat will increase to 12.54% but will decrease to 11.98% by 2070 and further decline to 8.80% by 2090. The current suitable habitat area for P. jinfo accounted for 1.08% of the whole region of the Chongqing municipality, which is expected to decrease to 0.31%% by 2050, 0.20% by 2070, and 0.07% by 2090. The current suitable habitat area for T. wenxianensis accounted for 0.81% of the whole region of the Chongqing municipality, which is anticipated to decrease to 0.37% by 2050, 0.21% by 2070, and 0.06% by 2090. Human disturbance, climate variables, and habitat characteristics are the primary factors influencing the distribution of three salamander species in Chongqing. The proximity to roads significantly impacts L. shihi, while climate conditions mainly affect P. jinfo, and the distance to water sources is crucial for T. wenxianensis. The following suggestions were made based on key variables identified for each species: (1) For L. shihi, it is imperative to minimize human disturbances and preserve areas without roads and the existing vegetation within nature reserves to ensure their continued existence. (2) For P. jinfo, the conservation of high-altitude habitats is of utmost importance, along with the reduction in disturbances caused by roads to maintain the species' ecological niche. (3) For T. wenxianensis, the protection of aquatic habitats is crucial. Additionally, efforts to mitigate the impacts of road construction and enhance public awareness are essential for the preservation of this species and the connectivity of its habitats.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38606193

RESUMEN

Deep-learning techniques have been used widely to alleviate the labour-intensive and time-consuming manual annotation required for pixel-level tissue characterization. Our previous study introduced an efficient single dynamic network - Omni-Seg - that achieved multi-class multi-scale pathological segmentation with less computational complexity. However, the patch-wise segmentation paradigm still applies to Omni-Seg, and the pipeline is time-consuming when providing segmentation for Whole Slide Images (WSIs). In this paper, we propose an enhanced version of the Omni-Seg pipeline in order to reduce the repetitive computing processes and utilize a GPU to accelerate the model's prediction for both better model performance and faster speed. Our proposed method's innovative contribution is two-fold: (1) a Docker is released for an end-to-end slide-wise multi-tissue segmentation for WSIs; and (2) the pipeline is deployed on a GPU to accelerate the prediction, achieving better segmentation quality in less time. The proposed accelerated implementation reduced the average processing time (at the testing stage) on a standard needle biopsy WSI from 2.3 hours to 22 minutes, using 35 WSIs from the Kidney Tissue Atlas (KPMP) Datasets. The source code and the Docker have been made publicly available at https://github.com/ddrrnn123/Omni-Seg.

13.
JMIR Public Health Surveill ; 9: e46991, 2023 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-37747776

RESUMEN

BACKGROUND: Although many studies have reported on the associations between the amount of physical activity (PA) and the transitions of cardiometabolic multimorbidity (CMM), the evidence for PA intensity has not been fully evaluated. OBJECTIVE: This study aimed to explore the impact of PA intensity on the dynamic progression of CMM. METHODS: The prospective cohort of this study using data from the UK Biobank included 359,773 participants aged 37-73 years who were recruited from 22 centers between 2006 and 2010. The diagnoses of CMM, which included the copresence of type 2 diabetes (T2D), ischemic heart disease, and stroke, were obtained from first occurrence fields provided by the UK Biobank, which included data from primary care, hospital inpatient record, self-reported medical condition, and death registers. The PA intensity was assessed by the proportion of vigorous PA (VPA) to moderate to vigorous PA (MVPA). Multistate models were used to evaluate the effect of PA intensity on the dynamic progression of CMM. The first model (model A) included 5 transitions, namely free of cardiometabolic disease (CMD) to first occurrence of CMD (FCMD), free of CMD to death, FCMD to CMM, FCMD to mortality, and CMM to mortality. The other model (model B) used specific CMD, namely T2D, ischemic heart disease, and stroke, instead of FCMD and included 11 transitions in this study. RESULTS: The mean age of the included participants (N=359,773) was 55.82 (SD 8.12) years at baseline, and 54.55% (196,271/359,773) of the participants were female. Compared with the participants with no VPA, participants with intensity levels of >0.75 to <1 for VPA to MVPA had a 13% and 27% lower risk of transition from free of CMD to FCMD (hazard ratio [HR] 0.87, 95% CI 0.83-0.91) and mortality (HR 0.73, 95% CI 0.66-0.79) in model A, respectively. The HR for the participants with no moderate PA was 0.82 (95% CI 0.73-0.92) compared with no VPA. There was a substantially protective effect of higher PA intensity on the transitions from free of CMD to T2D and from T2D to mortality, which reveals the importance of PA intensity for the transitions of T2D. More PA and greater intensity had a synergistic effect on decreasing the risk of the transitions from free of CMD to FCMD and mortality. Male participants, younger adults, adults with a higher BMI, current or previous smokers, and excessive alcohol drinkers could obtain more benefits from higher PA intensity for the lower risk of at least 1 transition from free of CMD, then to CMM, and finally to mortality. CONCLUSIONS: This study suggests that higher PA intensity is an effective measure for preventing CMM and mortality in the early period of CMM development. Relevant interventions related to higher PA intensity should be conducted.


Asunto(s)
Diabetes Mellitus Tipo 2 , Isquemia Miocárdica , Accidente Cerebrovascular , Adulto , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , Diabetes Mellitus Tipo 2/epidemiología , Multimorbilidad , Bancos de Muestras Biológicas , Ejercicio Físico , Isquemia Miocárdica/epidemiología , Reino Unido/epidemiología
14.
J Affect Disord ; 328: 238-244, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36806594

RESUMEN

BACKGROUND: Adolescents with daytime sleepiness have been demonstrated to have a higher level of suicidal risk than those without. Currently, few studies had examined the pathway from daytime sleepiness to suicidal risk among female adolescents. This study aimed to explore the association among menstrual pain, daytime sleepiness, and suicidal risk among female adolescents in China. METHODS: Of 7072 adolescents who participated in the follow-up survey of Shandong Adolescents Behavior & Health Cohort (SABHC), 3001 were female adolescents who had begun to menstruate and included for the analysis. A structured self-administrated questionnaire was used to measure menstrual pain, daytime sleepiness, suicidal risk and demographic characteristics. Participants were first surveyed in November-December 2015 and resurveyed 1 year later. RESULTS: Of 3001 participants, 11.43 % had suicidal risk, 79.8 % experienced menstrual pain. Cross-lagged analysis showed that there was cause-and-effect relationship between menstrual pain and daytime sleepiness. Moderate (OR = 1.79, 95%CI: 1.22-2.63) and severe (OR = 2.73, 95%CI: 1.80-4.12) menstrual pain (follow-up) were associated with suicidal risk (follow-up). Daytime sleepiness (baseline: OR = 1.04, 95%CI: 1.02-1.06, follow-up: OR = 1.07, 95%CI: 1.05-1.09) had effects on suicidal risk (follow-up). Mediation analysis showed that menstrual pain played a partially mediating role between daytime sleepiness and suicidal risk, with the indirect effect being 0.002 (95%CI: 0.001-0.004). LIMITATIONS: All data were self-reported. CONCLUSIONS: Menstrual pain and daytime sleepiness had effects on each other, and they both were the risk factors of suicidal risk. Among female adolescents, the association between daytime sleepiness and suicidal risk could be partially mediated by menstrual pain. Releasing the menstrual pain of female adolescents with daytime sleepiness could reduce their suicidal risk.


Asunto(s)
Trastornos de Somnolencia Excesiva , Dismenorrea , Adolescente , Humanos , Femenino , Masculino , Estudios Prospectivos , Ideación Suicida , Encuestas y Cuestionarios
15.
Naunyn Schmiedebergs Arch Pharmacol ; 396(10): 2519-2528, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37178274

RESUMEN

Orientin is a flavone isolated from medicinal plants used in traditional Chinese medicine (TCM) that suppresses the growth of cancer cells in vitro. The effects of orientin in hepatoma carcinoma cells remain unknown. The aim of this paper is to investigate the effects of orientin on the viability, proliferation, and migration of hepatocellular carcinoma cells in vitro. In this study, we found that orientin could inhibit the proliferation, migration, and the activation of NF-κB signaling pathway in hepatocellular carcinoma cells. An activator of NF-κB signaling pathway, PMA, could abolish the inhibitory effect of orientin on NF-κB signaling pathway and proliferation and migration of Huh7 cells. These findings raise the possibility that orientin can be used in the treatment of hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , FN-kappa B/metabolismo , Neoplasias Hepáticas/patología , Proliferación Celular , Línea Celular Tumoral
16.
J Affect Disord ; 305: 213-219, 2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35278486

RESUMEN

BACKGROUND: Non-suicidal self-injury (NSSI) is a significant public health concern. Authoritarian parenting is a common parenting style in China. Authoritarian parenting is associated with NSSI in adolescents. Little is known about the mechanism underlying this association. This study was to investigate the mediating effect of depressive symptoms on the association between maternal authoritarian parenting and NSSI among Chinese adolescents. METHODS: A total of 7072 adolescents who participated in the 1-year follow-up of Shandong Adolescent Behavior & Health Cohort (SABHC) were included for the analysis. A self-administered questionnaire was used to assess authoritarian parenting, depressive symptoms, non-suicidal self-injury, and family demographics in November-December in 2015. One year later, a follow-up survey was carried out to assess participants' depressive symptoms and NSSI. RESULTS: Of the sample, mean age was 14.58 (SD = 1.46) and 3536 (50%) were female at baseline. 19.4% adolescents reported having ever NSSI over the past 12 months at baseline, and 8.8% reported having ever NSSI at 1-year follow-up. The association of maternal authoritarian parenting with subsequent NSSI was at least partially mediated by depressive symptoms. Mediation analyses showed that effect size was 0.194 in the entire sample, 0.192 in females and 0.193 in males, respectively. LIMITATION: All variables were measured based on self-report. CONCLUSIONS: Maternal authoritarian parenting style is a significant predictor of NSSI and its association with NSSI is partially mediated by depressive symptoms among Chinese adolescents. It may be important to intervene poor parenting styles and depression to reduce the risk of NSSI in Chinese adolescents.


Asunto(s)
Conducta del Adolescente , Conducta Autodestructiva , Adolescente , China/epidemiología , Depresión/epidemiología , Femenino , Humanos , Masculino , Responsabilidad Parental , Conducta Autodestructiva/epidemiología
17.
J Affect Disord ; 302: 234-240, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35090945

RESUMEN

OBJECTIVE: Little is known about the association between perceived social support (PSS) and suicidal ideation in Chinese adolescents. This study was to examine the association of perceived social support and suicidal ideation (SI) and the mediating role of depressive symptoms in a large sample of adolescents in China. METHOD: A total of 11,831 adolescents who participated in the baseline Shandong Adolescent Behavior & Health Cohort were included for analysis. Perceived social support, depressive symptoms, and other variables were assessed by a self-administrated questionnaire. Path analysis was used to estimate the association between PSS, depressive symptoms, and suicidal ideation. RESULTS: The prevalence rate of SI in the past year was 12.5%. Suicidal ideation and depressive symptoms were significantly associated with low PSS from family, friends, and significant others. Path analysis revealed that depressive symptoms partially mediated the relationship between PSS from family, friends, and significant others and suicidal ideation. After controlling for covariates, the mediation effect proportion of depressive symptoms on the associations between perceived social support from family, friends, and significant others and SI ranged from 19.20% to 62.12%. LIMITATIONS: As this is a cross-sectional study, no causal relationship could be made. CONCLUSIONS: Depressive symptoms partially mediated the association between perceived social support and suicidal ideation. Longitudinal research is needed to better understand the association between social support and suicidal ideation in adolescents.


Asunto(s)
Depresión , Ideación Suicida , Adolescente , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Humanos , Factores de Riesgo , Apoyo Social
18.
J Affect Disord ; 314: 365-371, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35878828

RESUMEN

BACKGROUND: Prolonged mobile phone use has been demonstrated to be associated with mental health problems and suicidal behavior in adolescents. This study examined the mediating role of depressive symptoms in the association between duration of mobile phone use (DMPU) and suicidal behavior in adolescents. METHODS: A total of 6,923 participants from the Shandong Adolescent Behavior & Health Cohort (SABHC) were included in the analysis. Participants completed a self-administered questionnaire to assess DMPU on weekdays and weekends, mental disorders, insomnia symptoms, depressive symptoms, suicidal behavior (thought, plan, or attempt), and family demographics in November-December 2015. One year later, a follow-up survey was conducted to ask participants to report their depressive symptoms and suicidal behavior. Path analyses with logistic regressions were performed to examine the mediating role of depressive symptoms in the DMPU-suicidal behavior link. RESULTS: Of the sample, mean age was 14.58 (SD = 1.45) and 3,455 (49.9 %) were female at baseline. 12.12 % of participants reported having ever suicidal behavior during the past 12 months at baseline, and 10.63 % reported having ever suicidal behavior during 1-year follow-up. Path analyses showed that the depressive symptoms played a partial mediating role in the association of DMPU on weekdays and weekends with subsequent suicidal behavior. After controlling for covariates, depressive symptoms accounted for 33.6 % and 58.6 % of the total effect of DMPU on weekdays and weekends on suicidal behavior, respectively. LIMITATION: All variables were measured based on self-report. CONCLUSIONS: The link between DMPU and suicidal behavior was partially mediated by depressive symptoms. Prolonged mobile phone use and depressive symptoms should be assessed and intervened to prevent suicidal behavior in adolescents.


Asunto(s)
Conducta del Adolescente , Uso del Teléfono Celular , Trastornos del Inicio y del Mantenimiento del Sueño , Adolescente , Conducta del Adolescente/psicología , Depresión/epidemiología , Depresión/psicología , Femenino , Humanos , Masculino , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Trastornos del Inicio y del Mantenimiento del Sueño/etiología , Ideación Suicida
19.
ChemSusChem ; 10(5): 930-937, 2017 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-28093899

RESUMEN

LaTiO2 N photocatalysts were prepared by thermal ammonolysis of flux-synthesized La2 Ti2 O7 and La2 TiO5 , and were investigated for water oxidation. Though LaTiO2 N derived from La2 TiO5 appears defect-free by UV/Vis/near-IR and electron paramagnetic resonance (EPR) spectroscopy, its performance is much lower than that of conventional La2 Ti2 O7 -derived LaTiO2 N with defects. It is shown by Mott-Schottky analysis that La2 TiO5 -derived LaTiO2 N has significantly lower donor density; this can result in insufficient built-in electric field for the separation of photogenerated electrons and holes. The lower donor density is also consistent with the smaller difference between the Fermi level and the valence-band maximum, which accounts for a lower oxidative power of the holes. In light of this discovery, the donor density was increased substantially by introducing anion vacancies through annealing in Ar. This resulted in improved performance. The CoOx -assisted La2 TiO5 -derived LaTiO2 N annealed at 713 °C has a higher quantum efficiency (25 %) at 450 nm than high-performance conventional CoOx /LaTiO2 N (21 %).


Asunto(s)
Lantano/química , Óxidos/química , Procesos Fotoquímicos , Titanio/química , Agua/química , Catálisis , Oxidación-Reducción , Temperatura
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