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In this study, 1H magnetic resonance spectroscopy (1H MRS) was used to analyze metabolites in the hippocampus of chronic type 1 diabetes mellitus (T1DM) rats induced by streptozocin and T1DM rats treated with long-term insulin. The results showed that, compared with control rats and insulin-treated T1DM rats, the fasting blood glucose of T1DM rats increased significantly, while the body weight of T1DM rats decreased remarkably (p < 0.05). The contents of myo-inositol (Ins), taurine (Tau) and glutamate (Glu) of T1DM rats were significantly higher than those of control rats (p=0.000, p=0.003, p=0.014, respectively), and the contents of Ins and Tau of insulin-treated T1DM rats were significantly decreased than those in the T1DM diabetic rats (p=0.000, p=0.010, respectively). Contents of Glu and Glx (Glu and glutamine) of insulin-treated T1DM rats were significantly higher than those in the control group (p=0.007, p=0.042, respectively). The metabolite changes of Ins and Tau in hippocampus of T1DM rats are sensitive to insulin treatment.

Based on the scarcity theory, this study focuses on exploring the relationship between the severity of public health emergencies (i.e., COVID-19) and individual irrational consumer behaviors through the serial mediating variables of perceived scarcity (PS) and negative mentality (NM). An online questionnaire was used to collect data from participants in China and we obtained 466 effective (115 male and 351 female) questionnaires in total. The findings showed that the relationship between each pair of factors – perceived pandemic severity, PS, NM, and irrational consumption behaviors – was significantly positive. Although the perception of the severity of this public health emergency did not directly predict irrational consumer behavior, the effect was mediated by PS and NM independently and serially. These findings reveal that people who strongly perceive scarcity and are prone to negative attitudes are more likely to demonstrate irrational consumer behaviors (such as rushing to buy and hoard living supplies) once the public perceives a public health emergency as severe. This effect occurs because the PS that results from the epidemic affects people’s cognition, emotion, and behavior.

In this study, iron oxide (Fe2O3)/graphitic carbon nitride (g-C3N4)/titanium dioxide (TiO2) nanofibers (NFs) were used as an additional layer on photoanode in dye-sensitized solar cells (DSSCs) to improve the photovoltaic performance of DSSCs. The nanofibers were prepared by electrospinning with double jets. The heterogeneous nanofiber composite mainly includes Fe2O3, g-C3N4, and TiO2. The Fe2O3/g-C3N4/TiO2 NFs were characterized by X-ray diffractometer (XRD), and the surface morphology was observed by a field emission scanning electron microscope (Fe-SEM). The electrochemical impedance spectroscopy (EIS) was applied to analyze the impedance of the cell. The incident photon current efficiency (IPCE) measurements were applied to determine the quantum efficiency, and ultraviolet-visible (UV-Vis) spectrophotometer was applied to observe the dye adsorption and absorption wavelength. To understand the performance of the modified photoanodes in DSSCs, we analyzed the photovoltaic parameters. The results suggest that the addition of Fe2O3/g-C3N4/TiO2 NFs is able to improve the conversion efficiency of the modified DSSCs to 4.81%. In addition, the efficiency under different illumination was also analyzed, and the highest conversion efficiency was 6.81% at 30 mW/cm2. [ABSTRACT FROM AUTHOR]

In our study, the dye-sensitized solar cells (DSSCs) with double-layer thin films were fabricated. The active bottom layer of the structure was mainly made of the commercially available titanium dioxide (TiO2) nanoparticles. TiO2 hollow microspheres (THS) were doped into the TiO2 composite material and used as the scattering top layer. The THS prepared by the one-pot hydrothermal method was composed of irregularly arranged nanoparticles. Meanwhile, we also characterized the synthesized hollow TiO2 microspheres by both the scanning electron microscope (FE-SEM) and the X-ray diffractometer (XRD). Besides, we produced DSSCs with different weight percentages (0.5wt%, 1wt%, and 2wt%) of THS photoanodes. The DSSCs based on pure TiO2 showed the short-circuit current (JSC) of 8.33 mA/cm2 and the photovoltaic conversion efficiency (PCE) of 3.75%. The DSSCs manufactured using 1wt%-THS photoanode had JSC of 12.02 mA/cm2 and a PCE of 5.01%. When compared with the JSC and PCE based on pure TiO2 DSSCs, a significant improvement in the structure was observed. [ABSTRACT FROM AUTHOR]

Background The reuniens (Re) and rhomboid (Rh) nuclei (ReRh) of the midline thalamus interconnect the hippocampus and the medial prefrontal cortex. The hippocampus and medial prefrontal cortex are both involved in the acquisition of trace fear conditioning, in which a conditioned stimulus (tone) and an aversive unconditioned stimulus (footshock) are paired but separated in time with a trace interval. Earlier, we demonstrated that ReRh inactivation during trace conditioning impaired the acquisition of cued fear. In contrast, ReRh inactivation during both conditioning and test resulted in heightened fear to tones during retrieval. Because there was a generalized contextual fear on top of heightened fear to tones in the latter experiment, here we aimed to examine the specific importance of the functional ReRh in cued fear and contextual fear through introducing prolonged contextual exposure. Methods The ReRh were pharmacologically inactivated with muscimol (or saline as controls) before each experimental session. Results We showed that although ReRh inactivation before trace fear conditioning impaired the acquisition of cued fear, the animals still acquired a certain level of fear to the tones. However, without the functional ReRh throughout the entire behavioral sessions, these animals showed heightened contextual fear that did not decline much with the passage of time, which generalized to the other context, and fear to tones reoccurred when the tones were presented. Conclusions Our results suggested that functional ReRh are important for proper acquisition and expression of fear to context and tones acquired under trace procedure. [ABSTRACT FROM AUTHOR]

PbTiO3 was used as a dopant and PbTiO3/titanium dioxide (TiO2) nanofibers (NFs) were used as a scattering layer in the photoanode of dye-sensitized solar cell (DSSC). Their effects on the characteristics of the photoanode of DSSC were studied. The DSSC with the modified photoanode by PbTiO3 and PbTiO3/TiO2 NFs was characterized by X-ray diffractometer (XRD), electrochemical impedance spectroscopy (EIS), ${J}$ – ${V}$ characterization, and incident photon current efficiency (IPCE) measurement. The results show that PbTiO3 and PbTiO3/TiO2 NFs can improve the photovoltaic characteristics of DSSC photoanode. The DSSC with modified photoanode by PbTiO3/TiO2 NFs shows better photoelectric conversion efficiency ($\eta $). Compared with the DSSC without modification (TiO2 photoanode), the photovoltaic conversion efficiency ($\eta $) of the DSSC with modified photoanode by PbTiO3/TiO2 NFs has increased by 19%. Based on this research, it can be considered that PbTiO3/TiO2 NFs can be used as one of the candidate materials to improve the photovoltaic performance of DSSCs. [ABSTRACT FROM AUTHOR]

In order to improve the photovoltaic performance of dye-sensitized solar cell (DSSC), graphitic carbon nitride (g-C3N4)/titanium dioxide (TiO2) nanofibers (NFs) are added into the photoanode of DSSC as an additional layer. g-C3N4 is prepared by high-temperature calcination. Through sol–gel method and electrospinning technology, we prepare g-C3N4/TiO2 NFs. The material properties of g-C3N4/TiO2 NFs are characterized through X-ray diffraction (XRD), ultraviolet-visible (UV-Vis), and field emission scanning electron microscope (FE-SEM). From the measurements of electrochemical impedance spectroscopy (EIS), incident photon to current efficiency (IPCE), and ${J}-{V}$ characteristics, the performances of the DSSCs are analyzed, including impedance parameters, short-circuit current density, open-circuit voltage, fill factor, and photoelectric conversion efficiency. The results show that the addition of g-C3N4/TiO2 NFs is able to enhance the photovoltaic performance. The photoelectric conversion efficiency of the modified DSSC is increased to 5.22%. Compared with the photoelectric conversion efficiency of the DSSC without modification (4.11%), it is an increase of 27%. [ABSTRACT FROM AUTHOR]

Abstract Background β-Lapachone has antitumor and wound healing-promoting activities. To address the potential influences of various chemicals on heart development of zebrafish embryos, we previously treated zebrafish embryos with chemicals from a Sigma LOPAC1280™ library and found several chemicals including β-lapachone that affected heart morphogenesis. In this study, we further evaluated the effects of β-lapachone on zebrafish embryonic heart development. Methods Embryos were treated with β-lapachone or dimethyl sulfoxide (DMSO) at 24 or 48 hours post fertilization (hpf) for 4 h at 28°C. Heart looping and valve development was analyzed by whole-mount in situ hybridization and histological analysis. For fractional shortening and wall shear stress analyses, AB and Tg (gata1:DsRed) embryos were recorded for their heart pumping and blood cell circulations via time-lapse fluorescence microscopy. Dextran rhodamine dye injection into the tail reticular cells was used to analyze circulation. Reactive oxygen species (ROS) was analyzed by incubating embryos in 5-(and 6-)-chloromethyl-2',7'-dichloro-dihydrofluorescein diacetate (CM-H2DCFDA) and recorded using fluorescence microscopy. o-Dianisidine (ODA) staining and whole mount in situ hybridization were used to analyze erythrocytes. TUNEL assay was used to examine DNA fragmentation. Results We observed a linear arrangement of the ventricle and atrium, bradycardia arrhythmia, reduced fractional shortening, circulation with a few or no erythrocytes, and pericardial edema in β-lapachone-treated 52-hpf embryos. Abnormal expression patterns of cmlc2, nppa, BMP4, versican, and nfatc1, and histological analyses showed defects in heart-looping and valve development of β-lapachone-treated embryos. ROS production was observed in erythrocytes and DNA fragmentation was detected in both erythrocytes and endocardium of β-lapachone-treated embryos. Reduction in wall shear stress was uncovered in β-lapachone-treated embryos. Co-treatment with the NQO1 inhibitor, dicoumarol, or the calcium chelator, BAPTA-AM, rescued the erythrocyte-deficiency in circulation and heart-looping defect phenotypes in β-lapachone-treated embryos. These results suggest that the induction of apoptosis of endocardium and erythrocytes by β-lapachone is mediated through an NQO1- and calcium-dependent pathway. Conclusions The novel finding of this study is that β-lapachone affects heart morphogenesis and function through the induction of apoptosis of endocardium and erythrocytes. In addition, this study further demonstrates the importance of endocardium and hemodynamic forces on heart morphogenesis and contractile performance.

Abstract Background Traumatic spinal cord injury (SCI) forms a disadvantageous microenvironment for tissue repair at the lesion site. To consider an appropriate time window for giving a promising therapeutic treatment for subacute and chronic SCI, global changes of proteins in the injured center at the longer survival time points after SCI remains to be elucidated. Methods Through two-dimensional electrophoresis (2DE)-based proteome analysis and western blotting, we examined the differential expression of the soluble proteins isolated from the lesion center (LC) at day 1 (acute) and day 14 (subacute) after a severe contusive injury to the thoracic spinal cord at segment 10. In situ apoptotic analysis was used to examine cell apoptosis in injured spinal cord after adenoviral gene transfer of antioxidant enzymes. In addition, administration of chondroitinase ABC (chABC) was performed to analyze hindlimb locomotor recovery in rats with SCI using Basso, Beattie and Bresnahan (BBB) locomotor rating scale. Results Our results showed a decline in catalase (CAT) and Mn-superoxide dismutase (MnSOD) found at day 14 after SCI. Accordingly, gene transfer of SOD was introduced in the injured spinal cord and found to attenuate cell apoptosis. Galectin-3, β-actin, actin regulatory protein (CAPG), and F-actin-capping protein subunit β (CAPZB) at day 14 were increased when compared to that detected at day 1 after SCI or in sham-operated control. Indeed, the accumulation of β-actin+ immune cells was observed in the LC at day 14 post SCI, while most of reactive astrocytes were surrounding the lesion center. In addition, chondroitin sulfate proteoglycans (CSPG)-related proteins with 40-kDa was detected in the LC at day 3-14 post SCI. Delayed treatment with chondroitinase ABC (chABC) at day 3 post SCI improved the hindlimb locomotion in SCI rats. Conclusions Our findings demonstrate that the differential expression in proteins related to signal transduction, oxidoreduction and stress contribute to extensive inflammation, causing time-dependent spread of tissue damage after severe SCI. The interventions by supplement of anti-oxidant enzymes right after SCI or delayed administration with chABC can facilitate spinal neural cell survival and tissue repair.