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Cubic phase Ca9-xAl6O18:xEu3+ red phosphors have been successfully fabricated using the hydrothermal assisted solid state method. The atomic site occupation of the matrix, morphology, luminescent properties, quenching mechanisms, and thermal stabilities are investigated. The possible sites of Eu3+ in a matrix crystal lattice are investigated via formation energy using first principle calculations. Under 395 nm excitation, Ca9-xAl6O18:xEu3+ shows a red emission at 618 and orange emission at 594 nm and the optimal Eu3+ ion concentration is x = 0.06. The effect of the reaction solution composition on the morphology and emission spectra are investigated using SEM and photoluminescence (PL) spectrum measurements. The results reflect that the samples have different morphologies in different reaction solutions. Additionally, the PL intensities of Ca8.94Al6O18:0.06Eu3+ decreased to 80.6% as the temperature increased from room temperature to 150 °C. Ca9Al6O18:Eu3+ phosphors may potentially be used for white LEDs.

Objective Identification of state-independent and -dependent neural biomarkers may provide insight into the pathophysiology and effective treatment of major depressive disorder (MDD), therefore we aimed to investigate the state-independent and -dependent topological alterations of MDD. Method Brain resting-state functional magnetic resonance imaging (fMRI) data were acquired from 59 patients with unmedicated first episode current MDD (cMDD), 48 patients with remitted MDD (rMDD) and 60 demographically matched healthy controls (HCs). Using graph theory, we systematically studied the topological organization of their whole-brain functional networks at the global and nodal level. Results At a global level, both patient groups showed decreased normalized clustering coefficient in relative to HCs. On a nodal level, both patient groups showed decreased nodal centrality, predominantly in cortex-mood-regulation brain regions including the dorsolateral prefrontal cortex, posterior parietal cortex and posterior cingulate cortex. By comparison to cMDD patients, rMDD group had a higher nodal centrality in right parahippocampal gyrus. Limitations The present study, an exploratory analysis, may require further confirmation with task-based and experimental studies. Conclusions Deficits in the topological organization of the whole brain and cortex-mood-regulation brain regions in both rMDD and cMDD represent state-independent biomarkers.

Background It has been proposed that state-independent, or trait, neurobiological alterations across illness phases may contribute to the high recurrence of major depressive disorder (MDD). Although intrinsic brain network abnormalities have been implicated consistently in MDD neuropathology, MDD state-independent and -dependent resting-state network alterations have not been clearly studied. Methods Resting-state functional magnetic resonance imaging (fMRI) data were collected from 57 medication-naive first-episode current MDD patients, 35 remitted MDD patients, and 66 healthy controls (HCs). Independent component analysis (ICA) was used to extract subnetworks of the default mode network (DMN), central executive network (CEN), and salience network (SN). Results Relative to HCs, the current MDD and remitted MDD groups had decreased intra-intrinsic functional connectivity (iFC) in the dorsal lateral prefrontal cortex (dlPFC) of the left CEN, increased inter-FC between the SN and right CEN (rCEN), and decreased inter-FC between the anterior DMN (aDMN) and rCEN. The altered intra-iFC in the left CEN were correlated negatively with the depressive level in the remitted MDD. Conclusions Hypoactivity of the dlPFC in the left CEN, increased inter-FC between the SN and rCEN, and decreased inter-FC between the aDMN and rCEN may reflect state-independent biomarkers of MDD.

Human risk tolerance is highly idiosyncratic and individuals often show distinctive preferences when faced with similar risky situations. However, the neural underpinnings of individual differences in risk-taking remain unclear. Here we combined structural and perfusion MRI and examined the associations between brain anatomy and individual risk-taking behavior/risk tolerance in a sample of 115 healthy participants during the Balloon Analogue Risk Task, a well-established sequential risky decision paradigm. Both whole brain and region-of-interest analyses showed that the left cerebellum gray matter volume (GMV) has a strong association with individual risk-taking behavior and risk tolerance, outperforming the previously reported associations with the amygdala and right posterior parietal cortex (PPC) GMV. Left cerebellum GMV also accounted for risk tolerance and risk-taking behavior changes with aging. However, regional cerebral blood flow (CBF) provided no additional predictive power. These findings suggest a novel cerebellar anatomical contribution to individual differences in risk tolerance. Further studies are necessary to elucidate the underestimated important role of cerebellum in risk-taking.

In this paper, the volume-of-fluid (VOF) model is adopted to simulate the distribution and flow of a liquid film on the outer surface of the horizontal tube of a falling-film evaporator. The plain tube diameter and the spray distance are 25.4 and 22 mm respectively. The temporal variation characteristics of inline jet flow, the adjacent liquid column, and the steady-state film thickness distribution over the horizontal tubes are analyzed. To better compare with the experimental results, two kinds of numerical simulation medium, water and ethylene glycol, are chosen. The results of the 3-D numerical simulations and experiment are in good agreement. The results show that the jet flow can be divided into inline jet flow and staggered jet flow. Furthermore, a trough forms between the adjacent liquid columns under inline jet flow, whereas a crest forms between the adjacent liquid columns under staggered jet flow. In addition, the liquid viscosity is a crucial factor affecting the spreading of the liquid film. The appearance of the crest between adjacent liquid columns results in staggered jet flow.

This paper examines design optimization of a three-dimensional diffusing S-duct using a modified k–ω shear stress transport (SST) turbulent model as a turbulence prediction method. According to based-Reynolds-stress and based-separation ideas, a robust solution procedure for the model is described and a grid convergence study is presented. An automated system employs this model to design an S-duct. The aerodynamic performances of the optimal duct are investigated in on-design and off-design conditions. It is shown that the sensitivity of the modified model with respect to shape variations allows its use in the design system. Using a multi-objective optimization strategy, this design system significantly improves aerodynamic performance of the S-duct and has low computation cost and excellent design efficiency. The centerline's curvature and the cross-sectional area ratio become reasonable to avoid overexpansion of the optimal duct. Compared with the original design, the flow distortion coefficient of the optimal duct is reduced by 16.3% and the total pressure recovery factor is increased by 1.1% in on-design condition.

Background The hopelessness theory of depression posits that individuals with negative cognitive styles are at risk of developing depression following negative life events. The purpose of this work was to examine whether individuals with cognitive vulnerability to depression (CVD) exhibit similar spontaneous brain activity patterns as compared to patients with major depressive disorder (MDD). Methods Subjects with CVD (N=32), drug-naive first-episode patients with major depressive disorder (N=32), and sex-, age- and education-matched healthy controls (HCs; N=35) were subjected to resting state functional magnetic resonance imaging (RS-fMRI) and amplitudes of low-frequency fluctuation (ALFF) was compared between the groups. Pearson correlation analysis was performed between regional ALFFs and psychometric scores, namely the Cognitive Style Questionnaire (CSQ) and the Center for Epidemiologic Studies Depression (CES-D) scale scores. Results Significant group differences in ALFF values were observed bilaterally in the orbitofrontal cortex (OFC) and insular cortex (IC), and in the left fusiform gyrus (FFG). Compared to HCs, CVD subjects had reduced ALFFs in the bilateral OFC and increased ALFF in the bilateral IC and the left FFG, which were similar to the differences observed between the HCs and MDD patients. Compared to MDD patients, CVD subjects showed significant reduced ALFF values in right IC. Additionally, CSQ scores for the CVD group correlated with ALFF values in the left IC. Limitations We did not conduct a longitudinal study. Our findings were limited in cross-sectional analysis. Conclusions A hypoactive OFC and hyperactive IC in a resting-state may underlie an imbalance in the spontaneous brain activity in orbitofrontal-insular circuits, and these differences may represent a trait-related marker of vulnerability to depression.

Summary The metabolic properties of leukemia-initiating cells (LICs) in distinct bone marrow niches and their relationships to cell-fate determinations remain largely unknown. Using a metabolic imaging system with a highly responsive genetically encoded metabolic sensor, SoNar, we reveal that SoNar-high cells are more glycolytic, enriched for higher LIC frequency, and develop leukemia much faster than SoNar-low counterparts in an MLL-AF9-induced murine acute myeloid leukemia model. SoNar-high cells mainly home to and locate in the hypoxic endosteal niche and maintain their activities through efficient symmetric division. SoNar can indicate the dynamics of metabolic changes of LICs in the endosteal niche. SoNar-high human leukemia cells or primary samples have enhanced clonogenic capacities in vitro or leukemogenesis in vivo. PDK2 fine-tunes glycolysis, homing, and symmetric division of LICs. These findings provide a unique angle for the study of metabolisms in stem cells, and may lead to development of novel strategies for cancer treatment.

The present study examines the inhibitory function of patients with obsessive-compulsive disorder (OCD) involved in semantic conflict using event-related potentials (ERPs). EPRs were recorded in a group of 18 medicine-free OCD patients and 18 normal controls using a modified Stroop paradigm in which the participants were asked to make a judgment of congruent or incongruent stimuli. The reaction time to color-word incongruent stimuli in the OCD group was significantly longer than the reaction time to congruent stimuli. In the OCD group, a significant negativity shift was discovered in P350 amplitude and N450 amplitude in response to incongruent stimuli, a shift not present in the control group. The amplitude of difference waveform was significantly higher for OCD than for control subjects. The findings probably revealed an inhibitory deficit in patients with OCD when performing semantic conflict tasks. The results suggest that this type of inhibitory deficit may be the cause of increased Stroop effects in patients with OCD, and one of contributors to the pathophysiology of OCD.

Background The hopelessness theory of depression posits that individuals with negative cognitive styles are at an increased risk for depression following negative life events. In neuroimaging studies, brain gray matter volume abnormalities correlate with the presence of depressive disorders. However, it is unknown whether changes in gray matter volume also appear in healthy individuals with cognitive vulnerability to depression (CVD). Methods 30 subjects diagnosed with CVD, 33 first-episode patients with major depressive disorder (MDD), and 32 healthy controls were examined using voxel-based morphometry following magnetic resonance imaging (MRI). Results We found significant volumetric differences between three groups in the left precentral gyrus, right fusiform gyrus and the right thalamus. In these regions, compared to controls, CVD subjects showed reduced gray matter volumes in the left precentral gyrus and right fusiform gyrus. MDD patients demonstrated reduced gray matter volume in the left precentral gyrus and increased gray matter volume in the right thalamus. Additionally, CVD individuals had significantly smaller right fusiform gyrus and right thalamus than MDD patients. The weakest-link scores on CSQ were negatively correlated with gray matter volumes in the left precentral gyrus. Conclusions Reductions in brain gray matter volume exist widely in individuals with CVD. In addition, there exist similar abnormalities in gray matter volume in both CVD subjects and MDD patients. Reductions of gray matter volume in the left precentral gyrus might be correlated to the negative cognitive styles, as well as an increased risk for depression.