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We report the unified constitutive law of vibroconvective turbulence in microgravity, i.e. $Nu \sim a^{-1} Re_{os}^\beta$ where the Nusselt number $Nu$ measures the global heat transport, $a$ is the dimensionless vibration amplitude, $Re_{os}$ is the oscillational Reynolds number and $\beta$ is the universal exponent. We find that the dynamics of boundary layers plays an essential role in vibroconvective heat transport and the $Nu$-scaling exponent $\beta$ is determined by the competition between the thermal boundary layer (TBL) and vibration-induced oscillating boundary layer (OBL). Then a physical model is proposed to explain the change of scaling exponent from $\beta =2$ in the TBL-dominant regime to $\beta = 4/3$ in the OBL-dominant regime. Our finding elucidates the emergence of universal constitutive laws in vibroconvective turbulence, and opens up a new avenue for generating a controllable effective heat transport under microgravity or even microfluidic environment in which the gravity effect is nearly absent.
A simple and effective strategy is proposed for fabricating honeycomb-patterned ethyl cellulose (EC) films via a combination of the dip-coating and breath figure methods under a wide humidity range (40–90%). A mixture of toluene and methanol as a volatile solvent/nonsolvent pair was used to effectively control the surface morphology. Additionally, honeycomb patterns were successfully formed via dip-coating under a low humidity (relative humidity less than 40%), when water was directly added into the mixed solution. The important factors that influenced the morphology of EC honeycomb-patterned films were investigated, such as the humidity, solution concentration, and the withdrawal speed during dip-coating. The pore sizes could be controlled by changing the film-formation conditions. Water contact angle enables a transition from hydrophilic to hydrophobic. The possible mechanisms of honeycomb pattern formation are discussed. The fabrication of an ordered honeycomb-patterned film in a cost-effective and convenient manner will have broad application potential in the future.
Family coaggregation of attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), bipolar disorder (BD), major depressive disorder (MDD) and schizophrenia have been presented in previous studies. The shared genetic and environmental factors among psychiatric disorders remain elusive.
Methods
This nationwide population-based study examined familial coaggregation of major psychiatric disorders in first-degree relatives (FDRs) of individuals with ASD. Taiwan's National Health Insurance Research Database was used to identify 26 667 individuals with ASD and 67 998 FDRs of individuals with ASD. The cohort was matched in 1:4 ratio to 271 992 controls. The relative risks (RRs) and 95% confidence intervals (CI) of ADHD, ASD, BD, MDD and schizophrenia were assessed among FDRs of individuals with ASD and ASD with intellectual disability (ASD-ID).
Results
FDRs of individuals with ASD have higher RRs of major psychiatric disorders compared with controls: ASD 17.46 (CI 15.50–19.67), ADHD 3.94 (CI 3.72–4.17), schizophrenia 3.05 (CI 2.74–3.40), BD 2.22 (CI 1.98–2.48) and MDD 1.88 (CI 1.76–2.00). Higher RRs of schizophrenia (4.47, CI 3.95–5.06) and ASD (18.54, CI 16.18–21.23) were observed in FDRs of individuals with both ASD-ID, compared with ASD only.
Conclusions
The risk for major psychiatric disorders was consistently elevated across all types of FDRs of individuals with ASD. FDRs of individuals with ASD-ID are at further higher risk for ASD and schizophrenia. Our results provide leads for future investigation of shared etiologic pathways of ASD, ID and major psychiatric disorders and highlight the importance of mental health care delivered to at-risk families for early diagnoses and interventions.
We hypothesize that the tumor necrosis factor-α (TNF-α) may play a role in disturbing the effect of selective serotonin reuptake inhibitor (SSRI) on the striatal connectivity in patients with major depressive disorder (MDD).
Methods
We performed a longitudinal observation by combining resting-state functional magnetic resonance imaging (rs-fMRI) and biochemical analyses to identify the abnormal striatal connectivity in MDD patients, and to evaluate the effect of TNF-α level on these abnormal connectivities during SSRI treatment. Eighty-five rs-fMRI scans were collected from 25 MDD patients and 35 healthy controls, and the scans were repeated for all the patients before and after a 6-week SSRI treatment. Whole-brain voxel-wise functional connectivity (FC) was calculated by correlating the rs-fMRI time courses between each voxel and the striatal seeds (i.e. spherical regions placed at the striatums). The level of TNF-α in serum was evaluated by Milliplex assay. Factorial analysis was performed to assess the interaction effects of ‘TNF-α × treatment’ in the regions with between-group FC difference.
Results
Compared with controls, MDD patients showed significantly higher striatal FC in the medial prefrontal cortex (MPFC) and bilateral middle/superior temporal cortices before SSRI treatment (p < 0.001, uncorrected). Moreover, a significant interaction effect of ‘TNF-α × treatment’ was found in MPFC-striatum FC in MDD patients (p = 0.002), and the significance remained after adjusted for age, gender, head motion, and episode of disease.
Conclusion
These findings provide evidence that treatment-related brain connectivity change is dependent on the TNF-α level in MDD patients, and the MPFC-striatum connectivities possibly serve as an important target in the brain.
Van der Waals (vdW) heterojunctions consisting of vertically-stacked individual or multiple layers of two-dimensional layered semiconductors, especially the transition metal dichalcogenides (TMDs), show novel optoelectronic functionalities due to the sensitivity of their electronic and optical properties to strong quantum confinement and interfacial interactions. Here, monolayers of n-type MoSe2 and p-type Mo1−xWxSe2 are grown by vapor transport methods, then transferred and stamped to form artificial vdW heterostructures with strong interlayer coupling as proven in photoluminescence and low-frequency Raman spectroscopy measurements. Remarkably, the heterojunctions exhibit an unprecedented photoconductivity effect that persists at room temperature for several days. This persistent photoconductivity is shown to be tunable by applying a gate bias that equilibrates the charge distribution. These measurements indicate that such ultrathin vdW heterojunctions can function as rewritable optoelectronic switches or memory elements under time-dependent photo-illumination, an effect which appears promising for new monolayer TMDs-based optoelectronic devices applications.
Objective: To study the relationship of Nε-(carboxymethyl)-lysine level (CML)
with microstructure changes of white matter (WM), and cognitive impairment
in patients with type 2 diabetes mellitus (T2DM) and to discuss the
potential mechanism underlying T2DM-associated cognitive impairment. Methods: The study was performed in T2DM patients (n=22) with disease course
≥5 years and age ranging from 65 to 75 years old. A control group consisted
of 25 sex- and age-matched healthy volunteers. Fractional anisotropy (FA) of
several WM regions was analyzed by diffusion tensor imaging scan. Plasma CML
levels were measured by enzyme-linked immunosorbent assay, and cognitive
function was assessed by Mini-Mental State Examination and Montreal
cognitive assessment (MoCA). Results: The total Mini-Mental State Examination score in the patient group
(25.72±3.13) was significantly lower than the control group (28.16±2.45)
(p<0.05). In addition, the total MoCA score in the patient group
(22.15±3.56) was significantly lower than the control group 25.63±4.12)
(p<0.01). In the patient group, FA values were significantly decreased in
the corpus callosum, cingulate fasciculus, inferior fronto-occipital
fasciculus, parietal WM, hippocampus, and temporal lobes relative to
corresponding regions of healthy controls (p<0.05). Plasma CML level was
negatively correlated with average FA values in the global brain (r=−0.58,
p<0.01) and MoCA scores (r=−0.47, p<0.05). Conclusions: In T2DM, WM microstructure changes occur in older patients, and
elevations in CML may play a role in the development of cognitive
impairment.
Depression among older adults is under-recognized either in the community or in general hospitals in Chinese culture. This study aimed to develop a culturally appropriate screening instrument for late-life depression in the non-psychiatric settings and to test its reliability and validity for a diagnosis of depression.
Methods:
Using a Delphi method, we developed a geriatric depression inventory (GDI), consisting of 12 core symptoms of depressive disorder in old age. We investigated its reliability and validity on 89 patients with late-life depression and 249 non-depression controls. Both self-report (GDI-SR) and physician-interview (GDI-RI) versions were assessed.
Results:
Cronbach's α coefficient was 0.843 for GDI-SR and 0.880 for GDI-RI. Both GDI-SR and GDI-RI showed good concurrent validity with the 15-item Geriatric Depression Scale (GDS-15) (GDI-SR: r = 0.750, p < 0.001; GDI-RI: r = 0.733, p < 0.001). The area under the curve of the receiver operating characteristic (ROC) was 0.938 for GDI-SR and 0.961 for GDI-RI, suggesting good to excellent discrimination of depression versus non-depression. Using a cut-off of three items endorsed, sensitivity and specificity were 92.1% and 81.9% for GDI-SR, and 93.3% and 87.1% for GDI-RI.
Conclusions:
The GDI, either based on self-report or rater interview, is a reliable and valid instrument for the detection of depression among older adults in non-psychiatric medical settings in Chinese culture.
Potatoes are usually a high-glycaemic index (GI) food. Finding a low-GI potato and developing a screening method for finding low-GI cultivars are both health and agricultural priorities. The aims of the present study were to screen the commonly used and newly introduced cultivars of potatoes, in a bid to discover a low-GI potato, and to describe the relationship between in vitro starch digestibility of cooked potatoes and their in vivo glycaemic response. According to International Standard Organisation (ISO) guidelines, seven different potato cultivars were tested for their GI. In vitro enzymatic starch hydrolysis and chemical analyses, including amylose content analysis, were carried out for each potato cultivar, and correlations with the respective GI values were sought. The potato cultivars had a wide range of GI values (53–103). The Carisma cultivar was classified as low GI and the Nicola cultivar (GI = 69) as medium GI and the other five cultivars were classified as high GI according to ISO guidelines. The GI values were strongly and positively correlated with the percentage of in vitro enzymatic hydrolysis of starch in the cooked potatoes, particularly with the hydrolysis percentage at 120 min (r 0·91 and P <0·01). Amylose, dietary fibre and total starch content was not correlated with either in vitro starch digestibility or GI. The findings suggest that low-GI potato cultivars can be identified by screening using a high-throughput in vitro digestion procedure, while chemical composition, including amylose and fibre content, is not indicative.
The driving mechanism of solar flares and coronal mass ejections is a topic of ongoing debate, apart from the consensus that magnetic reconnection plays a key role during the impulsive process. While present solar research mostly depends on observations and theoretical models, laboratory experiments based on high-energy density facilities provide the third method for quantitatively comparing astrophysical observations and models with data achieved in experimental settings. In this article, we show laboratory modeling of solar flares and coronal mass ejections by constructing the magnetic reconnection system with two mutually approaching laser-produced plasmas circumfused of self-generated megagauss magnetic fields. Due to the Euler similarity between the laboratory and solar plasma systems, the present experiments demonstrate the morphological reproduction of flares and coronal mass ejections in solar observations in a scaled sense, and confirm the theory and model predictions about the current-sheet-born anomalous plasmoid as the initial stage of coronal mass ejections, and the behavior of moving-away plasmoid stretching the primary reconnected field lines into a secondary current sheet conjoined with two bright ridges identified as solar flares.
Silver nanoparticles (AgNPs) in silicate clay matrix films were fabricated from solution casting method. The Ag/clay dispersion was first prepared from in situ reduction of silver nitrate in the presence of silicate clay platelets and ethanol as the reducing agent. The morphologies of AgNPs have changed in a hierarchical manner, from sphere to cube and then to rod and wire morphologies during the annealing at 200 °C. The originally homogeneous AgNPs distribution in the clay matrix underwent the transformation of AgNPs in moving to the film surface and coalescing to larger sizes. The hierarchical change continued to form other morphologies. We observed the self-assembled morphologies including spherical (diameter ∼ 50 nm), cubic (length ∼100 nm), rod-like (length ∼ 1.6 μm and width ∼300 nm) and then to lengthy wire Ag (length ∼10μm). The kinetic mobility of AgNPs to surface and the characterization of Ag composition were confirmed through energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD).
In situ investigation of the interfacial reaction in the Sn/Cu thin film during aging, and reflow was carried out by synchrotron radiation with high intensity and high resolution of x-ray. With this technique, the phase transformation and evolution of the Sn/Cu thin film during heat treatment can be directly and continuously investigated. Moreover, the information for coefficient of thermal expansion in intermetallic compounds was also evaluated by this approach.
Ferroelectric random access memory (FeRAM) is believed to be the most promising candidate for the next generation non-volatile memory due to its fast access time and low power consumption. Fabrication technologies of FeRAM can be divided into two parts: CMOS technologies for circuits which are standard and can be shared with traditional IC process line, and process relating to ferroelectric which is separated with CMOS process and defined as backend module. This paper described technologies for integrating ferroelectric capacitors into standard CMOS, mainly about modeling of ferroelectric capacitors and backend fabrication technologies. Hysteresis loop of the ferroelectric capacitor is the basis for FeRAM to store data. Models to describe this characteristic are the key for the design of FeRAM. A transient behavioral ferroelectric capacitor model based on C-V relation for circuit simulation is developed. The arc tangent function is used to describe the hysteresis loop. “Negative capacitance” phenomenon at reversing points of applied voltage is analyzed and introduced to the model to describe transient behaviors of the capacitor. Compact equivalent circuits are introduced to integrate this model into HSPICE for circuit simulation. Ferroelectric materials fabrication, electrodes integration and etching are the main technologies of FeRAM fabrication process. An metal organic chemical vapor deposition (MOCVD) process is developed to fabricate high quality Pb(Zr1-xTix)O3 (PZT) films. Pt is known to cause the fatigue problems when used as electrodes with PZT. Ir is used as electrodes to improve the fatigue property of PZT based capacitors, and mechanism of the fatigue is analyzed. Hard mask is used to reduce the size of the capacitors and damage caused in etching process. In our process, Al2O3 is developed as hard mask, which simplifies the FeRAM backend integration process.
Ferromagnetic delta-phase manganese gallium with Mn:Ga ratio between 1:1 to 1.5:1 is grown on wurtzite gallium nitride and scandium nitride substrates, using molecular beam epitaxy. The dependencies of growth properties, e.g. interface formation, surface reconstruction and crystalline quality, on substrate crystallographic structure and polarity are investigated. Results suggest that for growth on wurtzite GaN, Ga-polar surface promotes quicker interface formation, and also results in better crystalline quality of the MnGa film, as compared to N-polar. The crystal orientation and magnetic anisotropy are found to be different than those grown on cubic scandium nitride substrates.
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