24 research outputs found
Packaged Droplet Microresonator for Thermal Sensing with High Sensitivity
Liquid droplet and quasi-droplet whispering gallery mode (WGM) microcavities have been widely studied recently for the enhanced spatial overlap between the liquid and WGM field, especially in sensing applications. However, the fragile cavity structure and the evaporation of liquid limit its practical applications. Here, stable, packaged, quasi-droplet and droplet microcavities are proposed and fabricated for thermal sensing with high sensitivity. The sensitivity and electromagnetic field intensity distribution are analyzed by Mie theory, and a quantified definition of the quasi-droplet is presented for the first time to the best of our knowledge. By doping dye material directly into the liquid, lasing packaged droplet and quasi-droplet microcavity sensors with a high thermal sensitivity of up to 205.3 pm/°C are experimentally demonstrated. The high sensitivity, facile fabrication, and mechanically robust properties of the optofluidic, packaged droplet microresonator make it a promising candidate for future integrated photonic devices
Identification markers of goat milk adulterated with bovine milk based on proteomics and metabolomics
This study investigated the differences in proteins and metabolites from goat and bovine milk, and their mixtures, using data-independent-acquisition-based proteomics and metabolomics methods. In the skim milk, relative abundances of secretoglobin family 1D member (SCGB1D), polymeric immunoglobulin receptor, and glycosylation-dependent cell adhesion molecule 1 were increased, with an increase in the amount of 1–100 % bovine milk and served as markers at the 1 % adulteration level. In whey samples, β-lactoglobulin and α-2-HS-glycoprotein could be used to detect adulteration at the 0.1 % adulteration level, and SCGB1D and zinc-alpha-2-glycoprotein at the 1 % level. The metabolites of uric acid and N-formylkynurenine could be used to detect bovine milk at adulteration levels as low as 1 % based on variable importance at a projection value of > 1.0 and P-value of < 0.05. Our findings suggest novel markers of SCGB1D, uric acid, and N-formylkynurenine that can help to facilitate assessments of goat milk authenticity
Research Progress of Microbiota-Gut-Brain Axis in Parkinson's Disease
Parkinson’s disease (PD) is a common neurodegenerative disorder characterized by misfolding of α-synuclein. Clinical manifestations include slowly developing resting tremor, muscle rigidity, bradykinesia and abnormal gait. The pathological mechanisms underlying PD are complex and yet to be fully elucidated. Clinical studies suggest that the onset of gastrointestinal symptoms may precede motor symptoms in PD patients. The microbiota-gut-brain axis plays a bidirectional communication role between the enteric nervous system and the central nervous system. This bidirectional communication between the brain and gut is influenced by the neural, immune and endocrine systems related to the gut microbiome. A growing body of evidence indicates a strong link between dysregulation of the gut microbiota and PD. In this review, we present recent progress in understanding the relationship between the microbiota-gut-brain axis and PD. We focus on the role of the gut microbiota, the unique changes observed in the microbiome of PD patients, and the impact of these changes on the progression of PD. Finally, we evaluate the role of current treatment strategies for PD, including probiotics, fecal microbial transplants, dietary modifications, and related drug therapies
Associations of Triglycerides and Atherogenic Index of Plasma with Brain Structure in the Middle-Aged and Elderly Adults
Triglyceride (TG) and atherogenic index of plasma (AIP) have been acknowledged to be risk factors for vascular insults, but their impacts on the brain system remain elusive. To fill in some gaps, we investigated associations of TG and AIP with brain structure, leveraging the UK Biobank database. TG and high-density lipoprotein cholesterol (HDL-C) were examined at baseline and AIP was calculated as log (TG/HDL-C). We build several linear regression models to estimate associations of TG and AIP with volumes of brain grey matter phenotypes. Significant inverse associations of TG and AIP with volumes of specific subcortical traits were observed, among which TG and AIP were most significantly associated with caudate nucleus (TG: β [95% confidence interval CI] = −0.036 [−0.051, −0.022], AIP: −0.038 [−0.053, −0.023]), thalamus (−0.029 [−0.042, −0.017], −0.032 [−0.045, −0.019]). Higher TG and AIP were also considerably related with reduced cortical structure volumes, where two most significant associations of TG and AIP were with insula (TG: −0.035 [−0.048, −0.022], AIP: −0.038 [−0.052, −0.025]), superior temporal gyrus (−0.030 [−0.043, −0.017], −0.033 [−0.047, −0.020]). Modification effects of sex and regular physical activity on the associations were discovered as well. Our findings show adverse associations of TG and AIP with grey matter volumes, which has essential public health implications for early prevention in neurodegenerative diseases
Fenofibrate improves vascular endothelial function and contractility in diabetic mice
Fenofibrate, a peroxisome proliferator-activated receptors α (PPARα) agonist, reduces vascular complications of diabetic patients but its protective mechanisms are not fully understood. Here we tested the hypothesis that fenofibrate improves vascular endothelial dysfunction by balancing endothelium-dependent relaxation and contractility of the aorta in diabetes mellitus (DM). In streptozotocin-induced diabetic mice, eight weeks of fenofibrate treatment (100 mg/Kg/d) improved endothelium dependent relaxation in the macro- and microvessels, increased nitric oxide (NO) levels, reduced renal damage markers and effects of the vasoconstrictor prostaglandin. Levels of superoxide dismutase and catalase were both reduced and hydrogen peroxide was increased in vehicle-treated DM, but these changes were reversed by fenofibrate treatment. Vasodilation of the aorta after fenofibrate treatment was reversed by PPARα or AMPKα inhibitors. Western blots showed that fenofibrate treatment elevated PPARα expression, induced liver kinase B1 (LKB1) translocation from the nucleus to the cytoplasm and activated AMP-activated protein kinase-α (AMPKα), thus activating endothelial NO synthase (eNOS). Also, fenofibrate treatment decreased NF-κB p65 and cyclooxygenase 2 proteins in aortas. Finally, incubation with indomethacin in vitro improved aortic contractility in diabetic mice. Overall, our results show that fenofibrate treatment in diabetic mice normalizes endothelial function by balancing vascular reactivity via increasing NO production and suppressing the vasoconstrictor prostaglandin, suggesting mechanism of action of fenofibrate in mediating diabetic vascular complications. Keywords: Diabetes, Fenofibrate, Endothelial dysfunction, Nitric oxide, Oxidative stres
Phonon-Assisted Ultrafast Charge Transfer at van der Waals Heterostructure Interface
The van der Waals (vdW) interfaces
of two-dimensional (2D) semiconductor
are central to new device concepts and emerging technologies in light-electricity
transduction where the efficient charge separation is a key factor.
Contrary to general expectation, efficient electron–hole separation
can occur in vertically stacked transition-metal dichalcogenide heterostructure
bilayers through ultrafast charge transfer between the neighboring
layers despite their weak vdW bonding. In this report, we show by <i>ab initio</i> nonadiabatic molecular dynamics calculations,
that instead of direct tunneling, the ultrafast interlayer hole transfer
is strongly promoted by an adiabatic mechanism through phonon excitation
occurring on 20 fs, which is in good agreement with the experiment.
The atomic level picture of the phonon-assisted ultrafast mechanism
revealed in our study is valuable both for the fundamental understanding
of ultrafast charge carrier dynamics at vdW heterointerfaces as well
as for the design of novel quasi-2D devices for optoelectronic and
photovoltaic applications