Volatile phenols exist in wine and can be markers for Brettanomyces and smoke taint off-odors. Cyclodextrins (CDs) are found to be capable of forming inclusion complexes with volatile phenols. Cross peaks on 2D 1H ROESY nuclear magnetic resonance (NMR) spectra demonstrated inclusion of volatile phenols in the β-CD cavity, while difference tests confirmed this resulted in a perceptible reduction of their sensory impact. However, a conventional headspace solid phase microextraction (HS-SPME) method using an isotopically labelled normalizing standard failed to quantify the residual volatile phenols by gas chromatography-mass spectrometry (GC-MS) because of inclusion of the standard by the CDs. A new method involving an additional liquid phase was developed and validated for quantitation of volatile phenols in the presence of CDs. The retention of eight volatile phenols by α-, β-, and γ-CD was subsequently studied.
Abstract Ionic conductive hydrogels as promising materials have become focus of artificial soft tissue or soft stretchable electronic devices. Especially, the next‐generation flexible electronics greatly require achieving multifunction simultaneously. Herein, a transparent hydrogel with high mechanical properties (1.73 MPa for mechanical stress, 630% for mechanical strain) and excellent ionic conductivity is fabricated based on a fully physical cross‐linked network. The stiff long polyvinyl alcohol (PVA) chains as a skeleton to form a “hard” network and the short polyacrylic acid (PAA) chains regard as the “soft” network. Moreover, the biomaterial β‐cyclodextrin (β‐CD) as physical cross‐linkers is used in the “hard–soft” hybrid networks. The construction of “soft and hard” structure is successful to integrate the good transparency, remarkable mechanical properties, and outstanding sensitivity (strain, pressure, pH, and organic solvent) together for assembling multiple sensors, which hold a promising practical development value in the domain of soft wearable electronics and sensing materials in the future.
Background. Neuroimaging biomarkers are valuable predictors of motor improvement after stroke, but there is a gap between published evidence and clinical usage. Objective. In this work, we aimed to investigate whether machine learning techniques, when applied to a combination of baseline whole brain volumes and clinical data, can accurately predict individual motor outcome after stroke. Methods. Upper extremity Fugl-Meyer Assessments (FMA-UE) were conducted 1 week and 12 weeks, and structural MRI was performed 1 week, after onset in 56 patients with subcortical infarction. Proportional recovery model residuals were employed to assign patients to proportional and poor recovery groups (34 vs 22). A sophisticated machine learning scheme, consisting of conditional infomax feature extraction, synthetic minority over-sampling technique for nominal and continuous, and bagging classification, was employed to predict motor outcomes, with the input features being a combination of baseline whole brain volumes and clinical data (FMA-UE scores). Results. The proposed machine learning scheme yielded an overall balanced accuracy of 87.71% in predicting proportional vs poor recovery outcomes, a sensitivity of 93.77% in correctly identifying poor recovery outcomes, and a ROC AUC of 89.74%. Compared with only using clinical data, adding whole brain volumes can significantly improve the classification performance, especially in terms of the overall balanced accuracy (from 80.88% to 87.71%) and the sensitivity (from 92.23% to 93.77%). Conclusions. Experimental results suggest that a combination of baseline whole brain volumes and clinical data, when equipped with appropriate machine learning techniques, may provide valuable information for personalized rehabilitation planning after subcortical infarction.
Exploitation of the biodiversity of native wine yeast is a means of modifying the sensory characteristics of wine. Samples from different regions in China were analysed to screen native isolates as potential starter cultures. Through morphological and molecular biological analyses, we found six species, belonging to four genera (Hanseniaspora, Saccharomyces, Rhodotorula and Metschnikowia). These species were subjected to stress tolerance assays (ethanol, glucose, SO2 and pH), enzymatic activity tests (sulphite reductase activity, β-glucosidase activity and protease activity) and fermentation tests. Saccharomyces cerevisiae showed a high tolerance to ethanol and completed fermentation independently. Hanseniaspora demonstrated good enzymatic activity and completed sequential fermentation. The fermentation experiment showed that the PCT4 strain had the best aroma complexity. This study provides a reference for selecting new starters from the perspective of flavour enzymes and tolerance and diversifying the sensory quality of wines from the region.
Viscous debris flows are saturated with loose earth on slopes or on gully beds,which are rich in clay and have a bulk density of 1.8-1.9 t/m~3 and the static shear stress of 30Pa.The yield of viscous debris flows consists of two successive processes: displacement of totally or partially saturated earth by infiltrated water,and successive liquidization.Four types of ideal displacement processes and relevant four types of liqudization processes for viscous debris flow yield are firstly introducted in this paper,and then based on actual conditions of debris flow activities,four types of common processes for viscous debris flow yield are proposed for comprehensive approaches to the mechanism of viscous debris flow yield.
Cerebral infarction causes secondary neurodegeneration and angiogenesis in thalamus, which impacts functional recovery after stroke. Here, we hypothesize that activation of ephrinB2 could stimulate angiogenesis and restore the secondary neurodegeneration in thalamus after cerebral infarction. Focal cerebral infarction was induced by middle cerebral artery occlusion (MCAO). Secondary damage, angiogenesis, amyloid-β (Aβ) deposits, levels of ephrinB2 and receptor for advanced glycation end product (RAGE) in the ipsilateral thalamus were determined by immunofluorescence and immunoblot. The contribution of ephrinB2 to angiogenesis was determined by siRNA-mediated knockdown of ephrinB2 and pharmacological activation of ephrinB2. The results showed that formation of new vessels and ephrinB2 expression was markedly increased in the ipsilateral thalamus at seven days after MCAO. EphrinB2 knockdown markedly suppressed angiogenesis coinciding with increased Aβ accumulation, neuronal loss and gliosis in the ipsilateral thalamus. In contrast, clustered EphB2-Fc significantly enhanced angiogenesis, alleviated Aβ accumulation and the secondary thalamic damage, which was accompanied by accelerated function recovery. Additionally, activation of ephrinB2 significantly reduced RAGE levels in the ipsilateral thalamus. Our findings suggest that activation of ephrinB2 promotes angiogenesis, ameliorates Aβ accumulation and the secondary thalamic damage after cerebral infarction. Additionally, RAGE might be involved in Aβ clearance by activating ephrinB2 in the thalamus.
Abstract Crab chitin was sulfated under heterogeneous conditions using sulfamic acid in N'N-dimethylformamide to selectively sulfate the microfibril surface. The degree of sulfation followed a first order kinetics assuming a limited available reaction sites on the surface, and leveled off at a bulk degree-of-substitution of 0.4, corresponding to 2 mol/kg of sulfate groups. The reaction rate was proportional to the square of sulfamic acid concentration, suggesting involvement of two sulfamic acid molecules in a reaction. When washed with water after sulfation, the crab shell chitin fragments swelled anisotropically in the helicoidal axis direction, revealing regular alternating birefringence under optical microscope. Further mechanical treatment with high-pressure homogenizer lead to slender nanofibrils, whose diameters were of the order of 6 nm according to turbidimetric analysis, in agreement with the Scherrer size estimated from X-ray diffraction line broadening. Both AFM and TEM measurement showed presence of further smaller fragments with diameter of 3-4 nm and length of ~300 nm. The current approach presents a rapid and efficient modification to chitin, and a strategy for the preparation of stable nanochitins suspension.
Accumulating evidence indicates that dynamic amplitude of low-frequency fluctuations (dALFF) or dynamic functional connectivity (dFC) can provide complementary information, distinct from static amplitude of low-frequency fluctuations (sALFF) or static functional connectivity (sFC), in detecting brain functional abnormalities in brain diseases. We aimed to examine whether dALFF and dFC can offer valuable information for the detection of functional brain abnormalities in patients with blepharospasm.We collected resting-state functional magnetic resonance imaging data from 46 patients each of blepharospasm, hemifacial spasm (HFS), and healthy controls (HCs). We examined intergroup differences in sALFF and dALFF to investigate abnormal regional brain activity in patients with blepharospasm. Based on the dALFF results, we conducted seed-based sFC and dFC analyses to identify static and dynamic connectivity changes in brain networks centered on areas showing abnormal temporal variability of local brain activity in patients with blepharospasm.Compared with HCs, patients with blepharospasm displayed different brain functional change patterns characterized by increased sALFF in the left primary motor cortex (PMC) but increased dALFF variance in the right PMC. However, differences were not found between patients with HFS and HCs. Additionally, patients with blepharospasm exhibited decreased dFC strength, but no change in sFC, between right PMC and ipsilateral cerebellum compared with HCs; these findings were replicated when patients with blepharospasm were compared to those with HFS.Our findings highlight that dALFF and dFC are complementary to sALFF and sFC and can provide valuable information for detecting brain functional abnormalities in blepharospasm. Blepharospasm may be a network disorder involving the cortico-ponto-cerebello-thalamo-cortical circuit.
Agomelatine is effective in the treatment of depression, but its effect for post-stroke depression (PSD) remains unclear. This study was conducted to compare the efficacy and safety of agomelatine versus SSRIs/SNRIs in treating PSD. We systematically searched Embase, PubMed, Cochrane Library, WanFang Data, China National Knowledge Infrastructure, and Cqvip databases for double-blind randomized controlled studies comparing the efficacy and safety of agomelatine versus SSRIs/SNRIs for PSD until December 2022. The primary efficacy endpoint was the Hamilton Depression Rating Scale (HAMD) score, and the primary safety endpoint was the incidence of overall adverse reactions. Nine studies comprising 857 patients with PSD were included. After 6-12 weeks of treatment, the HAMD score ( P = 0.16) and the overall response rates ( P = 0.20) in the agomelatine group were comparable to that in the SSRIs/SNRIs group. Participants treated with agomelatine achieved higher Barthel Index scores compared with the SSRIs/SNRIs group ( P = 0.02). There was a significantly lower incidence of overall adverse reactions ( P = 0.008) and neurological adverse reactions ( P < 0.0001) in the agomelatine group. The efficacy of agomelatine for treating PSD is probably comparable to that of SSRIs/SNRIs, and it may improve stroke outcomes with better safety.