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The airway vagal preganglionic neurons (AVPNs) providing projections to intrinsic tracheobronchial ganglia are considered to be crucial to modulation of airway resistance in physiological and pathological states. AVPNs classified into inspiratory-activated AVPNs (IA-AVPNs) and inspiratory-inhibited AVPNs (II-AVPNs) are regulated by thyrotropin-releasing hormone (TRH)-containing terminals. TRH causes a direct excitatory current and attenuates the phasic inspiratory glycinergic inputs in II-AVPNs, however, whether and how TRH influences IA-AVPNs remains unknown. In current study, TRH regulation of IA-AVPNs and its mechanisms involved were investigated. Using retrogradely fluorescent labeling method and electrophysiology techniques to identify IA-AVPNs in brainstem slices with rhythmic inspiratory hypoglossal bursts recorded by a suction electrode, the modulation of TRH was observed with patch-clamp technique. The findings demonstrate that under voltage clamp configuration, TRH (100 nM) caused a slow excitatory inward current, augmented the excitatory synaptic inputs, progressively suppressed the inhibitory synaptic inputs and elicited a distinctive electrical oscillatory pattern (OP). Such a current and an OP was independent of presynaptic inputs. Carbenoxolone (100 μM), a widely used gap junction inhibitor, fully suppressed the OP with persistence of TRH-induced excitatory slow inward current and augment of the excitatory synaptic inputs. Both tetrodotoxin (1 μM) and riluzole (20 μM) functioned to block the majority of the slow excitatory inward current and prevent the OP, respectively. Under current clamp recording, TRH caused a slowly developing depolarization and continuously progressive oscillatory firing pattern sensitive to TTX. TRH increased the firing frequency in response to injection of a square-wave current. The results suggest that TRH excited IA-AVPNs via the following multiple mechanisms: (1) TRH enhances the excitatory and depresses the inhibitory inputs; (2) TRH induces an excitatory postsynaptic slow inward current; (3) TRH evokes a distinctive OP mediated by gap junction. [ABSTRACT FROM AUTHOR]

Water is one of the leading factors in the sliding geological disasters of rock slope, and the harm of fissure water to slope rock mass more and more becomes one of the hotspot research problems in transportation infrastructure construction in mountainous area. Based on the current research status quo of effect of fissure water on rock mass, the interaction mechanisms of water and rock in stratified rock slope were analyzed by related theories such as rock mass mechanics, fluid mechanics and soil mechanics including softening dissolution, scour hole enlargement and padding effective stress, and the influence of water-rock interaction on slope sliding disasters. Then, the influence of rainfall on the displacement field distribution of slope was analyzed during one year of monitoring a typical,natural slope in the Sichuan-Chongqing region. Observations include surface displacement, deep displacement, water level and rainfall. Finally, a targeted reinforced disposal scheme was proposed that considered the rainfall effect. The results provide reference for the instability theory and treatment measures for a high-risk stratified slope. [ABSTRACT FROM AUTHOR]

While cotton is largely produced for its fibers, the seed and hull byproducts are essential for agricultural economies around the world for their high oil content and wide range of uses. Cottonseed oil is often extracted by solvent extraction, a process that is of increasing concern due to its potential to impact human and ecological health. For this reason, environmentally-benign extraction methods are increasingly being explored. The focus of this work is on aqueous surfactant-based extraction of cottonseed collets taken directly from a conventional solvent-based extraction facility. A propoxylated-ethoxylated extended anionic surfactant was tested for its ability to extract cottonseed oil. Results found that moderate (77%) extraction yields could be achieved by the surfactant given adequate surfactant concentration (0.5% in this case). However, unlike previous work with other oilseeds, the best extractions were achieved at moderate interfacial tensions (0.2-3.0 mN/m); surfactant formulations capable of producing ultralow interfacial tensions led to much lower extraction yields, as did water-only extraction. Similar behavior was also observed for two different conventional surfactants, with decreasing interfacial tension values below 0.1 mN/m leading to decreasing yields for all surfactants tested. [ABSTRACT FROM AUTHOR]

[Display omitted] • The BaSb 2(1−x) Bi 2x O 6 solid solutions possess visible light response at 50% and 75% Bi concentration. • The 50 % Bi doped BaSb 2 O 6 (10 1 ¯ 0) surface exhibits excellent photocatalytic activity at applied potential of 1.23 V towards the OER. • The strong adsorption of H atoms on O-sites of the BaSb 2 O 6 (10 1 ¯ 0), 50 % Bi doped BaSb 2 O 6 (10 1 ¯ 0) and BaBi 2 O 6 (10 1 ¯ 0) surfaces hinders the hydrogen emission reaction. • The Gibbs free energies for H* adsorption on Bi-site of the 50 % Bi doped BaSb 2 O 6 (10 1 ¯ 0) surface is close to zero, signifying the optimal conditions can be achieved. In the past few years, a lot of efforts have been made to develop earth abundant semiconductor based photocatalysts for overall water splitting. In this work, novel BaSb 2(1-x) Bi 2x O 6 (x = 0, 0.25, 0.50 0.75, 1) solid solutions have been investigated by using hybrid density functional theory for the application of photocatalytic water splitting. The electronic structure calculations indicate that BaSb 2(1-x) Bi 2x O 6 solid solutions possess visible light response at 50 % and 75 % Bi concentration, which can efficiently utilize visible light for the photocatalytic applications. In addition, the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) have been studied on BaSb 2 O 6 (10 1 ¯ 0), 50 % Bi doped BaSb 2 O 6 (10 1 ¯ 0) and BaBi 2 O 6 (10 1 ¯ 0) surfaces. It was observed that the 50 % Bi doped BaSb 2 O 6 (10 1 ¯ 0) surface exhibits good photocatalytic activity at applied potential of 1.23 V towards the OER while in case of pure BaSb 2 O 6 (10 1 ¯ 0) and BaBi 2 O 6 (10 1 ¯ 0), the limiting potential for the OER are 2.06 and 3.57 eV, respectively. The activity on O-sites of BaSb 2 O 6 (10 1 ¯ 0), 50 % Bi doped BaSb 2 O 6 (10 1 ¯ 0) and BaBi 2 O 6 (10 1 ¯ 0) surfaces is too high for hydrogen emission reaction. However, the Gibbs free energy of H* on Bi-site of the 50 % Bi doped BaSb 2 O 6 (10 1 ¯ 0) surface is close to zero, signifying the optimal conditions can be achieved. [ABSTRACT FROM AUTHOR]

The branching angle is an important trait for controlling the crown architecture of trees. It is not only under genetic regulation, but is also affected by other factors such as environmental and hormones. It is of great significance to explore the molecular regulation mechanism of poplar branching angle; In this paper, transcriptome sequencing technology was used to generate cDNA libraries from axillary buds of the cultivar 'Zhonglin 2025' (a broad-crown poplar; BC) and Populus × zhaiguanheibaiyang (a narrow-crown poplar; NC). NC is characterized by a smaller branch angle than BC, a narrow crown shape, and rapid growth. At the same time, the transcriptome results were verified by qRT-PCR; The results showed that 193.4 million high-quality pure readings were obtained from the BC and NC cDNA libraries, and 1609 DEGs were detected, of which 822 were upregulated and 787 were downregulated. On the basis of functional annotation of the DEGs with gene ontology terms, 41 genes were associated with hormone synthesis and metabolism, 85 genes were associated with auxin transport, and 101 genes were involved in hormone signal transduction. The expression patterns of 12 DEGs associated with branch angle development were verified by qRTPCR, which revealed that the expression patterns were consistent with the results of transcriptome analysis. Quantification of phytohormone contents in axillary buds of NC and BC revealed that auxin content showed the greatest significant difference between NC and BC; Finally, we constructed a model for the phytohormone regulatory network associated with branching angle. It hopes to provide reference for the study of the molecular mechanism of poplar branching angle. [ABSTRACT FROM AUTHOR]

When water drains from a porous medium, a small quantity of residual water typically remains trapped in the medium. The residual water saturation, $$S_{\mathrm{wr}}$$ , is a measure of the ratio of the volume of residual water to the volume of voids in the porous medium. While conventional multiphase flow concepts suggest that $$S_{\mathrm{wr}}$$ has a single value that is a property of the fluids and medium, significant evidence exists that $$S_{\mathrm{wr}}$$ may actually have a dynamic component, exhibiting different observed values when drainage takes place at different rates. Previous work by the authors used experimental measurements to explore this phenomenon. The work described here further explores the phenomenon through the use of a dynamic pore network model specifically designed to study the effects of changing fluid continuity in porous media resulting from dynamic drainage. The model is based on cylindrical pore throats and volumeless pore bodies. The relatively simple structure of the model makes it well suited to the purposes of the work, in that it provides a mechanism to simulate the effect of fluid continuity on drainage from a spatially random porous medium defined by a minimal number of parameters. Results suggest that the phenomenon may occur as a result of pore-scale preferential flow causing desaturation of the porous medium at the water-wet boundary. Significant sensitivity is observed to both porous medium configuration and resistance to water flow across the water-wet boundary. [ABSTRACT FROM AUTHOR]