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Hot air drying is widely adopted to extend the shelf life of Pleurotus eryngii, which is an edible fungus with high nutritional value and large market demand. Understanding moisture transfer during hot air drying is essential for both quality improvement and energy-efficient dryer design. In this study, we investigated the drying kinetics of P. eryngii slices with different thicknesses (4, 8, and 12 mm) under different hot air temperature levels (40, 50, 60, 70, and 80°C) and a constant air velocity (2 m/s). It is found that the drying rate increases with the increase of the hot air temperature or the decrease of the thickness of P. eryngii slices. Only a falling rate period was observed during the hot air drying. We used eight mathematical models to describe the drying kinetics of P. eryngii slices and found that the logarithmic model fits the experimental data best. The fitted effective moisture diffusivity of P. eryngii slices is in the range of 3.34 × 10 − 9 3.34\times {10}^{-9} to 2.25 × 10 − 9 m 2 / s 2.25\times {10}^{-9}{\text{ m}}^{2}/\text{s} , and the fitted drying activation energy is 19.30 kJ/mol, agreeing with the results in the literature. Additionally, we noticed that the color of dried P. eryngii slices becomes darker with the increase of hot air temperature due to the Maillard browning reaction. This study helps to understand the drying kinetics of P. eryngii slices during the hot air drying and guides the drying process optimization.

Hollow fiber-based porous structures (HFPSs) demonstrate promising potentials in thermal insulations. However, the thermal transport in HFPSs was not explored yet. Herein, we developed a unit cell model to explore the effect of both geometric and thermophysical parameters on the effective thermal conductivity of HFPSs. The predictions from the developed model agree with the experimental data in the literature. The modeling results show that decreasing external hollow fiber diameter, shell thickness, the thermal conductivity of solid backbone, and gas pressure can reduce the effective thermal conductivity of the HFPSs. The effective thermal conductivity of the HFPSs trends to that of stationary air (0.026 W/(m⋅K), 300 K, 1.0 atm) as porosity increases. Reducing the pore size to nanometer-scale or decreasing the gas pressure is the most effective way to achieve a thermal conductivity below that of stationary air. This work guides the structural design and optimization of HFPSs as lightweight super-thermal insulating materials.

Nanoporous insulating materials are of importance for applications such as energy-efficient buildings, energy storage and savings, and cryogenic engineering. Recent progress on manufacturing technology has enabled the fabrication of ordered nanostructures to be practical, providing a possibility to fabricate high-performance insulation materials. In this work, three kinds of nanoporous insulating materials with regular geometric structures and controllable thermal conductivities, including a simple cubic packing, a face-centered cubic packing, and a cubic array of intersecting spheres packing of uniform-sized hollow nanospheres, were designed. The effective thermal conductivity models of each packing structure were developed according to the assumption of one-dimensional heat transfer, in which the following factors including material types, size of the hollow nanosphere packing structure (e.g., sphere size, spherical shell thickness, contact ratio), gas pressure, the rarefaction effect of gas and the mean free path of phonons were considered. The developed models of the hollow nanosphere packing structures were validated by the experimental results from the literature. It is found that the effective thermal conductivity can be lowered to ~ 0.01 W/(m⋅K) by tuning the packing style and size of hollow nanosphere packing structures in the room environment, showing excellent thermal insulation performance. The work provides a new strategy for the design of super-insulation materials.

Silica aerogel has attracted great interest in thermal insulation applications due to its ultralow thermal conductivity. However, silica aerogel is transparent to the infrared radiation in the range of 3-8 µm, making them be not suitable for high temperature thermal insulation applications. Here, we developed an optimization method considering both thermal radiation and heat conduction to design the geometric structures of aerogel composites with minimized thermal conductivity. The results show that when the ambient temperature is lower than ~ 600 K, the additives with low thermal conductivity are preferred. When the ambient temperature is higher than ~ 600 K, the additives with high extinction coefficients are needed. The additives with a broad size distribution could enable the aerogel composites to have an optimal thermal insulation performance in the environment with a changing temperature. The work provides a guideline for the geometric design of aerogel composites for high temperature thermal insulation applications.

Macrophage apoptosis is a host innate defense mechanism against tuberculosis (TB).In this study, we aimed to investigate the role of microRNA-223 (miR-223) in macrophage apoptosis of TB.We analyzed apoptosis in peripheral blood macrophages of active TB patients, infected human macrophages (TDMs and MDMs) with the Mycobacterium tuberculosis (Mtb) strain H37Rv, and observed the expression of miR-223 to investigate the relationship between miR-223 and macrophage apoptosis induced by Mtb.The apoptosis rate of peripheral blood macrophages decreased in active TB patients compared with healthy controls, and miR-223 expression increased significantly in macrophages after H37Rv infection. Transfection of human macrophages (TDMs and MDMs) with miR-223 inhibited macrophage apoptosis. We also demonstrated that miR-223 directly suppressed forkhead box O3 (FOXO3), and FOXO3 played a critical role as a mediator of the biological effects of miR-223 in macrophage apoptosis. The overexpression of FOXO3 remarkably reversed the apoptosis inhibitory effect of miR-223.Our data provide new clues for the essential role of miR-223 in the regulation of anti-Mtb-directed immune responses, which relies on the regulation of FOXO3 expression.

As a major health threat, tuberculosis (TB) is resistant against the current therapeutic strategies. Increasing evidence indicates that miRNAs are implicated in various disorders by affecting specific target genes. Recently, the association of miRNAs with TB has also been established by several studies, and their potentials in the prognosis and treatment of TB have also been verified. miR-183 is shown to promote the activation of macrophage through NF-κB pathway. However, it is still unclear if serum miR-183 can be used to assess the activity of TB-associated macrophage. This study was aimed to address this issue. We employed qPCR assay to detect the expression level of miR-183 in blood from TB patients and healthy individuals. miR-183 abundance was found to be increased in serum samples from TB patients, compared with healthy controls. Further analysis revealed that miR-183 level is positively associated with the activity of macrophages from TB patients, evidenced by their increased phagocytosis rates and enzyme activity in high serum miR-183 group. In conclusions, high level of serum miR-183 is associated with the activity of macrophage originating from TB patients.

The aim of the present study was to investigate the association between microRNA (miR)-155 and apoptosis of monocytes infected by Mycobacterium tuberculosis, to examine the effect of forkhead box O3 (FOXO3) on miR‑155. The present study analysed the apoptosis of CD14+ in the peripheral blood of patients with active tuberculosis, disposed the THP‑1 human monocytic cell line by BCG and examined the expression of miR‑155. Furthermore, the expression of FOXO3 in THP‑1 cells was determined, and wild- and mutant-type luciferase reporter plasmids containing FOXO3 3'‑untranslated regions (UTRs) were constructed to analyse the expression of luciferase. Finally, an over‑expression plasmid was constructed, and THP-1 cells were transfected with control miRNA, miR‑155 and the plasmid, which revealed that miR‑155 inhibited the apoptosis of THP‑1 cells. miR‑155 in the THP‑1 cells infected by BCG was upregulated and apoptosis also increased. However, the apoptosis declined when the cells were transfected with the control miRNA and miR‑155. Folllowing transfection with miR‑155, the expression of FOXO3 decreased. Transfection with miR‑155 and the FOXO3 3'-UTRs significantly reduced luciferase, and overexpression of FOXO3 reversed the inhibitory role of miR‑155. From these results, it was concluded that mycobacteria can improve the level of miR‑155, while BCG can induce apoptosis in THP‑1 cells. The results suggested FOXO3 is a downstream target gene of miR‑155, which combines 3'-UTRs to inhibit the expression of FOXO3.

Tuberculosis (TB) is still an infectious disease that greatly threatens human health, and is always refractory to the current therapeutic modalities. Accumulated evidence revealed that microRNAs (miRNAs) are closely with various pathologies, such as TB. The possibilities of miRNAs as diagnostic biomarkers and therapeutic targets have been proved. However, it is still unknown if miRNA is implicated in the TB-associated immunity. This study revealed that miR-155, which has been shown to suppress the activation of natural killer (NK) cells associated with tumors, was downregulated in serum samples of TB patients (n=90), compared with healthy controls (n=31). Cytotoxicity assays indicated that NK cells, which have been demonstrated to promote TB progression, exhibited lower cytotoxicity in high serum miR-155 TB patients (n=37). There is an inverse relationship between serum miR-155 abundance and NK cell cytotoxicity (R=-0.659, P=0.000). Further studies demonstrated that miR-155 level is inversely associated with the concentration of TNFα secreted by NK cells from TB patients (n=37, R=-0.694, P=0.000). Collectively, serum miR-155 level was shown to be negatively associated with the TB-suppressing activity of NK cells, and this miRNA can be used as a potential therapeutic agent for TB treatment.

Objective: To evaluate multiplex allele specific polymerase chain reaction as a rapid molecular tool for detecting multidrug-resistant tuberculosis. Methods: Based on drug susceptibility testing, 103 isolates were multidrug-resistant tuberculosis and 45 isolates were sensitive to isonicotinylhydrazine and rifampin. Primers were designed to target five mutations hotspots that confer resistance to the first-line drugs isoniazid and rifampin, and multiplex allele specific polymerase chain reaction was performed. Whole-genome sequencing confirmed drug resistance mutations identified by multiplex allele specific polymerase chain reaction. Results: DNA sequencing revealed that 68.9% of multidrug-resistant strains have point mutations at codon 315 of the katG gene, 19.8% within the mabA-inhA promoter, and 98.0% at three hotspots within rpoB. Multiplex allele specific polymerase chain reaction detected each of these five mutations, yielding 82.3% sensitivity and 100% specificity for isoniazid resistance, and 97.9% sensitivity and 100% specificity for rifampin resistance as compared to drug susceptibility testing. Conclusions: The results show that multiplex allele specific polymerase chain reaction is an inexpensive and practical method for rapid detection of multidrug-resistant tuberculosis in developing countries. Keywords: Mycobacterium tuberculosis, Multiplex allele specific polymerase chain reaction (MAS-PCR)