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Objective: In order to explore the effect of step-down relative humidity drying strategy on the drying characteristics of agricultural products. Methods: Yam slices were selected as the object. The effects of constant humidity drying （relative humidity 15%, 25%, 35%, 45%） and step-down relative humidity drying （relative humidity 45% in the first stage for different times of 10, 20, 30, 60 min and relative humidity 20% in the second stage） on the drying characteristics of yam slices were studied at 60 ℃; The multi-field coupling model was constructed for the simulation of heat and mass transfer; The rehydration ratio and microstructure of the dried product were also measured. Results: ① During constant humidity drying, the drying rate decreased with the increase of relative humidity; However, the drying time of step-down relative humidity drying （45% relative humidity maintained for 20 min and then decreased to 15%） was 8.3% shorter than that of constant humidity drying （relative humidity 15%）. ② The drying rate of yam slices generally increased first and then decreased, The fitting results of drying model showed that it was accurate to describe the changing process of moisture and mass transfer. ③ The rehydration ratio increased first and then decreased with the increase of relative humidity; Under special drying condition of step-down relative humidity drying strategy （relative humidity 45% kept for 20 min and then decreased to 15%）, the yam slices showed honeycomb porous structure, which was good for the mass transfer. Under this condition, the maximum rehydration ratio was 6.85 ± 0.05; Under the drying condition of constant humidity strategy （relative humidity is 20%）, the microstructure of yam sllices begin to shrink and collapse, which led to a lower rehydration rate. Conclusion: During the process of hot air drying, the multi-field coupling model can significantly shorten the drying time, effectively improve the microstructure of materials and improve the rehydration rate of products; The multi-field coupling model can precisely simulate the heat and mass transfer process in yam slices during hot air drying; The research results can provide theoretical basis and technical support for the application and optimization of step-down relative humidity drying strategy.

Proteinaceous matter (PrM) is a substantial component of bioaerosols. Although numerous studies have examined the characteristics and sources of PrM in the atmosphere, its interactions with atmospheric oxidants remain uncertain. A 1‐year observation of PrM characteristics in PM2.5 was performed in both urban Nanchang (eastern China) and suburban Guiyang (southwestern China), respectively. Glycine was the dominant free amino acid (FAA) species in urban Nanchang. In contrast, proline dominated both total free amino acids (FAAs) and total combined amino acids (CAAs) in suburban Guiyang. We found that oxidative degradation can significantly promote the release of FAAs, especially glycine, from CAAs in Nanchang. The controlled experiment on protein oxidation by hydroxyl radical suggested that the contribution of free glycine to the total FAA fraction tended to increase during the oxidative degradation of CAAs, supporting the predominance of glycine in FAAs in Nanchang and most previous observations. The composition of FAAs was mainly influenced by primary sources in suburban Guiyang with weak atmospheric degradation of PrM. These results suggest that the degradation of aerosol PrM by atmospheric oxidants can be responsible for the difference in FAA composition between the biosphere and the atmosphere, and also imply that the oxidative degradation of aerosol PrM may be a potential source of secondary organic nitrogen compounds in aerosols. Thus, this study can improve the current understanding of the composition characteristics of PrM in the biosphere and the atmosphere, as well as the liquid phase reactions of proteinaceous compounds with atmospheric oxidants. Plain Language Summary: Proteinaceous matter (PrM) is a ubiquitous component in both the biosphere and the atmosphere, which has seen intense research over years. This study, for the first time, combines a large amount of observational data with controlled experiments to reveal the potential atmospheric transformation of combined and free amino acids. The observed increase in the mass fraction of glycine in the total free amino acids from the biosphere to the atmosphere can be attributed to the fact that glycine has a higher release potential from the oxidative degradation of combined amino acids and is more resistant to further oxidative degradation. The overall results provide field evidence for the strong dependence of free glycine release from aerosol PrM on the hydroxyl radical, likely improving the current understanding of the composition characteristics of PrM and the multiphase reactions of proteinaceous compounds with atmospheric oxidants. Key Points: Atmospheric oxidation can cause an increase in the contribution of Gly to the aerosol TFAA fraction from the biosphere to the atmosphereThe controlled experiment suggests that the contribution of Gly to the TFAA fraction increased during the oxidative degradation of combined amino acidsThe composition profile of aerosol free amino acids depends on the oxidative degradation of proteinaceous matter after release from the biosphere to the atmosphere [ABSTRACT FROM AUTHOR]

Aim3,4-Dihydroxyl-phenyl lactic acid (DLA) and notoginsenoside R1 (R1) are known to protect ischemia and reperfusion (I/R) injury by targeting Sirtuin1/NADH dehydrogenase (ubiquinone) 1 alpha subcomplex 10/the Mitochondrial Complex I (Sirt-1/NDUFA10/Complex I) and Rho-associated kinase/adenosine triphosphate (ROCK/ATP) ATP synthase δ subunit (ATP 5D), respectively. We hypothesized that a composite of the two may exhibit a more potent effect on I/R injury. The study was designed to test this hypothesis.Materials and MethodsMale Sprague–Dawley rats underwent left anterior descending artery occlusion and reperfusion, with or without DLA, R1, or a combination of 3,4-dihydroxyl-phenyl lactic acid and notoginsenoside R1 (DR) pretreatment. Heart function, myocardial morphology, myocardial infarct, myocardial blood flow (MBF), apoptosis, vascular diameter, and red blood cell (RBC) velocity in venules were evaluated. Myeloperoxidase (MPO), malondialdehyde (MDA), and 8-oxo-deoxyguanosine (8-OHdG) were assessed. The content of ATP, adenosine diphosphate (ADP), and adenosine monophosphate (AMP), the activity of mitochondrial respiratory chain Complex I and its subunit NDUFA10, the Mitochondrial Complex V (Complex V) and its subunit ATP 5D, Sirt-1, Ras homolog gene family, member A (RhoA), ROCK-1, and phosphorylated myosin light chain (P-MLC) were evaluated. R1 binding to Sirt-1 was determined by surface plasmon resonance.ResultsDLA inhibited the expression of Sirt-1, the reduction in Complex I activity and its subunit NDUFA10 expression, the increase in MPO, MDA, and 8-OhdG, and apoptosis. R1 inhibited the increase in the expression of RhoA/ROCK-1/P-MLC, the reduction of Complex V activity and its subunit ATP 5D expression, alleviated F-actin, and myocardial fiber rupture. Both DLA and R1 reduced the myocardial infarction size, increased the velocities of RBC in venules, and improved MBF and heart function impaired by I/R. DR exhibited effects similar to what was exerted, respectively, by DLA and R1 in terms of respiratory chain complexes and related signaling and outcomes, and an even more potent effect on myocardial infarct size, RBC velocity, heart function, and MBF than DLA and R1 alone.ConclusionA combination of 3,4-dihydroxyl-phenyl lactic acid and notoginsenoside R1 revealed a more potent effect on I/R injury via the additive effect of DLA and R1, which inhibited not only apoptosis caused by low expression of Sirt-1/NDUFA10/Complex I but also myocardial fiber fracture caused by RhoA/ROCK-1 activation and decreased expression of ATP/ATP 5D/Complex V.

BackgroundT89, a traditional Chinese medicine, has passed phase II, and is undergoing phase III clinical trials for treatment of ischemic cardiovascular disease by the US FDA. However, the role of T89 on isoproterenol (ISO)-induced cardiac injury is unknown. The present study aimed to explore the effect and underlying mechanism of T89 on ISO-induced cardiac injury.MethodsMale Sprague-Dawley rats received subcutaneous injection of ISO saline solution at 24 h intervals for the first 3 days and then at 48 h intervals for the next 12 days. T89 at dose of 111.6 and 167.4 mg/kg was administrated by gavage for 15 consecutive days. Rat survival rate, cardiac function evaluation, morphological observation, quantitative proteomics, and Western blotting analysis were performed.ResultsT89 obviously improved ISO-induced low survival rate, attenuated ISO-evoked cardiac injury, as evidenced by myocardial blood flow, heart function, and morphology. Quantitative proteomics revealed that the cardioprotective effect of T89 relied on the regulation of metabolic pathways, including glycolipid metabolism and energy metabolism. T89 inhibited the enhancement of glycolysis, promoted fatty acid oxidation, and restored mitochondrial oxidative phosphorylation by regulating Eno1, Mcee, Bdh1, Ces1c, Apoc2, Decr1, Acaa2, Cbr4, ND2, Cox 6a, Cox17, ATP5g, and ATP5j, thus alleviated oxidative stress and energy metabolism disorder and ameliorated cardiac injury after ISO. The present study also verified that T89 significantly restrained ISO-induced increase of HSP70/HSP40 and suppressed the phosphorylation of ERK, further restored the expression of CX43, confirming the protective role of T89 in cardiac hypertrophy. Proteomics data are available via ProteomeXchange with identifier PXD024641.ConclusionT89 reduced mortality and improves outcome in the model of ISO-induced cardiac injury and the cardioprotective role of T89 is correlated with the regulation of glycolipid metabolism, recovery of mitochondrial function, and improvement of myocardial energy.

The present study aimed to dry jamun pulp (Syzygium cumini) by combining infrared and microwave energy in refractance window drying. The two different sets of experiments were planned using the hybrid design. The three independent parameters considered for the infrared refractance window drying (IR-RWD) included infrared lamp power (30–70% of the 1000 W lamp), pulp layer thickness (1–3 mm), and distance between the lamp and pulp layer (3.42–6.60 cm). In microwave refractance window drying (MW-RWD), the independent variables were oven-set microwave power (150–450 W), pulp layer thickness (1–3 mm), and power density (1–2.5 W g−1). The optimum conditions in IR-RWD were 40.75% infrared lamp power, 1 mm pulp layer thickness, and 3.42 cm distance between the lamp and pulp layer, resulting in dry jamun flakes with 17.93 ± 0.32 mg GAE g−1 total phenolic content, 4.37 ± 0.13 color change, 8.90 ± 0.22 mg QE g−1 total flavonoid content, and 179.05 ± 2.17 C3G mg/100g total anthocyanin content. In the case of MW-RWD, the optimum conditions were 212.4 W oven-set microwave power, 3 mm pulp layer thickness, and 2.2 W g−1 power density, resulting in 15.68 ± 0.28 mg GAE g−1 total phenolic content, 8.47 ± 0.25 color change, 8.20 ± 0.21 mg QE g−1 total flavonoid content, and 149.72 ± 1.81 C3G mg/100g total anthocyanin content. The Page model can precisely describe the jamun pulp drying behavior of IR-RWD and MW-RWD. Also, apparent moisture diffusivity was estimated in both drying methods. IR-RWD was found to be a better drying method than MW-RWD in terms of drying rates and the quality parameters of the dry jamun flakes. [ABSTRACT FROM AUTHOR]

Nitrogen-containing organic compounds (NOCs) are abundant and important aerosol components, deeply involving in global nitrogen cycle. However, the sources and formation processes of NOCs remain largely unknown, particularly in the city (Urumqi, China) farthest from the ocean worldwide. Here, NOCs in PM2.5 collected in Urumqi over a one-year period were characterized by ultrahigh-resolution mass spectrometry. The abundance of CHON compounds (mainly poor-O unsaturated aliphatic-like species) in the positive ion mode was higher in the warm period than in the cold period, which was largely attributed to the contribution of fresh biomass material combustion (e.g., forest fires) associated with amidation of unsaturated fatty acids in the warm period, rather than the oxidation processes. However, CHON compounds (mainly nitro-aromatic species) in the negative ion mode increased significantly in the cold period, which was tightly related to old-age biomass combustion (e.g., dry straws) in wintertime Urumqi. For CHN compounds, we found that alkyl nitriles and aromatic CNH compounds showed higher abundance in the warm and cold periods, respectively. It further confirmed different impacts of the combustion of fresh- and old-age biomass materials on NOC compositions. Our results clarify the mechanisms by which fresh and old-age biomass materials emitted different NOCs. [ABSTRACT FROM AUTHOR]

Vacuum steam pulsed blanching (VSPB) was employed as a novel blanching technology on Cornus officinalis to soften the tissue for subsequent coring and dehydration. The current work aims to explore its effect on mass transfer behavior, PPO inactivation, drying characteristics, physicochemical properties, antioxidant capacity, and microstructure of C. officinalis. Results showed that VSPB increased water loss, decreased solid gain, and increased weight reduction with increased blanching cycles. Besides, VSPB significantly changed physical properties and extensively reduced drying time which was attributed to the cell wall components dissolving and cell turgor pressure decreasing, also verified by observing microstructure alteration. PPO was completely denatured after blanching in 6 cycles, but phenolic compounds were still diffused or degraded. Notably, the content of flavonoids and antioxidant capacity significantly increased compared to fresh samples probably due to increased extractability caused by the disrupting cell structure. Besides, the carotenoids and ascorbic acid could be well preserved. [ABSTRACT FROM AUTHOR]

Abstract Cardiac arrhythmias associated with intracellular calcium inhomeostasis are refractory to antiarrhythmic therapy. We hypothesized that late sodium current (I Na) contributed to the calcium-related arrhythmias. Monophasic action potential duration at 90% completion of repolarization (MAPD90) was significantly increased and ventricular arrhythmias were observed in hearts with increased intracellular calcium concentration ([Ca2+]i) by using Bay K 8644, and the increase became greater in hearts treated with a combination of ATX-II and Bay K 8644 compared to Bay K 8644 alone. The prolongations caused by Bay K 8644 and frequent episodes of ventricular tachycardias, both in absence and presence of ATX-II, were significantly attenuated or abolished by late I Na inhibitors TTX and eleclazine. In rabbit ventricular myocytes, Bay K 8644 increased I CaL density, calcium transient and myocyte contraction. TTX and eleclazine decreased the amplitude of late I Na, the reverse use dependence of MAPD90 at slower heart rate, and attenuated the increase of intracellular calcium transient and myocyte contraction. TTX diminished the phosphorylation of CaMKII-δ and Nav 1.5 in hearts treated with Bay K 8644 and ATX-II. In conclusion, late I Na contributes to ventricular arrhythmias and its inhibition is plausible to treat arrhythmias in hearts with increased [Ca2+]i