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A magnetic amplifier (Magamp) postregulator using a time-sharing control strategy is proposed when using a multioutput LLC series resonant converter. The operating principles of the proposed converter and the Magamp postregulator are analyzed in detail. Furthermore, the design criterion for the Magamp core is presented, and the dead-time problem of the Magamp postregulator is analyzed. Compared with a flyback converter, the dead-time impact in the LLC structure is much better for two main reasons. The first one is that there is no reverse-recovery resetting effect for the Magamp postregulator in an LLC topology, and the second is that, when the same dead time is applied in both converters, the effect is better by using an LLC topology than a flyback topology. Finally, an experimental prototype of 310-V input and 24-V/3-A and 18-V/2-A outputs was built and tested to verify the zero-voltage-switching (zero-current-switching) operation and the high cross-regulating ratio. The experimental results prove that the dead-time impact over a Magamp in an LLC converter is much better than that when using a flyback converter, since a high cross-regulating ratio was easily achieved without using complicate resetting methods or large dead load. [ABSTRACT FROM AUTHOR]

Background: The influence of epiphytic microbiota and chemical composition on fermentation quality and microbial community of Italian ryegrass silage was evaluated. Italian ryegrass harvested at the filling stage (FS) and the dough stage (DS) was sterilized by gamma-ray irradiation and inoculated as follows: (I) FS epiphytic microbiota + irradiated FS (FF); (II) FS epiphytic microbiota + irradiated DS (FD); (III) DS epiphytic microbiota + irradiated DS (DD); (IV) DS epiphytic microbiota + irradiated FS (DF)., Results: After 60 days of ensiling, silage made from irradiated FS had a lower pH and ammonia nitrogen (NH 3 -N) content and a higher lactic acid (LA) content than that made from irradiated DS. Similarly, silage inoculated with the epiphytic microbiota of DS had a lower pH and NH 3 -N content and a higher LA content than that inoculated with the epiphytic microbiota of FS. However, LA-type fermentation (lactic acid:acetic acid > 2:1) was presented at DF and DD. The principal coordinates analysis showed that the distance between FF and DF and FD and DD was closer than other treatments, suggesting that the microbial community of silages made from irradiated FS (or DS) was more similar., Conclusion: The epiphytic microbiota played a more important role in the fermentation type, whereas the chemical composition had a great influence on the contents of fermentation end-products. However, chemical composition had a stronger effect on the microbial community of silage than the epiphytic microbiota. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

This study was designed to evaluate the effects of epiphytic microbiota from Italian ryegrass (IRIR), Napier grass (IRNP) and Sudan grass (IRSD) on ensiling characteristics and microbial community of Italian ryegrass silage. Each treatment was prepared in triplicate and ensiled in plastic bag silos for 1, 3, 7, 14, 30 and 60 days. The γ-ray irradiation sterilization method, microbiota transplantation and next generation sequencing technology were used. Results indicated that significantly (P < 0.05) higher ratio of lactic acid to acetic acid, and lower acetic acid and ammonia nitrogen contents were observed in IRNP than IRIR and IRSD after 60 days of ensiling. Lactobacillus was the most predominant in each treatment at the late stage of fermentation. Lactococcus was eventually replaced by Lactobacillus in IRSD, whereas higher abundance of Lactococcus was continuously found in IRNP. Co-occurrence network analysis demonstrated Lactococcus was pivotal in determining the silage fermentation pattern of Italian ryegrass. According to the 16S rRNA gene-predicted functional profiles, the metabolism of amino acids was enhanced by the epiphytic microbiota from Italian ryegrass and Sudan grass, while the carbohydrate metabolism was accelerated by the epiphytic microbiota from Napier grass. Overall, IRNP had a homo-fermentative process, whereas IRIR and IRSD possessed a hetero-fermentative pattern. The Lactococcus and heterofermentative Lactobacillus were mainly responsible for this. It also confirmed that the exogenous microorganisms that promote the carbohydrate metabolism and inhibit the metabolism of amino acids could be a good potential source to improve the silage quality of temperate grass., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The objective of this study was to explore the microbiological factors that cause the difference in silage fermentation characteristics between grass and legume. Specifically, the effects of epiphytic microbiota from alfalfa, oat and Italian ryegrass on ensiling characteristics and microbial community of alfalfa were assessed. By γ-ray irradiation sterilization and microbiota transplantation technology, the sterile alfalfa was inoculated as follows: (i) aseptic water (STAL); (ii) epiphytic bacteria from alfalfa (ALAL); (iii) epiphytic bacteria from oat (ALOT); (iv) epiphytic bacteria from Italian ryegrass (ALIR). Alfalfa at the initial flowering stage was ensiled in laboratory-scale silos for 1, 3, 7, 14, 30 and 60 days. Compared with ALAL and ALIR, higher lactic acid contents and ratio of lactic acid to acetic acid, and lower acetic acid, propionic acid, ethanol and ammonia nitrogen contents were observed in ALOT after 60 days of fermentation. In each treated group, Lactobacillus was the most dominant genus after 60 days of ensiling. Relatively higher abundance of Weissella, Hafnia-Obesumbacterium, Enterobacteriaceae or hetero-fermentative Lactobacillus was found in ALAL and ALIR after 60 days. Co-occurrence network analysis proved Pediococcus and Lactococcus were pivotal in deciding the fermentation pattern of alfalfa silage. According to the 16S rRNA gene-predicted functional profiles, the metabolism of amino acids was inhibited by the epiphytic microbiota from oat. Overall, ALOT showed a homo-fermentative process, whereas ALAL and ALIR exhibited a hetero-fermentative pattern. Furthermore, the exogenous microorganisms inhibiting the metabolism of amino acids can be a good potential source to improve the silage quality of legume forage., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Napier grass (Pennisetum purpureum) is well-known due to its high biomass production. The epiphytic microbiota was prepared from Napier, alfalfa, and red clover grass and served as an inoculum. The chopped sterilized Napier grass was inoculated with reconstituted epiphytic microbiota, and treatments were designed as: distilled water (N0); Napier grass epiphytic microbiota (NP); alfalfa epiphytic microbiota (AL); and red clover epiphytic microbiota (RC). The results reveal that the reconstituted epiphytic microbiota bacteria efficiently adapted in Napier grass silage, improved fermentation, and produced lactic acid. The alfalfa-grass inoculum rapidly dropped pH and enhanced the lactic acid (LA) and the ratio of lactic acid-to-acetic acid (LA/AA) during the entire ensiling process. However, red clover attains high lactic acid, while Napier grass produces high acetic acid-type fermentation at terminal silage. After day 60 of ensiling, Lactobacillus proportion was higher in AL (85.45%), and RC (59.44%), inocula as compared with NP (36.41%), inoculum. The NP inoculum terminal silage was diverse than AL and RC inocula and dominated by Enterobacter (16.32%) and Enterobacteriaceae (10.16%) and also significantly (p < 0.05) higher in acetic acid. The present study concluded that AL and RC epiphytic microbiota successfully develop and more efficient than Napier grass microbiota. It is suggested that abundant microbiota isolate from alfala and red clover and develop more economical and efficient inocula for quality fermentation of Napier grass silage in practice., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study aimed to evaluate the effects of exogenous epiphytic microbiota inoculation on the fermentation quality and microbial community of sudan grass silage. Gamma irradiated sudan grass was ensiled with distilled water (STR), epiphytic microbiota of sudan grass (SUDm), forage sorghum (FSm), napier grass (NAPm) and whole crop corn (WCCm). The FSm inoculated silage have significantly lower lactic acid (LA) concentration and higher pH during early ensiling, while LA concentration gradually and significantly increased with the progression of ensiling and have lower pH in relation to other treatments for terminal silage. Inoculation of NAPm resulted in lower LA and higher acetic acid (AA) concentrations, higher pH, ammonia-N and dry matter losses for terminal silage, followed by SUDm silage. Inoculations of WCCm significantly increased LA production and pH decline during early ensiling and have higher LA and pH then NAPm and SUDm silages during final ensiling. The early fermentation of SUDm silage was dominated by genus of Pediococcus. The genera of Lactobacillus were predominant in WCCm and NAPm silages during 3 days of ensiling, while Weissella dominated initial microbial community of FS silage. The terminal silage of NAPm was dominated by Enterobacter and Rosenbergiella, while Enterobacter and Lactobacillus dominated terminal SUDm silage. The final silage of FSm was dominated by Lactobacillus, Weissella and Pediococcus, while Lactobacillus and Acetobacter dominated terminal WCCm silages. The results demonstrated that among the four forages the epiphytic microbiota from forage sorghum positively influenced the microbial community and fermentability of sudan grass silage.

The study investigated the effects of transplantation and reconstitution of indigenous and exogenous epiphytic microbiota on the fermentation quality and microbial community of red clover silage. Sterile red clover was inoculated with distilled water (RC0), extracted epiphytic microbiota of red clover (RC), maize (MZ), and sorghum (SG). RC inoculation rapidly decreased pH at the onset of ensiling. The LA concentration and ratio of LA/AA were higher in RC silage during entire ensiling while MZ silage during late phase of ensiling. Pediococcus was dominant in RC early silage, while Lactobacillus was abundant in MZ final silage. The SG terminal silage had higher pH (>4.50) and dominated by Sphingomonas, Enterobacter, and Novosphingobium. RC and MZ microbiota were beneficial in enhancing fermentation quality and microbial community in red clover silage. Transplantation and reconstitution of epiphytic microbiota can be a successful method to assess the effective and eco-friendly additive for the targeted crop., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This study was aimed to assess the effects of exogenous microbiota on fermentation quality and bacterial community dynamics in oat (OT) silage. The irradiated OT was treated with the following: (i) sterile water (STOT); (ii) epiphytic microbiota on oat (OTOT); (iii) epiphytic microbiota on maize (OTMZ); (iv) epiphytic microbiota on sorghum (OTSG). γ-Ray irradiation, microbiota transplantation and sequencing methods were firstly used. After 60 days of ensiling, OTMZ group had higher lactic acid (LA) and lower acetic acid (AA) contents than OTOT group. Inversely, lower LA content and higher ratio of LA to AA was observed in OTSG group than OTOT group. Lactobacillus was predominant in OTMZ-60 group, while Lactobacillus and Enterobacteriaceae were both dominant in OTSG-60 group. Overall, the higher amounts of Enterobacteriaceae and heterofermentative Lactobacillus are conductive to acetic acid-type fermentation, and forage microbiota transplantation may be a potential way to identify the role of microbe during ensiling., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This study analyzed the feasibility and effects of exogenous epiphytic microbiota on the fermentation quality and microbial community of whole crop corn. Gamma irradiated whole crop corn was ensiled with distilled water (STR), extracted microbiota of whole crop corn (WCC), Napier grass (NAP), forage sorghum (FS) or Sudan grass (SUD). WCC significantly increased LA concentration and decreased the pH during early ensiling. FS had significantly higher LA and lower pH during terminal ensiling. NAP caused higher pH and AA followed by the SUD silage. During 3 d of ensiling WCC and FS silage was dominated by Lactobacillus and Lactococcus while Weissella dominated NAP and SUD silage. Terminal silage was dominated by Lactobacillus in FS and Acinetobacter in NAP while Lactobacillus, Acetobacter, Acinetobacter and Sphingobium dominated WCC and SUD silage. The study demonstrated that FS microbiota transplantation positively influenced the microbial community and fermentation quality of whole crop corn silage as compared to other microbiota., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Ltd.)

Diabetes mellitus is a disease caused by innate or acquired insulin deficiency, resulting in altered glucose metabolism and high blood glucose levels. Chronic hyperglycemia is linked to development of several ocular pathologies affecting the anterior segment, including diabetic corneal neuropathy and keratopathy, neovascular glaucoma, edema, and cataracts leading to significant visual defects. Due to increasing disease prevalence, related medical care costs, and visual impairment resulting from diabetes, a need has arisen to devise alternative systems to study molecular mechanisms involved in disease onset and progression. In our current study, we applied a novel 3D in vitro model of the human cornea comprising of epithelial, stromal, and neuronal components cultured in silk scaffolds to study the pathological effects of hyperglycemia on development of diabetic corneal neuropathy. Specifically, exposure to sustained levels of high glucose, ranging from 35 mM to 45 mM, were applied to determine concentration-dependent effects on nerve morphology, length and density of axons, and expression of metabolic enzymes involved in glucose metabolism. By comparing these metrics to in vivo studies, we have developed a functional 3D in vitro model for diabetic corneal neuropathy as a means to investigate corneal pathophysiology resulting from prolonged exposure to hyperglycemia.

Objective: Four lactic acid bacteria (LAB) strains isolated from common vetch, tall fescue and perennial ryegrass on the Tibetan Plateau were characterized, and their effects on the fermentation quality of Italian ryegrass ( Lolium multiflorum Lam.) silage were studied., Methods: The four isolated strains and one commercial inoculant (G, Lactobacillus plantarum MTD-1) were evaluated using the acid production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. The five LAB strains were added to Italian ryegrass for ensiling at three different temperatures (10°C, 15°C, and 25°C)., Results: All isolated strains (LCG3, LTG7, I5, and LI3) could grow at 5°C to 20°C, pH 3.0 to 8.0 and NaCl (3.0%, 6.5%). Strains LCG3, LTG7, I5, and LI3 were identified as Lactobacillus plantarum , Pediococcus acidilactici , Lactobacillus paraplantarum , and Lactobacillus casei by sequencing 16S rDNA, respectively. All LAB inoculants significantly (p<0.05) increased lactic acid (LA) contents and ratios of lactic acid to acetic acid, and reduced pH and ammonia nitrogen/total nitrogen (AN/TN) compared with uninoculated silages at various temperatures (10°C, 15°C, and 25°C). Compared to the commercial inoculant G, I5, and LI3 showed similar effects on improving the silage quality of Italian ryegrass at 10°C and 15°C, indicated by similar pH, LA content and AN/TN., Conclusion: All inoculants could improve the silage fermentation quality at various temperatures (10°C, 15°C, and 25°C). At the temperature of 10°C and 15°C, strain I5 and LI3 had similar effects with the commercial inoculant G on improving the silage quality of Italian ryegrass.

The interactions between corneal nerve, epithelium, and stroma are essential for maintaining a healthy cornea. Thus, corneal tissue models that more fully mimic the anatomy, mechanical properties and cellular components of corneal tissue would provide useful systems to study cellular interactions, corneal diseases and provide options for improved drug screening. Here a corneal tissue model was constructed to include the stroma, epithelium, and innervation. Thin silk protein film stacks served as the scaffolding to support the corneal epithelial and stromal layers, while a surrounding silk porous sponge supported neuronal growth. The neurons innervated the stromal and epithelial layers and improved function and viability of the tissues. An air-liquid interface environment of the corneal tissue was also mimicked in vitro, resulting in a positive impact on epithelial maturity. The inclusion of three cell types in co-culture at an air-liquid interface provides an important advance for the field of in vitro corneal tissue engineering, to permit improvements in the study of innervation and corneal tissue development, corneal disease, and tissue responses to environmental factors., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Peripheral nerve regeneration may be enhanced through the use of biodegradable thin film biomaterials as highly tuned inner nerve conduit liners. Dorsal root ganglion neuron and Schwann cell responses were studied on protein films comprising silk fibroin blended with recombinant human tropoelastin protein. Tropoelastin significantly improved neurite extension and enhanced Schwann cell process length and cell area, while the silk provided a robust biomaterial template. Silk-tropoelastin blends afforded a 2.4-fold increase in neurite extension, when compared to silk films coated with poly-d-lysine. When patterned by drying on grooved polydimethylsiloxane (3.5 μm groove width, 0.5 μm groove depth), these protein blends induced both neurite and Schwann cell process alignment. Neurons were functional as assessed using patch-clamping, and displayed action potentials similar to those cultured on poly(lysine)-coated glass. Taken together, silk-tropoelastin films offer useful biomaterial interfacial platforms for nerve cell control, which can be considered for neurite guidance, disease models for neuropathies and surgical peripheral nerve repairs., (Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)