Optimization of overproducing S-adenosyl-Lmethionine Saccharomyces cerevisiae S-W55 mutant utilizing unpolished rice from aging paddy by feeding Lmethionine

The medium and fed-batch fermentation by Saccharomyces cerevisiae S-W55 were optimized. The unpolished rice from aging paddy was used as major nutrient source to reduce the raw material cost of SAM fermentation. The unpolished rice saccharificate (URS) and yeast extract were employed as carbon source and nitrogen source, respectively. The dosages of URS and yeast extract in the medium compositions were optimized by response surface methodology (RSM). As a result, when the fermentation was carried out under the optimal conditions for URS (51.4 g/L) and yeast extract (4.74 g/L), the SAM yield reached 2.61 g/L. Some fed-batch processes by adding L-methionine (MET) were investigated. Adding MET into the fermentation broth at one time at the time of high cell density reaching 80 g/L could get better results with the optimal SAM concentration of 5.3 g/L and biomass yield of 89.1 g/L. By feeding MET into the fermentation broth at a feeding rate of 2 g/h for 5 h at the time of high cell density reaching 80 g/L, the optimal results were reached and the maximal SAM yield and biomass density were 5.82 and 90.2 g/L, respectively. It indicated that, the fed-batch at high cell density would be more propitious to the SAM biosynthesis.Key words: Unpolished rice saccharificate, S-adenosyl-L-methionine, fermentation optimization, fed-batch fermentation, Saccharomyces cerevisiae

Exercise-Induced Changes in Exhaled NO Differentiates Asthma With or Without Fixed Airway Obstruction From COPD With Dynamic Hyperinflation.

Asthmatic patients with fixed airway obstruction (FAO) and patients with chronic obstructive pulmonary disease (COPD) share similarities in terms of irreversible pulmonary function impairment. Exhaled nitric oxide (eNO) has been documented as a marker of airway inflammation in asthma, but not in COPD. To examine whether the basal eNO level and the change after exercise may differentiate asthmatics with FAO from COPD, 27 normal subjects, 60 stable asthmatics, and 62 stable COPD patients were studied. Asthmatics with FAO (n = 29) were defined as showing a postbronchodilator FEV(1)/forced vital capacity (FVC) ≤70% and FEV(1) less than 80% predicted after inhaled salbutamol (400 μg). COPD with dynamic hyperinflation (n = 31) was defined as a decrease in inspiratory capacity (ΔIC%) after a 6 minute walk test (6MWT). Basal levels of eNO were significantly higher in asthmatics and COPD patients compared to normal subjects. The changes in eNO after 6MWT were negatively correlated with the percent change in IC (r = −0.380, n = 29, P = 0.042) in asthmatics with FAO. Their levels of basal eNO correlated with the maximum mid-expiratory flow (MMEF % predicted) before and after 6MWT. In COPD patients with air-trapping, the percent change of eNO was positively correlated to ΔIC% (rs = 0.404, n = 31, P = 0.024). We conclude that asthma with FAO may represent residual inflammation in the airways, while dynamic hyperinflation in COPD may retain NO in the distal airspace. eNO changes after 6MWT may differentiate the subgroups of asthma or COPD patients and will help toward delivery of individualized therapy for airflow obstruction

Time-resolved resonance Raman spectroscopy and density functional theory investigation of the CH2I-I isomer and CH2I2⋯I molecular complex products produced from ultraviolet photolysis of CH2I2 in the solution phase

The CH2I-I isomer and CH2I2···I molecular complex products produced from ultraviolet photolysis of CH2I2 in the solution phase was analyzed by using time-resolved resonance Raman spectroscopy. The structure and properties of the CH2I-I species and the CH2I2···I molecular complex and their reaction towards ethylene were compared. The results showed that the CH2I-I isomer reacts with ethylene to produce a cyclopropane product and I2 leaving group via a single step and low barrier to reaction.published_or_final_versio

Sub-6GHz 4G/5G Conformal Glasses Antennas

© 2013 IEEE. The difficulty of antenna design applied to glasses is that the structure of glasses is too single, and the space available for antenna design is greatly limited. In this background, the integrated design of 4G antennas and 5G antennas applied to glasses is proposed in this paper. The most important highlight of this design is that it makes full use of the limited three-dimensional space structure provided by glasses and achieves the perfect combination of the antenna and glasses in the physical structure. Specifically, two antennas for 4G communication are arranged on two glasses frames, and four antennas for 5G communication are arranged on two glasses legs. In this way, we can make full use of the space provided by the glasses to design antennas and ensure that there is a certain distance between the 4G antennas and 5G antennas so that the performance of both 4G antennas and 5G antennas can be guaranteed. The 4G antenna consists of a loop structure printed on the frame and leg of the glasses and a parasitic branch strip printed on the front of the leg of the glasses. The resonance modes of the 4G antenna are mainly loop, monopole, and dipole modes, which can cover two 4G bands of 0.824-0.96 GHz and 1.71-2.69 GHz. Each 5G antenna mainly comes from the open slot mode etched on the metal ground surface of an FR4 substrate of the glasses leg. In addition, the slot antennas operate in two 5G bands of 3.3-3.6 GHz and 4.8-5.0 GHz. Finally, the glasses and the antennas are fabricated based on FR4 substrates and measured. The measured results show that the proposed antennas perform well and have the potential to be used in 4G/5G communications through glasses

Slow cooling and efficient extraction of C-exciton hot carriers in MoS2 monolayer

In emerging optoelectronic applications, such as water photolysis, exciton fission and novel photovoltaics involving low-dimensional nanomaterials, hot-carrier relaxation and extraction mechanisms play an indispensable and intriguing role in their photo-electron conversion processes. Two-dimensional transition metal dichalcogenides have attracted much attention in above fields recently; however, insight into the relaxation mechanism of hot electron-hole pairs in the band nesting region denoted as C-excitons, remains elusive. Using MoS2 monolayers as a model two-dimensional transition metal dichalcogenide system, here we report a slower hot-carrier cooling for C-excitons, in comparison with band-edge excitons. We deduce that this effect arises from the favourable band alignment and transient excited-state Coulomb environment, rather than solely on quantum confinement in two-dimension systems. We identify the screening-sensitive bandgap renormalization for MoS2 monolayer/graphene heterostructures, and confirm the initial hot-carrier extraction for the C-exciton state with an unprecedented efficiency of 80%, accompanied by a twofold reduction in the exciton binding energy

Structure of mitochondrial DNA control region of Argyrosomus amoyensis and molecular phylogenetic relationship among six species of Sciaenidae

The structure of the mitochondrial DNA (mtDNA) control region of Argyrosomus amoyensis was examined in this study. TAS, cTAS, CSB-D to CSB-F and CSB-1 to CSB-3 segments were detected in the species. The results indicated that the structures of these parts were different from that of most fishes. All the mtDNA control region sequences examined had missing tandem repeat sequences downstream of CSB-3, which were the same as most fishes’. In addition, part of the COI gene was used to analyze the phylogenetic relationships of six Sciaenids species. The phylogenetic tree results supported the classification by traditional morphology, and COI barcodes were useful for identifying these six species of Sciaenids.Key words: Control region, structure, Argyrosomus amoyensis, COI, phylogenetic relationship, Sciaenidae

The cultivation, bioactive components and pharmacological effects of Armillaria mellea

Armillaria mellea, a symbiotic fungus in the underground tubers of Chinese medicinal orchid Gastrodia elata, is one of the main biological active components and pharmaceutical effects of its host gastrodia. The purpose of this review is to bring attention to the biological properties of this unique A. mellea mushroom and its constituents, as well as to suggest the potential for the development of new drugs related to this fungus. It contains various known and untapped bioactive metabolites such aspolysaccharides, sesquiterpene aryl esters, steroids and fibrinolytic enzymes. It could be exploited as an important source of new biological natural products with anticonvulsant, immunomodulatory andantimicrobial functions. The batch culture is preferred as an alternative means of getting bioactive components from Armellaria fermentation. Challenges in investigations on A. mellea include the optimization of culture parameters, the further elucidation of the molecular pharmacological mechanism and relationship between structure and function of their secondary metabolites