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In this study, wood samples (Xylia Xylocarpa) with dimensions of 50 x 50 x 500 mm were dried under an absolute pressure of 0.12 - 0.217 bar at a temperature of 45 - 59°C and infrared radiation intensity of 459 - 741 W/m2 to assess their drying characteristics. The experiment planning method was used to build the equation that correlated the relationship between technological parameters of radiation intensity and drying temperature on different physicochemical properties of wood dried by the infrared vacuum drying method. The results showed that the increase of both of these conditions promoted the drying process and affected the wood quality. The more defects, the higher the radiation intensity and the higher the drying temperature was from 600 - 741 W/m2, 50 to 60°C, respectively. Therefore, to minimize wood defects and reduce drying time it was necessary to adjust the drying temperature and infrared radiation intensity. The results gave the optimal drying regime of Xylia Xylocarpa with Timin = 64.29 h and Demin = 11.6% at a drying temperature of 58.70C, infrared radiation intensity of 625.2 W/m2 and moisture content of dried wood after at 10± 1% (wb.). That contributes to finding suitable drying technology parameters, providing detailed information for businesses and researchers on the development of infrared vacuum drying technology for wood materials.

This study was undertaken to evaluate the phytoconstituents present in the seed extract of Dialium cochinchinensis for antioxidant, antimicrobial and cytotoxic properties. Results showed the presence of polyphenols, flavonoids, alkaloids, saponins, coumarins and a polyuronid compound in the D. cochinchinensis seed extract. The total polyphenol and flavonoid contents of the dry extract were 133.5±2.87 mg GAE/g and 227.0±23.20 mg Rutin equivalent/g, respectively. D. cochinchinensis seed extract exhibited antioxidant property in 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid and potassium ferricyanide reducing antioxidant power methods. Moreover, D. cochinchinensis seed extract exerted inhibitory effect on Gram-positive bacteria. Finally, D. cochinchinensis seed extract was found to be toxic to Vero cell lines and the pathogens with selectivity index ranging from 0.01 to 0.04. In conclusion, D. cochinchinensis seed extract could be considered as a new source of natural antioxidant and antimicrobial agents for research and application.

This paper presents a new high-efficiency-high-step-up based converter integrating two non-isolated secondary interleaved coupled inductors with recovery stages dedicated to smart HVDC distributed architecture in renewable energy production systems. Appropriate duty cycle ratio assumes that the two recovery stages work with parallel charge and discharge to achieve high step-up voltage gain. Besides, the voltage stress on the main switch is reduced with a passive clamp circuit and thus, low on-state resistance R dson of the main switch can be adopted to reduce conduction losses. In addition, the coupled inductors alleviate the reverse-recovery problem of the diode. Thus, the efficiency of a basic DC-HVDC converter dedicated to renewable energy production can be further improved with such topology. A prototype converter is developed, and experimentally tested for validation.

This is the first study documenting the induction of gamma-interferon (IFN-gamma) in human embryonic fibroblasts during human cytomegalovirus (HCMV) replication. Infection of cells with HCMV resulted in the consistent production of IFN-gamma RNA, as determined by RT-PCR and Northern blot analysis. Western blot analysis of cell lysates and immunoprecipitates from the cultural fluids of infected cells demonstrated the presence of IFN-gamma at the protein level. Induction of IFN-gamma required infectious HCMV, since high-dose ultraviolet inactivation of the virus stock eliminated IFN-gamma production. Further, IFN-gamma induction appears to be a late event in the virus replication cycle, since inhibition of HCMV DNA synthesis (e.g., phosphonoacetic acid) blocked the increase in IFN-gamma. Soluble factor(s) released from HCMV-infected cells apparently did not contribute to the induction of IFN-gamma, since virus stocks from which virus had been removed by sedimentation did not induce production of IFN-gamma. The appearance of IFN-gamma at late stages of HCMV infection and its elimination in the presence of an inhibitor (Actinomycin D) of RNA synthesis indicate a true transcriptional induction of this lymphokine at the RNA and protein levels. The significance of IFN-gamma production with regard to the replication and pathogenesis of HCMV in vitro and in vivo will require further investigation.