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A putative nucleopolyhedrovirus (NPV) from a field-collected local Spodoptera picta population was isolated for the first time. Its pathogenesis was described in S. picta larvae and was tentatively assigned the name Spodoptera picta nucleopolyhedrovirus or SppiNPV. With the objective of utilizing this SppiNPV as a biological control agent, its cross-infectivity to S. litura – a very important agricultural pest in the country – was evaluated. Third instar S. litura larvae were infected with approximately 100 occlusion bodies (OBs) of SppiNPV using artificial diet- incorporation. SppiNPV infection in S. litura was clearly observed as the 4th instar larvae exhibited pinkish coloration, a characteristic sign of NPV-infection. In addition, the integument of the mildly-infected larvae easily twisted when touched and often expelled slimy fluid from their mouth. At the advanced stage of infection, larvae became extremely fragile resulting in cuticles that were easily ruptured. At 6 d post-infection (dpi), 20% mortality was observed in the SppiNPV-treated S. litura. At 16 dpi, all the cutworms in the control set-up emerged as normal adults, while only three cutworms (10%) in the NPV-treated larvae emerged as adults but with short malformed wings and abnormally soft and fragile abdomen. The effect of SppiNPV on the weight gain of S. litura larvae was also monitored at 4 and 6 dpi. Although significantly higher weight (F = 5.09; df = 58; P > 0.0278) was recorded in the untreated cutworms than the NPV-treated cutworms at 4 dpi, weight gain did not significantly differ in SppiNPV-infected and untreated larvae. Overall, a significantly higher mortality of 46.67% (F = 25.37; df = 58; P > 0.0001) was recorded in SppiNPV-infected cutworm larvae. Further studies to characterize this novel SppiNPV, increase its virulence to S. litura through the continuous passage in S. litura, and optimize the amount of OB to be applied to ensure 100% mortality are recommended so that it can be used as a biological control agent with expanded host range.

The mechanical and radiation shielding properties for the PbO–MoO3–Li2O–B2O3 glass system were theoretically investigated in this paper. The PbO–MoO3–Li2O–B2O3 glass system (coded as investigated glasses) was fabricated using the melt quenching mechanism. The optical packing density (OPD) increases from 75.563 to 84.366, and oxygen molar volume (OMV) decreases from 13.234 to 11.853 cm3/mol when increasing the PbO concentration. The values of elastic moduli decreased from 47.06 to 39.67 GPa for Young, from 33.51 to 32.41 GPa for bulk, from 19.82 to 16.29 GPa for shear and from 59.94 to 54.14 GPa for longitudinal moduli as the PbO is increased. The radiation attenuation characteristics were reported at the photon energies used in diagnostic radiology. The mass attenuation coefficient (MAC) was evaluated using the three photoatomic data libraries EPICS2017, EPDL97, and XCOM, available in the EpiXS and Phy-X programs. The MAC for the five investigated glasses at 20 keV was much higher than the MAC at 40, 60 and 80 keV. The MAC for investigated glasses increased with the addition of PbO, with Pb-S1 demonstrating the lowest MAC, and Pb-S5 demonstrating the highest MAC. Additionally, the rate of the increment of MAC at 20 keV as the concentration of PbO increased was higher than that at 40, 60 and 80 keV. The effective atomic number (EAN) was determined using Phy-X program. The EAN follows the trend: Pb-S5 > Pb-S4 > Pb-S3 > Pb-S2 > Pb-S1. The EAN results proved that the glass with low amounts of B2O3 and higher amounts of PbO had good attenuation features. The EAN had the maximum values of 73.55–76.67 at 20 keV, whereas the lowest values occurred at 80 keV and varied between 53.63 and 63.39. The half-value layer (HVL) results showed that the Pb-S1 glass had the greatest HVL, while Pb-S5 had the least. There is a higher discrepancy between the tenth-value layer values at 80 keV than at 20 keV. At 20 keV, the difference between the highest and lowest TVL values (Pb-S1 and Pb-S5) was only 0.004 cm, while the difference at 80 keV was 0.152 cm. Pb-S5 is the most space-efficient radiation shield.