Bee venom contains a variety of peptide constituents, including low-molecular-weight protease inhibitors. While the putativelow-molecular-weight serine protease inhibitor Api m 6 containing a trypsin inhibitor-like cysteine-rich domain was identifiedfrom honeybee (Apis mellifera) venom, no anti-fibrinolytic or anti-microbial roles for this inhibitor have been elucidated.In this study, we identified an Asiatic honeybee (A. cerana) venom serine protease inhibitor (AcVSPI) that was shownto act as a microbial serine protease inhibitor and plasmin inhibitor. AcVSPI was found to consist of a trypsin inhibitor-likedomain that displays ten cysteine residues. Interestingly, the AcVSPI peptide sequence exhibited high similarity to the putativelow-molecular-weight serine protease inhibitor Api m 6, which suggests that AcVSPI is an allergen Api m 6-like peptide.Recombinant AcVSPI was expressed in baculovirus-infected insect cells, and it demonstrated inhibitory activity against trypsin,but not chymotrypsin. Additionally, AcVSPI has inhibitory effects against plasmin and microbial serine proteases; however,it does not have any detectable inhibitory effects on thrombin or elastase. Consistent with these inhibitory effects, AcVSPIinhibited the plasmin-mediated degradation of fibrin to fibrin degradation products. AcVSPI also bound to bacterial andfungal surfaces and exhibited anti-microbial activity against fungi as well as gram-positive and gram-negative bacteria. Thesefindings demonstrate the anti-fibrinolytic and anti-microbial roles of AcVSPI as a serine protease inhibitor.

Serine proteases and serine protease homologs are involved in the prophenoloxidase (proPO)-activating system leadingto melanization.The Bombyx mori serine protease homolog BmSPH-1 regulates nodule melanization. Here, we show the dualrole of BmSPH-1 in the development and immunity of B. mori. BmSPH-1 was expressed in hemocytes after molting andduring the larval-pupal transformation in normal development. In contrast, following infection, BmSPH-1 was expressed inhemocytes and activated in the hemolymph, which resulted in the induction of PO activity. Moreover, BmSPH-1 was activatedin the cuticle during the larval-pupal transformation and early pupal stages. In BmSPH-1 RNAi-treated silkworms, the reducedBmSPH-1 mRNA levels during the spinning stage or the prepupal stage resulted in the arrest of pupation or pupal cuticularmelanization, respectively. The binding assays revealed that BmSPH-1 interacts with B. mori immulectin, proPO, andproPO-activating enzyme. Our findings demonstrate that BmSPH-1 is responsible for the larval-pupal transformation, pupalcuticular melanization and innate immunity of silkworms, illustrating the dual role of BmSPH-1 in development and immunity.

Major royal jelly proteins (MRJPs) are important protein components of bee royal jelly (RJ) and exhibit various biologicaland pharmacological activities. The antimicrobial activities of royalisins and the jelleines contained within MRJP 1 andMRJP 2 in RJ have been elucidated. However, the antimicrobial effects of other bee RJ MRJPs remain largely unknown.In this study, we demonstrated that the Asiatic honeybee (Apis cerana) MRJP 4 (AcMRJP4) exhibits antimicrobial activitiesagainst bacteria, fungi, and yeast. Recombinant AcMRJP4 was expressed as a 63-kDa protein in baculovirus-infected insectcells. However, some of the recombinant AcMRJP4 proteins were cleaved into two fragments (i.e., 48-kDa (AcMRJP4-48)and 15-kDa (AcMRJP4-15) proteins) by the proteolytic cleavage of the C-terminus of the recombinant AcMRJP4. Interestingly,AcMRJP4, AcMRJP4-48, and AcMRJP4-15 exhibited antimicrobial activities, with AcMRJP4-15 exhibiting the highestantimicrobial activity, followed by AcMRJP4. AcMRJP4-15, which is a hydrophilic peptide with 88 amino acid residuesthat contains a high content of Asn and positively charged amino acids, induced structural damage in the cell walls ofthe assayed bacteria, fungi, and yeast. Altogether, our data demonstrated that AcMRJP4 functions as an antimicrobial agent.

Insect immulectins are involved in various aspects of the innate immunity, including encapsulation, melanization, and phagocytosis. Although the silkworm Bombyx mori immulectin (BmIML) has been reported previously, the ligand and functions of BmIML have not been investigated. Here, we show the dual roles of BmIML in cuticular melanization and immunity of B. mori. BmIML recognizes carbohydrates in a Ca2+-dependent manner and binds to Gram-negative and Gram-positive bacteria, fungi, and yeast. BmIML was expressed in the fat body during infections and localized to the hemocytes of silkworms. Additionally, BmIML was expressed in the epidermis during the prepupal stage and localized to the cuticle of silkworms. After treatment with E. coli, dopa, dopamine, or tyrosine injections, BmIML production was induced in the fat body but not in the epidermis of silkworms. Treatment with BmIML RNAi resulted in the arrest of pupal cuticular melanization. Therefore, we concluded that BmIML is involved in pupal cuticular melanization and innate immunity responses of silkworms, suggesting dual roles for BmIML.

In insects, serine proteases are involved in a variety of physiological processes including digestion, development, and immunity. Bombyx mori serine protease homolog BmSPH-1 regulates nodule melanization and is recruited into nodules from the hemolymph by B. mori lipopolysaccharide-binding protein. Here, we show the dual role of BmSPH-1 in development and immunity of B. mori. BmSPH-1 was expressed in the hemocytes during larval-pupal transformation and localized to the cuticle of silkworms, which indicates that BmSPH-1 is secreted from hemocytes and then transported to the cuticle via the hemolymph. BmSPH-1 was proteolytically activated in the cuticle during larval-pupal transformation and the early pupal stage. BmSPH-1 RNAi resulted in the arrest of larval-pupal transformation and pupal cuticular melanization. Furthermore, the expression of BmSPH-1 was up-regulated in the hemocytes during infection. Taken together, we found that BmSPH-1 is involved in larval-pupal transformation and pupal cuticular melanization as well as the innate immunity of silkworms, which indicates that BmSPH-1 is responsible for either development or immunity.

The BCBJ (Back Contact and Back Junction) or back-lit solar cell design eliminates shading loss by placing the pn junction and metal electrode contacts all on one side that faces away from the sun. However, as the electron-hole generation sites now are located very far from the pn junction, loss by minority-carrier recombination can be a significant issue. Utilizing Medici, a 2-dimensional semiconductor device simulation tool, the interdependency between the substrate thickness and the minority-carrier recombination lifetime was studied in terms of how these factors affect the solar cell power output. Qualitatively speaking, the results indicate that a very high quality substrate with a long recombination lifetime is needed to maintain the maximum power generation. The quantitative value of the recombination lifetime of minority-carriers, i.e., electrons in p-type substrates, required in the BCBJ cell is about one order of magnitude longer than that in the front-lit cell, i.e., 5 × 10−4 sec vs. 5 × 10−5 sec. Regardless of substrate thickness up to 150 μm, the power output in the BCBJ cell stays at nearly the maximum value of about 1.8 × 10−2 W·cm−2, or 18 mW·cm−2, as long as the recombination lifetime is 5 × 10−4 s or longer. The output power, however, declines steeply to as low as 10 mW·cm−2 when the recombination lifetime becomes significantly shorter than 5 × 10−4 sec. Substrate thinning is found to be not as effective as in the front-lit case in stemming the decline in the output power. In view of these results, for BCBJ applications, the substrate needs to be only mono-crystalline Si of very high quality. This bars the use of poly-crystalline Si, which is gaining wider acceptance in standard front-lit solar cells.

Bee venom is a complex mixture of toxic components that induces immediate local inflammatory and allergic responses. However, the presence and role of superoxide dismutase (SOD) in bee venom have not been previously investigated. Here, we provide the first demonstration that bee venom contains Cu,Zn SOD (SOD3), a novel extracellular component that promotes local inflammation. Bee venom SOD3 was shown to be an oxidant, rather than an antioxidant, that induces the inflammation-signaling molecule H2O2 in vivo. H2O2 plays a pathological role by triggering an immediate local inflammatory response. Furthermore, bee venom SOD3 significantly induced the activation of proinflammatory mediators (TNF-α and COX-2) and cytokines (IL-1β and IL-6) via the overproduction of H2O2 in mice. Our data demonstrate that bee venom SOD3 induced H2O2, which drives an immediate local inflammatory response, indicating a novel mechanism underlying bee venom-induced local inflammation.

It is clearly understood that the main benefits of e-navigation are improved safety and better protection of the environment through the promotion of standards of navigational system and a reduction in human error. In order to meet the expectations on the benefit of e-navigation, enavigation services should be more focused on non-SOLAS ships. The purpose of this paper is to present necessary e-navigation services for non-SOLAS ships in order to prevent marine accidents in Korean coastal waters. To meet the objectives of the study, an examination on the present navigation and communication system for non-SOLAS ships was performed. Based on the IMO’s e-navigation Strategy Implementation Plan (SIP) and Korea’s national SIP for e-navigation, future trends for the development and implementation of e-navigation were discussed. Consequently, Electronic Navigational Chart (ENC) download and ENC up-date service, ENC streaming service, route support service and communication support service based on Maritime Cloud were presented as essential e-navigation services for non-SOLAS ships. This study will help for the planning and designing of the Korean e-navigation system. It is expected that the further researches on the navigation support systems based on e-navigation will be carried out in order to implement the essential e-navigation services for non-SOLAS ships.

Most ectotherms mature at a larger body size in colder conditions. This negative relationship between developmental temperature and final body size is termed the temperature-size rule. In this study, we investigated how dietary protein:carbohydrate (P:C) balance modulates the fundamental relationship between temperature and body size in the final-instar caterpillars of Spodoptera litura. The magnitude and sign of the thermal reaction norm for body size were altered by the dietary P:C balance of the food eaten by caterpillars. The slope of the reaction norm was flat for caterpillars raised on a nutritionally balanced food (P:C = 1:1) but was negative for those on imbalanced foods (1:5 or 5:1). When allowed to self-compose their preferred diet, caterpillars preferred carbohydrate-rich food at higher temperatures. The negative impact of high temperature on body size was mitigated by such a temperature-driven shift in nutrient preference. This study highlights the importance of macronutrient balance as a key factor modulating the relationship between temperature and body size in insects.

In photovoltaic power generation where minority carrier generation via light absorption is competing against minority carrier recombination, the substrate thickness and material quality are interdependent, and appropriate combination of the two variables is important in obtaining the maximum output power generation. Medici, a two-dimensional semiconductor device simulation tool, is used to investigate the interdependency in relation to the maximum power output in front-lit Si solar cells. Qualitatively, the results indicate that a high quality substrate must be thick and that a low quality substrate must be thin in order to achieve the maximum power generation in the respective materials. The dividing point is 70 μm/5 × 10−6 sec. That is, for materials with a minority carrier recombination lifetime longer than 5 × 10−6 sec, the substrate must be thicker than 70 μm, while for materials with a lifetime shorter than 5 × 10−6 sec, the substrate must be thinner than 70 μm. In substrate fabrication, the thinner the wafer, the lower the cost of material, but the higher the cost of wafer fabrication. Thus, the optimum thickness/lifetime combinations are defined in this study along with the substrate cost considerations as part of the factors to be considered in material selection.