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The modern resurgence of the common (Cimex lectulariusL.) and tropical bed bugs (C. hemipterus[F.]) is thought to be primarily due to insecticide resistance. While there are many reports on insecticide resistance mechanisms in C. lectularius, such information in C. hemipterusis limited. We examined dichloro-diphenyl-trichloroethane (DDT), malathion, deltamethrin, permethrin, lambda-cyhalothrin resistance, and the underlying mechanisms in several C. hemipterusstrains (Australia: Queensland [QLD-AU]; Malaysia: Kuala Lumpur [KL-MY], Tanjung Tokong [TT-MY], Christian [CH-MY], and Green Lane [GL-MY]). We used a surface contact method, synergism studies (utilizing piperonyl butoxide [PBO], S,S,S-tributyl phosphorotrithioate [DEF], and diethyl maleate [DEM]), and molecular detection of kdrmutations. Results demonstrated that all C. hemipterusstrains possessed high resistance to DDT and the pyrethroids and moderate to high resistance to malathion. Synergism studies showed that deltamethrin resistance in all strains was significantly (P< 0.05) inhibited by PBO. In contrast, deltamethrin resistance was not affected in DEF or DEM. Similar findings were found with lambda-cyhalothrin resistance. Malathion resistance was significantly (P< 0.05) reduced by DEF in all strains. Resistance to DDT was not affected by DEM in all strains. Multiple kdrmutations (M918I, D953G, and L1014F) were detected by molecular analyses. TT-MY strain was found with individuals possessing three kdrmutation combinations; D953G + L1014F (homozygous susceptible: M918), M918I + D953G + L1014F (heterozygous resistant: I918), and M918I + D953G + L1014F (homozygous resistant: I918). Individuals with M918I + D953G + L1014F (homozygous resistant: I918) survived longer on deltamethrin (>12 h) than those (≤1 h) with other combinations. M918I + L1014F mutations most likely conferred super-kdrcharacteristic toward pyrethroids and DDT in C. hemipterus.

This study examined the presence of insecticide resistance in different developmental stages (adults, first instars, and eggs) of the tropical bed bug, Cimex hemipterus(F.) using several insecticide formulations. Adults and first instars of five strains (Queensland, Kuala Lumpur, Bukit Mertajam, Saujana, and Krystal Point) were evaluated using the surface contact method and compared with a susceptible strain (Monheim) of the common bed bug Cimex lectulariusL. The insecticide formulations were used at their label rates in this study: Tandem (thiamethoxam [11.6%], lambda-cyhalothrin [3.5%]) at 183.96 mg/m2; Temprid SC (imidacloprid [21%], beta-cyfluthrin [10.5%]) at 106.13 mg/m2; Sumithion 20CS (fenitrothion [20%]) at 250 mg/m2; Pesguard FG161 (d-tetramethrin [4.4%], cyphenothrin [13.2%]) at 110 mg/m2; and Sumithrin 10SEC (d-phenothrin [10%]) at 100 mg/m2. Results showed a very high level of resistance to Pesguard FG161 (388.3 to >605.0 times) and Sumithrin (302.9 to >365.5 times) in all adults of the strains tested, whereas low to high levels of resistance were registered for Tandem (1.4–4.7 times), Temprid (7.3–16.7 times), and Sumithion (1.2–14.6 times) for adults of all bed bug strains. For first instars, resistance to the former two formulations were high to very high (31.4–118.1 times). In contrast, they showed lower resistance to Tandem, Temprid, and Sumithion (1.0–10.2 times). An immersion method used to test on bed bug eggs found high to very high resistance toward all tested formulations. Results demonstrate that the resistance level varies between bed bug developmental stages.

With the development of micro-nanomachining technology (MNMT), micro heat radiator is getting attention. In this paper, the heat dissipation mechanism of light emitting diode (LED) ball lamp is introduced. And the LED heat radiator is simplified. On the basis of that, a new type of micro metal-plastic heat radiator of LED is put forward. And the LED heat radiator is simplified. A series of numerical simulations are carried out to compare the heat dissipation performance of micro heat radiator respectively made by metal, plastic, metal-plastic composite by the FloEFD software. Micro metal-plastic heat radiator structures, including fin spacing, fin thickness, fin height and substrate thickness, are carry out to be simulated.

The TiC/Fe-based composite coating was fabricated by plasma transferred arc (PTA) weld-surfacing process on substrate of Q235 steel with the mixture of ferrotitanium, ferrochromium and ferrosilicium powders. The microstructure and wear properties of the coating were investigated by means of X-ray diffraction (XRD), scanning electron micrograph (SEM), energy dispersive X-ray analysis (EDS), microhardness test and wear test. The results show that the coating consists of TiC, (Cr,Fe)7C3 and austenite. The composite coating is metallurgically bonded to the Q235 steel substrate. TiC particles formed by PTA weld-surfacing process presented cubic or “dendrite flower-like” morphology. The wear-resisting property of the coating was greatly improved compared with the substrate. The coating has excellent adhesive wear and grinding abrasion resisting force.

The characteristics of several package structures of high power white Light emitting diode (LED) are described in this paper. The influence of different structures on thermal properties is analyzed. Forward voltage method is used to test the thermal resistance of LED chips.

A new type of plastic micro heat radiators is designed in this paper. The radiator is prospected to be used in electronic system, chemical engineering system, etc. It is made of modified Phenylene sulfide with high thermal conductivity. A series of numerical simulations are carried out to optimize the structure of the radiator. The structure of the radiator includes the thickness of the fin and the distance between fins. The results show that the performance of the micro plastic heat radiator is very close to that of the metal heat radiator with the same dimension.

We previously showed that different skeletal muscles in Daurian ground squirrels (Spermophilus dauricus) possess different antioxidant strategies during hibernation; however, the reason for these varied strategies remains unclear. To clarify this issue, we studied REDD1, FOXO4, PGC-1α, FOXO1 and atrogin-1 proteins to determine the potential cause of the different antioxidant strategies in Daurian ground squirrels during hibernation, and to clarify whether different strategies affect atrophy-related signals. Results showed that the soleus (SOL) muscle experienced intracellular hypoxia during interbout arousal, but no oxidative stress. This may be due to increased PGC-1α expression enhancing antioxidant capacity in the SOL under hypoxic conditions. Extensor digitorum longus (EDL) muscle showed no change in oxidative stress, hypoxia or antioxidant capacity during hibernation. The FOXO1 and PGC-1α results strongly suggested differentially regulated fuel metabolism in the SOL and EDL muscles during hibernation, i.e. enhanced lipid oxidation and maintained anaerobic glycolysis, respectively. Atrogin-1 expression did not increase during hibernation in either the SOL or EDL, indicating that protein synthesis was not inhibited by atrogin-1. Thus, our results suggest that different fuel regulation may be one mechanism related to antioxidant defense strategy formation in different kinds of skeletal muscle fibers of Daurian ground squirrels during hibernation.

Osteoporosis has become the biggest cause of non-fatal health issue. Currently, the limitations of traditional anti-osteoporosis drugs such as long-term ill-effects and drug resistance, have raised concerns toward complementary and alternative therapies, particularly herbal medicines and their natural active compounds. Thus, this study aimed to provide an integrative analysis of active chemicals, drug targets and interacting pathways of the herbs for osteoporosis treatment.

Resistance to insecticides, especially the pyrethroids, in the common bed bug, Cimex lectularius L., has been well-documented. However, the presence and relative contribution of metabolic detoxifying microsomal oxidases and hydrolytic esterases to the observed resistance has yet to be fully elucidated. This is due, in part, to the absence of a simple bioassay procedure that appropriately isolates esterases from potentially competing oxidases. Recently, an analogue of piperonyl butoxide (PBO) was developed, EN16/5-1 (6-[2-(2-butoxyethoxy)ethoxymethyl]-5-propyl-2,3-dihydrobenzofuranby), which inhibits esterases but has limited efficacy against the oxidases, whereas PBO inhibits both. The opportunity is now available to use both synergists via established bioassay methodologies and to screen for the potential presence of oxidase- or esterase-derived pyrethroid resistance in insecticide-resistant insects, including bed bugs. In the present study, EN16/5-1 and PBO were assayed in conjunction with deltamethrin against four field strains of C. lectularius collected from independent geographic locations across Australia. All strains expressed a high degree of resistance to deltamethrin and significant inhibition of the observed resistance with preexposure to PBO. Nonsignificant differences between the cumulative mortality values for PBO and EN16/5-1 were then observed in two of the four bed bug strains, which indicate that detoxifying esterases are conferring substantially to the observed resistance in those strains. This study is the first to provide evidence that metabolic detoxification in the form of both hydrolytic esterases and microsomal oxidases is a major contributing factor to pyrethroid resistance in C. lectularius.