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Melolonthinae are the largest group of scarab beetles, causing destructive damage to human economy for the larvae attacking a wide variety of crops, pastures and turfs. Rhizotrogina are one of the most specious groups, with their larval taxonomy far from satisfactory. In this study, the larvae of Pseudosymmachia tumidifrons and Brahmina faldermanni were studied through rearing and direct observations using light and scanning electron microscopy. The larvae share the following morphological characters: three pairs clypeal setae, six minute sensilla on haptomerum, and absence of any stridulatory structures on mandibles. The larvae also exhibit distinct morphological differences, such as the number of heli, presence or absence of proplegmatia, size arrangement of spiracles, and the arrangement of palidia on raster. The dramatically morphological differences between these two closely related genera indicate the heterogeneity of the subtribe Rhizotrogina. The morphological and functional diversity of raster were briefly discussed.

Cetoniinae is one of the showiest scarab groups, exhibiting bright-metallic body colors, and usually attract great attention from entomologists and amateur collectors. Larvae of Cetoniinae show dramatically diversity on morphology and living habits. Although being considered one of the best-studied groups of Scarabaeidae, larvae have been described for less than 5% species to the known Cetoniinae. In this study, the final instar larva of Lasiotrichius succinctus hananoi was described using scanning electron microscopy. The larvae are peculiar for bearing a haptomeral process dividing 10 spines into two groups: six on the left side, four on the right side, different from the previous descriptions on L. succinctus (Pallas, 1781). The morphological differences under SEM imply the further requirement of taxonomic revision in Lasiotrichius. Both advantage and disadvantage of SEM utilizing in larval descriptions were briefly discussed.

Melolonthinae are the largest subfamily of Scarabaeidae, considered as serious pests for their larvae attacking plant roots and tubers. The edaphic larvae are difficult to be identified because the study on larval taxonomy is far from satisfactory. In this study, multivoltine white grubs Melolontha incana (Motschulsky, 1853) were investigated using light and scanning electron microscopy, in order to provide more morphological characters for the pest identification. The white grubs are atypical for the epipharynx bearing 14 heli arranged in two rows; the mandible is furnished with a patch of minute granules; the maxilla is equipped with 18 acute stridulatory teeth arranged in line; each femur and tibiotarsus is furnished ventrally with a cluster of fossorial setae. The morphological comparisons with the other melolonthine species were provided. The adaptative relationship between the morphological feature and the multivoltine life history were briefly discussed.

Lucanidae have long received great attention for their adults. However, differentiating between the larvae of stag beetles is difficult and remains unsatisfactorily resolved due to the microscopic features separating groups. In the current study, the larvae of Prismognathus dauricus Motschulsky, 1860 were investigated using light and scanning electron microscopy. The larvae of P. dauricus are atypical for the following characters: i) the epipharynx possesses anteriorly eleven protophoba arranged in a semi-round line; ii) the par stridens consists of 31 ± 0.7 (N = 10) subconical teeth arranged in a slightly curved, longitudinal row; iii) the plectrum is composed of 60 ± 1.4 (N = 10) carinae; iv) the claws of thoracic legs are apically blunt and bear four setae. Moreover, the size arrangement of the larval spiracles also provides valuable taxonomic information. Our SEM study reveals larval ultramorphological characters useful for identification of this species for the first time.

Increased expression of tissue factor (TF) is associated with tumor invasion and metastasis in human colorectal cancer. We have previously observed that TF/FVIIa upregulates matrix metalloproteinase-7 (MMP-7) expression at the transcriptional level in colon cancer cells. MMP-7 overexpression is believed to play an important role in tumor invasion and metastasis. The aim of this study is to elucidate the molecular mechanisms by which TF/FVIIa induced MMP-7 expression and cell invasion in vitro.Reverse transcription polymerase chain reaction, Western blot, luciferase assay, and chromatin immunoprecipitation (ChIP) were used to determine the potential mechanism and signaling pathways by which TF/FVIIa induced MMP-7 expression and cell invasion in LoVo cells. Small interfering RNA (siRNA) and cell invasion assay was used to examine whether blocking c-Fos expression could abolish FVIIa-mediated upregulation of MMP-7 and cell invasion in vitro.The results showed that FVIIa induced the upregulation of MMP-7 both at the mRNA and protein levels in a time- and dose-dependent manner and increased the invasive behavior of LoVo cells. FVIIa enhanced the promoter activity of MMP-7, and the activator protein-1 (AP-1) binding site was responsible for the activation. Site mutation of the AP-1 binding site in the promoter almost completely abolished FVIIa-mediated response. Furthermore, ChIP assay confirmed that FVIIa promoted the direct binding of c-Fos with the MMP-7 promoter in vivo. FVIIa also induced the expression and nuclear accumulation of the AP-1 subunit c-Fos. siRNA-mediated knockdown of c-Fos eliminated FVIIa-stimulated MMP-7 expression and cell migration in vitro. In addition, selective mitogen-activated protein kinase (MAPK) kinase (MEK1/2) inhibitor (PD98059) and p38 MAPK inhibitor SB203580 suppressed MMP-7 upregulation induced by FVIIa.Our data suggest that a novel TF/FVIIa/MAPK/c-Fos/MMP-7 axis plays an important role in modulating the invasion of colon cancer cells and blockage of this pathway holds promise to treat colon cancer metastasis.

To understand mechanical characteristics of frame joints of steel truss SRC beam, the accuracy of the proposed method is proved by the comparison between FEA result and test result, considering different steel ratios, cross flank rods and axial loads as well as plastic model of concrete damage. The result indicates that cross section and steel can delay joint damage and improve the bearing capacity, and that axial load can improve joints shear capacity to some extent but joints ductility is decreased, and that constraint of steel to concrete improves brittleness character caused by bad ductility of concrete.

This article describes a micromachined quartz tuning fork resonator, 6 mm in height by 2 mm in diamter, holding a two-terminal electronic component with a nomial frequency of 36 kHz (at zero degree) and 15 pF typical capacitance packed in a 90 Pa He gas sealed metal container, which has been used as a sensor for temperature measurement with good sensitivity, repeatability and reliability. The temperature sensor is ZYtw-cut-quartz crystal bulk acoustic wave resonator vibrating in a flexural mode. Finite element method is used to analyze the vibratory modes and optimize the structure of the sensor. Design and performance analysis of the quartz tuning fork temperature sensor has been conducted. The sensor prototype was successfully fabricated and calibrated in operation from 0°C to 100°C with sensitivity of 80 ppm/°C.

Blood coagulation factor VII (FVII) is physiologically synthesized in the liver and released into the blood. Binding of FVII to tissue factor (TF) is related to the metastatic potential of tumor cells, also a significant risk factor in the development of hepatic metastasis in patients with colorectal cancer (CRC). It has been found that some cancer cells can produce FVII extrahepatically. However, little is known about FVII and CRC. We therefore hypothesized that CRC cells may synthese FVII, leading to tumor invasion and metastasis.We detected the expression of FVII protein in 55 CRC specimens by immunohistochemical staining. The FVII mRNA in 45 of 55 CRC cases, 6 colon cancer cell lines and one hepatoma cell line was measured by real-time reverse transcription-PCR (RT-PCR). Transwell invasion assays were performed to evaluate the changes of cell migration and invasion of LoVo cancer cells in vitro. We further observed the likely effectors regulated by the TF/FVIIa complex Western blotting assay.Extrahepatic synthesis of FVII was detected in the cytoplasm of 32 (58.2%) CRC specimens by immunohistochemistry, but not in normal mucosa. Liver metastasis (P = 0.003) and TNM staging (P = 0.005) were significantly correlated with FVII antigen expression. The positive ratios in stages I, II, III and IV were 33.3%, 40.0%, 52.4% and 87.5%, respectively. The expression of FVII mRNA in CRC with hepatic metastasis was significantly higher than CRC without hepatic metastasis (5.33 ± 2.88 vs. 1.47 ± 0.51, P = 0.03). Ectopic FVIIa induced a slight increase (1.34-fold) in the number of migrating cells, which was inhibited by the specific TF antibody. The formation of TF/FVIIa complex resulted in a marked increase in the expression of matrix metalloproteinases (MMP)-2 (3.5-fold) and MMP-9 (4.7-fold) in a time-dependent and dose-dependent manner.Extrahepatic synthesis of FVII by CRC cells may promote tumor invasion and metastasis. MMPs, as downstream effectors of TF/FVIIa signaling, facilitate the development of metastasis in colon cancer.