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Background Calcineurin B-like proteins (CBLs) are major Ca2+ sensors that interact with CBL-interacting protein kinases (CIPKs) to regulate growth and development in plants. The CBL-CIPK network is involved in stress response, yet little is understood on how CBL-CIPK function in pepper (Capsicum annuum L.), a staple vegetable crop that is threatened by biotic and abiotic stressors. Results In the present study, nine CaCBL and 26 CaCIPK genes were identified in pepper and the genes were named based on their chromosomal order. Phylogenetic and structural analysis revealed that CaCBL and CaCIPK genes clustered in four and five groups, respectively. Quantitative real-time PCR (qRT-PCR) assays showed that CaCBL and CaCIPK genes were constitutively expressed in different tissues, and their expression patterns were altered when the plant was exposed to Phytophthora capsici, salt and osmotic stress. CaCIPK1 expression changed in response to stress, including exposure to P. capsici, NaCl, mannitol, salicylic acid (SA), methyl jasmonate (MeJA), abscisic acid (ABA), ethylene (ETH), cold and heat stress. Knocking down CaCIPK1 expression increased the susceptibility of pepper to P. capsici, reduced root activity, and altered the expression of defense related genes. Transient overexpression of CaCIPK1 enhanced H2O2 accumulation, cell death, and expression of genes involved in defense. Conclusions Nine CaCBL and 26 CaCIPK genes were identified in the pepper genome, and the expression of most CaCBL and CaCIPK genes were altered when the plant was exposed to stress. In particular, we found that CaCIPK1 is mediates the pepper plant’s defense against P. capsici. These results provide the groundwork for further functional characterization of CaCBL and CaCIPK genes in pepper.

Anthracnose caused by Colletotrichum acutatum is one of the most devastating fungal diseases of pepper (Capsicum annuum L.). The utilization of chitin-binding proteins or chitinase genes is the best option to control this disease. A chitin-binding domain (CBD) has been shown to be crucial for the innate immunity of plants and activates the hypersensitive response (HR). The CaChiIII7 chitinase gene has been identified and isolated from pepper plants. CaChiIII7 has repeated CBDs that encode a chitinase enzyme that is transcriptionally stimulated by C. acutatum infection. The knockdown of CaChiIII7 in pepper plants confers increased hypersensitivity to C. acutatum, resulting in its proliferation in infected leaves and an attenuation of the defense response genes CaPR1, CaPR5, and SAR8.2 in the CaChiIII7-silenced pepper plants. Additionally, H2O2 accumulation, conductivity, proline biosynthesis, and root activity were distinctly reduced in CaChiIII7-silenced plants. Subcellular localization analyses indicated that the CaChiIII7 protein is located in the plasma membrane and cytoplasm of plant cells. The transient expression of CaChiIII7 increases the basal resistance to C. acutatum by significantly expressing several defense response genes and the HR in pepper leaves, accompanied by an induction of H2O2 biosynthesis. These findings demonstrate that CaChiIII7 plays a prominent role in plant defense in response to pathogen infection.

Background: There are few studies on the relative factors related to postoperative recurrence. Objectives: To compare the outcomes of pelvic floor reconstruction involving Herniamesh mesh and biological grafts and to investigate the correlative factors of postoperative recurrence. Method: Two hundred and thirty-two patients were randomly divided into 2 groups: Herniamesh mesh group (117) and biological graft group (115). Follow-ups for 6 months and 1 year after the surgery. The primary outcomes were recurrence, perioperative complications. Secondary outcome was a questionnaire about the life habits associated with relapse. Results: The recurrence rate at 6 months or 1 year did not differ substantially between the 2 groups (p = 0.787 and 0.968, respectively). Adverse events occurred with significantly different frequencies over 1 year (p = 0.005). Twelve factors were investigated and analyzed by logistic regression analysis. It showed that recurrence had a strong association with a long-term vegetarian diet (OR 0.283, 95% CI 0.117–0.683), long-term soybean product diet (OR 8.010, 95% CI 2.514–25.523), and vaginal intercourse (OR 5.154, 95% CI 1.461–18.184). Conclusions: The surgical recurrence rate for the mesh was similar to biological grafts at short-term follow-up. Eating soy products often and vaginal intercourse after surgery can reduce recurrence.

Objective To inquire into the influence of the pelvic floor reconstruction surgery of pelvic organ prolapse on Papillomavirus-Negative atypical squamous cells of undetermined significance cytology. Methods This investigation was studied retrospectively about female patients of POP 3~4 stage with high-risk human papillomavirus DNA-negative ASCUS between January, 2008 and September, 2018.All patients received one of two treatment regimens, pelvic floor reconstruction or local hydrocortisone cream(0.1% Hydrocortisone Butyrate cream, 1g nightly for no less than 12 weeks). After 6 months follow-up, we collected data to compare the positive rate of ASCUS with high-risk human papillomavirus DNA-negative between the two groups after intervention. Results The negative conversion rate of ASCUS in the operative patients was higher than in patients using local hydrocortisone cream (33/47 [70.2%] vs 19/44 [43.2%], P = 0.009). Conclusions The decline of non–human papillomavirus ASCUS cytology in postoperative patients might be related to pelvic floor reconstruction.

Little information is available on the role of Squamosa promoter binding protein (SBP)-box genes in pepper plants. This family of genes is known to have transcription characteristics specific to plants and to regulate plant growth, development, stress responses, and signal transduction. To investigate their specific effects in pepper (Capsicum annuum), we screened pepper SBP-box family genes (CaSBP genes) for Phytophthora capsici (P. capsici) resistance genes using virus-induced gene silencing. CaSBP08, CaSBP11, CaSBP12, and CaSBP13, which are associated with plant defense responses against P. capsici, were obtained from among fifteen identified CaSBP genes. The function of CaSBP08 was identified in pepper defense response against P. capsici infection in particular. CaSBP08 protein was localized to the nucleus. Silencing of CaSBP08 enhanced resistance to P. capsici infection. Following P. capsici inoculation, the malondialdehyde content, peroxidase activity, and disease index percentage of the CaSBP08-silenced plants decreased compared to the control. Additionally, the expression levels of other defense-related genes, especially those of CaBPR1 and CaSAR8.2, were more strongly induced in CaSBP08-silenced plants than in the control. However, CaSBP08 overexpression in Nicotiana benthamiana enhanced susceptibility to P. capsici infection. This work provides a foundation for the further research on the role of CaSBP genes in plant defense responses against P. capsici infection.

The AP2/ERF family is one of the largest transcription factor families in the plant kingdom. AP2/ERF genes contributing to various processes including plant growth, development, and response to various stresses have been identified. In this study, 175 putative AP2/ERF genes were identified in the latest pepper genome database and classified into AP2, RAV, ERF, and Soloist subfamilies. Their chromosomal localization, gene structure, conserved motif, cis-acting elements within the promoter region, and subcellular locations were analyzed. Transient expression of CaAP2/ERF proteins in tobacco revealed that CaAP2/ERF064, CaAP2/ERF109, and CaAP2/ERF127 were located in the nucleus, while CaAP2/ERF171 was located in the nucleus and cytoplasm. Most of the CaAP2/ERF genes contained cis-elements within their promoter regions that responded to various stresses (HSE, LTR, MBS, Box-W1/W-box, and TC-rich repeats) and phytohormones (ABRE, CGTCA-motif, and TCA-element). Furthermore, RNA-seq analysis revealed that CaAP2/ERF genes showed differential expression profiles in various tissues as well as under biotic stresses. Moreover, qRT-PCR analysis of eight selected CaAP2/ERF genes also showed differential expression patterns in response to infection with Phytophthora capsici (HX-9) and in response to phytohormones (SA, MeJA, and ETH). This study will provide basic insights for further studies of the CaAP2/ERF genes involved in the interaction between pepper and P. capsici.

SBP-box (Squamosa-promoter binding protein) genes are a type of plant-specific transcription factor and play important roles in plant growth, signal transduction, and stress response. However, little is known about the role of pepper SBP-box transcription factor genes in response to abiotic stress. Here, one of the pepper SBP-box gene, CaSBP12, was selected and isolated from pepper genome database in our previous study. The CaSBP12 gene was induced under salt stress. Silencing the CaSBP12 gene enhanced pepper plant tolerance to salt stress. The accumulation of reactive oxygen species (ROS) of the detached leaves of CaSBP12-silenced plants was significantly lower than that of control plants. Besides, the Na+, malondialdehyde content, and conductivity were significantly increased in control plants than that in the CaSBP12-silenced plants. In addition, the CaSBP12 over-expressed Nicotiana benthamiana plants were more susceptible to salt stress with higher damage severity index percentage and accumulation of ROS as compared to the wild-type. These results indicated that CaSBP12 negatively regulates salt stress tolerance in pepper may relate to ROS signaling cascades.

Little information is available on the role of Squamosa promoter binding protein (SBP)-box genes in pepper plants. This family of genes is known to have transcription characteristics specific to plants and to regulate plant growth, development, stress responses, and signal transduction. To investigate their specific effects in pepper (Capsicum annuum), we screened pepper SBP-box family genes (CaSBP genes) for Phytophthora capsici (P. capsici) resistance genes using virus-induced gene silencing. CaSBP08, CaSBP11, CaSBP12, and CaSBP13, which are associated with plant defense responses against P. capsici, were obtained from among fifteen identified CaSBP genes. The function of CaSBP08 was identified in pepper defense response against P. capsici infection in particular. CaSBP08 protein was localized to the nucleus. Silencing of CaSBP08 enhanced resistance to P. capsici infection. Following P. capsici inoculation, the malondialdehyde content, peroxidase activity, and disease index percentage of the CaSBP08-silenced plants decreased compared to the control. Additionally, the expression levels of other defense-related genes, especially those of CaBPR1 and CaSAR8.2, were more strongly induced in CaSBP08-silenced plants than in the control. However, CaSBP08 overexpression in Nicotiana benthamiana enhanced susceptibility to P. capsici infection. This work provides a foundation for the further research on the role of CaSBP genes in plant defense responses against P. capsici infection.

The basic leucine zipper (bZIP) proteins compose a family of transcription factors (TFs), which play a crucial role in plant growth, development, and abiotic and biotic stress responses. However, no comprehensive analysis of bZIP family has been reported in pepper (Capsicum annuum L.). In this study, we identified and characterized 60 bZIP TF-encoding genes from two pepper genomes. These genes were divided into 10 groups based on their phylogenetic relationships with bZIP genes from Arabidopsis. Six introns/exons structural patterns within the basic and hinge regions and the conserved motifs were identified among all the pepper bZIP proteins, on the basis of which, we classify them into different subfamilies. Based on the transcriptomic data of Zunla-1 genome, expression analyses of 59 pepper bZIP genes (not including CabZIP25 of CM334 genome), indicated that the pepper bZIP genes were differentially expressed in the pepper tissues and developmental stages, and many of the pepper bZIP genes might be involved in responses to various abiotic stresses and phytohormones. Further, gene expression analysis, using quantitative real-time PCR (qRT-PCR), showed that the CabZIP25 gene was expressed at relatively higher levels in vegetative tissues, and was strongly induced by abiotic stresses and phytohormones. In comparing with wild type Arabidopsis, germination rate, fresh weight, chlorophyll content, and root lengths increased in the CabZIP25-overexpressing Arabidopsis under salt stress. Additionally, CabZIP25-silenced pepper showed lower chlorophyll content than the control plants under salt stress. These results suggested that CabZIP25 improved salt tolerance in plants. Taken together, our results provide new opportunities for the functional characterization of bZIP TFs in pepper.

Due to the present scenario of climate change, plants have to evolve strategies to survive and perform under a plethora of biotic and abiotic stresses, which restrict plant productivity. Maintenance of plant protein functional conformation and preventing non-native proteins from aggregation, which leads to metabolic disruption, are of prime importance. Plant heat shock proteins (HSPs), as chaperones, play a pivotal role in conferring biotic and abiotic stress tolerance. Moreover, HSP also enhances membrane stability and detoxifies the reactive oxygen species (ROS) by positively regulating the antioxidant enzymes system. Additionally, it uses ROS as a signal to molecules to induce HSP production. HSP also enhances plant immunity by the accumulation and stability of pathogenesis-related (PR) proteins under various biotic stresses. Thus, to unravel the entire plant defense system, the role of HSPs are discussed with a special focus on plant response to biotic and abiotic stresses, which will be helpful in the development of stress tolerance in plant crops.

The Broad-complex Tramtrack and Bric-a-brac (BTB) domain participates in plant responses to biotic and abiotic stresses, however its role is unknown in pepper plants. CaBPM4 has meprin and TRAF homology (MATH) and BTB domains at its N- and C-termini, respectively, and it contains a 1589-bp full-length cDNA that encodes a protein containing 403 amino acids. In this study, the pepper gene CaBPM4 (Capsicum annuum BTB-POZ and MATH domain protein) was cloned, and its role in responses to Phytophthora capsici, cold, drought, and salt stress were characterized. The results of quantitative RT-PCR revealed that CaBPM4 was down-regulated under P. capsici infection, salicylic acid, H2O2, and abscisic acid treatments, while abiotic stresses, including salt, cold, and drought, enhanced its transcript level. Furthermore, CaBPM4 silencing significantly impaired resistance to P. capsici, apparently by altering the transcript level of defense-related genes CaPR1, CaDEF1, and CaSAR82 and reducing root activity. However, CaBPM4-silenced plants exhibited remarkably increased peroxidase activity and decreased malondialdehyde concentrations, indicating that CaBPM4 may enhance resistance to salt and drought stress. Further study should focus on the mechanism by which CaBPM4 regulates the defense response to P. capsici infection and abiotic stresses.

HSP60 gene family in pepper was analyzed through bioinformatics along with transcriptional regulation against multiple abiotic and hormonal stresses. Furthermore, the knockdown of CaHSP60-6 increased sensitivity to heat stress. The 60 kDa heat shock protein (HSP60) also known as chaperonin (cpn60) is encoded by multi-gene family that plays an important role in plant growth, development and in stress response as a molecular chaperone. However, little is known about the HSP60 gene family in pepper (Capsicum annuum L.). In this study, 16 putative pepper HSP60 genes were identified through bioinformatic tools. The phylogenetic tree revealed that eight of the pepper HSP60 genes (50%) clustered into group I, three (19%) into group II, and five (31%) into group III. Twelve (75%) CaHSP60 genes have more than 10 introns, while only a single gene contained no introns. Chromosomal mapping revealed that the tandem and segmental duplication events occurred in the process of evolution. Gene ontology enrichment analysis predicted that CaHSP60 genes were responsible for protein folding and refolding in an ATP-dependent manner in response to various stresses in the biological processes category. Multiple stress-related cis-regulatory elements were found in the promoter region of these CaHSP60 genes, which indicated that these genes were regulated in response to multiple stresses. Tissue-specific expression was studied under normal conditions and induced under 2 h of heat stress measured by RNA-Seq data and qRT-PCR in different tissues (roots, stems, leaves, and flowers). The data implied that HSP60 genes play a crucial role in pepper growth, development, and stress responses. Fifteen (93%) CaHSP60 genes were induced in both, thermo-sensitive B6 and thermo-tolerant R9 lines under heat treatment. The relative expression of nine representative CaHSP60 genes in response to other abiotic stresses (cold, NaCl, and mannitol) and hormonal applications [ABA, methyl jasmonate (MeJA), and salicylic acid (SA)] was also evaluated. Knockdown of CaHSP60-6 increased the sensitivity to heat shock treatment as documented by a higher relative electrolyte leakage, lipid peroxidation, and reactive oxygen species accumulation in silenced pepper plants along with a substantial lower chlorophyll content and antioxidant enzyme activity. These results suggested that HSP60 might act as a positive regulator in pepper defense against heat and other abiotic stresses. Our results provide a basis for further functional analysis of HSP60 genes in pepper.

Phytophthora blight is one of the most destructive diseases of pepper (Capsicum annuum L.) globally. The APETALA2/Ethylene Responsive Factors (AP2/ERF) genes play a crucial role in plant response to biotic stresses but, to date, have not been studied in the context of Phytophthora resistance in pepper. Here, we documented potential roles for the pepper CaAP2/ERF064 gene in inducing cell death and conferring resistance to Phytophthora capsici (P. capsici) infection. Results revealed that the N-terminal, AP2 domain, and C-terminal of CaAP2/ERF064 protein is responsible for triggering cell death in Nicotiana benthamiana (N. benthamiana). Moreover, the transcription of CaAP2/ERF064 in plant is synergistically regulated by the Methyl-Jasmonate (MeJA) and ethephon (ET) signaling pathway. CaAP2/ERF064 was found to regulate the expression of CaBPR1, which is a pathogenesis-related (PR) gene of pepper. Furthermore, the silencing of CaAP2/ERF064 compromised the pepper plant resistance to P. capsici by reducing the transcript level of defense-related genes CaBPR1, CaPO2, and CaSAR82, while the ectopic expression of CaAP2/ERF064 in N. benthamiana plant elevated the expression level of NbPR1b and enhanced resistance to P. capsici. These results suggest that CaAP2/ERF064 could positively regulate the defense response against P. capsici by modulating the transcription of PR genes in the plant.

Anthracnose caused by Colletotrichum acutatum is one of the most devastating fungal diseases of pepper (Capsicum annuum L.). The utilization of chitin-binding proteins or chitinase genes is the best option to control this disease. A chitin-binding domain (CBD) has been shown to be crucial for the innate immunity of plants and activates the hypersensitive response (HR). The CaChiIII7 chitinase gene has been identified and isolated from pepper plants. CaChiIII7 has repeated CBDs that encode a chitinase enzyme that is transcriptionally stimulated by C. acutatum infection. The knockdown of CaChiIII7 in pepper plants confers increased hypersensitivity to C. acutatum, resulting in its proliferation in infected leaves and an attenuation of the defense response genes CaPR1, CaPR5, and SAR8.2 in the CaChiIII7-silenced pepper plants. Additionally, H2O2 accumulation, conductivity, proline biosynthesis, and root activity were distinctly reduced in CaChiIII7-silenced plants. Subcellular localization analyses indicated that the CaChiIII7 protein is located in the plasma membrane and cytoplasm of plant cells. The transient expression of CaChiIII7 increases the basal resistance to C. acutatum by significantly expressing several defense response genes and the HR in pepper leaves, accompanied by an induction of H2O2 biosynthesis. These findings demonstrate that CaChiIII7 plays a prominent role in plant defense in response to pathogen infection.

Wang, H. and Wei, A.-M., 2020. Talent demand and training strategy of oceangoing cruise company based on customized talent development model. In: Gong, D.; Zhang, M., and Liu, R. (eds.), Advances in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 106, pp. 233–236. Coconut Creek (Florida), ISSN 0749-0208.With the rapid development of China's national economy and foreign trade, the oceangoing cruise industry has had huge development potential in China, with a corresponding requirement for cruise talent. However, the gap in talent from international cruise companies has seriously affected the development needs of domestic companies. Based on a customized talent development model, this paper studies the talent demand of ocean cruise companies and seeks high-quality talent training strategies for ocean cruise companies. The research results show that there exist many problems in China's cruise talent training in terms of different levels, categories, and contents; the training of customized talent in China includes internal training, intermediary training, and college education training; the strategies of training marine talent need to be carried out from the system level, the process level, and the environmental level. The research findings provide a theoretical basis for talent training in the marine system.

Environmental stress affects growth and development of crops, and reduces yield and quality of crops. To cope with environmental stressors, plants have sophisticated defense mechanisms, including the HSF/HSP pathway. Here, we identify the expression pattern of CaHSP16.4 in thermo-tolerant and thermo-sensitive pepper (Capsicum annuum L.) lines. Under heat stress, R9 thermo-tolerant line had higher CaHSP16.4 expression level than the B6 thermo-sensitive line. Under drought stress, expression pattern of CaHSP16.4 was dynamic. Initially, CaHSP16.4 was downregulated then CaHSP16.4 significantly increased. Subcellular localization assay showed that CaHSP16.4 localizes in cytoplasm and nucleus. In the R9 line, silencing of CaHSP16.4 resulted in a significant increase in malonaldehyde content and a significant reduction in total chlorophyll content, suggesting that silencing of CaHSP16.4 reduces heat and drought stresses tolerance. Overexpression of CaHSP16.4 enhances tolerance to heat stress in Arabidopsis. Under heat stress, the survival rate of CaHSP16.4 overexpression lines was significantly higher than wild type. Furthermore, under heat, drought, and combined stress conditions, the CaHSP16.4-overexpression lines had lower relative electrolytic leakage and malonaldehyde content, higher total chlorophyll content, and higher activity levels of superoxide dismutase, catalase, ascorbic acid peroxidase, and glutathione peroxidase compared to wild type. Furthermore, the expression levels of the stress response genes in the overexpression lines were higher than the wild type. These results indicate that the overexpression of CaHSP16.4 enhances the ability of reactive oxygen species scavenging under heat and drought stress.

Histone deacetylase (HDAC) 4 is an emerging target in cancer therapeutics, but little is known about the function of HDAC4 in gynecologic malignancies. Therefore we investigated the mechanism of HDAC4 promoting the proliferation of epithelial ovarian cancer cells (OV). In this study, we observed that the proliferation of cells with HDAC4 inhibitor Trichostatin A (TSA) treatment was markedly decreased, Further, we showed that epithelial ovarian cancer tissues with stage III/IV had higher HDAC4 expression, compared to that with stage I/II. We examined first that the HDAC4 expression was increased in response to fibrillar collagen matrices. In addition, we found that HDAC4 was retained in the nucleus by regulation of PP1α, which regulated HDAC4 cellular fraction via phosphorylation of HDAC4. In addition, we found that HDAC4 bound to Sp1 in epithelial ovarian cancer cells. Finally, ovarian cancer cell line OVCAR3 was evaluated via gain/loss-of-function of HDAC4 by either overexpression of HDCA4 or knock-down of HDAC4 with shRNA. We examined both protein and mRNA of p21 by western blotting and qPCR. We performed analysis of colony formation in matrigel and migration by ECIS. Our results suggest that the accumulation of HDAC4 induced by fibrillar collagen matrices in the nucleus via co-localization of PP1α, leads to repression of the mRNA/protein of p21 and in turn promotes the proliferation and migration of epithelial ovarian cancer cells.

This research applied the Likert-type scale to design the questionnaire. Then, we did research on the professionals in the field of construction in Guangdong province, which aimed to know about the effect and position of the Guangdong province local standard in engineering construction quality assurance. The statistic analysis shows that there are 73 items of existing Guangdong province engineering construction local standard. Among them, 28.10% takes the local standard as the common basis in engineering construction. While, the national standard is 38.08%; the industry rule is 29.20%. The three almost is in the same position. The whole industry thinks that the local standard has the equivalent status and effect as the national standard and industry rule in the engineering construction. Therefore, it is necessary to suggest the government sector to perfect the basis of the establishment of engineering construction local standard. In this way, it can be ensured that the procedure is open and transparent, the standard is formulated according to development of the productive force and the implementation process can be supervised by the public. What’s more, we can formulate the local standard with local features according to the region’s real need and local natural conditions. So, the effects of Guangdong province local standard can be played more efficiently in the engineering construction quality assurance.

Phytophthora blight is one of the most destructive diseases of pepper (Capsicum annuum L.) globally. The APETALA2/Ethylene Responsive Factors (AP2/ERF) genes play a crucial role in plant response to biotic stresses but, to date, have not been studied in the context of Phytophthora resistance in pepper. Here, we documented potential roles for the pepper CaAP2/ERF064 gene in inducing cell death and conferring resistance to Phytophthora capsici (P. capsici) infection. Results revealed that the N-terminal, AP2 domain, and C-terminal of CaAP2/ERF064 protein is responsible for triggering cell death in Nicotiana benthamiana (N. benthamiana). Moreover, the transcription of CaAP2/ERF064 in plant is synergistically regulated by the Methyl-Jasmonate (MeJA) and ethephon (ET) signaling pathway. CaAP2/ERF064 was found to regulate the expression of CaBPR1, which is a pathogenesis-related (PR) gene of pepper. Furthermore, the silencing of CaAP2/ERF064 compromised the pepper plant resistance to P. capsici by reducing the transcript level of defense-related genes CaBPR1, CaPO2, and CaSAR82, while the ectopic expression of CaAP2/ERF064 in N. benthamiana plant elevated the expression level of NbPR1b and enhanced resistance to P. capsici. These results suggest that CaAP2/ERF064 could positively regulate the defense response against P. capsici by modulating the transcription of PR genes in the plant.

A rapid and efficient method has been developed for the synthesis of azo aromatic diacyl chlorides from nitro aromatic acids by using dimethyl benzene as solvent. The products are obtained in good yields with high purity.

Continuous weld pool images of 6 mm aluminum alloy from rear and side directions in twin arc welding were successfully obtained with a near-infrared filter and a neutral density filter at an exposure time shorter than pulse period. A modified Snake active contour model for weld pool contour extraction was proposed and the contours of the two directional weld pool images were extracted accurately. Through analyzing the two directional continuous weld pool images it was found that the average geometric feature of continuous multi frame images of weld pools other than one single image can reflect the actual welding process.

To investigate the injury effects of microwave on the visual performance and the apoptosis of retinal ganglion cells (RGCs) in rats and the relationship between the impaired visual performance and RGCs apoptosis induced by microwave.The visual performance of rats was observed by Electroretinogram (ERG) and Flash visual evoked potentials (F-VEP). The apoptosis of RGCs in vivo and in vitro was detected by TUNEL assay and Hoechst staining.Microwave exposure had no influence on ERG-a wave. The amplitude of ERG-b wave decreased significantly on the 3rd day and 7th day after microwave exposure (P0.01).The latency of ERG-b wave shortened significantly only at 3rd day after microwave exposure (P0.01). The latency of F-VEP extended markedly on the 3rd day after exposure (P0.05) and recovered on the 7th day after microwave exposure. The amplitude of F-VEP decreased significantly in exposure group, as compared with sham-exposure group, on the 3rd day and 7th day after microwave exposure (P0.05). After microwave exposure for 12 h, the apoptotic rate of RGCs in rat increased from 2.85% to 6.73%, and on the 7th day after exposure, the apoptotic rate of RGCs remained 8.93% (P0.05). The apoptotic rate of cultured RGCs increased from 8.42% to 13.91% at 6 hour (P0.05) and to 24.14% at 24 hour (P0.01) after microwave exposure (P0.05 or P0.01).Microwave exposure can injure the visual performance of rats, and the apoptosis of RGCs induced microwave may be one of the main pathological mechanisms.

To investigate the effects of microwave irradiation on the expression and regulation of heat shock proteins (HSPs) in primary cultured rat hippocampal neurons.Neurons were exposed to 90 mW/cm(2) microwave irradiation for 10 minutes. Western blot was used to determine the expression of HSP27, HSP70, HSP90 and heat shock factor 1 (HSF1) at 0, 3, 6, 12 and 24 hour respectively. Real-time RT-PCR was used to determine the mRNA expression of HSF1. DNA-binding activity of HSF1 was measured by electrophoretic mobility shift assay (EMSA).The protein expression of HSP27 was significantly increased by 22%, 36%, 18% at 3, 6, 12 h, respectively (P0.05). The protein expression of HSP70 was significantly increased by 23%, 32%, 26% at 3, 6, 12 h, respectively (P0.05, P0.01). The protein expression of HSP90 was significantly increased by 27%, 33% at 6, 12 h, respectively (P0.05, P0.01). The DNA-binding activity of HSF1 was stimulated, however, no significant change of the expression of HSF1 was observed on both the mRNA and protein levels.The transcriptional activity of HSF1 is activated by microwave irradiation, which promotes the expression of HSPs. Heat shock response which contributes to establish a cytoprotective state is induced by microwave irradiation in primary cultured rat hippocampal neurons.