An Application of the Modified Shear Lag Model to Study the Influence of Thermal Residual Stresses on the Stiffness and Yield Strength of Short Fiber Reinforced Metal Matrix Composites

The modified shear lag model proposed recently was applied to calculate thermal residual stresses and subsequent stress distributions under tensile and compressive loadings. The expressions for the elastic moduli and the yield strengths under tensile and compressive loadings were derived which take account of thermal residual stresses. The asymmetries in the elastic modulus and the yield strength were interpreted using the derived expressions and the obtained results of the stress calculations. The model predictions have exhibited good agreements with the experimental results and also with the other theoretical predictions

Characterization of the 19 Novel Cotton FLA Genes and Their Expression Profiling in Fiber Development and in Response to Phytohormones and Salt Stress

Fasciclin-like arabinogalactan proteins(FLAs),a subclass of arabinogalactan proteins(AGPs),are usually involved in cell development in plants.To investigate the expression profiling as well

Susceptible time window and endurable duration of cotton fiber development to high temperature stress

The development of the cotton fiber is very sensitive to temperature variation, and high temperature stress often causes reduced fiber yield and fiber quality. Short-term high temperature stress often occurs during cotton production, but little is known about the specific timing and duration of stress that affects fiber development. To make this clear, pot experiments were carried in 2014 and 2015 in a climate chamber using cotton cultivars HY370WR（less sensitive variety） and Sumian 15（heat sensitive variety）, which present different temperature sensitivities. Changes of the most important fiber quality indices（i.e., fiber length, fiber strength and marcironaire） and three very important fiber development components（i.e., cellulose, sucrose and callose） were analyzed to define the time window and critical duration to the high temperature stress at 34°C（max38°C/min30°C）. When developing bolls were subjected to 5 days of high temperature stress at different days post-anthesis（DPA）, the changes（Δ%） of fiber length, strength and micronire, as a function of imposed time followed square polynomial eq. as y=a＋bx＋cx^2, and the time around 15 DPA was the most sensitive period for fiber quality development in response to heat stress. When 15 DPA bolls were heat-stressed for different durations（2, 3, 4, 5, 6, 7 days）, the changes（Δ%） of fiber length, strength and micronire, as a function of stress duration followed logistic equations y=A_1-A_2/1＋（x/x_0）~p＋A_2. Referred to that 5, 10 and 15% are usually used as criteria to decide whether techniques are effective or changes are significant in crop culture practice and reguard to the fiber quality indices change range, we suggested that 5% changes of the major fiber quality indices（fiber length, fiber strength and micronaire） and 10% changes of fiber development components（cellulose, sucrose and callose） could be taken as criteria to judge whether fiber development and fiber quality have been significantly affected by high temperature stress. The key time window for cotton fiber development in response to the high temperature stress was 13–19 DPA, and the critical duration was about 5 days.

Landslide Monitoring Based on High-Resolution Distributed Fiber Optic Stress Sensor

A landslide monitoring application is presented by using a high-resolution distributed fiber optic stress sensor. The sensor is used to monitor the intra-stress distribution and variations in landslide bodies, and can be used for the early warning of the occurrence of the landslides. The principle of distributed fiber optic stress sensing and the intra-stress monitoring method for landslides are described in detail. By measuring the distributed polarization mode coupling in the polarization-maintaining fiber, the distributed fiber stress sensor with stress measuring range 0 to 15 MPa, spatial resolution 10 cm and measuring range 0.5 km, is designed. The warning system is also investigated experimentally in the field trial.

Ezrin Promotes the Proliferation, Migration, and Invasion of Ovarian Cancer Cells

Objective The underlying mechanism of Ezrin in ovarian cancer(OVCA) is far from being understood.Therefore, this study aimed to assess the role of Ezrin in OVCA cells(SKOV3 and Ca OV3) and investigate the associated molecular mechanisms.Methods We performed Western blotting, reverse transcription-quantitative polymerase chain reaction, MTT, cell colony, cell wound healing, transwell migration and invasion, Rho A and Rac active pull down assays, and confocal immunofluorescence experiments to evaluate the functions and molecular mechanisms of Ezrin overexpression or knockdown in the proliferation and metastasis of OVCA cells.Results The ectopic expression of Ezrin significantly increased cell proliferation, invasiveness, and epithelial–mesenchymal transition(EMT) in OVCA cells. By contrast, the knockdown of endogenous Ezrin prevented OVCA cell proliferation, invasiveness, and EMT. Lastly, we observed that Ezrin can positively regulate the active forms of Rho A rather than Rac-1 in OVCA cells, thereby promoting robust stress fiber formation.Conclusion Our results indicated that Ezrin regulates OVCA cell proliferation and invasiveness by modulating EMT and induces actin stress fiber formation by regulating Rho-GTPase activity, which provides novel insights into the treatment of the OVCA.

Altered cytoskeletal structures in transformed cells exhibiting obviously metastatic capabilities

Oytoskeletal changes in transformed cells (LM-51) exhibiting obviously metastatie eapabilities were investigated by utilization of double-fluorescent labelling through combinations of:(1) tubulin indirect immunofluoresoenoe plus Khodamine-phalloidin staining of F-artins;(2) indirect immunofluorescent staining with α-aotinin polyolonal- and vinoulin monoclonal antibodies. The LM-51 cells which showed metastatic index of >50% were derived from lung metastasis in nude mice after subcutaneous inoculation of human highly metastatic tumor DNA transfected NIH3T3 cell transformants. The parent NIH3T3 cells exhibited well-organized miorotubu-les, prominent stress fibers and adhesion plaques while their transformants showed remarkable oytoskeletal alterations: (1) reduced microtubules but increased MTOC fluorescence; (2) disrupted stress fibers and fewer adhesion plaques with their protein components redistributed in the cytoplasm; (3) F-aotin-and α-actinin/vinculin aggregates appeared in the cytoplasm. These aggregates were dot-like, varied in size (0.1-0.4u,m) and number, located near the ventral surface of the cells. TPA-induced aotin/vinoulin bodies were studied too. Indications that aotin and α-actinin/vinoulin redistribution might be important alterations involved in the expression of metastatio capabilities of LM-51 transformed cells were discussed.

Stress-induced visceral analgesia assessed non-invasively in rats is enhanced by prebiotic diet

AIM: To investigate the influence of repeated water avoidance stress (rWAS) on the visceromotor response (VMR) to colorectal distension (CRD) and the modulation of the response by a prebiotic diet in rats using a novel surgery-free method of solid-state manometry.METHODS: Male Wistar rats fed a standard diet with or without 4% enzyme-treated rice fiber (ERF) for 5 wk were subjected to rWAS (1 h daily x 10 d) or no stress. The VMR to graded phasic CRD was assessed by intraluminal colonic pressure recording on days 0 (base-line), 1 and 10 (45 min) and 11 (24 h) after rWAS and expressed as percentage change from baseline. Cecal content of short chain fatty acids and distal colonic histology were assessed on day 11. RESULTS: WAS on day 1 reduced the VMR to CRD at 40 and 60 mmHg similarly by 28.9% ± 6.6% in both diet groups. On day 10, rWAS-induced reduction of VMR occurred only at 40 mmHg in the standard diet group (36.2% ± 17.8%) while in the ERF group VMR was lowered at 20, 40 and 60 mmHg by 64.9% ± 20.9%, 49.3% ± 11.6% and 38.9% ± 7.3% respectively. The visceral analgesia was still observed on day 11 in ERF-but not in standard diet-fed rats. By contrast the non-stressed groups (standard or ERF diet) exhibited no changes in VMR to CRD. In standard diet-fed rats, rWAS induced mild colonic histological changes that were absent in ERF-fed rats exposed to stress compared to non-stressed rats. The reduction of cecal content of isobutyrate and total butyrate, but not butyrate alone, was correlated with lower visceral pain response. Additionally, ERF diet increased rWAS-induced defecation by 26% and 75% during the first 0-15 min and last 15-60 min, respectively, compared to standard diet, and reduced rats' body weight gain by 1.3 fold independently of their stress status. CONCLUSION: These data provide the first evidence of psychological stress-related visceral analgesia in rats that was enhanced by chronic intake of ERF prebiotic.

Genome-wide identification and characterization of phospholipase C gene family in cotton (Gossypium spp.)

Phospholipase C (PLC) are important regulatory enzymes involved in several lipid and Ca2+-dependent signaling pathways.Previous studies have elucidated the versatile roles of PLC genes in growth, development and stress responses of many plants, however, the systematic analyses of PLC genes in the important fiber-producing plant, cotton, are still deficient. In this study,through genome-wide survey, we identified twelve phosphatidylinositol-specific PLC (PI-PLC) and nine non-specific PLC (NPC) genes in the allotetraploid upland cotton Gossypium hirsutum and nine PI-PLC and six NPC genes in two diploid cotton G. arboretum and G.raimondii, respectively. The PI-PLC and NPC genes of G. hirsutum showed close phylogenetic relationship with their homologous genes in the diploid cottons and Arabidopsis. Segmental and tandem duplication contributed greatly to the formation of the gene family. Expression profiling indicated that few of the PLC genes are constitutely expressed, whereas most of the PLC genes are preferentially expressed in specific tissues and abiotic stress conditions. Promoter analyses further implied that the expression of these PLC genes might be regulated by MYB transcription factors and different phytohormones.These results not only suggest an important role of phospholipase C members in cotton plant development and abiotic stress response but also provide good candidate targets for future molecular breeding of superior cotton cultivars.