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The article has done some research on multiaxial low cycle fatigue life evaluation methods at home and abroad,summarized multiaxial low cycle fatigue life prediction models based on Critical-Plane method and strain path and analyzed the advantages and disadvantages compared with models and applicability. It has been shown that most of the empirical prediction methods could suitable for only one or few materials so far. When they are applied on other materials,the results are usually disappointing. Meanwhile,the multi-axial fatigue failure of materials are very complicated. The current massive research work was mainly done under constant temperature and load while the studies carried out on high temperature,varying temperature and load are few. If taking notch effect,size effect,surface roughness,residual stress into account,the situation would be even more complicated. Current research on multi axis fatigue is interested in establishing life prediction model,To carry out related fatigue test,Little in-depth study of its micro mechanism The multi-axial fatigue is still a problem needing further studies.

The experiment was conducted to investigate the effects of steam explosion on water soluble pentosans mass fraction of wheat bran. The common commercial wheat bran was exploded by steam under the conditions as follows: the ratio of water to material was 20%, 30% and 50%, steam retention time was 30, 60 and 120 s per ratio of water to material, and steam pressure was kept at 2.0 MPa. Mass fractions of water soluble pentosans, total pentosan, neutral detergent fiber, acid detergent fiber and hemicellulose, and thermogravimetric curves were analyzed. The results showed that steam explosion could significantly increase the mass fraction of water soluble pentosans in wheat bran (P<0.05). Under the same steam pressure, water soluble pentosan mass fraction of the treatments through steam explosion could be increased with the lengthening of steam retention time (P<0.05), water soluble pentosan mass fraction under 60 s steam retention time could be increased by 9.0 times (P<0.05), and that under 120 s retention time could be increased by 10.1 times (P<0.05) compared with untreated wheat bran. Compared with untreated bran, steam explosion increased water soluble pentosans mass fraction at different degree with the increase of ratio of water to material (P<0.05), which could be increased by 9.4 times (P<0.05) at 30% ratio of water to material and by 6.5 times at 50% ratio of water to material (P>0.05). The mass fraction of total pentosans could be significantly decreased in wheat bran by steam explosion (P<0.05), and reduced by 62% (P<0.05) under the conditions of 20% water material ratio, 2.0 MPa steam pressure and 120 s steam retention time compared with untreated wheat bran. Considering the extraction efficiency and energy consumption, the better steam explosion conditions for water soluble pentosans were 30% ratio of water to material and steam processing for 60 s when steam pressure was kept at 2.0 MPa, and under these conditions mass fraction of water soluble pentosans could be increased by 10.8 times (from 1.3% to 13.9%), neutral detergent fiber could be decreased by 17.2% (P<0.05), hemicellulose decreased by 26.7% (P<0.05), activation energy of hemicellulose pyrolysis process increased by 21.5%, initial and end temperature were postponed by 19-30 °C, temperature corresponding to maximum weight loss rate took forward by 13°C and maximum weight loss rate reduced by 43%. This study demonstrates that steam explosion can significantly improve the mass fraction of functional active polysaccharides (water soluble pentosan) in wheat bran, which is helpful for deep processing and utilization of wheat bran. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of telmisartan on expression of resistin in serum and liver under conditions of nonalcoholic steatohepatitis (NASH) and insulin resistance using a rat model system., Methods: Forty-five male Sprague-Dawley rats were randomly divided into a normal control group (NC, n=10), a model control group (MC, n=15), a polyene phosphatidylcholine prevention group (PP, n=10), and a telmisartan prevention group (TP, n=10). The NC group was given a standard diet and the other groups were given a high-fat diet for 16 weeks in order to induce NASH. At the end of week 12, 5 rats in the MC group were sacrificed for pathology confirmation of the NASH model. At the end of week 12, the TP group was given telmisartan (8.0 mg/kg/d) and the PP group was given polyene phosphatidylcholine (8.4 mg/kg/d) for an additional 4 weeks by intragastric administration. At the end of week 16, all rats were sacrificed and body weights recorded. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglycerides (TG), resistin, insulin and fasting blood glucose were measured. The insulin resistance value, HOMA-IR, was assessed by homeostasis mode assessment. Liver expression of the resistin protein was detected by western blotting and of the resistin mRNA was detected by RT-PCR. The F test and LSD test were used for statistical analyses., Results: Compared to the NC group, the body weight and HOMA-IR of rats in the MC group were significantly increased (P<0.01). The levels of serum resistin, and of resistin protein and mRNA in liver, were significantly higher in the MC group than in the NC group of rats (all P less than 0.01). The body weight of rats in the TP group was significantly lower than those in the MC group (P<0.05). The levels of serrn resistin, resistin protein and mRNA in the liver, and insulin resistance were significantly lower in the TP group than in the MC group of rats (all P<0.01). The PP group did not show significant differences in any of these measures, except for loss of body weight (P<0.05)., Conclusion: Telmisartan elicits preventive and protective effects in a NASH rat model.Telmisartan may improve insulin resistance in NASH rats by decreasing the expression of serum resistin, and liver resistin protein and mRNA.

The dry matter (DM) yield and its characteristics of 28 alfalfa varieties were evaluated in the 4th year under space sowing condition. The results showed that there existed significant difference (P<0.01) in DM yield and its characteristics among the varieties. The highest and higher DM yield were obtained form varieties Xinjiang Deye (452.8 g x plant(-1)) and Gannong No. 3 (373.0 g x plant(-1)), respectively, and the varieties with the highest height and branch/plant at the 3rd cutting were Gannong No. 3, Xinjiang Deye, Weixian, Tumu No. 2, Xinmu No. 1, and Zhaodong. The correlation analysis between DM yield and its characteristics indicated that the main factors affecting yield were the height and the branch/plant. The genetic diversity of DM yield and its components in 28 alfalfa varieties showed that the variations of DM yield and yield components of within-variety were larger than those of among-variety in majority of test varieties. The CV of all characteristics were presented in order of 3rd No. branch/plant>DM yield/plant>1st No. branch/plant>2nd No. branch/plant>Spring height>3rd height>2nd height>leaf width>budding height>leaf length>1st height.

Investigations on the soil seed banks of different grassland types of Alashan arid desert region in Inner Mongolia showed that when the altitudes of sampling plots increased from 1,370 m to 1,750 m, the soil seed densities of natural grasslands decreased from 326 grain.m-2 to 76 grain.m-2. At the altitude of 1,100 m, the soil seed density was 56 grain.m-2 in typical desert plot, but only 8 grain.m-2 in the sand dune plot. After the vegetation was restored with Artemisa sphaerocephala on sand dune, its soil seed density increased obviously, almost as 17-29 times as sand dune's. In this study, 31 seeds m-2 were sampled, which belonged to 11 families. Among them, annual plants accounted for 77%, 100% and 70%, perennial plants accounted for 21%, 0 and 16%, and semi-shrubs accounted for 2%, 0 and 14%, respectively for natural grassland, sand dune and sown grassland. Shrub seeds were not found in all the soil seed bank plots. When the altitudes of sampling plots increased from 1,100 m to 1,750 m, the species richness (Margalet index) of soil seed banks of natural grasslands increased from 1.49 to 2.77, and the species diversity (Shannon-Winner index) increased from 0.697 to 0.917.

Water distribution pattern and water use-efficiency in soil-plant-atmosphere system for light, medium, and heavy degraded Reaumuria soongorica grasslands were studied in Alashan region of Inner Mongolia. The total precipitation in 2001 was 124.3 mm, of which 119.4 mm occured during experimental period. Soil water content (SWC) in 10-40 cm layer was greatly affected by the evapotranspiration. The SWC in 10-20 cm layer of medium degraded grassland paddock was significantly lower (P < 0.05), and the SWC in 20-40 cm layer of light degraded paddock was lower than that of other paddocks due to different transpiration rate and root distribution depth between the main co-existing plant species of R. soongorica and Cleistogenes soongorica in the paddocks. The annual average bare land evaporation and R. soongorica population transpiration were 30.6 mm and 11.9 mm, respectively. As the grassland further degraded, the bare land evaporation and transpiration through Peganum nigellastrum population, a degradation indicating plant species, increased, while the transpiration of R. soongorica decreased. In addition, the water use-efficiency of the grassland and dominant plant species markedly decreased with the increasing grassland degradation. Compared to the light degraded paddocks, for instance, the water use-efficiency of medium and heavy degraded paddocks were reduced by 14.6% and 46.1% for total biomass production, and by 37.8% and 73.8% for R. soongorica, respectively.

The seed germination rate, seed mortality, seedling length, and infection rate of alfalfa (Medicago sativa L. cv. 'Longdong') were measured at constant temperature 20 degrees C every 60 days during one year storage period after inoculated or no inoculated by Fusarium avenaceum under room temperature (RT), 35 degrees C, and 35 degrees C and +10% seed moisture content (SMC) conditions. Field emergence rates of seeds under above treatments were also observed, and seed-borne fungi were detected under the conditions mentioned above and controlled deterioration (CD) as well. The results showed that the percentage of isolated alfalfa seed-borne fungi was increased from 10% under room temperature and 35 degrees C to 29% under 35 degrees C + 10% SMC. Disease resistance was declined, and seed mortality and seedling infection rate under 35 degrees C + 10% SMC were significantly higher than those under room temperature and 35 degrees C respectively (P < 0.05). The seed germination rate and field emergence rate were also decreased significantly (P < 0.05). Seedling shoot and root length under 35 degrees C + 10% SMC were significantly less than those under RT and 35 degrees C respectively (P < 0.05). The percentages of both seed-borne fungi isolated and field emergence were decreased, and that of seedling infection was increased with storage period extending from 60 to 360 days. Compared to no inoculated control, the percentage of seed germination, seedling shoot and root length were decreased, and seed mortality and seedling infection rate were increased after inoculated by F. avenaceum.

The seed germination, seedling growth and water absorption characteristic of Caragana korshinskii, Hedysarum scoparium, and Artemisia sphearocephala were investigated under different osmotic potentials (PEG 6000, -0.3(-) -2.7 MPa). The results showed that under drought stress, C. korshinskii had the highest germination rate, while A. sphearocephala had the lowest one. Under -0.3(-) -0.6 MPa, the root length of 10-day-old A. sphearocephala seedling was significantly longer than that of H. scoparium and Caragana korshinskii(P < 0.05), and the length reached 7.9, 4.5 and 3.1 cm, respectively. There existed a significant positive correlation between seed germination rate and 72 h water absorption rate of the three shrub seeds(P < 0.01). The relationships among germination characteristics, root length, and survive percentage of seedlings were also discussed.

Drought stress is a bottleneck factor for plant growth and development. Synthesis and accumulation of osmoprotectants, up-regulation of gene expression implicated in repair of desiccation injury, free radical-scavenging enzymes and late-embryogenesis-abundant(LEA) protein could increase the drought tolerance of plant. There are at least for pathways of signal transduction in plant subjected to drought stress, two are abscisic acid(ABA)-dependent, and two are ABA-independent. In the signal transduction of plants encountered drought stress, two-component His protein kinase could act as an osmosensor, and Ca2+ and inositol triphosphate(IP3) could be the second messenger for dehydration signaling. Transgenic plant is an excellent system in evaluating function of encoded protein.

Seed yield and its characteristics of 28 varieties of Poa pratensis in field plots at Lanzhou, China were evaluated in 2001. The results showed that the seed yields among the varieties were significantly different (P < 0.01) by LSD test. The highest yield was 643.4-650.2 kg.hm-2 obtained from varieties of Balin and Monoply, the lowest was 90.1 kg.hm-2 obtained from Elysee, and the other varieties were in the middle groups with the yields varied from 114.7 kg.hm-2 to 435.1 kg.hm-2. Correlation analysis between seed yield and yielding characteristics indicated that the main factors affecting seed yield were the number of fertile tillers per plant (r = 0.785), the height of fertile tiller (r = 0.712), the length of inflorescence (r = 0.743), and the number of spikelets/fertile tiller (r = 0.786). Cluster analysis for seed production capacity based on seed yield and above-mentioned 4 main characteristics showed that the 28 varieties could be divided into 6 grades.