Obesity not only adds to the mass that must be carried during walking, but also changes body composition. Although extra mass causes roughly proportional increases in musculoskeletal loading, less well understood is the effect of relatively soft and mechanically compliant adipose tissue. Purpose To estimate the work performed by soft tissue deformations during walking. The soft tissue would be expected to experience damped oscillations, particularly from high force transients following heel strike, and could potentially change the mechanical work demands for walking. Method We analyzed treadmill walking data at 1.25 m/s for 11 obese (BMI > 30 kg/m2) and 9 non-obese (BMI < 30 kg/m2) adults. The soft tissue work was quantified with a method that compares the work performed by lower extremity joints as derived using assumptions of rigid body segments, with that estimated without rigid body assumptions. Results Relative to body mass, obese and non-obese individuals perform similar amounts of mechanical work. But negative work performed by soft tissues was significantly greater in obese individuals (p= 0.0102), equivalent to about 0.36 J/kg vs. 0.27 J/kg in non-obese individuals. The negative (dissipative) work by soft tissues occurred mainly after heel strike, and for obese individuals was comparable in magnitude to the total negative work from all of the joints combined (0.34 J/kg vs. 0.33 J/kg for obese and non-obese adults, respectively). Although the joints performed a relatively similar amount of work overall, obese individuals performed less negative work actively at the knee. Conclusion The greater proportion of soft tissues in obese individuals results in substantial changes in the amount, location, and timing of work, and may also impact metabolic energy expenditure during walking.

The gut microbiota, including pathogenic microorganisms and probiotics, has been involved in tumor initiation and progression by regulating the components of intestinal flora. Canmei formula (CMF), a traditional Chinese medicine, chronicled in the Chuang Yang Jing Yan Quan Shu, has been clinically used as an adjuvant therapy to treat patients with colorectal carcinoma (CRC) in China. In this study, we investigate the treatment effect of CMF in the azoxymethane (AOM) and dextran sodium sulfate (DSS) induced and high-fat diet augmented colitis-associated colorectal cancer in vivo, and explore its mechanism of action. We found that CMF treatment relieved the inflammation and alteration of the gut microbiota and significantly inhibited the development of intestinal adenoma. Linear discriminant analysis showed that the flora diversity in the normal mice, model mice and CMF treatment mice was different. At the family level, the relative abundance of Desulfovibrionaceae decreased in CMF groups. The relative abundance of Desulfovibrionaceae were lower in the CMF groups than in model group, whereas Rikenellaceae and Alistipes were increased. Altogether our results indicate that CMF treatment ameliorate colitis-associated colorectal carcinogenesis by modulating the composition of the gut microbiota in vivo.

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Taking the marsh meadowDeyeuxia angustifoliain San Jiang Plain of Northeast China as test material,a field experiment was carried out with treatments different in nitrogen supply (0,4,8g/m2) to investigate the effects the soil nutrient content.The results showed that difference among layers soil organic matter activity firstly increased and then decreased with increasing of nitrogen addition. Difference among layers soil total nitrogen contains were no significant differences. Soil total nitrogen contains reduced gradually in the 0-10cm layers,in the 10-20cm and 20-30cm layers firstly increased and then decreased. Difference among layers soil ammonium N contains were no significant differences.The 0-10cm and 20-30cm layers soil total NO-3-N firstly increased and then decreased,10-20cm layers firstly decreased and then increased. Difference among layers soil nitrate N contains obviously different levels (p<0.05). With increasing of nitrogen addition, the 0-10cm and 10-20cm layers soil total phosphoru contains increased gradually,20-30cm layers firstly increased and then decreased. With increasing of nitrogen addition,difference among layers soil total potassium contains were no significant differences.

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Response of soil respiration in temperate wetlands in northeast China was studied from June 2009 to September 2011. Li-Cor 6400 infrared gas analyzer connected with a chamber was used to quantify the soil respiration. Results showed that soil respiration displayed a distinct seasonal pattern, with higher values observed in midsummer and lower values in spring and autumn. Furthermore, soil respiration exhibited a significant inter-annual variation. In addition, soil respiration presented significant positive exponential relationships with soil temperature. Whereas, significant exponential decay relationships between soil respiration rate and soil water content was found. In this ecosystem, soil temperature, soil water content and plant phenology together control soil respiration.

It has widely been demonstrated that nitrogen (N) addition enhances plant growth and net primary productivity of terrestrial ecosystems. Moreover, N enrichment could have a profound impact on ecosystem carbon fluxes, especially in the regions where N is deficient. However, there is still debate on how N affects net ecosystem CO2 exchange (NEE). A field experiment manipulating N has been conducted in Calamagrostis anagustifolia community of Sanjiang Plain marsh of northeastern China from 2009 to 2010. N was added at a rate of 5 and 10gN m -2 yr -1with NH4NO3. The results for the 2 yr showed that gross ecosystem productivity (GEP) was higher than ecosystem respiration, leading to net carbon(C)sink (measured by NEE) over the growing season in the study site. Furthermore, low nitrogen (LN) and high nitrogen (HN) addition all significantly stimulated growing-season NEE, on average, by 22 and 36%, respectively. It’s indicated that air temperature plays a major role in regulating ecosystem net C exchange and their responses to climatic change in Sanjiang Plain of northern China. we need long-term field studies to predict the long-term effects of N deposition on ecosystem processes.