Homogeneous synthesis of cellulose acrylate-g-poly (n-alkyl acrylate) solid-solid phase change materials via free radical polymerization.

A novel solid-solid phase change materials, namely, cellulose acrylate-g-poly (n-alkyl acrylate) (CA-g-PAn) (n = 14, 16 and 18) were successfully synthesized by free radical polymerization in N, N-dimethylacetamide (DMAc). The successful grafting was confirmed by fourier transform infrared spectra (FT-IR) and nuclear magnetic resonance (NMR). The properties of the CA-g-PAn copolymers were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA). The phase change temperatures and the melting enthalpies of CA-g-PAn copolymers are in the range of 10.1-53.2 °C and 15-95 J/g, respectively. It can be adjusted by the contents of poly (n-alkyl acrylate) and the length of alkyl side-chain. The thermal resistant temperatures of CA-g-PA14, 16 and 18 copolymers are 308 °C, 292 °C and 273 °C, respectively. It show that all of grafting materials exhibit good thermal stability and shape stability. Therefore, it is expected to be applied in the cellulose-based thermos-regulating field.

Comparison of diagnostic values of different imaging techniques for hip joint lesion of patient with ankylosing spondylitis / 医疗卫生装备

Objective To study the diagnostic values of X-ray,CT and MRI for the hip joint lesion of the patient with ankylosing spondylitis (AS).Methods Totally 180 AS patients underwent the examinations of X-ray,CT and MRI from January 2014 to December 2015,and the hip joint lesion,clinical features and the efficacies of the three imaging techniques were observed.Results The rates for positive findings were 69.44％,71.11％ and 72.22％ respectively by X-ray,CT and MRI,and more than 90％ patients had the lesions occurred at the bilateral hip joints simultaneously.Hip joint lesion of AS had the imaging features of bone marrow and joint space changes,which related to the disease progress closely.Early positive signs consisted of medial joint space narrowing by X-ray,rear joint space narrowing by CT as well as bone marrow fat deposition (BMFD) and bone marrow edema (BME) by MRI.Conclusion X ray,CT and MRI all gain their advantages when used to diagnose the hip joint lesion of AS.X-ray behaves well in early diagnosis of medial joint space narrowing,while have disadvantages in displaying soft tissues and minute structures when compared with CT and MRI.CT displays the minute structure of hip joint clearly,and is not so good at soft tissue resolution as MRI.MRI gains the highest resolution for displaying soft tissues in the three techniques,and can show BMFD,BME and etc which can not be revealed by X-ray and CT.

Comparison of diagnostic values of different imaging techniques for hip joint lesion of patient with ankylosing spondylitis / 医疗卫生装备

Objective To study the diagnostic values of X-ray,CT and MRI for the hip joint lesion of the patient with ankylosing spondylitis (AS).Methods Totally 180 AS patients underwent the examinations of X-ray,CT and MRI from January 2014 to December 2015,and the hip joint lesion,clinical features and the efficacies of the three imaging techniques were observed.Results The rates for positive findings were 69.44％,71.11％ and 72.22％ respectively by X-ray,CT and MRI,and more than 90％ patients had the lesions occurred at the bilateral hip joints simultaneously.Hip joint lesion of AS had the imaging features of bone marrow and joint space changes,which related to the disease progress closely.Early positive signs consisted of medial joint space narrowing by X-ray,rear joint space narrowing by CT as well as bone marrow fat deposition (BMFD) and bone marrow edema (BME) by MRI.Conclusion X ray,CT and MRI all gain their advantages when used to diagnose the hip joint lesion of AS.X-ray behaves well in early diagnosis of medial joint space narrowing,while have disadvantages in displaying soft tissues and minute structures when compared with CT and MRI.CT displays the minute structure of hip joint clearly,and is not so good at soft tissue resolution as MRI.MRI gains the highest resolution for displaying soft tissues in the three techniques,and can show BMFD,BME and etc which can not be revealed by X-ray and CT.

Identification of suitable reference genes in buffalo grass for accurate transcript normalization under various abiotic stress conditions.

Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) is a sensitive technique for normalization of the gene expression level of target genes. Buffalograss (Buchloe dactyloides), a warm-season turfgrass with strong abiotic stress resistance, is widely used in North China. Up to now, no work was performed to evaluate the reference genes in buffalograss. In this study, the expression profiles of ten potential reference genes were examined by qRT-PCR in 24 buffalograss samples, which were subjected to a different treatment (salt, osmotic, cold and heat). Three qRT-PCR analysis methods (GeNorm, NormFinder, and Bestkeeper) were used to evaluate the stability of gene expression. The results indicated that DNAJ and ß-ACTIN were the optimal reference genes for salt-treated leaves, and the combination of PP2A and GAPDH was better reference genes for PEG-treated leaves. Under cold stress, DNAJ and ß-ACTIN showed less variety of expression level in leaves. DNAJ and GAPDH exhibited the most stable expression in heat-treated samples. To sum up, glyceral-dehyde-3-phosphate dehydrogenase (GAPDH), ß-ACTIN, DNAJ-like protein (DNAJ) and protein phosphatase 2A (PP2A) were selected as the most stable reference gene among all tested samples. To further validate the suitability of these reference genes, the expression levels of DREB2 (homologs of AtDREB2) were analyzed in parallel. Our results show that the best reference genes differed across different experimental conditions, and these results should enable better normalization and quantification of transcript levels in buffalograss in the future.

Phenotypic Responses of a Stoloniferous Clonal Plant Buchloe dactyloides to Scale-Dependent Nutrient Heterogeneity.

Clonal plants could modify phenotypic responses to nutrients heterogeneously distributed both in space and time by physiological integration. It will take times to do phenotypic responses to modifications which are various in different growth periods. An optimal phenotype is reached when there is a match between nutrient conditions and foraging ability. A single plantlet of Buchloe dactyloides with two stolons was transplanted into heterogeneous nutrient conditions. One stolon grew in homogeneous nutrient patch, while the other cultured in different scales of heterogeneous nutrient patches. As compared to the other nutrient treatment, heterogeneous nutrient treatments with small scale of 25×25 cm resulted in a higher biomass, and larger number of ramets, clumps and stolons in B. dactyloides at both genet and clonal fragment levels. Significant differences of number of ramets, clumps and stolons were detected at the rapid growth stage, but not in the early stage of the experiment. Foraging ability was more efficient in heterogeneous than in homogeneous nutrient conditions as assessed by higher root mass and root to shoot ratio. Different nutrient treatments did not prompt significant differences in internode and root length. Physiological integration significantly increased biomass, but did not influence other growth or morphological characters. These results suggest that physiological integration modifies phenotypic plasticity of B. dactyloides for efficient foraging of nutrients in heterogeneous nutrient conditions. These effects are more pronounced at genet and clonal fragment levels when the patch scale is 25×25 cm. Time is a key factor when phenotypic plasticity of B. dactyloides in heterogeneous nutrient conditions is examined.