Synthesis and rheological characterization of water-soluble glycidyltrimethylammonium-chitosan.

In this study, chitosan (CS) grafted by glycidyltrimethylammonium chloride (GTMAC) to form GTMAC-CS was synthesized, chemically identified, and rheologically characterized. The Maxwell Model can be applied to closely simulate the dynamic rheological performance of the chitosan and the GTMAC-CS solutions, revealing a single relaxation time pertains to both systems. The crossover point of G' and G" shifted toward lower frequencies as the CS concentration increased but remained almost constant frequencies as the GTMAC-CS concentration increased, indicating the solubility of GTMAC-CS in water is good enough to diminish influence from the interaction among polymer chains so as to ensure the relaxation time is independent of the concentration. A frequency-concentration superposition master curve of the CS and GTMAC-CS solutions was subsequently proposed and well fitted with the experimental results. Finally, the sol-gel transition of CS is 8.5 weight % (wt %), while that of GTMAC-CS is 20 wt %, reconfirming the excellent water solubility of the latter.

Shell Theory: A Statistical Model of Reality.

The foundational assumption of machine learning is that the data under consideration is separable into classes; while intuitively reasonable, separability constraints have proven remarkably difficult to formulate mathematically. We believe this problem is rooted in the mismatch between existing statistical techniques and commonly encountered data; object representations are typically high dimensional but statistical techniques tend to treat high dimensions a degenerate case. To address this problem, we develop a dedicated statistical framework for machine learning in high dimensions. The framework derives from the observation that object relations form a natural hierarchy; this leads us to model objects as instances of a high dimensional, hierarchal generative processes. Using a distance based statistical technique, also developed in this paper, we show that in such generative processes, instances of each process in the hierarchy, are almost-always encapsulated by a distinctive-shell that excludes almost-all other instances. The result is shell theory, a statistical machine learning framework in which separability constraints (distinctive-shells) are formally derived from the assumed generative process.

Probiotic applications of two dominant gut Bacillus strains with antagonistic activity improved the growth performance and immune responses of grouper Epinephelus coioides.

The effect of dietary administration of Bacillus pumilus and Bacillus clausii, the dominant bacteria with antagonistic activity in the gut of fast growing fish, on the growth performance and immune responses of grouper Epinephelus coioides were assessed. The fish were fed for 60 days with three different diets: control (without probiotics), diet T1 supplemented with 1.0x10(8) cells g(-1) B. pumilus, diet T2 with 1.0x10(8) cells g(-1) B. clausii. No significant improvements of weight gain or specific growth rate were observed in the probiotic fed groups, but a significant improvement of feed conversion ratio was observed after 60 days of feeding. Phagocytic activity and phagocytic index of fish fed probiotic diets were significantly higher than those of fish fed the control diet for 60 days. Superoxide dismutase (SOD) concentrations showed no significant difference between the treatments and the control during the whole experiment period, but which increased by 11.4% and 18.5% after 60 days of fed with diets T1 and T2, respectively. The serum lysozyme activities of fish fed diets T1 and T2 were significantly higher than that of fish fed control diet, and had respectively increased by 34.7% and 17.4% compared to the control after 60 days of feeding. Serum complement C3 levels of the treatments were significantly higher than that of control after 30 days of feeding, but no significant difference in serum complement C3 and C4 levels were observed between the treatments and the control after 60 days of feeding. The serum IgM levels of fish fed diet T1 and diet T2 were higher than that of fish fed control diet, and significant increase was observed in fish fed diet T2 for 30 days. The results demonstrated potential for B. pumilus and B. clausii to improve growth performance and immune responses of E. coioides.

[Studies on chemical constituents from herbs of Taraxacum mongolicum].

OBJECTIVE: To investigate the chemical constituents of the herbs of Taraxacum mongolicum. METHOD: The chemical constituents were isolated by various column chromatographic methods and their structures elucidated mainly by NMR and MS evidences. RESULT: Forty-four components were obtained and identified were as artemetin (1), quercetin (2), quercetin-3', 4', 7-trime-thyl ether (3), luteolin (4), luteolin-7-O-beta-D-glucopyranoside (5), luteolin-7-O-beta-D-galactopyranoside (6), genkwanin (7), isoetin (8), hesperetin (9), genkwanin-4'-O-beta-D-lutinoside (10), hesperidin (11), quercetin-7-O-[beta-D-glucopyranosyl (1-->6) -beta-D-glucopyranoside (12), quercetin-3, 7-O-beta-D-diglucopyranoside (13), isoetin-7-O-beta-D-glucopyranosyl- 2'-O-alpha-L-arabinopyranoside (14), isoetin-7-O-beta-D-glucopyranosyl-2'-O-alpha-D-glucopyranoside (15), isoetin-7- O-beta-D-glucopyranosyl-2'-O-beta-D-xyloypyranoside (16), caffeic acid (17), furulic acid (18), 3-O-caffeoylquinic acid (19), 3, 5-di-O-caffeoylquinic acid (20), 3, 4-di-O-caffeoylquinic acid (21), 4, 5-di-O-caffeoylquinic acid (22), 1-hydroxymethyl-5-hydroxy-phenyl-2-O-beta-D-glucopyranoside (23), p-hydroxybenzoic acid (24), p-coumaric acid (25), 3, 5-dihydroxylbenzoic acid (26), gallic acid (27), gallicin (28), syringic acid (29), 3, 4-dihydroxybenzoic acid (30), caffeic acid ethyl ester (31), esculetin (32), rufescidride (33), mongolicumin A [6, 9, 10-trihydroxy-benzoxanthene-1, 2-dicarboxylic acid] (34), mongolicumin B [1 l-hydroxy-2-oxo-guaia-1 (10), 3, 5-trien-8, 12-lactone] (35), isodonsesquitin A (36), taraxacin (37), sesquiterpene ketolactone (38), taraxasteryl acetate (39), phi-taraxasteryl acetate (40) and lupenol acetate (41), palmitic acid (42), beta-sitosterol (43), and stigmasterol (44). CONCLUSION: Four compounds (14, 15, 34 and 35) were new compounds, compounds 1, 3, 6-13, 20-22, 30 and 31 were isolated from this genus for the first time, while compounds 18, 23-29, 32 and 37-42 were obtained from this species for the first time.

CODE: Coherence Based Decision Boundaries for Feature Correspondence.

A key challenge in feature correspondence is the difficulty in differentiating true and false matches at a local descriptor level. This forces adoption of strict similarity thresholds that discard many true matches. However, if analyzed at a global level, false matches are usually randomly scattered while true matches tend to be coherent (clustered around a few dominant motions), thus creating a coherence based separability constraint. This paper proposes a non-linear regression technique that can discover such a coherence based separability constraint from highly noisy matches and embed it into a correspondence likelihood model. Once computed, the model can filter the entire set of nearest neighbor matches (which typically contains over 90 percent false matches) for true matches. We integrate our technique into a full feature correspondence system which reliably generates large numbers of good quality correspondences over wide baselines where previous techniques provide few or no matches.

[Studies on constitutes from Taraxacum mongolicum].

OBJECTIVE: To study the chemical constituents of Taraxacum mongolicum. METHOD: Repeated column chromatography over silica gel, C-18 and Sephadex LH-20 were used to isolate chemical constitutes and their structures were elucidated by spectroscopic methods MS, 1H-NMR, 13C-NMR including 2D-NMR techniques and by direct comparing spectral data with those reported in literatures. RESULT: Eight compounds were identified as artemetin (1), quercetin (2), luteolin (3), luteolin-7-O-beta-D-glucopyranoside (4), caffeic acid (5), esculetin (6), stigmasterol (7), taraxasteryl acetate (8), respectively. CONCLUSION: Compound 1 was obtained from this genus and compound 6, 8 from this species for the first time. Furthermore, the 13 carbon data of compound 6 from the literature were corrected with 2D-NMR techniques in this paper.

Patients with knee osteoarthritis undergoing total knee arthroplasty have a lower risk of subsequent severe cardiovascular events: propensity score and instrumental variable analysis.

OBJECTIVE: This population-based study investigated the subsequent cardiovascular risk of patients with knee osteoarthritis underwent total knee arthroplasty in Taiwan. MATERIALS AND METHODS: This was a population-based follow-up study of 22931 patients diagnosed with knee osteoarthritis between 2008 and 2011. Each patient was followed for 3 years or until death. Treatment was dichotomized into conservative treatment and TKA. The association between TKA and cardiovascular disease (CVD) events was analyzed using propensity score analysis and instrumental variable analysis and two-stage least-squares regression model. RESULTS: Patients with knee osteoarthritis who underwent TKA had a lower 3-year cumulative risk of stroke and acute myocardial infarction (AMI). After adjusting for measured risk and confounding factors, propensity score showed a 0.56 fold (adjusted OR = 0.56; 95% CI, 0.51-0.61; p<0.001) risk for CVD in those with TKA. Use of instrumental variable analysis for adjusting measured and unmeasured factors and two-stage least squares regression model revealed that the average treatment effect of TKA was statistically associated with a decreased 7% risk of CVD events (95% CI, 0.2%-13.6%). CONCLUSION: Our study revealed that patients with knee osteoarthritis who underwent TKA had a lower risk of suffering from a future severe cardiovascular event. This benefit may be attributed to an improvement in physical activity, reduction of psychosocial stress, and/or a decreased use of NSAIDs as a result of having undergone TKA.

Taraxacum mongolicum extract exhibits a protective effect on hepatocytes and an antiviral effect against hepatitis B virus in animal and human cells.

In order to validate the antiviral effect against hepatitis B virus (HBV) of Taraxacum mongolicum (T. mongolicum), the protective effect on hepatocytes, and antiviral properties against duck hepatitis B virus (DHBV) and HBV of T. mongolicum extract (TME) were evaluated in chemically-injured neonatal rat hepatocytes, DHBV-infected duck fetal hepatocytes and HBV-transfected HepG2.2.15 cells, respectively. The results demonstrated that TME at 50-100 µg/ml improved D-galactosamine (D-GalN), thioacetamide (TAA) and tert-butyl hydroperoxide (t-BHP)-injured rat hepatocytes, and produced protection rates of 42.2, 34.6 and 43.8% at 100 µg/ml, respectively. Furthermore, TME at 1-100 µg/ml markedly inhibited DHBV DNA replication. Additionally, TME at 25-100 µg/ml reduced HBsAg and HBeAg levels and produced inhibition rates of 91.39 and 91.72% at 100 µg/ml, respectively. TME markedly inhibited HBV DNA replication at 25-100 µg/ml. The results demonstrate the potent antiviral effect of T. mongolicum against HBV effect. The protective of TME effect on hepatocytes may be achieved by its ability to ameliorate oxidative stress. The antiviral properties of TME may contribute to blocking protein synthesis steps and DNA replication. Furthermore, major components of TME were quantificationally analyzed. These data provide scientific evidence supporting the traditional use of TME in the treatment of hepatitis.