Water absorption and maintenance of nanofiber cellulose production by Gluconacetobacter rhaeticus TL-2C

Physiochemical properties of bacterial cellulose producing by Gluconacetobacter rhaeticus TL-2C was investigated for confirming its possibility as wound care dressing material. Scanning electron micrograph showed that the diameter of bacterial cellulose fiber was 40 to 50 nm. Solid state 13C nuclear magnetic resonance (NMR) data showed that the bacterial cellulose had amorphous peak of C-4 and C-6 and the crystallinity index of bacterial cellulose was 75.4. Water absorption ability of bacterial cellulose was 19-fold higher than α-cellulose. Bacterial cellulose had 2-fold higher water maintenance ability than α-cellulose.Key words: Bacterial cellulose, Gluconacetobacter rhaeticus, nanofiber, water absorption

Impact of Vegetation on Land-Atmosphere Coupling Strength and Its Implication for Desertification Mitigation over East Asia

Desertification of the East Asian drylands and the consequent dust transport have been serious concerns for adjacent Asian countries as well as the western United States. Tree planting has been considered one applicable strategy to mitigate the desertification. However, the desired effect of the tree planting would not be brought to fruition unless the newly planted trees change the coupling characteristics between the land and the atmosphere. Based on this perception, we attempt to clarify the effects of vegetation on the coupling strength between the atmosphere and land surface, and we suggest the most efficient areas of tree planting for desertification mitigation in East Asia. Using regional vegetation-atmosphere coupled model simulations, coupling strength with and without vegetation was computed and compared with each other. An increased vegetation fraction reduces the coupling strength in June, July, and August (JJA), primarily due to decreased evapotranspiration variability. This effect is pronounced over the Manchurian Plains and the highly populated areas of Beijing and Tianjin. The reduced coupling strength tends to weaken feedback between soil moisture and precipitation as a maintenance mechanism of warm season droughts in the midlatitudes and subsequently decrease the probability of droughts, a finding that is reflected in the enhanced JJA mean soil moisture. However, some drylands like the eastern edges of the Gobi desert present marginal or even opposite changes in coupling strength, meaning a limited effect of vegetation on relieving droughts. Therefore, given limited financial and human resources, acupuncture-like afforestation, i.e., concentrated tree planting in a particular region where the coupling strength can be substantially reduced by vegetation, is an effective strategy to secure long-standing desertification mitigation

Effect of cytokinins on growth and phenylpropanoid accumulation in Tartary buckwheat sprouts (Fagopyrum esculentum Moench)

This study analyzed the effect of plant hormones, zeatin, 6-benzyl amino purine (BAP), kinetin, and thidiazuron (TDZ) on the growth of Tartary buckwheat sprouts and analyzed the fresh weight, shoot and root length, and production of phenolic compounds. All the hormone-treated plants at the lowest concentration (0.1 mg/L) showed the highest levels of growth parameters (fresh weight, shoot, and root length) when compared to the control. Among the various hormones treatment, the plant treated with 1 mg/L of BAP, kinetin, and zeatin showed the highest total phenolic level, whereas the TDZ showed the highest accumulation of total phenolic at the lowest concentration (0.1 mg/L). A total of 6 compounds were identified (4-hydroxybenzoic acid, caffeic acid, chlorogenic acid, p-coumaric acid, rutin, and trans-cinnamic acid) were quantified by high liquid performance chromatography (HPLC) after treatment of plant with different concentrations of hormones. Among these individual phenolic compounds, at the higher hormonal concentration (1 mg/L) the rutin showed the highest accumulation in BAP, zeatin, and kinetin treated sprout, whereas in the TDZ treated sprout the rutin content was highest at the lowest concentration (0.1 mg/L). From these results, it is suggested that BAP, zeatin, and kinetin at the lowest concentrations might positively enhance the growth of buckwheat sprouts, whereas at the highest hormonal treatment the accumulation of the phenolic compounds was higher. However, in TDZ treatment the growth and phenolic compound accumulation were highest at the lowest concentration. From these results, it is showed that suitable concentrations might enhance the growth and phenolic compound accumulation in Tatary buckwheat sprout

Discrimination of cultivation ages and cultivars of ginseng leaves using Fourier transform infrared spectroscopy combined with multivariate analysis

AbstractTo determine whether Fourier transform (FT)-IR spectral analysis combined with multivariate analysis of whole-cell extracts from ginseng leaves can be applied as a high-throughput discrimination system of cultivation ages and cultivars, a total of total 480 leaf samples belonging to 12 categories corresponding to four different cultivars (Yunpung, Kumpung, Chunpung, and an open-pollinated variety) and three different cultivation ages (1 yr, 2 yr, and 3 yr) were subjected to FT-IR. The spectral data were analyzed by principal component analysis and partial least squares-discriminant analysis. A dendrogram based on hierarchical clustering analysis of the FT-IR spectral data on ginseng leaves showed that leaf samples were initially segregated into three groups in a cultivation age-dependent manner. Then, within the same cultivation age group, leaf samples were clustered into four subgroups in a cultivar-dependent manner. The overall prediction accuracy for discrimination of cultivars and cultivation ages was 94.8% in a cross-validation test. These results clearly show that the FT-IR spectra combined with multivariate analysis from ginseng leaves can be applied as an alternative tool for discriminating of ginseng cultivars and cultivation ages. Therefore, we suggest that this result could be used as a rapid and reliable F1 hybrid seed-screening tool for accelerating the conventional breeding of ginseng

Mild Hypothermia Attenuates Intercellular Adhesion Molecule-1 Induction via Activation of Extracellular Signal-Regulated Kinase-1/2 in a Focal Cerebral Ischemia Model

Intercellular adhesion molecule-1 (ICAM-1) in cerebral vascular endothelium induced by ischemic insult triggers leukocyte infiltration and inflammatory reaction. We investigated the mechanism of hypothermic suppression of ICAM-1 in a model of focal cerebral ischemia. Rats underwent 2 hours of middle cerebral artery occlusion and were kept at 37°C or 33°C during occlusion and rewarmed to normal temperature immediately after reperfusion. Under hypothermic condition, robust activation of extracellular signal-regulated kinase-1/2 (ERK1/2) was observed in vascular endothelium of ischemic brain. Hypothermic suppression of ICAM-1 was reversed by ERK1/2 inhibition. Phosphorylation of signal transducer and activator of transcription 3 (STAT3) in ischemic vessel was attenuated by hypothermia. STAT3 inhibitor suppressed ICAM-1 production induced by stroke. ERK1/2 inhibition enhanced phosphorylation and DNA binding activity of STAT3 in hypothermic condition. In this study, we demonstrated that hypothermic suppression of ICAM-1 induction is mediated by enhanced ERK1/2 activation and subsequent attenuation of STAT3 action

Deformations of coisotropic submanifolds and strong homotopy Lie algebroids

In this paper, we study deformations of coisotropic submanifolds in a symplectic manifold. First we derive the equation that governs $C^\infty$ deformations of coisotropic submanifolds and define the corresponding $C^\infty$-moduli space of coisotropic submanifolds modulo the Hamiltonian isotopies. This is a non-commutative and non-linear generalization of the well-known description of the local deformation space of Lagrangian submanifolds as the set of graphs of {\it closed} one forms in the Darboux-Weinstein chart of a given Lagrangian submanifold. We then introduce the notion of {\it strong homotopy Lie algebroid} (or {\it $L_\infty$-algebroid}) and associate a canonical isomorphism class of strong homotopy Lie algebroids to each pre-symplectic manifold $(Y,\omega)$ and identify the formal deformation space of coisotropic embeddings into a symplectic manifold in terms of this strong homotopy Lie algebroid. The formal moduli space then is provided by the gauge equivalence classes of solutions of a version of the {\it Maurer-Cartan equation} (or the {\it master equation}) of the strong homotopy Lie algebroid, and plays the role of the classical part of the moduli space of quantum deformation space of coisotropic $A$-branes. We provide a criterion for the unobstructedness of the deformation problem and analyze a family of examples that illustrates that this deformation problem is obstructed in general and heavily depends on the geometry and dynamics of the null foliation.Comment: 60 pages, This is the final version that will appear in Invent. Mat

Commission des Communautes Europeennes: Groupe du Porte-Parole. Reunion de la Commission du 27/6/79 = Commission of European Communities: Spokesman Group. Meeting of the Commission on 27/6/79. Spokesman Service Note to National Offices Bio No. (79) 210, 27 June 1979

Rabi oscillations of a two-level atom appear as a quantum interference effect between the amplitudes associated to atomic superpositions, in analogy with the classic double-slit experiment which manifests a sinusoidal interference pattern. By extension, through direct detection of time-resolved resonance fluorescence from a quantum-dot neutral exciton driven in the Rabi regime, we experimentally demonstrate triple-slit-type quantum interference via quantum erasure in a V-type three-level artificial atom. This result is of fundamental interest in the experimental studies of the properties of V-type 3-level systems and may pave the way for further insight into their coherence properties as well as applications for quantum information schemes. It also suggests quantum dots as candidates for multi-path-interference experiments for probing foundational concepts in quantum physics.Comment: 5 pages, 4 figures. Accepted versio