Biotemplated Morpho Butterfly Wings for Tunable Structurally Colored Photocatalysts.

Morpho sulkowskyi butterfly wings contain naturally occurring hierarchical nanostructures that produce structural coloration. The high aspect ratio and surface area of these wings make them attractive nanostructured templates for applications in solar energy and photocatalysis. However, biomimetic approaches to replicate their complex structural features and integrate functional materials into their three-dimensional framework are highly limited in precision and scalability. Herein, a biotemplating approach is presented that precisely replicates Morpho nanostructures by depositing nanocrystalline ZnO coatings onto wings via low-temperature atomic layer deposition (ALD). This study demonstrates the ability to precisely tune the natural structural coloration while also integrating multifunctionality by imparting photocatalytic activity onto fully intact Morpho wings. Optical spectroscopy and finite-difference time-domain numerical modeling demonstrate that ALD ZnO coatings can rationally tune the structural coloration across the visible spectrum. These structurally colored photocatalysts exhibit an optimal coating thickness to maximize photocatalytic activity, which is attributed to trade-offs between light absorption and catalytic quantum yield with increasing coating thickness. These multifunctional photocatalysts present a new approach to integrating solar energy harvesting into visually attractive surfaces that can be integrated into building facades or other macroscopic structures to impart aesthetic appeal.

Comparative evaluation of apical microleakage in immediate and delayed postspace preparation using four different root canal sealers: An in vitro study.

BACKGROUND: Endodontically treated teeth often lack sufficient support for a permanent restoration. During post space preparation, it is important not to disturb the integrity of the apical seal. AIM: This study compared the effect of immediate versus delayed post space preparation on the apical seal using four different sealers. MATERIALS AND METHODS: One hundred and thirty single rooted teeth were biomechanically prepared and obturated with single cone gutta-percha and 4 sealers: Endoflas FS, AH Plus, Gutta flow and MTA. Teeth were divided randomly into eight groups, post spaces were prepared using Gates Glidden drills immediately for group I, III, IV and VII. For groups II, IV, VI and VIII prepared after storage of the specimens in 100% humidity for one week. The samples were kept in methylene blue dye, centrifuged at 3000 rpm for 3 min sectioned and then measured under stereomicroscope for apical leakage. STATISTICAL ANALYSIS: The data was analysed using one way ANOVA and post hoc Tukey test. RESULTS: All the specimens showed dye leakage, and a statistically significant difference was seen among all the groups (P > 0.05) except Gutta flow. CONCLUSION: Less leakage is seen when post space is prepared immediately.

Effect of Jyotishmati (Celastrus paniculatus) seeds in animal models of pain and inflammation.

BACKGROUND: Jyotishmati, scientifically known as Celastrus paniculatus Wild (Celastraceae) is one of the most important medicinal plants in Ayurveda. The plant has shown significant pharmacological activities like anti-arthritic, wound healing, hypolipidemic, and antioxidant. OBJECTIVE: To study possible effects of alcoholic extract of Celastrus paniculatus seeds (AlcE) in experimentally induced pain and inflammation in mice. MATERIALS AND METHODS: The antinociceptive activity was evaluated in Swiss albino mice by tail immersion, hot plate, and acetic-acid-induced writhing tests at doses of 250, 500, and 1,000 mg/kg. Anti-inflammatory activity was evaluated in model of carrageenan-induced acute plantar inflammation in Wistar rats. RESULTS: In tail immersion test, AlcE showed significant (P < 0.05) increase in tail withdrawal response at dose of 250 mg/kg with maximum possible effect of 15.71%. The maximum possible effect of 23.32% and 30.16% (P < 0.001) was seen at dose of 500 and 1000 mg/kg at 3 hours after administration of extract, respectively. In hot plate test, increase in paw licking time was reported at dose of 500 and 1000 mg/kg. AlcE (1,000 mg/kg) showed maximum response (6.23 ± 0.46) when compared with control (3.20 ± 0.18) at 90 min. In acetic acid induced writhings, AlcE at dose of 250, 500, and 1,000 mg/kg body weight showed 32.35%, 49.01%, and 58.82% inhibition in writhings, respectively. AlcE treated animals (500 and 1,000 mg/kg) showed significant decrease in paw edema at 3 hours and 4 hours, when compared with control animals. CONCLUSION: Jyotishmati seed extract possesses significant antinociceptive and anti-inflammatory activity.

Formation of embryoid bodies using dielectrophoresis.

Embryoid body (EB) formation forms an important step in embryonic stem cell differentiation invivo. In murine embryonic stem cell (mESC) cultures EB formation is inhibited by the inclusion of leukaemic inhibitory factor (LIF) in the medium. Assembly of mESCs into aggregates by positive dielectrophoresis (DEP) in high field regions between interdigitated oppositely castellated electrodes was found to initiate EB formation. Embryoid body formation in aggregates formed with DEP occurred at a more rapid rate-in fact faster compared to conventional methods-in medium without LIF. However, EB formation also occurred in medium in which LIF was present when the cells were aggregated with DEP. The optimum characteristic size for the electrodes for EB formation with DEP was found to be 75-100 microns; aggregates smaller than this tended to merge, whilst aggregates larger than this tended to split to form multiple EBs. Experiments with ESCs in which green fluorescent protein (GFP) production was targeted to the mesodermal gene brachyury indicated that differentiation within embryoid bodies of this size may preferentially occur along the mesoderm lineage. As hematopoietic lineages during normal development derive from mesoderm, the finding points to a possible application of DEP formed EBs in the production of blood-based products from ESCs.