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A smart two-photon fluorescent platform based on desulfurization–cyclization was developed by attaching rhodamine to a cyanine skeleton through the Knoevenagel reaction. Based on the platform, a CyRSN probe was rationally designed and synthesized, in which morpholinyl naphthalimide and modified rhodamine thiohydrazide were linked to form a structure of monothio-bishydrazide. The probe exhibits excellent two-photon properties toward Hg2+ under Ti:sapphire pulsed laser 800 nm irradiation, allowing the naked-eye signal and fluorescence “turn-on” signal at 746 nm to be obviously distinguished. The addition of Hg2+ to the probe ensured that the naphthalimide donor and modified rhodamine acceptor were connected with electronically conjugated bonds (1,2,4-oxadiazole). Hence, a typical TBET process took place, resulting in an increase of the modified rhodamine NIR emission at 746 nm by about 34-fold as well as a decrease of the naphthalimide emission at 540 nm and producing a colorimetric change from pale yellow to green. The chemodosimeter exhibits a stable response for Hg2+ over other metal ions with a detection limit of 1.91 × 10−7 M, high sensitivity, a rapid response time, and pH independence under neutral conditions (pH 6.0–10.0). In addition, the CyRSN probe was successfully applied in the detection and quantification of Hg2+ in water samples with satisfactory recovery results. [ABSTRACT FROM AUTHOR]

Hypochlorite serves as a significant antimicrobial agent in the human immune system, and its detection is of great importance. Herein, a novel near-infrared BODIPY-based ClO− fluorescent probe (NCS-BOD-OCH3) was designed and synthesized. The emission bands of NCS-BOD-OCH3 concentrated at 595 nm and 665 nm. Since the electron withdrawing group 1,3,4-oxadiazole was formed after the desulfurization reaction, the fluorescence intensity of NCS-BOD-OCH3 decreased significantly in THF/H2O (v/v, 1 : 1, buffered with 10 mM PBS pH = 7.4), which is visible to the naked eye with an obvious color change. NCS-BOD-OCH3 can realize the two-photon up-converted fluorescence emission. The low detection limit was calculated from the titration results, with the figure for NCS-BOD-OCH3/ClO− being 1.15 × 10−6 M. The result of living cell imaging experiment demonstrated that NCS-BOD-OCH3 can successfully detect ClO− in living cells and can serve as a NIR mitochondrial imaging agent. It is an excellent platform for developing NIR ClO− fluorescent probes. [ABSTRACT FROM AUTHOR]

Large scale cesium lead-halide (CsPbX 3 , X = Cl, Br, and I) perovskite films have become the basis of laser applications. Common fabrication methods such as spin-coating and thermal evaporation have a trade-off between high quality and low cost. Herein, we reported a facile method for preparing a large area homogeneous perovskite CsPbBr 3 film via a multiple centrifugal deposition and solvent annealing (MCDSA) method. This method is superior because it can control the thickness (180 nm to 880 nm) of the film, ensure the film is crack and pinhole free, has a large area (2.5 cm × 2.5 cm), and has a low surface roughness (a root mean square of 32 nm). Multiple times of centrifugation and solvent annealing in the MCDSA method are key to improving the quality of the film as well as the laser performance. With increased centrifugation cycles from one to four, the thickness of the film increases from 180 nm to 880 nm, leading to a decrease in the laser threshold from 18.1 μJ cm -2 to 14.2 μJ cm -2 and an increase in the gain coefficient from 78.5 cm -1 to 112.7 cm -1 . When solvent annealing is employed, the gain coefficient is further increased to 122.7 cm -1 ., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Aim: To investigate the feasibility and the effectiveness of ileoileostomy in the region adjacent to the ileocecal valve, which can retain the ileocecal valve in infants., Methods: This is a retrospective review of 48 patients who underwent ileoileostomy in the region adjacent to the ileocecal valve (group 1) and 34 patients who underwent ileocecal resections and ileotransversanastomosis (group 2). Patients were monitored for the time to flatus, resumption of eating, length of hospital stay after surgery, serum total bile acid, vitamin B12 and postoperative complications., Results: The time to flatus, time until resumption of eating and post-operative length of hospital stay showed no statistically significant differences between the two groups. Serum total bile acid and vitamin B12 were not significantly different between the two groups at post-operative day 1 and day 3, but were significantly decreased at 1 wk after operation in group 2. None of the patients died or suffered from stomal leak in these two groups. However, the incidence of diarrhea, intestinal infection, disturbance of acid-base balance and water-electrolytes in group 1 was lower than in group 2., Conclusion: Ileoileostomy in the region adjacent to the ileocecal valve is safe and results in fewer complications than ileotransversanastomosis in infants.

Daily ozone column densities were monitored by Passive DOAS (differential optical absorption spectroscopy) from December 10th, 2008 to Feb 19th, 2009 at Zhongshan Station, Antarctic (69 degrees 22'24" S, 76 degrees 22'14" E). Considering the absorption of O3, OClO, NO2, O4, BrO and the Ring effect, ozone slant column densities were retrieved using the zenith scattered sunlight as the light source. The results showed that there was no obvious "ozone hole" during the monitoring period, but ozone VCD (vertical column density) had greatly changed within short time scale, especially in middle December and early February. The analysis of passive DOAS and Brewer measurements of ozone VCD showed good agreement with the correlative coefficient of 0.863, while satellite board OMI measurements with the correlative coefficient of 0.840, which confirmed the validity of the monitoring of Passive DOAS.