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Agenesis of the dorsal pancreas is a rare congenital pancreatic malformation. We herein describe a 67-year-old woman with a 5-day history of lower back pain who was eventually diagnosed with agenesis of the dorsal pancreas. Abdominal computed tomography showed an enlarged pancreatic head, but the pancreatic body and tail were invisible. The magnetic resonance imaging findings were similar to the computed tomography findings. Magnetic resonance cholangiopancreatography showed that the major pancreatic duct was mildly dilated but otherwise normal. Endoscopic ultrasound revealed absence of the pancreatic body and tail, an enlarged head of the pancreas, and mild pancreatic duct dilation. The final diagnosis was dorsal pancreatic agenesis.

This paper studied the photocatalytic reduction kinetics of bromate in aqueous dispersion of TiO2 and investigated the effects of experimental parameters, including initial concentration of BrO3-, pH, TiO2 dosage, anion and cation. The results indicate that the process of photocatalytic reduction of bromate follows a zero-order kinetics. In all the investigated experimental parameters, the initial bromate concentration, pH and anion have great effect on the photocatalytic reduction kinetics. The processes of photocatalytic reduction of bromate show the pseudo first-order kinetics at initial bromate concentration of 0.39 μmolL-1, pH=5.0, or in presence of HCO3-/CO32-, NO3-, SO42-, respectively.

Multiwall carbon nanotubes (CNT) were added into ZnO matrix to develop a CNTs/ZnO composite gas sensor. The hybrid sensor is used to detect CO in air by measuring resistance changes of thin CNTs/ZnO films at different working temperature. For comparison, pure ZnO and CNT/ZnO sensors are also examined. The gas sensing results reveal that CNTs/ZnO with the weight ratio (9:100) hybrid sensors exhibit much higher sensitivity and fast response-recovery properties towards CO, at 240°C than the blank ZnO nanowires. Hybrid material of ZnO nanowires and CNT composites could potentially display not only the unique properties of nanowires and those of CNTs, but also an additional novel property.

Two novel one-dimensional coordination polymers, single helicate [Zn(SPh){sub 2}(TPyTA)(EG)]{sub n} (EG=ethylene glycol) (1) and zig-zag structure [Zn(SPh){sub 2}(BPyVB)]{sub n} (2), were synthesized under solvothermal conditions at 150 Degree-Sign C or room temperature by the co-assembly of Zn(SPh){sub 2} and organic linkers such as 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPyTA) and 1,3-bis(trans-4-pyridylvinyl)benzene (BPyVB). X-ray crystallography study reveals that both polymers 1 and 2 crystallize in space group P2{sub 1}/c of the monoclinic system. The solid-state UV-vis absorption spectra show that 1 and 2 have maxium absorption onsets at 400 nm and 420 nm, respectively. TGA analysis indicates that 1 and 2 are stable up to 110 Degree-Sign C and 210 Degree-Sign C. - Graphical abstract: Two novel one-dimensional coordination polymers, single helicate [Zn(SPh){sub 2}(TPyTA)(EG)]{sub n} (1) and zig-zag structure [Zn(SPh){sub 2}(BPyVB)]{sub n} (2), were synthesized. Solid-state UV-vis absorptions show that 1 and 2 have maxium absorption onsets at 400 nm and 420 nm, respectively. TGA analysis indicates that 1 and 2 are stable up to 110 Degree-Sign C and 210 Degree-Sign C. Highlights: Black-Right-Pointing-Pointer Two novel one-dimensional coordination polymers have been synthesized. Black-Right-Pointing-Pointer TPyTA results in helical structures in 1 while BPyVB leads to zig-zag chains in 2. Black-Right-Pointing-Pointer Solid-state UV-vis absorption spectra and TGAmore » analysis of the title polymers were studied.« less

We demonstrate the synthesis of a three-layer-coaxial SnO2/ZnSn2O4/ZnO core–shell nanocable heterostructures with diameters 80-150 nm via thermal oxidation of Zn and Sn mixture powders. The products are characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and field emission transmission electron microscopy (TEM). The structural analysis shows the formation of ZnSnO4 in the interface region between the SnO2 core and ZnO shell, which is resulted from inter－diffusion of Sn and Zn ions during thermal evaporation. The selected area electron diffraction (SAED) pattern was composed of two series of overlapped polycrystalline rings attributed to SnO2 and Zn2SnO4, one set of hexahedron diffraction spots that can be indexed to the hexagonal ZnO. On the basis of investigation of the microstructures, the possible formation mechanism of Zn2SnO4 is discussed.

A simple controllable method is reported for the coating of ZnO nanowires with Ag nanoparticles and ZnO/carbon nanotubes (CNTs) composite. It has been achieved through DC electrophoresis AgNO 3 electrolyte and CNTs in the presence of isopropanol dispersion of ZnO nanowires. In the present work, the influence of Ag nanoparticles and CNTs on the field emission properties of the composite materials is studied. The results of this research demonstrate a remarkable enhancement of field emission current of ZnO nanowires in case of CNTs mixture and Ag nanoparticles coating.

From atomic level to understand the cluster-size-dependant behavior of dye-sensitized photocatalysts is very important and helpful to design new photocatalytic materials. Although the relationship between the photocatalytic behaviors and particles' size/shape has been widely investigated by theoretical scientists, the experimental evidences are much less. In this manuscript, we successfully synthesized three new ruthenium dye-sensitized polyoxometalates (POM-n, n relate to different size clusters) with different-sized POM clusters. Under visible-light illumination, all three complexes show the stable O 2 evolution with the efficient order POM-3 > POM-2 > POM-1. This cluster-size-dependent catalytic behavior could be explained by the different numbers of M = Ot (terminal oxygen) bonds in each individual cluster because it is well-known that Mo = Ot groups are the catalytically active sites for photooxidation reaction. The proposed mechanism of water oxidation for the dye-sensitized POMs is radical reaction process. This research could open up new perspectives for developing new POM-based WOCs. Published version

To solve the problem that Various post-treatment technologies were needed to improve the field emission in the current preparation of screen printing carbon nanotubes (CNTs) film, a novel pulping process without post-treatment for screen printing ZnO nanoneedles was presented. Carboxymethyl cellulose (CMC) was used for pulping agent and water was used for dissolvent in this process. The measurement of field emission revealed that the ZnO nanoneedles film prepared by mass ratio 3:5 of ZnO nanoneedles to the paste agent had the lowest turn-on field 2.25V/μm at the current density of 1μA/cm2 , and the uniform distribution and great density of luminance points of the ZnO nanoneedles was obtained at the applied field of 4V/μm. This method had a good utility value in the fabrication of ZnO nanoneedles field emission display.Copyright © 2008 by ASME

Adjacent natural teeth with untreated pulpal or periodontal pathology may be a potential risk for implant infection. We report a rare case of an implant periapical lesion (IPL) possibly caused by direct extension of a periradicular lesion of an adjacent tooth. A 40-year-old female patient, who had previously received three implants on the edentulous areas of teeth 16, 36 and 46, had a recurrent infection over the lower left second molar area for 2 years. A periapical radiograph revealed incomplete root canal treatment and an infrabony defect on the mesial side of the lower left second molar; the defect extended to the apical third of the adjacent implant on tooth 36. Open flap debridement was performed 1 year after implant placement, but pain and swelling persisted for another year. Therefore, the second molar was extracted at the patient's request. The patient was unable to seek earlier and prompt treatment as she was abroad; therefore, we were able to observe the progression of severity in the IPL. One year after the extraction, the symptoms had subsided, and a periapical radiograph showed that the radiolucent lesion had decreased in size. She was followed for another 1.5 years and showed marked improvement. In this case, the IPL probably originated from the endodontic-periodontic problem of the adjacent molar, and the infected implant was saved by removing the infection source. We also discuss the treatment and prognosis of IPLs. To prevent the occurrence of an IPL, it is important to evaluate the pulpal and periodontal status of the teeth near the implant site when making a comprehensive treatment plan for an implant.