A front-end ASIC for use with large-pixel array detectors
An Integrated Circuit (IC) readout chip with four channels arranged so as to receive input charge from the corners of the chip was designed for use with 5- to 7-mm pixel detectors. This Application Specific IC (ASIC) can be used for cold neutron imaging, for study of structural order in materials using cold neutron scattering or for particle physics experiments. The ASIC is fabricated in a 0.5-/spl mu/m n-well AMI process. The design of the ASIC and the test measurements made will be reported. Noise measurements will also he reported.
A discriminator with a current-sum multiplicity output for the PHENIX multiplicity vertex detector
A current output multiplicity discriminator for use in the front-end electronics (FEE) of the Multiplicity Vertex Detector (MVD) for the PHENIX detector at RHIC has been fabricated in the a 1.2-/spl mu/ CMOS, n-well process. The discriminator is capable of triggering on input signals ranging from 0.25 MIP to 5 MIP. The frequency response of the discriminator is such that the circuit is capable of generating an output for every bunch crossing (105 ns) of the RHIC collider. Channel-to-channel threshold matching was adjustable to /spl plusmn/4 mV. One channel of the multiplicity discriminator occupied an area of 85 /spl mu//spl times/630 /spl mu/ and consumed 515 /spl mu/W from a single 5-V supply. Details of the design and results from prototype device testing are presented.
An injectable and thermosensitive hydrogel: Promoting periodontal regeneration by controlled-release of aspirin and erythropoietin.
Periodontitis is an inflammatory disease induced by complex interactions between host immune system and plaque microorganism. Alveolar bone resorption caused by periodontitis is considered to be one of the main reasons for tooth loss in adults. To terminate the alveolar bone resorption, simultaneous anti-inflammation and periodontium regeneration is required, which has not appeared in the existing methods. In this study, chitosan (CS), β-sodium glycerophosphate (β-GP), and gelatin were used to prepare an injectable and thermosensitive hydrogel, which could continuously release aspirin and erythropoietin (EPO) to exert pharmacological effects of anti-inflammation and tissue regeneration, respectively. The releasing profile showed that aspirin and EPO could be continuously released from the hydrogels, which exhibited no toxicity both in vitro and in vivo, for at least 21 days. Immunohistochemistry staining and micro-CT analyses indicated that administration of CS/β-GP/gelatin hydrogels loaded with aspirin/EPO could terminate the inflammation and recover the height of the alveolar bone, which is further confirmed by histological observations. Our results suggested that CS/β-GP/gelatin hydrogels are easily prepared as drug-loading vectors with excellent biocompatibility, and the CS/β-GP/gelatin hydrogels loaded with aspirin/EPO are quite effective in anti-inflammation and periodontium regeneration, which provides a great potential candidate for periodontitis treatment in the dental clinic. Statement of Significance To terminate the alveolar bone resorption caused by periodontitis, simultaneous anti-inflammation and periodontium regeneration is required, which has not appeared in the existing methods. Here, (1) the chitosan (CS)/β-sodium glycerophosphate/gelatin hydrogels loaded with aspirin/erythropoietin (EPO) can form at body temperature in 5 min with excellent biocompatibility in vitro and in vivo; (2) The faster release of aspirin than EPO in the early stage is beneficial for anti-inflammation and provides a microenvironment for ensuring the regeneration function of EPO in the following step. In vivo experiments revealed that the hydrogels are effective in the control of inflammation and regeneration of the periodontium. These results indicate that our synthesized hydrogels have a great potential in the future clinical application.