Muscarinic acetylcholine receptors (mAChRs) have five distinct subunits (M1–M5) and are involved in the action of the neurotransmitter acetylcholine in the central and peripheral nervous system. Attributed to the promising clinical efficacy of xanomeline, an M1/M4-preferring agonist, in patients of schizophrenia and Alzheimer's disease, M1- or M4-selective mAChR modulators have been developed that target the topographically distinct allosteric sites. Herein we report the synthesis and preliminary evaluation of 11C-labeled positron emission tomography (PET) ligands based on a validated M4R positive allosteric modulator VU0467485 (AZ13713945) to facilitate drug discovery. [11C]VU0467485 and two other ligands were prepared in high radiochemical yields (>30 %, decay-corrected) with high radiochemical purity (>99 %) and high molar activity (>74 GBq μmol−1). In vitro autoradiography studies indicated that these three ligands possess moderate-to-high in vitro specific binding to M4R. Nevertheless, further physiochemical property optimization is necessary to overcome the challenges associated with limited brain permeability. 相似文献
A new hybrid coding method for transmitting videoconferencing images at a bit rate 384 kbits/s is proposed. Considering the characteristics of motion-compensated interframe prediction errors for typical videoconferencing scenes, a filter is introduced to separate pulsive components on which conventional discrete cosine transform (DCT) coding method does not work well. These separated pulsive components are coded by using scalar quantization (SQ). The remainder are DCT coded. For DCT coefficients, an adaptive coding method based on the classification of DCT coefficients is applied in order to improve the coding performance. Since the proposed method employs both DCT coding and SQ of prediction errors, it is named "DCT/SQ coding method." Experimental results show that the DCT/SQ coding method is effective to reduce so-called mosquito effects, and thus it can improve the quality of decoded images. 相似文献
In stand-alone photovoltaic (PV) systems, when the battery is fully charged, the excess generated power is wasted. To solve the problems of wasted excess power, a distributed flexible network photovoltaic (DFNPV) system is studied. It incorporates many PV subsystems each consisting of PV panel, DC/DC converter, and load, and are connected to each other with shared batteries. The excess generated power of the subsystem is transferred between PV subsystems to compensate the lack of power in other subsystems.The control method of transferring power is based on simple voltage control of the subsystems. The output voltage in a given subsystem decreases if a transient excessive load is larger than the generated power; as a result excess power is transferred from another subsystem that has sufficient power and higher voltage output. In this study, this proposed operation method is demonstrated by simulation of power transfer between two subsystems and among four subsystems. Furthermore, to estimate the size of the DFNPV system within an acceptable voltage drop, the relationships between cable length, power loss, and cable types are discussed. 相似文献
We propose a novel image sensor which has compression function on its sensor plane. The image compression sensor can significantly reduce the amount of pixel data output from the sensor. The proposed sensor is intended to overcome the communication bottle neck for high pixel rate imaging such as high frame rate imaging and high resolution imaging.
The compression algorithm is based on conditional replenishment. It detects motion and encodes only the pixels in moving areas. We have been investigating pixel parallel and column parallel architectures of the image compression sensor. In this paper, we present the column parallel architecture of the proposed sensor. In this architecture, fill factor and power dissipation are comparable to conventional MOS sensors in spite of integration of the processing circuits. We have fabricated a prototype chip based on the column parallel architecture. We describe the circuit and layout design and the results of some experiments using the prototype. 相似文献
BACKGROUND/AIMS: Close observation and evaluation of the function of the transposed stomach after esophagectomy is essential. The present study uses the sulfamethizole capsule meal test to evaluate differences in gastric emptying between the anterior and posterior mediastinal approaches in patients undergoing esophagectomy. METHODOLOGY: Thirty-eight patients who underwent the esophagectomy and esophagogastrostomy for esophageal cancer were randomly divided into 2 groups: Group 1: anterior mediastinal approach, and Group 2: posterior mediastinal approach. Gastric emptying was studied using the sulfamethizole capsule meal test. Patients received sulfamethizole food capsules, 65 g of bread, and 150 ml of water. Plasma sulfamethizole levels were determined by high performance liquid chromatography (HPLC). RESULTS: Gastric emptying in both groups was significantly accelerated compared to healthy volunteers. Gastric emptying did not differ significantly between groups 1 and 2. CONCLUSIONS: The present data show that the sulfamethizole capsule meal test is an effective means of evaluating the emptying of the transposed stomach. Furthermore, when the stomach is used as an esophageal substitute following esophagectomy, gastric emptying does not differ according to the access route. 相似文献
Low-driving-current temperature-stable 10 Gbit/s direct modulation was achieved for optimised 200 mum-long short cavity 1.3 mum p-doped quantum dot lasers. Driving conditions were 25.2 mAp-p for the modulation current and 23.4 mA for the bias current through the whole temperature range from 20 to 90degC 相似文献
Low threshold current operation of self-assembled InAs/GaAs quantum dot lasers grown by metal organic chemical vapour deposition is reported. Continuous-wave lasing at room temperature with low threshold current (6.7 mA) was achieved at the wavelength of 1.18 /spl mu/m. The threshold current of 6.7 mA is the lowest value so far achieved in quantum dot lasers grown by metal organic chemical vapour deposition. Comparison with photoluminescence spectra indicates that the observed lasing originates from the ground state of InAs quantum dots. 相似文献
Seventy-eight patients, aged 12-87 years, with osteoarthritis or extremity trauma, attached one indomethacin patch (containing 96 mg indomethacin) to the most symptomatic site twice daily. The final overall treatment outcome was excellent in 52% of the osteoarthritic patients and in 82% of the trauma patients, good in 27% and 13%, and fair in 3% and 0%, respectively. Side effects were reported by 4% of the patients. It is concluded that indomethacin-containing patches were effective and well-tolerated for the treatment of osteoarthritis and extremity trauma. 相似文献
The structural change of carbon aerogels at high temperatures up to 2800°C has been investigated. Change in microtexture of fine particles, which constitute carbon aerogels derived from phenolic resin, was of a typical non-graphitized carbon. The microporosity decreased with an increase of heat-treatment temperature, and disappeared at 2000°C. The mesoporosity still remained even after heat-treatment up to 2800°C, though 50% of mesopore volume was lost because of the fusion of the particles with the change of carbon microtexture. 相似文献