The portable high frequency (HF) X-ray machine for field use is introduced in this paper, which applies HF technology and the microcomputer. Compared with the traditional one, it has many new functions such as the self-motion exposal, real-time inspection and display, the alarm of the failure and the automatic disposal. With the advanced technology, it has overcome the deficiencies of the traditional one, including the overweight, bulkiness and unportability. Equipped with the portable mobile shelf, this machine is fit for field operations.

Basic and cIinicaI studies demonstrate that depression is associated with abnormaI neuraI pIasticity in some brain regions,incIuding the prefrontaI cortex and hippocampus. Brain-derived neurotro-phic factor(BDNF)and its signaIing pathways pIay a cruciaI roIe in reguIating neuraI pIasticity and deveI-opment of depression. Ketamine or scopoIamine can produce a quick and sustained antidepressant effect,and both can quictIy activate BDNF-signaIing pathways reIated to neuraI pIasticity. In order to pro-vide the theoreticaI basis for future researches on new antidepressants,the neuraI pIasticity mechanisms of faster-onset antidepressants are reviewed in this paper.

DICOM is an international standard in medical imaging and communication. This paper introduces the design of digital X-ray data storage and communication according to DICOM3.0 and emphasizes the implementation of such modules as the ones for communication and data storage.

Selection of CR and DR is very important for digital radiology departments in modern hospitals. This paper discusses the components of CR and DR as well as their technical requirements.

LabVIEW is applied to the realization of virtual oscilloscope, and such functions are fulfilled as waveform display, parameter measurement, filter, spectral analysis, data storage and playback.

Purpose:Cochlear implant is a sort of device which is used to restore normal heating for the profoundly deaf by electrical stimulation of the auditory nerve.Simulation of multiple channels demonstrates that the number of channels has significant influence on sound effect.Method:This paper reviews the Continuous Interleaved Sampling (CIS) strategy for cochlear implants,and simulates it in PC.The audible sound of cochlear implanter is synthesized,and preliminary analysis of the speech identification rate of CIS strategy in different channels has also been done based on the simulation.Result:CIS strategy using 6 or 8 channels can achieve better sound effect .Conclusion:Simulation results show that CIS strategy with envelope extraction and high number of channels can produce satisfactory speech synthesis effect

In this paper, the mobile stereotactic radiosurgical system, a new therapeutant for interstitial radiotherapy, is introduced. Its principle and initial clinical applications are also summarized

Objective To design and develop a high-volt generator for mobile photon radiation therapy system's X-ray tube. Methods With a 12V storage battery as the power supply, high-frequency switch circuit and CW voltage doubling rectifying circuit were adopted to generate high voltage. Results Its main circuit was tested by using a simulation software, and it could meet the desired requirements. Conclusion The circuit is simple and reliable, and thus can be miniaturized.

Objective To find a new algorithm for PET/CT image fusion.Methods A variational model was used based on the wavelet transform.Firstly,PET and CT images were decomposed using wavelet transform.Then,images in approximate channel and detail channel were fused according to the two proposed assumption.Finally,decomposed images were synthesized to form fused image.Results Compared with the results form MATLAB wavelet fusion toolbox,the experimental results showed that the new variational image fusion model could provide more accurate result for target location in radiotherapy planning.Conclusion According to experiments,the new algorithm can reach good results and meet requirement of clinical demands.

Objective To investigate the influence of respiratory motion on target dose distribution in three-dimensional conformal radiation therapy(3DCRT) and intensity modulated radiation therapy(IM-RT). Methods A 2D air vented ionization chamber array MatriXX system,a platform which can mimic the clip motion of lung tumor, and a home-made solid water(RW3) phantom were used to measure the 2D dose distribution of static and moving targets irradiated by 3DCRT and IMRT beams using multiple gantry an-gles. The period of the moving platform was set to 3.5 s and the amplitude was ± 1 cm. Then the differences of dose distribution between the static phantom and moving phantom were compared and analyzed with the MatriXX system software. Results Compared with the static phantom in 3DCRT, the penumbra of dose distribution of the periodic moving phantom along the moving directions was increased by 6-9 mm, the high dose area was shrinked by about 5 ram,and the low dose area was extended by 5 mm,but the area of 50% i-sodose and the dose center area changed very little. When a single segment beam of IMRT was delivered and measured and the maximum dose of measuring plane was normalized to 100% ,the average difference of dose distribution between the static and dynamic phantoms was ±27% (from -56.4% to 56.1%) ;When all of the segment beams of IMRT were dehvered and the integrated dose distribution was measured ,the dose differ-ences were less than ±3% ,and the maximum difference of dose distribution was about ±15% which mainly appeared at the field margin and were similar to 3DCRT. Conclusions The dose distribution of most cen-ter areas of the periodic moving target using multi-fraction 3DCRT/IMRT beams is similar to that of the static target, while the high dose area of the former is shrinked and the low dose area is extended.