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For an electron-optical imaging system with wide beam focusing, the calculation of the field curvature can be performed only theoretically and requires the specific analytical expressions of the axial potential distribution in the streak tube and its corresponding derivatives, making the calculation cumbersome. Even when the electron trajectory is tracked using the numerical calculation method, the calculated results cannot be verified experimentally. A method for measuring the field curvature of the streak tube based on the spherical fluorescent screen is proposed for the first time, to the best of our knowledge. This method can directly measure the field curvature from the experimental image without requiring information on the internal structure of the streak tube, which is extremely useful for the design of the subsequent image reconstruction algorithm.

In this paper, an eighth order combined compact finite difference scheme was presented. Through Fourier analysis and numerical tests, one can find that the scheme has spectral-like resolution, and proved to be an ideal class of schemes for the calculation of high order derivatives calculation of electrostatic field in image tube.

Glycation product accumulation during aging of slowly renewing tissues may be an important mechanism underlying aging of the testis. Adipose-derived stem cells (ADSCs) have shown promise in a novel tissue regenerative technique and may have utility in treating sexual dysfunction. ADSCs have also been found to be effective in antiaging therapy, although the mechanism underlying their effects remains unknown. This study was designed to investigate the anti-aging effect of ADSCs in a D-galactose (D-gal)–induced aging animal model and to clarify the underlying mechanism. Randomly selected 6-week-old male Sprague–Dawley rats were subcutaneously injected with D-gal daily for 8 weeks. Two weeks after completion of treatment, D-gal–induced aging rats were randomized to receive caudal vein injections of 3 × 106 5-bromo 2′deoxy­uridine–labeled ADSCs or an equal volume of phosphate-buffered saline. Serum testosterone level, steroidogenic enzymes (3-β-hydroxysteroid dehydrogenase), and superoxide dismutase (SOD) activity decreased significantly in aging rats compared with the control group; serum lipid peroxidation, spermatogenic cell apoptosis, and methane dicarboxylic aldehyde (MDA) expression increased significantly. ADSCs increased the SOD level and reduced the MDA level in the aging animal model and restored levels of serum testosterone, steroidogenic enzymes, and spermatogenic cell apoptosis. These results demonstrate that ADSCs can contribute to testicular regeneration during aging. ADSCs also provide functional benefits through glycation suppression and antioxidant effects in a rat model of aging. Although some ADSCs differentiated into Leydig cells, the paracrine pathway seems to play a main role in this process, resulting in the reduction of apoptosis. J. Cell. Physiol. 230: 2403–2414, 2015. © 2015 Wiley Periodicals, Inc.

The anatomical basis for the concept of acupuncture points/meridians in traditional Chinese medicine (TCM) has not been resolved. This paper reviews the fascia research progress and the relationship among acupuncture points/meridians, primo vascular system (PVS), and fascia. Fascia is as a covering, with common origins of layers of the fascial system despite diverse names for individual parts. Fascia assists gliding and fluid flow and holds memory and is highly innervated. Fascia is intimately involved with nourishment of all cells of the body, including those of disease and cancer. The human body’s fascia network may be the physical substrate represented by the meridians of TCM. The PVS is a newly found circulatory system; recent increased interest has led to new research and new discoveries in the anatomical and functional aspects of the PVS. The fasciology theory provides new insights into the physiological effects of acupuncture needling on basic cellular mechanisms including connective tissue mechanotransduction and regeneration. This view represents a theoretical basis and means for applying modern biomedical research to examining TCM principles and therapies, and it favors a holistic approach to diagnosis and treatment.

Glycation product accumulation during aging of slowly renewing tissues may be an important mechanism underlying aging of the testis. Adipose-derived stem cells (ADSCs) have shown promise in a novel tissue regenerative technique and may have utility in treating sexual dysfunction. ADSCs have also been found to be effective in antiaging therapy, although the mechanism underlying their effects remains unknown. This study was designed to investigate the anti-aging effect of ADSCs in a D-galactose (D-gal)-induced aging animal model and to clarify the underlying mechanism. Randomly selected 6-week-old male Sprague-Dawley rats were subcutaneously injected with D-gal daily for 8 weeks. Two weeks after completion of treatment, D-gal-induced aging rats were randomized to receive caudal vein injections of 3 × 10(6) 5-bromo 2'deoxy-uridine-labeled ADSCs or an equal volume of phosphate-buffered saline. Serum testosterone level, steroidogenic enzymes (3-β-hydroxysteroid dehydrogenase), and superoxide dismutase (SOD) activity decreased significantly in aging rats compared with the control group; serum lipid peroxidation, spermatogenic cell apoptosis, and methane dicarboxylic aldehyde (MDA) expression increased significantly. ADSCs increased the SOD level and reduced the MDA level in the aging animal model and restored levels of serum testosterone, steroidogenic enzymes, and spermatogenic cell apoptosis. These results demonstrate that ADSCs can contribute to testicular regeneration during aging. ADSCs also provide functional benefits through glycation suppression and antioxidant effects in a rat model of aging. Although some ADSCs differentiated into Leydig cells, the paracrine pathway seems to play a main role in this process, resulting in the reduction of apoptosis.

A transmission framing electron microscope which consists of a lanthanum hexaboride cathode, two focusing lenses, an object lens, an intermediate lens, a projective lens, a scan deflector, a two-aperture-plate, a two compensation deflectors, a fiber plate based phosphor screen, an image intensifier, and a CCD readout system, is constructed based on a DX-4 transmission electron microscope. Two framing micrographs each in the size of (phi) 10 mm, with magnification of 10,000 have been obtained. Under the current condition, the exposure time of 43 ns (FWHM is 21.5 ns) has been achieved. The spatial resolution is evaluated by edge spread function and is proved to be 14.4 nm limited by the CCD readout system. Apart from the technical problems, the physical limitation and the potential of the framing electron microscopy are discussed, indicting that the temporal resolution of 100 ps and the spatial resolution of 10 nm can be achievable. The experimental results and the analysis show the potential of the application of the framing electron microscopy in the related research area.

A new kind of long slit soft x-ray streak camera is presented in this paper. Typical performances of the system have been characterized by broad soft x-ray beam ranging from 100 ev to 10 Kev. With a slit length of 30 mm, this camera can record simultaneously all the soft x-ray spectrum ranging from 30 angstroms to 180 angstroms with high spatio- temporal resolution. Time distortion of the camera is minimized by improving the design of the electron-optical system of the soft x-ray streak tube. Special measures have been taken to eliminate the effect of the dynamic deflection field on the focusing system and to improve the dynamic spatial resolution. With demountable photocathode and mesh, this camera can be operated under various conditions. A special vacuum system is designed to meet the needs of the camera to operate independently of the experimental chamber. Dynamic tests show that the camera has a temporal resolution of 5 ps and a spatial resolution of 15 Lp/mm along the slit length of 30 mm at the required speed of 2.5 cm/ns. The residual time distortion has been corrected in order to give initial time for each spectrum correctly.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The framing image tube camera has some intrinsic advantages. It has got some applications in ICF and X-ray laser field. But there are two main problems with this technique: the loss of spatial resolution at short exposure time,a nd the electromagnetic disturbance in the experimental area. In order to solve these problems, we have taken several measures: to improve the design of the image tube and the electronics and to strengthen the shielding. Additionally, in intense X-ray pulse we use MgF2 as cathode material instead of Au and CsI to reduce the space charge effects. The experiments in high power laser area have shown that 3 frame images can be provided with 75 ps (FWHM) exposure time and dynamic spatial resolution of 6 lp/mm. Some physics results of high power laser-plasma interaction have also been obtained.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper a universal streak camera will be introduced. This camera consists of time distortion-compensated optical lens, vacuum ultraviolet-sensitive streak image tube, multifunction sweep circuits and CCD real-time readout system. It can work in 3 modes, including single shot, synchroscan and dual scan. This camera can also work in circular scan mode. The temporal resolution of 1.2 ps can be achieved in single shot mode. The operation frequency can be 82 MHz, 164 MHz, 200 MHz and 300 MHz for synchroscan and circularscan modes. In this case, the temporal resolution is operation frequency dependent, usually in the range of 1-3 ps. In dual scan operation mode, one deflector is driven by sine wave circuit, another by a slow ramp circuit. The scan speed along the fast and slow axis is 5 cm/ns and 26 cm/microsecond(s) -2 cm/microsecond(s) .

The characteristics, including temporal resolution, dynamic range, and time distortion, of our femtosecond streak image tube developed a few years ago have been examined systematically by experiments under different conditions. It can be concluded from the experiments: (1) in order to achieve a temporal resolution of less than 400 fs with acceptable fluctuation the travelling wave deflection system and specially processed photocathode have played an important role, (2) to expand the dynamic range and to stabilize the temporal resolution it is of importance to minimize the noise and to accumulate the signal along the slit, (3) to accomplish above signal accumulation along the slit the time distortion has to be eliminated, which could be realized by using our specially designed optical lens. The aim of this study is to improve the temporal resolution up to 50 - 100 fs by a newly designed femtosecond streak image tube.