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Apoptosis or programmed cell death is the result of complex biochemical and genetic signals triggered by normal physiological events or by exposure to toxic compounds. Apoptosis can be revealed early in cells and tissues due to morphological and biochemical alterations of the cell. Here, we review recent progress in the study of the induction and detection of apoptosis in zooplankton copepods after their exposure to different apoptotic-inducer compounds, and we propose methods to predict copepod mortality even when animals appear normal. We also discuss the use of higher harmonic generation microscopy and multiphoton fluorescence microscopy techniques as possible tools to visualize apoptosis in vivo copepods without using any fluorescent probes.

A general form used for analyzing residual stresses measured using the holographic blind-hole method is introduced in this paper. Adopting the general form presented, the residual stresses can be obtained using three relative displacements measured from a single interference fringe pattern. Even for the case in which phase-shifting holographic interferometry is not employed, interpolating calculations for determining the fringe orders are not needed, since the choice of data points becomes more flexible when using this general form. Two experiments, the first one carried out by the authors and the second one published previously, are used to illustrate the applicability and usefulness of this general form. Suggestions for the applications of this general form are also established via the upper bound error estimations.

The relationship between the displacements and stresses relieved from blind-hole drilling is introduced via an easily understandable concept in this paper. Combining this concept with holographic interferometry, two holographic blind-hole methods for measuring residual stresses are established. The first is a new technique which requires measuring three out-of plane displacements; and the second is a modification of another technique which requires measuring two out-of plane displacements. Each of the two methods needs only one interference fringe pattern and is demonstrated by using it to measure a known residual stress in an aluminum specimen.

The authors discuss critical aspects of imaging system design and describe several different imaging systems employing focal plane array receivers operating in the 3-mm-2-mm wavelength range. Recent progress in millimeter-wavelength optics, antennas, receivers and other components permits greatly enhanced system performance in a wide range of applications. A radiometric camera for all-weather autonomous aircraft landing capability and a high sensitivity cryogenically cooled array for use in radio astronomical spectroscopy are presented. A near-focus system for identification of plastic materials concealed underneath clothing employs a two element lens, and has been demonstrated in active (transmitting) and passive (radiometric) modes. A dual-mode imaging system for plasma diagnostics utilizes both active and passive modes at its approximately=140-GHz operating frequency to study small-scale structure. The radiometric imaging systems employ between 15 and 256 Schottky barrier diode mixers, while the imaging receivers for the active systems include 64-element video detector arrays. >

This paper proposes an identification scheme of capacitor switching transients using Approximate Entropy (ApEn) approach. Detailed procedures of the proposed scheme are presented. Simulation and real results indicated that the scheme is feasible for classification of power event signals.

In this paper, a complex continuous wavelet transform (CWT)-based entropy method is proposed to enhance the damage-detection capability of wind turbine blades. By embedding the time-frequency localization features in wavelets, wavelet entropy of acquired signals can be readily computed. This approach can form a quantitative index systematically to detect the damage of blades, anticipating formulating a forewarning mechanism for wind power system. Test results demonstrated the practicality and advantages of the method for the application considered.

This paper proposes an active clamp interleaved forward converter with a single-capacitor turn-off snubber constructed with a full-bridge inverter for stunning poultry applications. The proposed converter can use active clamp circuit to recover the energy trapped in magnetizing and leakage inductors of transformer and to achieve zero-voltage switching at turn-on transition. In addition, the proposed one adopts a single-capacitor snubber not only to smooth out switch voltage at turn-off transition for reducing switching loss but to decrease the ringing voltage across output freewheeling diodes of the proposed converter at turn-on transition of each switch. As compared with the counterparts of the conventional converter topologies, the proposed converter has the merits of less component counts, higher efficiency, smaller size, and they are easier to implement Performance measurements from a prototype have verified feasibility of the overall system design. This designed system has contributed a lot of humane slaughter and has attracted much attention.

This paper proposes an interleaved flyback converter with a novel L-C-D snubber to reduce turn-on and turn-off losses. The proposed L-C-D snubber is composed of a single capacitor to form turn-off snubber, and an inductor and a diode connected in parallel to form turn-on snubber. In this circuit structure, the turn-off snubber is used to limit rising rate of drain-source voltage of MOSFET and to reduce turn-off switching loss. While, the turn-on ones are used to smooth out current passing switch and to reduce turn-on switching loss. In addition, the proposed converter is operated in an interleaved fashion to reduce output current ripple. Compared with the counterparts of conventional converter topologies, the proposed converter has the merits of less component counts, higher efficiency, small size, and they are easier to implement. Measured results obtained from a prototype flyback converter have verified the feasibility.

The paper proposes an active clamp interleaved flyback converter with a single-capacitor turn-off snubber associated with a full-bridge inverter for stunning poultry applications. The proposed converter can use active clamp circuit to recover the energy of transformer and to achieve zero-voltage switching at turn-on transition. In addition, the proposed one adopts a single-capacitor snubber not only to smooth out switch turn-off transient for reducing turn-off loss but to reduce the ringing voltage of diodes in secondary winding of transformer when switch of the proposed one is operated at turn-on transition. Compared with the counterparts of the conventional converter topologies, the proposed converter has the merits of less component counts, higher efficiency, smaller size, and they are easier to implement. Performance measurements from a prototype have verified feasibility of the overall system design. This designed system has contributed a lot of humane slaughter and has attracted much attention.

Production of a monoenergetic electron bunch in a self-injected laser-wakefield accelerator is investigated with a tomographic method which resolves the electron injection and acceleration processes. It is found that all the electrons in the monoenergetic electron bunch are injected at the same location in the plasma column and then accelerated with an acceleration gradient exceeding 2 GeV/cm. The injection position shifts with the position of pump-pulse focus, and no significant deceleration is observed for the monoenergetic electron bunch after it reaches the maximum energy. The results are consistent with the model of transverse wave breaking and beam loading for the injection of monoenergetic electrons. The tomographic method adds a crucial dimension to the whole array of existing diagnostics for laser beams, plasma waves, and electron beams. With this method the details of the underlying physical processes in laser-plasma interactions can be resolved and compared directly to particle-in-cell simulations.

This paper proposes an interleaved boost converter with a novel L-C-D snubber to reduce turn-on and turn-off switching losses. The proposed L-C-D snubber is composed of a single capacitor to form turn-off snubber, and an inductor and a diode connected in parallel to form a turn-on snubber. In this circuit structure, the turn-off snubber is used to limit rising rate of voltage across switch of the proposed converter and to reduce turn-off switching loss. While, the turn-on ones are used to smooth out current through switch of the proposed one and to reduce turn-on switching loss. Furthermore, the proposed converter is operated in an interleaved fashion to reduce output current ripple. Compared with the counterparts of conventional converter topologies, the proposed converter has merits of less component count, higher efficiency, smaller size, and they are easier to implement. Hardware measurement obtained from experimental prototype has been verified these merits.

This paper presents an LED lighting system with PV sources. The circuit of the proposed system adopts buck-boost converter associated with flyback converter to charge battery and to drive an LED lighting system. In this research, buck-boost converter is used as a charger for charging battery, and flyback converter with active clamp circuit is adopted to drive the LED lighting. To simplify the circuit structure, switches of two converters are integrated with a synchronous switch technique. With this approach, the proposed system has several merits, which are a less component count, lighter weight, smaller size and higher conversion efficiency. Compared with the conventional converter with hard-switching circuit, the proposed one can improve conversion efficiency of 5% and achieve efficiency about 83% under full load at driving the LED lighting. Experimental results obtained from a prototype with output voltage of 10 V and output power of 20 W have verified its feasibility.

A tomographic method based on laser machining was used to resolve the electron injection and acceleration processes in a laser wakefield accelerator. It was found that all the electrons in the monoenergetic electron beam are injected at the same location in the plasma column and then accelerated with an acceleration gradient exceeding 2 GeV/cm. In addition, it was observed that there is no significant deceleration of the monoenergetic electron bunch after reaching the maximum energy and the injection position shifts with change of the position of pump‐pulse focus. The results are consistent with the model of transverse wave‐breaking and beam loading for injection of monoenergetic electrons. With this method the details of the underlying physical processes in a laser wakefield accelerator can be resolved and compared directly to the observations in particle‐in‐cell simulations.