chestnut-leaved oak (quercus castaneifolia) is one of the most important industrial species of the northern forests of iran. regeneration of this valuable species is limited due to several problems such us pests and the fungal diseases. in order to isolate and identify the fungi associated with oak seed, sampling was carried out during 2007 in shast-kalate forest at gorgan. collected seeds were...

Background:The diagnostic accuracy of frozen section as an important source of information in surgical pathology is important not only in the management of surgical patients but also as a measure of quality control in surgical pathology. In this study, we evaluated the diagnostic accuracy of frozen sections over a 6-year period in a teaching hospital in Iran. Methods: We retr...

One of the most efficient lighting technology is based on light-emitting diodes (LEDs). Common LED drivers with AC-input (50-60Hz) usually require a bulk electrolytic capacitor to decrease low-frequency ripple in the output. However, the critical element that limits the lifespan of the LED driver is the electrolytic capacitor. An isolated off-line LED driver is proposed in this paper, in which ...

The bandwidth and performance of optical phase-lock loops (OPLLs) using single-section semiconductor lasers (SCLs) are severely limited by the nonuniform frequency modulation response of the lasers. It is demonstrated that this restriction is eliminated by the sideband locking of a single-section distributed-feedback SCL to a master laser in a heterodyne OPLL, thus enabling a delay-limited loop...

background:the diagnostic accuracy of frozen section as an important source of information in surgical pathology is important not only in the management of surgical patients but also as a measure of quality control in surgical pathology. in this study, we evaluated the diagnostic accuracy of frozen sections over a 6-year period in a teaching hospital in iran. methods: we retrospectively review...

In this chapter, we take a different approach. In Section 2, we analyze the basics of analog subtractive synthesis, using the simple patch of a square-wave oscillator processed by a low-pass filter with a dynamically variable cutoff frequency. In Section 3, we show how a single mathematical function can model both the oscillator and filter together, and describe an efficient formation for this ...