Identification of Markers that Distinguish Monocyte-Derived Fibrocytes from Monocytes, Macrophages, and Fibroblasts

The processes that drive fibrotic diseases are complex and include an influx of peripheral blood monocytes that can differentiate into fibroblast-like cells called fibrocytes. Monocytes can also differentiate into other cell types, such as tissue macrophages. The ability to discriminate between monocytes, macrophages, fibrocytes, and fibroblasts in fibrotic lesions could be beneficial in identifying therapies that target either stromal fibroblasts or fibrocytes. and in sections from human lung. We found that markers such as CD34, CD68, and collagen do not effectively discriminate between the four cell types. In addition, IL-4, IL-12, IL-13, IFN-γ, and SAP differentially regulate the expression of CD32, CD163, CD172a, and CD206 on both macrophages and fibrocytes. Finally, CD49c (α3 integrin) expression identifies a subset of fibrocytes, and this subset increases with time in culture.These results suggest that discrimination of monocytes, macrophages, fibrocytes, and fibroblasts in fibrotic lesions is possible, and this may allow for an assessment of fibrocytes in fibrotic diseases

Tail Current Noise Suppression in RF CMOS VCOs

This paper presents the experimental results of two different techniques, inductive degeneration and capacitive filtering, for reducing the phase noise in tail-biased RF CMOS voltage-controlled oscillators (VCOs). Both techniques prevent the low-frequency tail current noise from being converted into phase noise. The techniques are applied to two distinct VCO designs, showing that the largest phase noise reduction (up to 6-7 dB at 3-MHz offset frequency from the carrier) is achieved via inductive degeneration. Capacitive filtering, however, also substantially reduces the phase noise at high offset frequencies and may therefore become a valid alternative to inductive degeneration, as discrete capacitors are of more common use than discrete inductors

A Class-AB 1.65GHz-2GHz Broadband CMOS Medium Power Amplifier

In this paper a single stage broadband CMOS RF power amplifier is presented. The power amplifier is fabricated in a 0:25¹m CMOS process. Measurements with a 2:5V supply voltage show an output power of 18:5 dBm with an associated PAE of 16% at the 1-dB compression point. The measured gain is 5.1 § 0:5 dB from 1.65 to 2 GHz. Simulated and measured results agree reasonably well

850/900/1800/1900MHz Quad-Band CMOS Medium Power Amplifier

This paper presents a two-stage quad-band CMOS RF power amplifier. The power amplifier is fabricated in a 0.25 mum CMOS process. The measured 1-dB compression point between 800 and 900 MHz is 15 dBm plusmn 0.2 dB with maximum 18% PAE, and between 1800 and 1900MHz is 17.5dBm plusmn 0.7dB with maximum 17% PAE. The measured gains in the two bands are 23.6 dB plusmn 0.7 dB and 13 dB plusmn 2.1 dB, respectively

High-resolution passive phase shifters for adaptive duplexing applications in SOS process

Two high-resolution passive delay line phase shifters in silicon-on-sapphire are compared. Both make use of digitally tuned capacitor loaded π sections to obtain 360° phase control. The first has a nominal resolution of 9-bit and uses ten sections, yielding an insertion loss (IL) of 12.6 dB at 1.4 GHz. The second employs a center tapped auto-transformer to provide 180° of phase shift, reducing both size and the IL while enabling a further 1-bit improvement in resolution. The measured IL in the 1.8-2.4-GHz frequency range is less than 7.3 dB. Stacked field-effect transistors were employed as switches to increase the power-handling capability. An input referred third intercept point (IIP3) of + 39 and + 54 dBm were measured for the first and second circuits, respectively. © 2014 IEEE