The Coupling of Alternative Splicing and Nonsense-Mediated mRNA Decay

Most human genes exhibit alternative splicing, but not all alternatively spliced transcripts produce functional proteins. Computational and experimental results indicate that a substantial fraction of alternative splicing events in humans result in mRNA isoforms that harbor a premature termination codon (PTC). These transcripts are predicted to be degraded by the nonsense-mediated mRNA decay (NMD) pathway. One explanation for the abundance of PTC-containing isoforms is that they represent splicing errors that are identified and degraded by the NMD pathway. Another potential explanation for this startling observation is that cells may link alternative splicing and NMD to regulate the abundance of mRNA transcripts. This mechanism, which we call "Regulated Unproductive Splicing and Translation" (RUST), has been experimentally shown to regulate expression of a wide variety of genes in many organisms from yeast to human. It is frequently employed for autoregulation of proteins that affect the splicing process itself. Thus, alternative splicing and NMD act together to play an important role in regulating gene expression

Retention of data in heat-damaged SIM cards and potential recovery methods

Examination of various SIM cards and smart card devices indicates that data may be retained in SIM card memory structures even after heating to temperatures up to 450oC, which the National Institute of Standards and Technology (NIST) has determined to be approximately the maximum average sustained temperature at desk height in a house fire. However, in many cases, and certainly for temperatures greater than 450oC, the SIM card chip has suffered structural or mechanical damage that renders simple probing or rewiring ineffective. Nevertheless, this has not necessarily affected the data, which is stored as charge in floating gates, and alternative methods for directly accessing the stored charge may be applicable

A 3.3mW SigmaDelta modulator for UMTS in 0,18 μm CMOS with 70dB dynamic range in 2MHz bandwidth

The authors present a 4th-order continuous-time S¿ modulator with 1.5 b quantizer and feedback DAC for a UMTS receiver. The modulator has 70 dB DNR in a 2 MHz band and -74 dB THD at full scale. An IC which includes two modulators, a PLL, and an oscillator dissipates 11.5 mW at 1.8 V. Active area is 0.41 mm2 in a 0.18 µm, 1-poly 5-metal-layer CMOS technology