A hemispherical silicon solid immersion lens (SIL) was used to improve the spatial resolution of front-side thermal IR imaging in lock-in mode. The bottom of the SIL was cone-shaped to reduce the footprint of the SIL to the size of the imaged region. Caused by the lock-in operation mode, the detection limit improves by 2-3 orders of magnitude, and scattered light does not limit the image contra...

The polymerase chain reaction (PCR) has been an essential tool for diagnosis of infectious diseases, but conventional PCR still has some limitations with respect to applications to point-of-care (POC) diagnostic systems that require rapid detection and miniaturization. Here we report a light-based PCR method, termed as photo-PCR, which enables rapid detection of bacteria in a single step. In th...

In recent years, several protocols based on the extraction of nucleic acids directly from the soil matrix after lysis treatment have been developed for the detection of microorganisms in soil. Extraction efficiency has often been evaluated based on the recovery of a specific gene sequence from an organism inoculated into the soil. The aim of the present investigation was to improve the extracti...

Motivated by biological protocols that require transfer of large pieces of DNA into cells, we here review several aspects of osmotic swelling and lysis of semipermeable unilamellar vesicles. Swelling involves a continuous phase transition from a fluctuating flaccid state to a maximum volume turgid state, without a divergent correlation length and with exponents that violate the hyperscaling rel...

More than 90% of the Plesiomonas shigelloides strains that we tested produced a beta-hemolysin, as judged by the results of agar overlay and contact-dependent hemolysis assays. The hemolysin was cell associated, was active against the erythrocytes of various animal species, and was synthesized at both 25 and 35 degrees C. Activity was lost after thermal or proteolytic treatments or after preinc...