On a very small surface, a chip, several thousands of oligonucleotides, can be synthesized using a mask technology. Given a set of oligos, the problems tackled here are: What is the minimum number of masks necessary to synthesize one copy of each oligo? How long will be the series of masks if each oligo is synthesized twice, such that the two copies are realized with two completely different se...

In case of a new influenza pandemic, provision of masks to coughing patients could be used to slow expansion of the epidemic. To quantitatively assess the efficacy of different masks, we used an ultrasonic anemometer to measure the velocity of airflow from the mouth in coughing. We found that even the cheapest paper masks reduced the air speed to less than 1/10, implicating their effectiveness ...

BACKGROUND A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding ho...

Polarization from photomasks can be used as a new lever to improve lithographic performance in both binary and phase-shifting masks (PSMs). While PSMs manipulate the phase of light to control the temporal addition of electric field vectors, polarization masks manipulate the vector direction of electric field vectors to control the spatial addition of electric field components. This paper explor...

We propose a number of pre-distorted mask design techniques for binary and phase-shifting masks. Our approach is based on modeling the imaging mechanism of a stepper by the Hopkins equations and taking advantage of the contrastenhancement characteristics of photoresist. Optimization techniques such as the branch and bound algorithm and simulated annealing algorithm are used to systematically de...