Using both experimental and theoretical results, this Letter describes how low-energy, feedback control signals can be successfully utilized to suppress (laminarize) chaotic flow in a thermal convection loop.

Пocлeдниe дocтижeния в oблacти тoчнoй oбpaбoтки мaлыч кaнaлoв пoэвoлилн пpимeнять тaкиe микpoкaнaлы в cвepчкoмпaктныч выcoкoэффeктивныч тeплooбмeнникaч, кoгдa oтнoщeииe плoщaди пoвepчнocти кaнaлoв к oбьeмy вeликo, тaк чтo пepeиoc бoльщич тeплoвыч пoтoкoв ocyщecтвляeтcя c мaлыми тeплoвыми coпpoтивлeниями. B чacтиocти, тaкиe микpoкaнaлы мoгyг мoнтиpoвaтьcя нeпocpeдcтвeннo нa oбpaтнoй cтopoнe элeктpoниыч чипoв c цeлью ич oчлaждeния. B нacтoящeм иccлeдoвaнни paccмaтpивaeмыe тeплooбмeниики aнaлиэиpyютcя нa ocнoвe чиcлeннoгo peщeния coпpяжeннoй эaдaчн тeнлoпepeнoca, пoэвoляющeгo oпpeдeлить тeмпepaтypиыe пoля в твepдoй пoдлoжкe н жидкocти. Кpoмe тoгo, пpивoдитcя pacчeтный aлгopнтм для выбopa paэмepoв тeплooбмeнникoв.

A simple, point of care, inexpensive, disposable cassette for the detection of nucleic acids extracted from pathogens was designed, constructed, and tested. The cassette utilizes a single reaction chamber for isothermal amplification of nucleic acids. The chamber is equipped with an integrated, flow-through, Flinders Technology Associates (Whatman FTA®) membrane for the isolation, concentration, and purification of DNA and/or RNA. The nucleic acids captured by the membrane are used directly as templates for amplification without elution, thus simplifying the cassette's flow control. The FTA membrane also serves another critical role—enabling the removal of inhibitors that dramatically reduce detection sensitivity. Thermal control is provided with a thin film heater external to the cassette. The amplification process was monitored in real time with a portable, compact fluorescent reader. The utility of the integrated, single-chamber cassette was demonstrated by detecting the presence of HIV-1 in oral fluids. The HIV RNA was reverse transcribed and subjected to loop-mediated, isothermal amplification (LAMP). A detection limit of less than 10 HIV particles was demonstrated. The cassette is particularly suitable for resource poor regions, where funds and trained personnel are in short supply. The cassette can be readily modified to detect nucleic acids associated with other pathogens borne in saliva, urine, and other body fluids as well as in water and food.