Garments treated with chemical insecticides are commonly used to prevent mosquito bites. Resistance to insecticides, however, is threatening the efficacy of this technology, and people are increasingly concerned about the potential health impacts of wearing insecticide-treated clothing. Here, we report a mathematical model for fabric barriers that resist bites from Aedes aegypti mosquitoes based on textile physical structure and no insecticides. The model was derived from mosquito morphometrics and analysis of mosquito biting behavior. Woven filter fabrics, precision polypropylene plates, and knitted fabrics were used for model validation. Then, based on the model predictions, prototype knitted textiles and garments were developed that prevented mosquito biting, and comfort testing showed the garments to possess superior thermophysiological properties. Our fabrics provided a three-times greater bite resistance than the insecticide-treated cloth. Our predictive model can be used to develop additional textiles in the future for garments that are highly bite resistant to mosquitoes.

Forming nanocone structures on a silicon (Si) surface by low (<100 eV) energy helium plasma has been proposed in recent years as a simple method for fabricating black Si, which is an attractive material for photon absorption through the solar spectrum. In this study, different appearances of the Si surface were observed and analyzed with a scanning electron microscope. By introducing impurities of molybdenum and tungsten during plasma irradiation, it was revealed that the formation and the distribution of nanocones have a clear dependence on the amount of impurities on the surface.

Sionex Differential Mobility Spectrometer (DMS) sensors can be used as standalone detectors in many applications because of their outstanding sensitivity and selectivity. However, in applications like field screening for toxic chemicals and explosives, the number of possible interferents may be so high that additional separation becomes useful for identification and for quantitative measurement. For these cases, we have developed several different hybrid technologies. (1) DMS-IMS 2 integrates bipolar differential mobility ion filtration with IMS drift time measurement in IMS drift tubes, one tube for each ion polarity. (2)The Sionex GC-DMS (microAnalyzer) combines a pre-concentrator, a rapid and selective GC column that operates at high temperature in an air recirculation loop, and DMS ion filtration and detection.(3) Sionex DMS-MS interfaces have been developed for several types of mass spectrometers, and dramatically improve mass spec performance by filtering out unwanted species to reduce chemical noise and improve measurement accuracy.The Sionex DMS-IMS 2 first uses DMS to select positive and negative ions based on ion mobility variation with field (the α(E) function), then uses paired IMS sections to measure the low field mobility (K(0)). DMS separation depends on many properties including the distribution of internal charges, rigidity, and clustering. The IMS drift times depend on molecular size and conformation at low fields. A number of applications of this technology will be described, including CWA's, TIC/TIM, and explosives.The Sionex microAnalyzer GC-DMS system combines sophisticated preconcentration, thermal desorption, GC temperature ramping, and DMS separation and detection in a compact, portable and field-deployable package. The list of applications for this technology is growing rapidly, currently including CWAs, BTEX, H 2 S and mercaptans, and others.Sionex DMS-MS interfaces are being used to make quantitative measurements of biomarkers, including breath markers, biofluid markers, and cancer-linked agents. DMS-MS improves the performance / cost tradeoff for the mass spectrometer, greatly speeds analysis compared to LC-MS, and maintains measurement accuracy. Differential mobility spectrometry 1,2,3 (DMS) is recognized as a powerful tool for separation and characterization of gasphase ions. In DMS, ions are distinguished by the difference between mobilities at high and low electric fields, exploiting the fact that ion mobility values depend on the applied field strength. Developed and refined over the past decade, differential mobility spectrometry (DMS) is also known as field-asymmetric waveform ion mobility spectrometry (FAIMS) 4 (FAIMS is often used to refer to a coaxial configuration). Several configurations of DMS analyzers have shown response to trace amounts of chemical species including explosives 5,6 , chemical warfare agents and simulants 7 , volatile organic compounds 8 , and a variety of other organic and inorganic substances 9 . Hybrid DMS techniques such as GC-DMS 10 , DMS-IMS 11 , D...

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