Nanofibers are drawing the attention of engineers and scientists because their large surface-to-volume ratio is favorable for applications in medicine, filter technology, textile industry, lithium-air batteries, and optical sensors. However, when transferring nanofibers to a technical product in the form of a random network of fibers, referred to as nonwoven fabric, the stickiness of the freshly produced and thus fragile nanofiber nonwoven remains a problem. This is mainly because nanofibers strongly adhere to any surface because of van der Waals forces. In nature, there are animals that are actually able to efficiently produce, process, and handle nanofibers, namely cribellate spiders. For that, the spiders use the calamistrum, a comb-like structure of modified setae on the metatarsus of the hindmost (fourth) legs, to which the 10–30 nm thick silk nanofibers do not stick due to a special fingerprint-like surface nanostructure. In this work, we present a theoretical model of the interaction of linear nanofibers with a sinusoidally corrugated surface. This model allows for a prediction of the adhesive interaction and, thus, the design of a suitable surface structure to prevent sticking of an artificially nonwoven of nanofibers. According to the theoretical prediction, a technical analogon of the nanoripples was produced by ultrashort pulse laser processing on different technically relevant metal surfaces in the form of so-called laser-induced periodic surface structures (LIPSS). Subsequently, by means of a newly established peel-off test, the adhesion of an electrospun polyamide fiber-based nonwoven was quantified on such LIPSS-covered aluminium alloy, steel, and titanium alloy samples, as well as on polished (flat) control samples as reference and, additionally, on samples with randomly rough surfaces. The latter revealed that the adhesion of electrospun nanofiber nonwoven is significantly lowered on the nanostructured surfaces compared with the polished surfaces.

This is a well-documented study of the missionary efforts of Protestant denominations among the 100.000 Spanish-speaking Mexicans who became part of the U.S.A. population after the conquest that took from Mexico that vast portion of territory known today as the southwestern United States. It only covers developments during the nineteenth century up to 1900, but it deals with burning missiological questions that are still alive today, not only in that region, such as "the relationship between the nationalist agenda of a powerful nation and the missional goals of a church that reaps the benefits of being a part of that nation" (2).The author is Assistant Dean for the Hispanic Church Studies Department and Associate Professor of Hispanic Studies and Pastoral Leadership at Fuller Theological Seminary in Pasadena, California. His book is missiology at its best because the author's commitment to Christian mission and his familiarity with the Hispanic churches is evident, but at the same time he has made good use of critical historical and sociological approaches to throw light on his complex subject. In the first three chapters, Martinez guides the reader through a wide variety of sources of missionary literature of that period and draws up a sober critical picture of the mixed and confused motivations of mission practitioners and promoters. He deals especially with Presbyterians, Methodists, and Baptists, and an outstanding common note is the intense anti-Catholic bias, which reflects the mood of U.S.A. Protestantism at the time in which a flood of Catholic immigrants from Europe was changing the religious map of the developing nation. For Martinez, "Americanization stood out as the overarching motive among Protestant missionaries for working with Mexican Americans in

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