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The life cycle of intracellular pathogens is often complex and can include different morphoforms. Treatment of intracellular infections and unperturbed studying of the pathogen inside the host cell are frequently challenging. Here, we present a Raman-based, label-free, non-invasive, and non-destructive method to localize, visualize, and even quantify intracellular bacteria in 3D within intact host cells in a

In countless speeches and articles in La Follette’s Magazine, Belle Case La Follette urged that women needed the vote to secure “standards of cleanliness and healthfulness in the municipal home,” a...

Most applications of monitoring microalgae necessitate fast deployable and sensitive methods to assess cellular physiology, preferably at the scale of single cells. Vibrational spectroscopies, namely Fourier transform infrared (FT-IR) and Raman spectroscopy, have been proven to be valuable tools since they are label-free, nondestructive, and fast applicable. Infrared spectra contain spectral contributions of macromolecules, such as proteins, nucleic acids, carbohydrates, biosilica and lipids. A major concern of this method is the requirement to dry the sample, which might severely affect cellular physiology. Raman spectroscopy, on the other hand, can be applied in aqueous environments, and provides complementary information to FT-IR spectroscopy, because Raman spectra of microalgae are dominated by the photosynthetic pigments, e.g. chlorophyll a and carotenoids. In our current study we applied both spectroscopy methods to study chemical variations within individual cells of the diatom Ditylum brightwellii during the course of growth phases. Culture growth was monitored via cell counting and related spectral changes were examined employing partial least square (PLS) regression and linear discriminant analysis (LDA) classification. FT-IR models revealed a pronounced decrease of protein and carbohydrate content, a concurrent increase in cellular lipid level and constant biosilica content during culture growth. Interestingly, the highest nucleic acid content appeared in the stationary phase. Raman based models could easily identify cells in the exponential phase indicating highest chlorophyll a amount in that particular stage. Further cell proliferation was accompanied with distinct variances in the carotenoid pool. Comparison of model performances showed that Raman based models were more stable and more accurate than respective FT-IR based models. This leads us to conclude that Raman spectroscopy is a promising method for examining microalgal cell physiology.

Surface layer proteins (S-layer) of Lysinibacillus sphaericus JG-B53 are biological compounds with several bio-based technical applications such as biosorptive materials for heavy and noble metals removal or rare metals recovery from the environment. Despite their well-described applications, a deeper understanding of their metal sorption behavior still remains challenging. The metal sorption stability of gold, palladium, platinum and europium was investigated by ICP-MS, AFM and QCM-D which enables the detection of the sorption in real-time during the in-situ experiments. The results indicate a high binding of Pd, followed by Au, Eu and Pt to the proteins. The comparison between the different methods allowed a deeper understanding of the metal sorption of the isolated S-layer proteins either frees in liquid, adsorbed forming a protein layer or as the bacteria surface.

Le tremblement de terre et l’incendie devastateurs qui frapperent San Francisco en 1906 marquerent une cassure dans l’evolution sociale, politique, et economique de la ville, laissant le champ libre a une competition feroce pour sa reconstruction. L’exploration des tensions qui resulterent des visions conflictuelles de la reconstruction servira a illustrer ici une partie des problemes qui ont souvent caracterise les suites des catastrophes naturelles dans les villes americaines. Aussitot apres le tremblement de terre et l’incendie, 5 610 « earthquake cottages » de deux a trois pieces, construits en bois et transportables, ont ete etablis sur les terrains municipaux pour loger les familles modestes. Malgre leur succes, les cottages ont ete rapidement la cible d’interets economiques et consideres comme des obstacles a surmonter. Les tres faibles risques que ces habitations engendraient pour la sante publique ont ete exageres, de maniere a autoriser leur delocalisation ou leur elimination de plusieurs quartiers habites par les classes populaires. Ces efforts d’extirpation se sont intensifies lorsque le quartier qui accueillait le plus grand nombre de cottages a ete choisi pour devenir le site de la « Panama Pacific International Exposition » de 1915. Le reve des milliers de foyers modestes dissemines dans les quartiers de San Francisco fut ainsi detruit par les interets commerciaux. Cette promesse trahie du logement apres le desastre s’avere un episode tres significatif, quoique peu connu, de l’histoire de San Francisco. L’histoire des « earthquake cottages » illustre comment la corruption et le desir du profit ont porte prejudice a la satisfaction des besoins en logements modestes mais decents. Elle offre cependant quelques lueurs d’espoir puisque la creation de maisons abordables et saines a reussi a s’inscrire, au moins dans un premier temps, dans le debat sur la reconstruction de la ville apres la catastrophe.

La Follette's Autobiography: A Personal Narrative of Political Experiences is a remarkable primary document of the Progressive Era. Originally published in 1913, it remains in print today and has the dubious honor of being one of Richard Nixon's three favorite books. It illuminates the crucial role that La Follette's home state of Wisconsin played in molding La Follette as a man and as a politician, thereby influencing his national progressive agenda; but it also reveals much more.

Environmental Justice incorporates an inclusive definition of its subject matter, exploring the environmental burdens impacting all marginalized populations and communities. This expansive definiti...

The importance of offering a lesbian and gay American history course was initially im pressed upon me in 1986. A newly minted Ph.D., I was teaching my very first class: a U.S. history survey at San Francisco State University (sfsu). The course required each student to review a book of his or her choice on any topic in U.S. history. One student chose John D'Emilio's Sexual Politics, Sexual Communities: The Making of a Homosexual Minority in the United States, 1940?1970 from my list of suggested titles and wrote a thoughtful, enthusiastic review.1 At the bottom of the review was a handwritten note: "Thanks for recommending this book. As a gay man, I didn't know I had a history." Didn't know he had a history?! My fellow historians will share my sense of dismay and my determination to remedy this unthinkable state of affairs. I have always included the history of gay men and lesbians in my various classes, not as a sop to "political correctness" and not because it is an amusing/interesting "add on" to "real" history, but because it is a vital component of a more complete understanding of American political, economic, social, legal, military, and religious history. For example, my courses that focus on the twentieth century include the significant role that the cam paign against homosexuals played in McCarthy-era persecutions; in "U.S. Historical Ge ography" (which examines the role physical geography has played in the development of the United States), we study how and why the coastal cities of New York and San Fran cisco emerged as major centers of homophile populations; in women's history courses we examine the controversy and contributions lesbians brought to various feminist move ments.