Single-particle tracking (SPT) is a powerful method for exploring single-molecule dynamics in living cells with nanoscale spatiotemporal resolution. Photostability and bright fluorescence make quantum dots (Qdots) a popular choice for SPT. However, their large size could potentially alter the mobility of the molecule of interest. To test this, we labelled B cell receptors on the surface of B-lymphocytes with monovalent Fab fragments of antibodies that were either linked to Qdots via streptavidin or directly conjugated to the small organic fluorophore Cy3. Imaging of receptor mobility by total internal reflection fluorescence microscopy (TIRFM), followed by quantitative single-molecule diffusion and confinement analysis, definitively showed that Qdots sterically hinder lateral mobility regardless of the substrate to which the cells were adhered. Qdot labelling also drastically altered the frequency with which receptors transitioned between apparent slow- and fast-moving states and reduced the size of apparent confinement zones. Although we show that Qdot-labelled probes can detect large differences in receptor mobility, they fail to resolve subtle differences in lateral diffusion that are readily detectable using Cy3-labelled Fabs. Our findings highlight the utility and limitations of using Qdots for TIRFM and wide-field-based SPT, and have significant implications for interpreting SPT data.

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I. Theme and Structure in the Book of Judges Over the past two and a half decades a number of significant studies have altered the way in which the book of Judges is studied and understood. In 1987, Samuel Dragga drew attention to elements in the book that highlight the failure of Saul. 1 A short while later in this journal, Mark Zvi Brettler advanced the view that a major theme in Judges is the promotion of Judah, often at the expense of Benjamin and the northern tribes. From this, Brettler suggested that much in the book should be read as allegory in which the Davidic dynasty is elevated at the expense of the house of Saul and the northern monarchy. 2 Recently, others have built on the work of these scholars to argue persuasively and at greater length for the presence of anti-Saulide polemic throughout the book. 3

Commentators on Ruth 3.3-4 often pause to note the kethib—qere found in these verses, explaining the unusual form of the kethibs ‭יחדריו‬ and ‭יחבכשו‬ as archaic second feminine singular perfects. This article suggests that the kethib forms found in Ruth 3.3-4 are not archaic, but are the result of an intentional emendation of the text by a scribe intent on reconciling the passage with the teaching of the Torah. The effect of this change is to remove Ruth from any possible intimate encounter with Boaz and replace her with Naomi. Thus, these two readings should be considered as an unrecognized occurrence of tiqqune sopherim.