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The COVID-19 pandemic has brought to light the need for fast and sensitive detection methods to prevent the spread of pathogens. The scientific community is making a great effort to design new molecular detection methods suitable for fast point-of-care applications. In this regard, a variety of approaches have been developed or optimized, including isothermal amplification of viral nucleic acids, CRISPR-mediated target recognition, and read-out systems based on nanomaterials. Herein, we present CASCADE (CRISPR/CAS-based Colorimetric nucleic Acid DEtection), a sensing system for fast and specific naked-eye detection of SARS-CoV-2 RNA. In this approach, viral RNA is recognized by the LwaCas13a CRISPR protein, which activates its collateral RNase activity. Upon target recognition, Cas13a cleaves ssRNA oligonucleotides conjugated to gold nanoparticles (AuNPs), thus inducing their colloidal aggregation, which can be easily visualized. After an exhaustive optimization of functionalized AuNPs, CASCADE can detect picomolar concentrations of SARS-CoV-2 RNA. This sensitivity is further increased to low femtomolar (3 fM) and even attomolar (40 aM) ranges when CASCADE is coupled to RPA or NASBA isothermal nucleic acid amplification, respectively. We finally demonstrate that CASCADE succeeds in detecting SARS-CoV-2 in clinical samples from nasopharyngeal swabs. In conclusion, CASCADE is a fast and versatile RNA biosensor that can be coupled to different isothermal nucleic acid amplification methods for naked-eye diagnosis of infectious diseases. ; This work was supported by the Spanish Ministry of Economy and Competitiveness (SAF2017-87305-R, PID2020-119352RB-I00), Instituto de Salud Carlos III (FONDO-COVID19:COV20/00144 and COV20/00122) and Madrid Regional Government (NANOCOV-CM and IND2017/IND7809). C.E-N, M. L-V and C.R-D thank Madrid Regional Government for the pre-doctoral Grants (PEJD-2017-PRE/BMD-3730, PEJD-2018-PRE/IND-9584 and PEJD-2017-PRE/IND-4438). P.M.R thanks the Ministry of Economy, Industry and ...

The irradiation of gold nanorod colloids with a femtosecond laser can be tuned to induce controlled nanorod reshaping, yielding colloids with exceptionally narrow localized surface plasmon resonance bands. The process relies on a regime characterized by a gentle multishot reduction of the aspect ratio, whereas the rod shape and volume are barely affected. Successful reshaping can only occur within a narrow window of the heat dissipation rate: Low cooling rates lead to drastic morphological changes, and fast cooling has nearly no effect. Hence, a delicate balance must be achieved between irradiation fluence and surface density of the surfactant on the nanorods. This perfection process is appealing because it provides a simple, fast, reproducible, and scalable route toward gold nanorods with an optical response of exceptional quality, near the theoretical limit. ; This work was funded by the Spanish MINECO (Ministry of Economy and Competitiveness; grants CTQ2012-37404-C02-01, MAT2013-46101-R, MAT2014-59678-R, ENE2015-70300-C3-3-R, and CTQ2015-65033-P), the EUROfusion Consortium (AWP15-ENR-01/CEA-02), the Madrid Regional Government (S2013/MIT-2775 and S2013/MIT-2807), and the European Research Council (ERC Advanced Grant 267867, Plasmaquo). A.G.-M. and G.G.-R. respectively acknowledge receipt of Ramón y Cajal and FPI (Formación de Personal Investigador) fellowships from the Spanish MINECO. P.D.-N. acknowledges receipt of a fellowship from the Madrid Regional Government. The authors acknowledge the computer resources and technical assistance provided by CESVIMA (Centro de Supercomputación y Visualización de Madrid, Universidad Politécnica de Madrid) and the facilities provided by the Center for Ultrafast Lasers and the National Center of Microscopy (Universidad Complutense de Madrid). All results are reported in the main paper and supplementary materials.

This book examines the environmental and technological complexity of South Carolina inland rice plantations from their inception at the turn of the seventeenth century to the brink of their institutional collapse at the eve of the Civil War. Inland rice cultivation provided a foundation for the South Carolina colonial plantation complex and enabled planters' participation in the Atlantic economy, dependence on enslaved labor, and dramatic alteration of the natural landscape. Moreover, the growing population of enslaved Africans led to a diversely-acculturated landscape unique to the Southeastern Coastal Plain. Despite this significance, Lowcountry inland rice cultivation has had an elusive history. Unlike many historical interpretations that categorize inland rice cultivation in a universal and simplistic manner, this study explains how agricultural systems varied among plantations. By focusing on planters' and slaves' alteration of the inland topography, this book emphasizes how agricultural methods met the demands of the local environment.

Cover -- Title Page -- Copyright Page -- Dedication -- Table of Contents -- List of Illustrations -- Acknowledgments -- Introduction: Critical Theory and the Reconstruction of Early Modern Performance -- 1. Revisiting Comedia Reconstruction in a Revisionist Performance Environment -- 2. The Habitus of Corral Scenic Space -- 3. (Re)Placing the Corral Body: Problematizing Semiotics and Gesture -- 4. Staging the Object -- 5. Women/Objects on the Modern and Early Modern Stage: Two Exceptional Case Studies -- 6. Adaptation, Translation, and the Relevance of Classical Theatrical Performance