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Moraima Morales-Cruz,1,* Yamixa Delgado,2,* Betzaida Castillo,3 Cindy M Figueroa,4 Anna M Molina,1 Anamaris Torres,2 Melissa Milián,2 Kai Griebenow1,* 1Department of Chemistry, University of Puerto Rico, Río Piedras Campus, San Juan, PR, USA; 2Department of Biochemistry & Pharmacology, San Juan Bautista School of Medicine, Caguas, PR, USA; 3Department of Chemistry, University of Puerto Rico, Humacao Campus, Humacao, PR, USA; 4Department of Math and Sciences, Polytechnic University of Puerto Rico, San Juan, PR, USA*These authors contributed equally to this workCorrespondence: Yamixa Delgado PO Box 4968 Caguas, PR 00726-4968, USATel +1 787 743 3038Fax +1 787 746 3093Email ydelgado@sanjuanbautista.edu Kai Griebenow 17 Ave Universidad STE 1701, San Juan, PR 00925-2537, USATel +1 787 764 0000Fax +1 787 746 3093Email kai.griebenow@upr.eduAbstract: Cancer is the second largest cause of death worldwide with the number of new cancer cases predicted to grow significantly in the next decades. Biotechnology and medicine can and should work hand-in-hand to improve cancer diagnosis and treatment efficacy. However, success has been frequently limited, in particular when treating late-stage solid tumors. There still is the need to develop smart and synergistic therapeutic approaches to achieve the synthesis of strong and effective drugs and delivery systems. Much interest has been paid to the development of smart drug delivery systems (drug-loaded particles) that utilize passive targeting, active targeting, and/or stimulus responsiveness strategies. This review will summarize some main ideas about the effect of each strategy and how the combination of some or all of them has shown to be effective. After a brief introduction of current cancer therapies and their limitations, we describe the biological barriers that nanoparticles need to overcome, followed by presenting different types of drug delivery systems to improve drug accumulation in tumors. Then, we describe cancer cell membrane targets that increase cellular drug uptake through active targeting mechanisms. Stimulus-responsive targeting is also discussed by looking at the intra- and extracellular conditions for specific drug release. We include a significant amount of information summarized in tables and figures on nanoparticle-based therapeutics, PEGylated drugs, different ligands for the design of active-targeted systems, and targeting of different organs. We also discuss some still prevailing fundamental limitations of these approaches, eg, by occlusion of targeting ligands.Keywords: active targeting, drug delivery systems, EPR effect, nanoparticles, passive targeting, stimulus-responsive targeting

Chile, the world's leading copper producer, generates significant volumes of mining waters, some of which cannot be recirculated into the production process. These mining waters are characterized by elevated sulfate ( SO 4 2 − ) concentrations, requiring sustainable management strategies for potential reuse. This study aims to evaluate the rhizofiltration technique using Carpobrotus chilensis for treating mining waters with a high SO 4 2 − concentration. Initially, the mining waters exhibited a pH of 7.97 ± 0.16 and a SO 4 2 − concentration of 2,743 ± 137 mg L−1, while the control water had a pH of 7.88 ± 0.08 and a SO 4 2 − concentration of 775 ± 19.0 mg L−1. The plants were hydroponically cultivated in 40 L containers with mining waters and drinking water as a control. Over an 8-week period, the pH of the mining water decreased to 3.12 ± 0.01, and the SO 4 2 − concentration declined to 2,200 ± 110 mg L−1. Notably, the fresh weight of roots was significantly higher in plants grown in mining water (22.2 ± 6.66 g) compared to those in the control treatment (14.3 ± 4.28 g). However, an undesirable increase in the acidity was observed in the mining waters after rhizofiltration, which was attributed to hydrogen sulfate (HSO4-) and/or root exudates. Despite the unexpected increase in acidity, C. chilensis effectively reduced the concentration of SO 4 2 − in mining waters by 20%. Additionally, the C. chilensis roots accumulated 4.84 ± 1.40% of sulfur (S), a level comparable to thiophore plants. This study provides evidence that this non-aquatic plant can be used in sulfate rhizofiltration. Caprobrotus chilensis is a good candidate for sulfate rhizolfiltration in mining waters. The accumulation of sulfur by the roots of Carpobrotus chilensis reached 4.84% Mining waters with a high concentration of sulfates require control of the redox potential [ABSTRACT FROM AUTHOR]

We report the design, fabrication, and characterization of a porous silicon-based omnidirectional mirror for the near infrared range. The structure consists of 300 porous silicon chirped dielectric layers, optimized to have omnidirectional reflectivity response from 1000 to 2000 nm wavelength range. Measurements of reflectivity spectra are presented for non-polarized light at several incident angles (range 8 ° – 65 °) with a reflectivity > --> 95% covering a 1 μ m band-width. Transfer matrix method calculations were carried out to show the complete angular range for both TM and TE polarizations including a simple model to illustrate the interface scattering effects. [ABSTRACT FROM AUTHOR]

Se ha realizado el estudio histológico del tracto digestivo de Tropidurus peruvianus peruvianus (Lesson). Con las técnicas de coloraciones utilizadas, se obtuvieron los mejores resultados con los métodos de la hematoxilina de Harris-eosina y con lo de Von-Giesson. Se anotan diferencias sistemáticas en comparación con otros vertebrados.