Using Hybrid Coating to Fabricate Highly Stable and Expandable Transparent Liquid Marbles.

Liquid marbles (LMs) are microliter-scale droplets coated with hydrophobic solid particles. The particle size and hydrophobicity of the surface coating determine their properties, such as transparency, expandability, and resistance to evaporation and coalescence, one or more of which can be critical to their application as microreactors. This study reports the use of a mixture of two different hydrophobic powders for fabrication of LMs for colorimetric assays: trichloro(1,1,2,2-perfluorooctyl) silane-linked silica gel (modified silica gel (MSG), particle size: 40-75 μm) and hexamethyldisilazane-linked fumed silica (modified fumed silica (MFS), average aggregate length: 200-300 nm).

Cellulose acetate microwell plates for high-throughput colorimetric assays.

Single use plasticware (SUP) in scientific, diagnostic, and academic laboratories makes a significant contribution to plastic waste generation worldwide. Polystyrene (PS) microwell plates form a part of this waste. These plates are the backbone of high throughput colorimetric measurements in academic, research, and healthcare settings for detection/quantification of wide-ranging analytes including proteins, carbohydrates, nucleic acids, and enzyme activity.

RING Program: The CFAR Diversity, Equity, and Inclusion Pathway Initiative.

Background: Case Western Reserve University (CWRU)/University Hospitals Cleveland Medical Center in Cleveland, OH, and the University of Pittsburgh (Pitt) in Pittsburgh, PA, forged a strategic alliance to form the Rustbelt Center for AIDS Research. The Rustbelt Center for AIDS Research developed a National Institutes of Health-supported diversity, equity, and inclusion pathway initiative termed the "Rustbelt Investigators for the Next Generation (RING) Program" that provides research training experiences for Puerto Rican students that will help them pursue a biomedical research career in HIV.

Setting: The RING Program provides 10-week research training experiences in different disciplines of HIV/AIDS for under-represented minority undergraduate and masters students from 4 campuses (Río Piedras, Mayagüez, Humacao, and Cayey) at the University of Puerto Rico.

Disaster solidarity and survivor ethics: a case study of Hurricane María in Puerto Rico.

Liminal periods of disaster solidarity in the aftermath of disaster are a common experience of many survivors. These periods have a specifically ethical component in that people spontaneously engage in collective, altruistic action and magnanimously expand their ethical focus beyond normative social distinctions and hierarchies. Inevitably, however, such solidarity seems to wane, and people return to pre-disaster patterns of interaction.

From Undergraduate Research to Graduation: Measuring the Robustness of the Pathway at a Hispanic-Serving Institution.

Based on several regression specifications that control for a host of covariates, this article demonstrates that the quantity of undergraduate research experience was by far the most important determinant for increased graduation rates at a 100% Hispanic-serving institution. Our finding also shows a causal relationship confirmed by propensity score matching analyses. Results underscore the high impact but sometimes underestimated contribution of undergraduate research to academic success, even for teaching-oriented colleges.

Models of Classroom Assessment for Course-Based Research Experiences.

Course-based research pedagogy involves positioning students as contributors to authentic research projects as part of an engaging educational experience that promotes their learning and persistence in science. To develop a model for assessing and grading students engaged in this type of learning experience, the assessment aims and practices of a community of experienced course-based research instructors were collected and analyzed. This approach defines four aims of course-based research assessment - 1) Assessing Laboratory Work and Scientific Thinking; 2) Evaluating Mastery of Concepts, Quantitative Thinking and Skills; 3) Appraising Forms of Scientific Communication; and 4) Metacognition of Learning - along with a set of practices for each aim.

Student Attitudes Contribute to the Effectiveness of a Genomics CURE.

The Genomics Education Partnership (GEP) engages students in a course-based undergraduate research experience (CURE). To better understand the student attributes that support success in this CURE, we asked students about their attitudes using previously published scales that measure epistemic beliefs about work and science, interest in science, and grit. We found, in general, that the attitudes students bring with them into the classroom contribute to two outcome measures, namely, learning as assessed by a pre- and postquiz and perceived self-reported benefits.

Knowledge and Attitudes about Transgender Healthcare: Exploring the Perspectives of Hispanic Medical Students.

Objective: The aim of this study was to explore the knowledge and attitudes about transgender care in Hispanic medical students at the University of Puerto Rico School of Medicine (UPR SOM).

Methods: Medical students at the UPR SOM were invited to participate in a questionnaire to assess their attitudes and knowledge about the healthcare of transgender patients. The data were analyzed as percentages and averages using Stata version 14.

Dual Singlet Excited-State Quenching Mechanisms in an Artificial Caroteno-Phthalocyanine Light Harvesting Antenna.

Under excess illumination, photosystem II of plants dissipates excess energy through the quenching of chlorophyll fluorescence in the light harvesting antenna. Various models involving chlorophyll quenching by carotenoids have been proposed, including (i) direct energy transfer from chlorophyll to the low-lying optically forbidden carotenoid S state, (ii) formation of a collective quenched chlorophyll-carotenoid S excitonic state, (iii) chlorophyll-carotenoid charge separation and recombination, and (iv) chlorophyll-chlorophyll charge separation and recombination. In previous work, the first three processes were mimicked in model systems: in a Zn-phthalocyanine-carotenoid dyad with an amide linker, direct energy transfer was observed by femtosecond transient absorption spectroscopy, whereas in a Zn-phthalocyanine-carotenoid dyad with an amine linker excitonic quenching was demonstrated.

Atomic Structures of Single-Layer Nanoislands of Ni, Cu, Rh, Pd, Ag, Ir, Pt, Au Supported on Au(111) from Density Functional Theory Calculations.

We have used density functional theory calculations to study the atomic structure of single-layer nanoislands of metal M (M=Ni, Cu, Rh, Pd, Ag, Ir, Pt, Au) supported on M(111) and Au(111) surfaces. Nanoislands of Cu, Pd, Ag, Pt, and Au have planar structures on Au(111), while nanoislands of Ni, Rh, and Ir are nonplanar. The calculations also show that nanoislands of Cu, Pd, Pt, and Au on Au(111) with a diameter below 3 nm can have one of several atomic structures.

Hydrogen Adsorption on Au-Supported Pt and Pd Nanoislands: A Computational Study of Hydrogen Coverage Effects.

We have studied the dissociative adsorption of hydrogen under high coverage conditions of adsorbed hydrogen on Pd and Pt nanoislands supported on Au(111) using Density Functional Theory calculations. The results reveal that for Pd/Au(111), the free energy of hydrogen adsorption Δ is close to 0 kJ/mol when the coverage of adsorbed hydrogen is near 1 ML, where the available catalytic sites are located at the edges of the Pd nanoislands. In the case of Pt/Au(111), Δ ≈ 0 kJ/mol under a broad range of hydrogen coverage conditions, from 1 ML to 3 ML, depending on the size of the Pt nanoislands.

Simulation of Metal-Supported Metal-Nanoislands: A Comparison of DFT Methods.

We have evaluated various density functional theory (DFT) methods to simulate geometric, energetic, electronic, and hydrogen adsorption properties of metal-nanoparticles supported on metal surfaces. We used Pt and Pd nanoislands on Au(111) as model systems. The evaluated DFT methods include GGA (PW91, PBE, RPBE, revPBE, and PBESol), GGA with van der Waals (vdW) corrected (PBE-D3), GGA with optimized vdW functionals (revPBE-vdW), meta-GGA (SCAN and MS2), and the machine learning-based method BEEF-vdW.

Colorism and Health Disparities in Home Countries: The Case of Puerto Rico.

This study reveals the association of skin color with health disparities in Puerto Rico, a US territory that is home to the second largest Latino population in the US. Aware of the inadequacy of standard OMB ethno-racial categories in capturing racial differences among Latinos, we incorporated skin color scales into the Puerto Rico BRFSS. We apply both logistic regressions and propensity score matching techniques.

DFT Calculations of the Adsorption States of O on OH/HO-Covered Pt(111).

The adsorption of O on Pt(111) was studied with Density Functional Theory calculations. Various adsorbed states of O were evaluated on clean and OH/HO-covered Pt(111) surfaces at the solid/gas and solid/liquid interfaces. The results reveal that the adsorption of O on OH/HO-covered Pt(111) surface starts with the physical adsorption of O.

Strain and Low-Coordination Effects on Monolayer Nanoislands of Pd and Pt on Au(111): A Comparative Analysis Based on Density Functional Results.

Recent experiments demonstrated that the catalytic centers for the hydrogen evolution reaction (HER) are different on Pd and Pt nanoislands on Au(111). Inspired by these experiments, we examined the geometric, energetic, electronic and hydrogen adsorption properties of monolayer model nanoislands of Pd and Pt supported on Au(111) with density functional theory calculations. Accordingly, Au-tensile strain effects can be nearly 50% larger on the geometric structure of nanoislands of Pd on Au(111) than their Pt analogs, resulting on different electronic properties for these nanoislands.

HYSCORE and DFT Studies of Proton-Coupled Electron Transfer in a Bioinspired Artificial Photosynthetic Reaction Center.

The photosynthetic water-oxidation reaction is catalyzed by the oxygen-evolving complex in photosystem II (PSII) that comprises the MnCaO cluster, with participation of the redox-active tyrosine residue (Y) and a hydrogen-bonded network of amino acids and water molecules. It has been proposed that the strong hydrogen bond between Y and D1-His190 likely renders Y kinetically and thermodynamically competent leading to highly efficient water oxidation. However, a detailed understanding of the proton-coupled electron transfer (PCET) at Y remains elusive owing to the transient nature of its intermediate states involving Y⋅.

Immobilization of Phosphatidylinositides Revealed by Bilayer Leaflet Decoupling.

Phosphatidylinositol 4,5-bisphosphate (PIP) has a significantly lower mobile fraction than most other lipids in supported lipid bilayers (SLBs). Moreover, the fraction of mobile PIP continuously decreases with time. To explore this, a bilayer unzipping technique was designed to uncouple the two leaflets of the SLB.

Possible Role for Toll-Like Receptors in Interaction of Fasciola hepatica Excretory-Secretory Products with Human Monocyte Cell Line.

This chapter presents a proteomic approach to purify and identify native excretory-secretory products (ESPs) in the range of >10-30 kDa proteins capable of interacting with toll-like receptors (TLRs). Here we present a protocol to fractionate the total ESPs using an ultrafiltration system to recover ESP proteins >10-30 kDa. The fraction of the proteins >10-30 kDa is purified by ion exchange chromatography (IEC) using a mono Q-column in a fast protein liquid chromatography system (FPLC) to separate its components based on charge.

Purification of Native Fasciola hepatica Fatty Acid-Binding Protein and Induction of Alternative Activation of Human Macrophages.

This chapter presents the different techniques to purify the native forms of Fasciola hepatica fatty acid-binding protein (Fh12) using size exclusion chromatography and isoelectric focusing (IEF). Also, it presents the procedure to study the immunological effect of the purified protein Fh12 using monocyte-derived macrophages (MDM) obtained from healthy human donors. For this purpose, I present the procedure to isolate and culture peripheral blood mononuclear cells (PBMCs) to generate alternatively activated macrophages (AAMΦ) by in vitro exposure to Fh12.

Facilitating Growth through Frustration: Using Genomics Research in a Course-Based Undergraduate Research Experience.

A hallmark of the research experience is encountering difficulty and working through those challenges to achieve success. This ability is essential to being a successful scientist, but replicating such challenges in a teaching setting can be difficult. The Genomics Education Partnership (GEP) is a consortium of faculty who engage their students in a genomics Course-Based Undergraduate Research Experience (CURE).

Linear correlation models for the redox potential of organic molecules in aqueous solutions.

In this study, we use the molecular orbital energy approximation (MOEA) and the energy difference approximation (EDA) to build linear correlation models for the redox potentials of 53 organic compounds in aqueous solutions. The molecules evaluated include nitroxides, phenols, and amines. Both the MOEA and EDA methods yield similar correlation models, however, the MOEA method is less computationally expensive.

Simalikalactone D, a Potential Anticancer Compound from , an Endemic Plant of Puerto Rico.

Species of the genus have been studied because of their antimalarial and antileukemic activities. A group of oxygenated terpenes called quassinoids have been isolated from species of the genus, and are responsible for its therapeutic properties. We hypothesized that , an endemic plant from Puerto Rico, is a natural source rich in quassinoid compounds with anticancer activity.