Antimicrobial Activity of Copolymer Structures from Bio-Based Monomers.

The urgent need for new antimicrobial compounds has led scientists to explore antimicrobial peptides (AMPs) and antimicrobial polymers as solutions for multidrug resistance. In this study, we synthesized copolymers with cationic and hydrophobic moieties by free-radical polymerization (FRP) using a chain transfer agent to control molecular weights. The potential of natural products as part of the hydrophobic moiety was evaluated, along with variations in their monomer content (13-25%) and the molecular weight (MW) of the copolymer (5000-20,000 g·mol).

Improved Interfacial Electron Dynamics with Block Poly(4-vinylpyridine)-Poly(styrene) Polymers for Efficient and Long-Lasting Dye-Sensitized Solar Cells.

Dye-sensitized solar cells (DSSCs) have recently entered the market for indoor photovoltaics. Fast electron injection from dye to titania, the lifetime of the excited dye, and the suppression of back electron recombination at the photoanode/electrolyte interface are crucial for a high photocurrent conversion efficiency (PCE). This study presents block copolymers of poly(4-vinylpyridine) and poly(styrene)-P4VP--PSt as efficient accelerators of electron injection from dye to titania with extended lifetime excited states and long-lasting back electron recombination suppression.

Self-actualization and B-values: Development and validation of two instruments in the Brazilian context.

Self-actualization is a complex psychological construct within Maslow's motivation theory, characterized by numerous gaps in the empirical and measurement spectrums. Therefore, the objectives of this study are to develop, validate, and cross-verify measures for self-actualization attributes and B-values, focusing on job context and theoretical congruence with innovative behavior and human values related to the self-actualization construct (suprapersonal subfunction). This study involved a diverse sample of 621 Brazilian participants from 25 different professions, indicating the broad applicability of the findings.

An Innovative Approach for Tailoring Molecularly Imprinted Polymers for Biosensors-Application to Cancer Antigen 15-3.

This work presents a novel approach for tailoring molecularly imprinted polymers (MIPs) with a preliminary stage of atom transfer radical polymerization (ATRP), for a more precise definition of the imprinted cavity. A well-defined copolymer of acrylamide and ,'-methylenebisacrylamide (PAAm-co-PMBAm) was synthesized by ATRP and applied to gold electrodes with the template, followed by a crosslinking reaction. The template was removed from the polymer matrix by enzymatic/chemical action.

Recycling Polyethylene/Polyamide Multilayer Films with Poly(isoprene--Maleic Anhydride) Compatibilizer.

Polymers generally form incompatible mixtures that make the process of recycling difficult, especially the mechanical recycling of mixed plastic waste. One of the most commonly used films in the packaging industry is multilayer films, mainly composed of polyethylene (PE) and polyamide (PA). Recycling these materials with such different molecular structures requires the use of compatibilizers to minimize phase separation and obtain more useful recycled materials.

Electrochemically Mediated Atom Transfer Radical Polymerization Driven by Alternating Current.

Alternating current (AC) and pulsed electrolysis are gaining traction in electro(organic) synthesis due to their advantageous characteristics. We employed AC electrolysis in electrochemically mediated Atom Transfer Radical Polymerization (eATRP) to facilitate the regeneration of the activator Cu complex on Cu electrodes. Additionally, Cu served as a slow supplemental activator and reducing agent (SARA ATRP), enabling the activation of alkyl halides and the regeneration of the Cu activator through a comproportionation reaction.

Psychometric properties of the Brazilian-Portuguese Flow State Scale Short (FSS-BR-S).

"Flow experience" is a term used to describe the state of being fully immersed in what you are doing. The Flow State Scale (FSS-2) was developed to assess how people feel when they are in the flow state while participating in certain sports activities. The goal of this study was to obtain a short adapted version of the FSS-2 for the Brazilian-Portuguese language and for general activities (FSS-BR-S).

Replacing Harmful Flame Retardants with Biodegradable Starch-Based Materials in Polyethylene Formulations.

The addition of toxic flame retardants to commercially available polymers is often required for safety reasons due to the high flammability of these materials. In this work, the preparation and incorporation of efficient biodegradable starch-based flame retardants into a low-density polyethylene (LDPE) matrix was investigated. Thermoplastic starch was first obtained by plasticizing starch with glycerol/water or glycerol/water/choline phytate to obtain TPS-G and TPS-G-CPA, respectively.

Fast-Gelling Polyethylene Glycol/Polyethyleneimine Hydrogels Degradable by Visible-Light.

The treatment of burn wounds remains a clinical challenge due to the need for repeated dressings changes. Therefore, the development of a dressing system that can be atraumatically removed from the wound bed can be considered a breakthrough and improve treatment times. In this work, the development of an injectable, fast-gelling hydrogel is proposed that can change its mechanical properties when exposed to visible light.

Autism spectrum disorders: students' view of medicine and nursing courses at a public university.

The term stigma comes from Greek, being related to the identification of people through a physical mark, which can generate marginalization. The literature points out four types of stigmas: public, institutional, self-esteem, and courtesy. People with Autistic Spectrum Disorders are stigmatized in various cultures and societies.

Evaluation of Biphasic Calcium Phosphate Scaffolds Derived from Cuttlefish Bone Coated with Poly(ester urea) for Bone Tissue Regeneration.

This study investigates the osteogenic differentiation of umbilical-cord-derived human mesenchymal stromal cells (hUC-MSCs) on biphasic calcium phosphate (BCP) scaffolds derived from cuttlefish bone doped with metal ions and coated with polymers. First, the cytocompatibility of the undoped and ion-doped (Sr, Mg and/or Zn) BCP scaffolds was evaluated for 72 h using Live/Dead staining and viability assays. From these tests, the most promising composition was found to be the BCP scaffold doped with strontium (Sr), magnesium (Mg) and zinc (Zn) (BCP-6Sr2Mg2Zn).

Facile Synthesis of Highly Stretchable, Tough, and Photodegradable Hydrogels.

Recently, highly stretchable and tough hydrogels that are photodegradable on-demand have been reported. Unfortunately, the preparation procedure is complex due to the hydrophobic nature of the photocrosslinkers. Herein, a simple method is reported to prepare photodegradable double-network (DN) hydrogels that exhibit high stretchability, toughness, and biocompatibility.

Targeted downregulation of MYC mediated by a highly efficient lactobionic acid-based glycoplex to enhance chemosensitivity in human hepatocellular carcinoma cells.

The chemosensitization of tumor cells by gene therapy represents a promising strategy for hepatocellular carcinoma (HCC) treatment. In this regard, HCC-specific and highly efficient gene delivery nanocarriers are urgently needed. For this purpose, novel lactobionic acid-based gene delivery nanosystems were developed to downregulate c-MYC expression and sensitize tumor cells to low concentration of sorafenib (SF).

pH-responsive nanoparticles based on POEOMA-b-PDPA block copolymers for RNA encapsulation, protection and cell delivery.

The use of gene-based products, such as DNA or RNA, is increasingly being explored for various innovative therapies. However, the success of these strategies is highly dependent on the effective delivery of these biomolecules to target cells. Therefore, the development of pH-responsive nanoparticles comprises the creation of intelligent delivery systems with high therapeutic efficiency.

IoT Clusters for Enhancing Multimedia Applications.

In this paper, we present a framework for exploring the spare capacity of IoT devices for clustered execution of multimedia applications. Applications of this type are usually framed with specific quality parameters that enable a desirable level of service. This means that the IoT cluster must guarantee strict quality ranges of service to work as expected.

Checklist validation for use in safe heart surgery.

Objective: Build and validate an instrument in checklist format for use in safe cardiac surgery.

Method: Methodological research carried out in the following stages: literature review; national construction of items and content validation by experts in two stages, at regional level 9 and with 41 judges. For data analysis, the agreement rate per constructed item was determined.

Scaling-Up an Aqueous Self-Degassing Electrochemically Mediated ATRP in Dispersion for the Preparation of Cellulose-Polymer Composites and Films.

Electrochemically mediated atom transfer radical polymerization (ATRP) is developed in dispersion conditions to assist the preparation of cellulose-based films. Self-degassing conditions are achieved by the addition of sodium pyruvate (SP) as a ROS scavenger, while an aluminum counter electrode provides a simplified and more cost-effective electrochemical setup. Different polyacrylamides were grown on a model cellulose substrate which was previously esterified with 2-bromoisobutyrate (-BriB), serving as initiator groups.

Engineering silica-polymer hybrid nanosystems for dual drug and gene delivery.

In recent years, it has been shown that a combination of different antitumour strategies involving distinct therapeutic agents, such as chemical compounds and genetic material, could result in an effective therapeutic activity that is much higher than that obtained by conventionally used individual approaches. Therefore, the main goal of this work was to develop a new hybrid nanosystem based on mesoporous silica nanoparticles and polymers to efficiently transport and deliver drug and plasmid DNA into cancer cells. Moreover, its potential to mediate a combinatorial antitumour strategy involving epirubicin and herpes simplex virus thymidine kinase/ganciclovir (HSV-TK/GCV) gene therapy was evaluated.

Photo-degradable, tough and highly stretchable hydrogels.

We present for the first time highly stretchable and tough hydrogels with controlled light-triggered photodegradation. A double-network of alginate/polyacrylamide (PAAm) is formed by using covalently and ionically crosslinked subnetworks. The ionic Ca alginate interpenetrates a PAAm network covalently crosslinked by a bifunctional acrylic crosslinker containing the photodegradable -nitrobenzyl (ONB) core instead of the commonly used methylene bisacrylamide (MBAA).

Dual electrochemical and chemical control in atom transfer radical polymerization with copper electrodes.

In Atom Transfer Radical Polymerization (ATRP), Cu acts as a supplemental activator and reducing agent (SARA ATRP) by activating alkyl halides and (re)generating the Cu activator through a comproportionation reaction, respectively. Cu is also an unexplored, exciting metal that can act as a cathode in electrochemically mediated ATRP (ATRP). Contrary to conventional inert electrodes, a Cu cathode can trigger a dual catalyst regeneration, simultaneously driven by electrochemistry and comproportionation, if a free ligand is present in solution.

Application of vinyl polymer-based materials as nucleic acids carriers in cancer therapy.

Nucleic acid-based therapies have changed the paradigm of cancer treatment, where conventional treatment modalities still have several limitations in terms of efficacy and severe side effects. However, these biomolecules have a short half-life in vivo, requiring multiple administrations, resulting in severe suffering, discomfort, and poor patient compliance. In the early days of (nano)biotechnology, these problems caused concern in the medical community, but recently it has been recognized that these challenges can be overcome by developing innovative formulations.