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Polymers that are low-cost, lightweight, durable, and eco-friendly can be considered as one of the aims of recent research studies to solve environmental problems, especially those caused by the abundance of plastic wastes. The notable mechanical properties of such polymers could be achieved with reinforcements such as using natural fibers like hemp, sisal, wood-fiber, jute, and the focus of the study, rice husk. Using high-density polyethylene (HDPE) as the matrix, the addition of rice husk fillers was able to improve the mechanical properties of the polymer composites. However, the microstructure of the composite seems to be uneven, and voids could be observed. This must be due to disturbances or inhomogeneity in the interfacial dispersion of the filler (rice husk) and the matrix (polyethylene). This paper aims to introduce a poly (ethylene glycol) methacrylate (PEGMA) compatibilizer that can help provide stronger interfacial dispersion between the filler and matrix to improve the mechanical properties and morphology of the composite. It also offers a broader perspective regarding the possible component combinations and ratios in fabricating polyethylene which may, later on, lead to the manufacture of more efficient polyethylene-based products.

The relationship between suicidality, depression, anxiety, and well-being was explored in young adults (median age 20.7 years) from the State of Yucatan (Mexico), which has a suicide rate double that of other Mexican states. A cross-sectional study was carried out in 20 universities in Yucatan and 9,366 students were surveyed using validated questionnaires built into a smartphone app, applying partial least squares structural equation models. High suicide risk was assessed in 10.8% of the sample. Clinically relevant depression and anxiety levels were found in 6.6% and 10.5% of the sample, respectively, and 67.8% reported high well-being. Comparably higher levels of suicide risk, depression and anxiety, and lower well-being were found in women, who were also somewhat older than men in our study. Furthermore, path analysis in the structural equation model revealed that depression was the main predictor of suicidal behaviour as well as of higher anxiety levels and lower self-perceived well-being in the total sample and in both genders. Our findings draw attention to the association between suicidality, depression, anxiety, and well-being in Yucatan young adults and gender differences with this regard. Mental health screening via smartphone might be a useful tool to reach large populations and contribute to mental health policies, including regional suicide prevention efforts, Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. No funding was received for this study

The ability to detect and characterize drug binding to a target protein is of high priority in drug discovery research. However, there are inherent challenges when the target of interest is an integral membrane protein (IMP). Assuming successful purification of the IMP, traditional approaches for measuring binding such as surface plasmon resonance (SPR) and fluorescence resonance energy transfer (FRET) have been proven valuable. However, the mass dependence of SPR signals may preclude the detection of binding events when the ligand has a significantly smaller mass than the target protein. In FRET-based experiments, protein labeling through modification may inadvertently alter protein dynamics. Graphene Bio-Electronic Sensing Technology (GBEST) aims to overcome these challenges. Label-free characterization takes place in a microfluidic chamber wherein a fluid lipid membrane is reconstituted directly above the GBEST sensor surface. By leveraging the high conductivity, sensitivity, and electrical properties of monolayer graphene, minute changes in electrostatic charges arising from the binding and unbinding of a ligand to a native IMP target can be detected in real time and in a mass-independent manner. Using crude membrane fractions prepared from cells overexpressing monocarboxylate transporter 1 (MCT1), we demonstrate the ability to (1) form a fluid lipid bilayer enriched with MCT1 directly on top of the GBEST sensor and (2) obtain kinetic binding data for an anti-MCT1 antibody. Further development of this novel technology will enable characterization of target engagement by both low- and high-molecular-weight drug candidates to native IMP targets in a physiologically relevant membrane environment.

Based on the recent scientific literature on the social ecology of smartphone addiction, we have examined the empirical relationship between social digital pressure (SDP) and smartphone addiction by also looking at the influence of users’ personalities, psychological distress, social support, and residential social living conditions on this addiction. The analyses were carried out on a nationally representative sample of 2,820 Spanish smartphone users. The results of the causal and multigroup models (structural equation model) indicated that the SDP was positively related to smartphone addiction. This influence was also independent of the effects on smartphone addiction of some personality traits (mainly low conscientiousness), high depression, low social support, and high social disorder in the neighborhood. SDP also showed an important mediating effect mainly for social factors (social support and social disorder in the neighborhood). SDP may be a relevant variable for understanding the potential risk of smartphone addiction in cases where there is a high need for social connection.

The inhibition of porcine pancreatic lipase by the drug orlistat was studied through a series of activities that combine experimental and computational procedures. The enzymatic activity of the lipase was determined by measuring enzyme kinetics and calculating parameters such as Km and Vmax from experimental data. Assays of lipase inhibition by orlistat were used to construct Linewaver–Burk and Dixon plots. Docking calculations are highly recommended to visualize the enzyme–ligand interactions and as an approach to decipher the inhibitor mechanism of action. Furthermore, sequence analysis was included to compare enzyme structures across different organisms, specifically between human and pig as closely related study models, and complement the docking simulations. The educational project proposed here for biochemistry or pharmacy students can enhance the understanding of concepts regarding enzyme kinetics, binding sites, and enzyme–ligand interactions through visualizations.

Purpose Bacterial and fungal communities represent key bioindicators of soil quality and are essential for the maintenance of nutrient availability. Our purpose was to characterize the bacterial and fungal biodiversity associated with different compost mixtures, comparing microbiological indicators regarding the soil quality. Methods Compost samples and mixtures were prepared (15:1 final ratio) with chemical fertilizer, animal manures (bovine, swine, and poultry) and green waste (such as tomato waste and leaves). Bacterial and fungal isolation and identification were performed through standard phenotypic methods. Statistical methods to assess differences between treatments included Shannon diversity, Chi-square tests, Bray-Curtis clustering, and Canonical Correspondence Analysis. Results Streptomyces species, Gram-positive bacteria, were commonly found in differing abundances in all samples. Gram-positive species were predominant in soils amended with vegetable green waste while Gram-negative bacteria were more abundant in samples with chemical fertilizer. Fungal abundance increased in poultry manure and chemical fertilizers. Conclusion Our findings suggested that organic matter recycling and composting resulted in the shifting of biodiversity in bacterial and fungal populations which might be associated with the availability of certain nutrient sources provided by the composting materials.

Societal Impact Statement Colombia is a “megadiverse” country with vast natural resources. A history of recent conflict means that information is only now being collected on the natural capital of regions that were previously unexplored. Better access to data, tools, and expertise is required for evidence‐supported decisions on the conservation of these resources. The development of a bespoke cyberinfrastructure could help fulfill this need by providing access to digital resources in a collaborative cyberenvironment. We outline key priorities and develop a reference framework for building cyberinfrastructure in Colombia. This framework could be applied to other fields and countries to promote knowledge exchange, scientific innovation, and socioeconomic growth.

Nummular keratitis is an inflammatory process of the cornea that is characterized by multiple sub-epithelial deposits, for which a variety of therapeutic approaches have been proposed. A retrospective review was performed using the medical records of patients diagnosed with nummular keratitis and treated with a combined intrastromal injection of ganciclovir and depot betamethasone between the years 2009 and 2017. A total of 21 eyes of 16 patients were finally included. Upon termination of the treatment, 18 eyes (85.71%) were asymptomatic. This improvement was maintained during a mean follow-up time of 22.90 months. Depot betamethasone mixed with ganciclovir by intrastromal application is a good alternative for the treatment of nummular keratitis.

BACKGROUND The inappropriate use of antibiotics has led to the accelerated growth of resistance to antibiotics. The search for new therapeutic strategies (i.e., antimicrobial peptides-AMPs) has thus become a pressing need. OBJECTIVE Characterising and evaluating Sarconesiopsis magellanica larval fat body-derived AMPs. METHODS Fat body extracts were analysed by reversed-phase high-performance liquid chromatography (RP-HPLC); mass spectrometry was used for characterising the primary structure of the AMPs so found. ProtParam (Expasy) was used for analysing the AMPs’ physico-chemical properties. Synthetic AMPs’ antibacterial activity was evaluated. FINDINGS Four new AMPs were obtained and called sarconesin III, IV, V and VI. Sarconesin III had an α-helix structure and sarconesins IV, V and VI had linear formations. Oligomer prediction highlighted peptide-peptide interactions, suggesting that sarconesins III, V and VI could form self-aggregations when in contact with the microbial membrane. AMPs synthesised from their native molecules’ sequences had potent activity against Gram-positive bacteria and, to a lesser extent, against Gram-negative and drug-resistant bacteria. Sarconesin VI was the most efficient AMP. None of the four synthetic AMPs had a cytotoxic effect. MAIN CONCLUSIONS S. magellanica larval fat body-derived antimicrobial peptides are an important source of AMPs and could be used in different antimicrobial therapies and overcoming bacterial resistance