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While central circuits governing sleep are well-studied, the contribution of signaling from peripheral tissues remains a critical yet less understood aspect of sleep regulation. The highly conserved RNA-binding protein Pumilio (Pum) is a post-transcriptional regulator expressed in multiple tissues that influence systemic physiology, but its role in modulating basal sleep from peripheral tissues has not been established. Although Pumilio’s function in central neurons has been linked to sleep homeostasis following deprivation, whether it regulates sleep through peripheral mechanisms remains unknown. Here, we use conditional genetic tools in the fruit fly Drosophila melanogaster to demonstrate that genetic manipulation of Pumilio targeting the intestinal stem cells (ISCs) and the endocrine corpus allatum (CA) regulates the transition to sleep. Reducing Pumilio function in either the ISCs or the CA independently and significantly accelerates nighttime sleep onset, while overexpression produces the opposite effect. This behavioral change is accompanied by widespread transcriptional alterations in the head, characterized by a robust upregulation of genes involved in cellular stress responses. Our findings reveal a previously unrecognized gut-endocrine-brain signaling axis and identify peripheral post-transcriptional regulation as a key input to the central control of sleep behavior.

Natural extracts possess several kinds of antioxidants (anthocyanins, betalains, thymol, carvacrol, and resveratrol) that have also demonstrated antimicrobial properties. In order to study these properties, extracts from cranberry, blueberry, beetroot, pomegranate, oregano, pitaya, and resveratrol (from grapes) were obtained. Growth inhibition tests of mesophilic aerobes, coliforms, and fungi were conducted in films prepared from the extracts in accordance with Mexican Official Norms (NOM). Optical properties such as transparency and opacity, mechanical properties, and pH were also analyzed in these materials. The films with beetroot, cranberry, and blueberry extracts demonstrated the best antimicrobial activity against various bacteria and fungi in comparison with unmodified chitosan–starch film. This study shows that the addition of antioxidants improved the antimicrobial performance of these films. It was also found that antimicrobial properties are inherent to the films. These polymers combined with the extracts effectively inhibit or reduce microorganism growth from human and environmental contact; therefore, previous sterilization could be unnecessary in comparison with traditional plastics. The presence of extracts decreased transmittance percentages at 280 and 400 nm, as well as the transparency values, while increasing their opacity values, providing better UV–VIS light barrier properties. Despite diminished glass transition temperatures (Tg), the values obtained are still adequate for food packaging applications.

The aim of this work is to analyze water sorption in hybrid polyester/glass fabric/jute fabric composites molded via compression and VARTM (Vacuum-Assisted Resin Transfer Molding). The laminates were produced with five different stacking sequences and subjected to water sorption testing at room temperature, 50 °C and 70 °C. This study consisted of two stages: experimental and theoretical stages. The composites had a fiber volume content ranging from 30% to 40%. Water absorption and diffusion coefficient in the hybrid composites were intermediate to those reinforced with a single type of fiber. There were no significant differences in these properties based on fiber arrangement once the composites reached saturation. Diffusion coefficient values were higher for specimens with jute fiber on at least one of the outer surfaces. Water sorption rates increased with higher immersion temperatures. The water sorption at saturation point was not affected by the manufacturing process. Among the hybrid composites, those with jute on the surfaces showed the highest diffusion coefficient, while those with glass on the surface had the lowest values. Higher diffusion coefficient values were observed at temperatures of 50 °C and 70 °C. The main influencing factors on the absorbed moisture content for composites are the presence and content of jute fibers in the system and the immersion temperature. The manufacturing process does not affect the water sorption at saturation point.

This paper investigates the mechanical stability and critical thickness of free-standing, ultrathin molten polyethylene films using Molecular Dynamics simulations. By comparing the “interfacial drying” and “film stretching” methodologies, this research establishes that both methods consistently identify a stability threshold where continuous films transition into fibrillar and void structures known as “crazes”. A key finding is that films at extremely reduced thicknesses exhibit an anisotropic pressure profile in their core—characterized by a positive normal pressure—which serves as a manifestation of positive disjoining pressure and a precursor to film transformation. Consequently, the study proposes a more rigorous stability criterion based on mechanical isotropy, which yields higher critical thickness values (approximately 6.5 nm at 373.15 K and 9.3 nm at 673.15 K) than those previously estimated from short-term (100 ns) visual observations. Ultimately, the work concludes that maintaining a negative disjoining pressure is fundamental to the structural integrity of these polymeric nanomaterials.

Males in Hymenopteran societies are understudied in many aspects and it is assumed that they only have a reproductive function. We studied the time budget of male honey bees, drones, using multiple methods. Changes in the activities of animals provide important information on biological clocks and their health. Yet, in nature, these changes are subtle and often unobservable without the development and use of modern technology. During the spring and summer mating season, drones emerge from the hive, perform orientation flights, and search for drone congregation areas for mating. This search may lead drones to return to their colony, drift to other colonies (vectoring diseases and parasites), or simply get lost to predation. In a low percentage of cases, the search is successful, and drones mate and die. Our objective was to describe the activity of Apis mellifera drones during the mating season in Northwestern Argentina using three methods: direct observation, video recording, and radio frequency identification (RFID). The use of RFID tagging allows the tracking of a bee for 24 h but does not reveal the detailed activity of drones. We quantified the average number of drones’ departure and arrival flights and the time outside the hive. All three methods confirmed that drones were mostly active in the afternoon. We found no differences in results between those obtained by direct observation and by video recording. RFID technology enabled us to discover previously unknown drone behavior such as activity at dawn and during the morning. We also discovered that drones may stay inside the hive for many days, even after initiation of search flights (up to four days). Likewise, we observed drones to leave the hive for several days to return later (up to three days). The three methods were complementary and should be considered for the study of bee drone activity, which may be associated with the diverse factors influencing hive health.

Honey bees are critical pollinators in ecosystems and agriculture, but their numbers have significantly declined. Declines in pollinator populations are thought to be due to multiple factors including habitat loss, climate change, increased vulnerability to disease and parasites, and pesticide use. Neonicotinoid pesticides are agonists of insect nicotinic cholinergic receptors, and sub-lethal exposures are linked to reduced honey bee hive survival. Honey bees are highly dependent on circadian clocks to regulate critical behaviors, such as foraging orientation and navigation, time-memory for food sources, sleep, and learning/memory processes. Because circadian clock neurons in insects receive light input through cholinergic signaling we tested for effects of neonicotinoids on honey bee circadian rhythms and sleep. Neonicotinoid ingestion by feeding over several days results in neonicotinoid accumulation in the bee brain, disrupts circadian rhythmicity in many individual bees, shifts the timing of behavioral circadian rhythms in bees that remain rhythmic, and impairs sleep. Neonicotinoids and light input act synergistically to disrupt bee circadian behavior, and neonicotinoids directly stimulate wake-promoting clock neurons in the fruit fly brain. Neonicotinoids disrupt honey bee circadian rhythms and sleep, likely by aberrant stimulation of clock neurons, to potentially impair honey bee navigation, time-memory, and social communication.

Hydroxyethylcellulose (HEC) is a biodegradable, biocompatible polymer which is responsive to the temperature and pH values that can be reached by the human body. Polyacrylamide (PAAm) is a biocompatible and absorbent material which is highly used as a Drug Delivery System (DDS) due to its swelling capacity. In this work, a composite of HEC and PAAm was synthesized at a ratio of 25/75 wt% in order to evaluate its use as a transdermal DDS for acetaminophen. Drug release tests were performed in a phosphate buffer solution (PBS) at 35, 37, and 39 °C. The Korsmeyer-Peppas model was presented as a mathematical optimization problem and solved by Differential Evolution (DE) algorithm. Additionally, drug release data was modelled by Multigene Symbolic Regression (MSR) based on Genetic Programming (GP) algorithm. A drug release mathematical model was generated by MSR. The model is capable to reliably describe the kinetics of acetaminophen release from HEC/PAAm and to predict the concentrations of drug that is released in times beyond the experiment runtime.

Bacterial cellulose (BC) has gained attention in recent years due to its high purity and multiple applications in the biomedical and pharmaceutical fields, and mothers of vinegar are a promising source of low-cost BC that can be easily obtained from any variety of vinegar. Silver nanoparticles (AgNPs) are known for their antimicrobial activity as well as their use as antiseptics on healing wounds. For this research, BC-AgNPs films were synthesized, and their antibacterial activity against Staphylococcus aureus and Escherichia coli was evaluated. The BC films were obtained from mothers of vinegar from two varieties (apple vinegar and cranberry vinegar) and were used as support for AgNPs at 5, 25, 41, 69, 116 and 324 ppm. All the films added with AgNPs achieved growth inhibition of 99–100% for both bacterial species, exhibiting values of antibacterial effectiveness ( R ) between 3.37 and 7.72. The BC-AgNPs films presented a slightly higher antibacterial activity against S. aureus , but the difference was negligible, and the composites were effective to inhibit the growth of both bacteria. The results show that the BC-AgNPs films synthesized from mothers of vinegar have potential for wound-healing purposes and that they are effective with silver concentrations as low as 5 ppm. Graphical Abstract

Asphalt performance improves with the incorporation of various additives and with the time factor. In this study, the effect of time on asphalt mixtures (AM) containing styrene–butadiene–styrene (SBS) and sargassum particles (SGP) is analyzed. The composites were prepared by the melt method, using five part hundred rubber (phr) of SGP and polymeric matrices of SBS with low and high vinyl content. The asphaltic mixtures were made with 3% percent by weight (wt%) of these composites, identified as high vinyl asphalt mix (AMH) and low vinyl asphalt mix (AML), respectively. Temperature sweep tests were carried out within linear viscoelastic region (LVR), with measurements taken at 1, 7, 14, and 82 days after mixing. The parameters studied include the viscoelastic behavior in the black diagrams, the effect of heavy traffic on the isochronous comples modulus-phase angle-temperature (G*)–δ–T curves, and the rutting factor with the parameter complex modulus between delta sine (G*/sin δ). In conclusion, the AMH asphalt mix shows the best rheological performance after 82 days of mixing. Graphical abstract

Classical Molecular Dynamics simulations were used to investigate the interfacial adsorption of supercritical ethane on ultrathin molten polyethylene films at various temperatures (298.15–448.15 K) and pressures (0.28–13.17 MPa). Ethane was found to accumulate preferentially at the film’s interfaces rather than dissolving into the film’s core. The ultra-thin, metastable films, studied at their mechanical stability limit, are composed of two overlapping interfaces. The films show some fractions of interfacial chains transiently desorbing from the film surface and entering the gas phase, which facilitates the accumulation of ethane at the interfaces. At 373.15 K and pressures between 0.29 MPa and 9.65 MPa, the combined film interfaces adsorb between 4.8 and 8.6 times more ethane than the amount solubilized in the central, bulk region of the film. Interfacial tension of the film decreases exponentially with increasing gas pressure of ethane and is primarily governed by inter-chain interactions at the interface. Minor contributions arise from the vibrational dynamics of polyethylene chain fractions that transiently desorb from the film surface. Furthermore, the solubility of ethane in the film’s bulk region exhibits a temperature-dependent inversion: at 298.15 K, the ethane density in the film’s center slightly exceeds that of the bulk gas, but this trend reverses at 373.15 K and becomes more pronounced as the temperature increases. This indicates a potential solubility transition temperature between 298.15 K and 373.15 K.