Speciation in Coastal Basins Driven by Staggered Headwater Captures: Dispersal of a Species Complex, Leporinus bahiensis, as Revealed by Genome-wide SNP Data.

Past sea level changes and geological instability along watershed boundaries have largely influenced fish distribution across coastal basins, either by dispersal via palaeodrainages now submerged or by headwater captures, respectively. Accordingly, the South American Atlantic coast encompasses several small and isolated drainages that share a similar species composition, representing a suitable model to infer historical processes. Leporinus bahiensis is a freshwater fish species widespread along adjacent coastal basins over narrow continental shelf with no evidence of palaeodrainage connections at low sea level periods. Therefore, this study aimed to reconstruct its evolutionary history to infer the role of headwater captures in the dispersal process. To accomplish this, we employed molecular-level phylogenetic and population structure analyses based on Sanger sequences (5 genes) and genome-wide SNP data. Phylogenetic trees based on Sanger data were inconclusive, but SNPs data did support the monophyletic status of L. bahiensis. Both COI and SNP data revealed structured populations according to each hydrographic basin. Species delimitation analyses revealed from 3 (COI) to 5 (multilocus approach) MOTUs, corresponding to the sampled basins. An intricate biogeographic scenario was inferred and supported by Approximate Bayesian Computation (ABC) analysis. Specifically, a staggered pattern was revealed and characterized by sequential headwater captures from basins adjacent to upland drainages into small coastal basins at different periods. These headwater captures resulted in dispersal throughout contiguous coastal basins, followed by deep genetic divergence among lineages. To decipher such recent divergences, as herein represented by L. bahiensis populations, we used genome-wide SNPs data. Indeed, the combined use of genome-wide SNPs data and ABC method allowed us to reconstruct the evolutionary history and speciation of L. bahiensis. This framework might be useful in disentangling the diversification process in other neotropical fishes subject to a reticulate geological history.

Influence of social support and stressful life events on adherence to colorectal cancer screening using faecal occult blood test in Spanish medium risk population.

INTRODUCTION: Colorectal cancer (CRC) is the second cause of cancer-related deaths worldwide. Five-year survival rate in Spain is 57%. The most important prognostic factor is the stage of the tumor at the diagnosis. CRC can be early diagnosed, but the adherence to screening programs is low (<50%). This study aims to ascertain the influence of social support and stressful life events on the adherence to the population screening of CRC with fecal occult blood test in Spanish average risk population. METHODS: Multicenter case-control study. We conducted a simple random sampling among individuals invited to participate in the colorectal cancer screening program. We analyzed epidemiological and social variables associated with lifestyle and behavioral factors. We performed a descriptive and a bivariant analyses and a logistic regression analysis. RESULTS: Four hundred and eight patients (237 cases and 171 controls) were included. Multivariant analyses showed independent association between higher adherence to the screening program and older age (OR: 1.06; 95% CI: 1.01-1.10), stable partner (OR: 1.77, 95% CI: 1.08-2.89) and wide social network (OR: 1.68; 95% CI: 1.07-2.66). Otherwise, lower adherence was associated to perceiving barriers to participate in the program (OR: 0.92; 95% CI: 0.88-0.96). We find a statistically significant association between lower adherence and high impact stressful life events in the bivariant analyses, and the tendency was maintained (OR: 0.63, 95% CI: 0.37-1.08) in the multivariant. CONCLUSION: Social variables decisively influence the adherence to colorectal cancer screening. The implementation of social interventions that improve social support, reduce impact of stressful life events and the design of screening programs that decrease the perceived barriers, will contribute to increase the participation on these programs. Secondary, the colorectal cancer diagnosis will be made in early-stages with the consequent mortality reduction.

Genomic Signatures of Divergent Ecological Strategies in a Recent Radiation of Neotropical Wild Cats.

Ecological differentiation among diverging species is an important component of the evolutionary process and can be investigated in rapid and recent radiations. Here, we use whole genome sequences of five species from the genus Leopardus, a recently diversified Neotropical lineage with species bearing distinctive morphological, ecological, and behavioral features, to investigate genome-wide diversity, comparative demographic history and signatures of positive selection. Our results show that divergent ecological strategies are reflected in genomic features, for example a generalist species shows historically larger effective population size and higher heterozygosity than habitat specialists. The demographic history of these cats seems to have been jointly driven by climate fluctuations and habitat specialization, with different ecological adaptations leading to distinct trajectories. Finally, a gene involved in vertebrate retinal neurogenesis (POU4F2) was found to be under positive selection in the margay, a cat with notoriously large eyes that are likely associated with its nocturnal and arboreal specializations.

Materials used to prevent adhesion, growth, and biofilm formation of Candida species.

The species of the Candida genus are opportunistic pathogenic fungi found in humans and are responsible for ∼80% of worldwide fungal infections. Aimed at diminishing and preventing Candida adhesion to cells or implanted devices in the human host, a large diversity of materials has been developed and functionalized that have attracted much interest. Furthermore, these materials have been focused almost exclusively on Candida albicans, followed by C. glabrata, C. parapsilosis, and C. tropicalis. Although an important diversity of materials has been synthesized to prevent adherence and formation of biofilms by Candida species, it is however important to evaluate the capacity of each material in terms of its property to diminish the adherence of Candida. These materials are discussed in this review.

In-house standards derived from doping peptides: Enzymatic and serum stability and degradation profile of GHRP and GHRH-related peptides.

Matrix effect and sample pretreatment significantly affect the percentage recovery of peptides in biological matrices, affecting the method robustness and accuracy. To counteract this effect, an internal standard (IS) is used; however, in most cases this is not available, which limits the analytical method. It is important to identify short peptides that can be used as ISs in the quantification of peptides in biological matrices. In this study, doping peptides GHRP-4, GHRP-5, GHRP-6, Sermorelin (1-11), Sermorelin (13-20) and Sermorelin (22-29) were synthesized using solid-phase peptide synthesis. Treatment with human blood, trypsin and chymotrypsin was used to determine the stability of the peptides. Products were evaluated using the high-performance liquid chromatography-diode array detector (HPLC-DAD) method. The analytical methodology and sample pretreatment were effective for the analysis of these molecules. A unique profile related to protein binding and enzymatic stability of each peptide was established. GHRP-4, GHRP-6 and Sermorelin (22-29) can be considered as in-house ISs as they were stable to enzyme and blood treatment and can be used for the quantification of peptides in biological samples. Peptides GHRP-6 and Sermorelin (22-29) were used to analyse a dimeric peptide (26 [F] LfcinB (20-30)2 ) in four different matrices to test these peptides as in-house IS.

A Validated HPLC-UV-ESI-IT-MS Method for the Quantification of Carnosol in Lepechinia mutica, a Medicinal Plant Endemic to Ecuador.

The diphenolic diterpene carnosol was isolated from several species of the family Lamiaceae, including Lepechinia mutica, a medicinal plant endemic to Ecuador. The compound has exhibited high antioxidant, anti-inflammatory, antimicrobial, neuroprotective, and antifungal properties, as well as promising cytotoxicity against prostate, breast, skin, leukemia, and human colon cancer cell lines. In this paper, we developed and validated a simple, accurate, and reliable analytical HPLC-UV-ESI-IT-MS method, carried out on a C18 column, which is potentially suitable to quantify carnosol in plant extracts. The procedure complied with the established ICH validation parameters of analytical range (linearity in the range of 0.19-5.64 µg/g dried leaves; REAVERGE = 4.9%; R2 = 0.99907), analysis repeatability (RSD = 2.8-3.6%), intermediate precision (RSD = 1.9-3.6%), accuracy (estimated as % carnosol recovery in the range of 81 to 108%), and robustness. Finally, the LOD (0.04 µg/mg) and LOQ (0.19 µg/mg) values of carnosol/dried leaves were determined. Using this validated method, the content of carnosol in L. mutica was estimated to be 0.81 ± 0.04 mg/g of dried leaves (0.081%).

Perceived barriers and benefits in the participation in faecal occult blood test colorectal cancer screening programme.

BACKGROUND: Colorectal cancer is the second cancer-related cause of death in the world. Tumour stage at diagnosis is the principal prognosis factor of survival. However, the participation in the programme is around 50%. The aim of the study was to identify the benefits and barriers perceived by the population when participating in a colorectal cancer screening programme with faecal occult blood test. METHODS: We carried out a cases-controls study with 408 participants. We analyzed epidemiological and social variables associated with lifestyle and behavioural factors based in the Health Belief Model. We conducted a descriptive analysis, and identified variables associated to adherence by a logistic regression. RESULTS: Variables independently associated with the participation in a colorectal cancer screening programme were age (OR 1.06; 95% CI: 1.01-1.11), having a stable partner (OR 1.96; 95% CI: 1.20-3.18), the level of education (OR 1.59; 95% CI: 1.02-2.47) and two of the barriers to participate in the faecal occult blood test screening: "you don't know how to do one" (OR=0.46; 95% CI: 0.23-0.93) and "it is not that important right now" (OR=0.43; 95% CI: 0.24-0.78). CONCLUSION: The existing barriers for screening with faecal occult blood test are the best factor predicting. This is relevant when designing the intervention programmes, as they should focus on reducing perceived barriers to increase the participation in colorectal cancer screening, thereby reducing colorectal cancer mortality.

Contribution of APOA5, APOC3, CETP, ABCA1 and SIK3 genetic variants to hypertriglyceridemia development in Mexican HIV-patients receiving antiretroviral therapy.

OBJECTIVE: To investigate the impact of single nucleotide polymorphisms (SNPs) from APOA5, APOC3, CETP, ATP binding cassette transporter A1 and SIK3 genes in the development of hypertriglyceridemia in HIV patients under antiretroviral therapy. MATERIAL AND METHODS: A case-control study was developed. Leukocytic genomic DNA was extracted and genotyping for SNPs rs662799, rs964184, rs5128, rs2854116, rs2854117, rs3764261, rs4149310, rs4149267 and rs139961185 was performed by real time-PCR using TaqMan allelic discrimination assays, in Mexican mestizo patients with HIV infection, with hypertriglyceridemia (>1.7 mmol/L) under antiretroviral therapy. Genetic variants were also investigated in a control group of normolipidemic HIV patients (≤ 1.7 mmol/L). Haplotypes and gene interactions were analyzed. RESULTS: A total of 602 HIV patients were genotyped (316 cases and 286 controls). Age and antiretroviral regimen based on protease inhibitors were associated with hypertriglyceridemia (P = 0.0001 and P = 0.0002. respectively). SNP rs964184 GG genotype in APOA5 gene exhibited the highest association with hypertriglyceridemia risk (OR, 3.2, 95% CI, 1.7-5.8, P = 0.0001); followed by SNP rs139961185 in SIK3 gene (OR = 2.3; (95% CI, 1.1-4.8; P = 0.03 for AA vs. AG genotype; and APOC3 rs5128 GG genotype, (OR, 2.2; 95% CI, 1.1-4.9; P = 0.04) under codominant models. These associations were maintained in the adjusted analysis by age and protease inhibitors based antiretroviral regimens. CONCLUSIONS: This study reveals an association between rs964184 in APOA5; rs5128 in APOC3 and rs139961185 in SIK3 and high triglyceride concentrations in Mexican HIV-patients receiving protease inhibitors. These genetic factors may influence the adverse effects related to antiretroviral therapy.

Intrinsic structure perspective for MIPS interfaces in two-dimensional systems of active Brownian particles.

Suspensions of active Brownian particles (ABPs) undergo motility-induced phase separation (MIPS) over a wide range of mean density and activity strength, which implies the spontaneous aggregation of particles due to the persistence of their direction of motion, even in the absence of an explicit attraction. Both similarities and qualitative differences have been obtained when the MIPS is analysed in the same terms as a liquid-gas phase coexistence in an equilibrium attractive system. Negative values of the mechanical surface tension have been reported, from the total forces across the interface, while stable fluctuations of the interfacial line could be interpreted as a positive capillary surface tension; in equilibrium liquid surfaces, these two magnitudes are equal. We present here the analysis of 2D-ABP interfaces in terms of the intrinsic density and force profiles, calculated with the particle distance to the instantaneous interfacial line. Our results provide new insight into the origin of MIPS from the local rectification of the random active force on the particles near the interface. As has been reported, this effect acts as an external potential that produces a pressure gradient across the interface, such that the mechanical surface tension of the MIPS cannot be described as that of equilibrium coexisting phases; however, our analysis shows that most of that effect comes from the tightly caged particles at the dense (inner) side of the MIPS interface, rather than from the free moving particles at the outer side that collide with the dense cluster. Moreover, a clear correlation appears between the decay of the hexatic order parameter at the dense slab and the end of the MIPS as the strength of the active force is lowered. We show that, using the strong active forces required for MIPS, the interfacial structure and properties are very similar for ABPs with purely repulsive interactions (the Weeks-Chandler-Andersen-Lennard-Jones (WCA-LJ) model truncated at its minimum) and when the interaction includes a range of the LJ attractive force.

A review of ferric citrate clinical studies, and the rationale and design of the Ferric Citrate and Chronic Kidney Disease in Children (FIT4KiD) trial.

Pediatric chronic kidney disease (CKD) is characterized by many co-morbidities, including impaired growth and development, CKD-mineral and bone disorder, anemia, dysregulated iron metabolism, and cardiovascular disease. In pediatric CKD cohorts, higher circulating concentrations of fibroblast growth factor 23 (FGF23) are associated with some of these adverse clinical outcomes, including CKD progression and left ventricular hypertrophy. It is hypothesized that lowering FGF23 levels will reduce the risk of these events and improve clinical outcomes. Reducing FGF23 levels in CKD may be accomplished by targeting two key stimuli of FGF23 production-dietary phosphate absorption and iron deficiency. Ferric citrate is approved for use as an enteral phosphate binder and iron replacement product in adults with CKD. Clinical trials in adult CKD cohorts have also demonstrated that ferric citrate decreases circulating FGF23 concentrations. This review outlines the possible deleterious effects of excess FGF23 in CKD, summarizes data from the adult CKD clinical trials of ferric citrate, and presents the Ferric Citrate and Chronic Kidney Disease in Children (FIT4KiD) study, a randomized, placebo-controlled trial to evaluate the effects of ferric citrate on FGF23 in pediatric patients with CKD stages 3-4 (ClinicalTrials.gov Identifier NCT04741646).

A GDPase/UDPase bifunctional enzyme from Candida albicans: purification and biochemical characterization.

The most frequently isolated human fungal pathogen is Candida albicans which is responsible for about 50% of all Candida infections. In healthy individuals, this organism resides as a part of the normal microbiota in equilibrium with the host. However, under certain conditions, particularly in immunocompromised patients, this opportunistic pathogen adheres to host cells causing serious systemic infections. Thus, much effort has been dedicated to the study of its physiology with emphasis on factors associated to pathogenicity. A representative analysis deals with the mechanisms of glycoprotein assembly as many cell surface antigens and other macromolecules that modulate the immune system fall within this chemical category. In this regard, studies of the terminal protein glycosylation stage which occurs in Golgi vesicles has led to the identification of nucleotidases that convert glycosyltransferase-generated dinucleotides into the corresponding mononucleotides, thus playing a double function: their activity prevent inhibition of further glycosyl transfer by the accumulation of dinucleotides and the resulting mononucleotides are exchanged by specific membrane transporters for equimolecular amounts of sugar donors from the cytosol. Here, using a simple protocol for protein separation we isolated a bifunctional nucleotidase from C. albicans active on GDP and UDP that was characterized in terms of its molecular mass, response to bivalent ions and other factors, substrate specificity and affinity. Results are discussed in terms of the similarities and differences of this nucleotidase with similar counterparts from other organisms thus contributing to the knowledge of a bifunctional diphosphatase not described before in C. albicans.

Detailed dynamics of discrete Gaussian semiflexible chains with arbitrary stiffness along the contour.

We revisit a model of semiflexible Gaussian chains proposed by Winkler et al., solve the dynamics of the discrete description of the model, and derive exact algebraic expressions for some of the most relevant dynamical observables, such as the mean-square displacement of individual monomers, the dynamic structure factor, the end-to-end vector relaxation, and the shear stress relaxation modulus. The mathematical expressions for the dynamic structure factor are verified by comparing them with results from Brownian dynamics simulations, reporting an excellent agreement. Then, we generalize the model to linear polymer chains with arbitrary stiffness. In particular, we focus on the case of a linear polymer with stiffness that changes linearly from one end of the chain to the other, and we study the same dynamical functions previously presented. We discuss different approaches to check whether a polymer has constant or heterogeneous stiffness along its contour. Finally, we provide expressions for the Lagrangian multipliers for Gaussian chains with variable stiffness and bond length, as well as for chains with torsion-like interactions. Overall, this work presents a new insight into a well-known model for semiflexible chains and provides tools that can be exploited to explore a much broader class of polymers or compare the predictions of the model with simulations of coarse-grained semiflexible polymers.

Dynamical anomalies and structural features of active Brownian particles characterized by two repulsive length scales.

In this work, we study a two-dimensional system composed by Active Brownian Particles (ABPs) interacting via a repulsive potential with two length scales-a soft shell and a hard core. Depending on the ratio between the strength of the soft shell barrier and the activity, we find two regimes: If this ratio is much larger or smaller than 1, the observed behavior is comparable with ABPs interacting via a single length scale potential. If this ratio is similar to 1, the two length scales are relevant for both structure and dynamical properties. On the structural side, when the system exhibits a motility induced phase separation, the dense phase is characterized by new and more complex structures compared with the hexatic phase observed in single length scale systems. From the dynamic analysis, we find, to our knowledge, the first manifestation of a dynamic heterogeneity in active particles, reminiscent of the glassy dynamics widely studied in passive colloids.

Homogeneous ice nucleation rates for mW and TIP4P/ICE models through Lattice Mold calculations.

Freezing of water is the most common liquid-to-crystal phase transition on Earth; however, despite its critical implications on climate change and cryopreservation among other disciplines, its characterization through experimental and computational techniques remains elusive. In this work, we make use of computer simulations to measure the nucleation rate (J) of water at normal pressure under different supercooling conditions, ranging from 215 to 240 K. We employ two different water models: mW, a coarse-grained potential for water, and TIP4P/ICE, an atomistic nonpolarizable water model that provides one of the most accurate representations of the different ice phases. To evaluate J, we apply the Lattice Mold technique, a computational method based on the use of molds to induce the nucleus formation from the metastable liquid under conditions at which observing spontaneous nucleation would be unfeasible. With this method, we obtain estimates of the nucleation rate for ice Ih and Ic and a stacking mixture of ice Ih/Ic, reaching consensus with most of the previously reported rates, although differing with some others. Furthermore, we confirm that the predicted nucleation rates obtained by the TIP4P/ICE model are in better agreement with experimental data than those obtained through the mW potential. Taken together, our study provides a reliable methodology to measure nucleation rates in a simple and computationally efficient manner that contributes to benchmarking the freezing behavior of two popular water models.

The impact of the COVID-19 pandemic on the mental health of healthcare workers: study protocol for the COVID-19 HEalth caRe wOrkErS (HEROES) study.

BACKGROUND: Preliminary country-specific reports suggest that the COVID-19 pandemic has a negative impact on the mental health of the healthcare workforce. In this paper, we summarize the protocol of the COVID-19 HEalth caRe wOrkErS (HEROES) study, an ongoing, global initiative, aimed to describe and track longitudinal trajectories of mental health symptoms and disorders among health care workers at different phases of the pandemic across a wide range of countries in Latin America, Europe, Africa, Middle-East, and Asia. METHODS: Participants from various settings, including primary care clinics, hospitals, nursing homes, and mental health facilities, are being enrolled. In 26 countries, we are using a similar study design with harmonized measures to capture data on COVID-19 related exposures and variables of interest during two years of follow-up. Exposures include potential stressors related to working in healthcare during the COVID-19 pandemic, as well as sociodemographic and clinical factors. Primary outcomes of interest include mental health variables such as psychological distress, depressive symptoms, and posttraumatic stress disorders. Other domains of interest include potentially mediating or moderating influences such as workplace conditions, trust in the government, and the country's income level. RESULTS: As of August 2021, ~ 34,000 health workers have been recruited. A general characterization of the recruited samples by sociodemographic and workplace variables is presented. Most participating countries have identified several health facilities where they can identify denominators and attain acceptable response rates. Of the 26 countries, 22 are collecting data and 2 plan to start shortly. CONCLUSIONS: This is one of the most extensive global studies on the mental health of healthcare workers during the COVID-19 pandemic, including a variety of countries with diverse economic realities and different levels of severity of pandemic and management. Moreover, unlike most previous studies, we included workers (clinical and non-clinical staff) in a wide range of settings.

Rawl's questionnaire spanish validation for colorectal cancer screening with faecal occult blood testing. / Validación al castellano del cuestionario Rawl de cribado de cáncer colorrectal con sangre oculta en heces.

INTRODUCTION: Colorectal cancer 5-years-survival is 57%, partway due to a low rate of participation in screening programmes. Instruments analyzing causes of low adherence are needed. OBJECTIVE: To evaluate the validity and internal consistency of the Spanish version of Rawl's Questionnaire for the screening of colorectal cancer by faecal occult blood testing. TYPE OF STUDY: Questionnaire validation methodology. LOCATION: Three Primary Care Centres in Valencia. VARIABLES: Age, sex, civil status, educational level, social class, smoking, alcohol consumption, body mass index, personal and family history of cancer. RESULTS: We analyzed 408 individuals (237 cases and 171 controls). Mean age was 59.45 years (SD 5.17). Internal consistency of all variables reached a Cronbach's alfa of 0.796. The Cronbach's alfa benefit dimension of the screening was 0.871 and for the barrier dimension of the screening it was 0.817. Intraclass correlation coefficients of the test-retest for the benefit dimension of the screening was 0.809 (CI 95% 0.606-0.913) and 0.499 (CI 95% 0.126-0.750) for the barrier dimension. CONCLUSION: The Spanish version of Rawl's Questionnaire is valid, reliable and reproducible, so we have this validated instrument with which to identify barriers and benefits in a colorectal screening programme in Spain.

'RNA modulation of transport properties and stability in phase-separated condensates.

One of the key mechanisms employed by cells to control their spatiotemporal organization is the formation and dissolution of phase-separated condensates. The balance between condensate assembly and disassembly can be critically regulated by the presence of RNA. In this work, we use a chemically-accurate sequence-dependent coarse-grained model for proteins and RNA to unravel the impact of RNA in modulating the transport properties and stability of biomolecular condensates. We explore the phase behavior of several RNA-binding proteins such as FUS, hnRNPA1, and TDP-43 proteins along with that of their corresponding prion-like domains and RNA recognition motifs from absence to moderately high RNA concentration. By characterizing the phase diagram, key molecular interactions, surface tension, and transport properties of the condensates, we report a dual RNA-induced behavior: on the one hand, RNA enhances phase separation at low concentration as long as the RNA radius of gyration is comparable to that of the proteins, whereas at high concentration, it inhibits the ability of proteins to self-assemble independently of its length. On the other hand, along with the stability modulation, the viscosity of the condensates can be considerably reduced at high RNA concentration as long as the length of the RNA chains is shorter than that of the proteins. Conversely, long RNA strands increase viscosity even at high concentration, but barely modify protein self-diffusion which mainly depends on RNA concentration and on the effect RNA has on droplet density. On the whole, our work rationalizes the different routes by which RNA can regulate phase separation and condensate dynamics, as well as the subsequent aberrant rigidification implicated in the emergence of various neuropathologies and age-related diseases.

Responses of Sporothrix globosa to the cell wall perturbing agents Congo Red and Calcofluor White.

It is well documented that disturbance of cell surface by some agents triggers compensatory responses aimed to maintain the cell wall integrity in fungi and other organisms. Here, the thermodimorphic fungus Sporothrix globosa, a member of the pathogenic clade of the Sporothrix complex, was propagated in yeast-peptone-dextrose medium under conditions to obtain the mycelium (pH 4.5, 27-28 °C) or the yeast (pH 7.8, 32-34 °C) morphotypes in the absence and presence of the wall-interacting dyes Congo Red (CR) and Calcofluor White (CFW) either alone or in combination. After different periods of time, growth, cell morphology and activity of glucosamine-6-phosphate synthase (GlcN-6-P synthase), an ubiquitous enzyme that plays a crucial role in cell wall biogenesis, were determined. CR and to a lower extent CFW affected growth and morphology of both fungal morphotypes and significantly increased enzyme activity. Notoriously, CR or CR in combination with CFW induced the transient conversion of yeasts into conidia-forming filamentous cells even under culture conditions adjusted for yeast development, most likely as a strategy to evade the noxious effect of the dye. After sometime, hypha returned to yeast cells. An hypothetical model to explain the effect of CR on morphology and enzyme activity based on the possible role of membrane-spanning proteins known as mechanosensors is proposed. Results are discussed in terms of the fungal responses to cell wall damage.

Characterization of MIPS in a suspension of repulsive active Brownian particles through dynamical features.

We study a two-dimensional system composed by Active Brownian Particles (ABPs), focusing on the onset of Motility Induced Phase Separation (MIPS), by means of molecular dynamics simulations. For a pure hard-disk system with no translational diffusion, the phase diagram would be completely determined by their density and Péclet number. In our model, two additional effects are present: translational noise and the overlap of particles; we study the effects of both in the phase space. As we show, the second effect can be mitigated if we use, instead of the standard Weeks-Chandler-Andersen potential, a stiffer potential: the pseudo-hard sphere potential. Moreover, in determining the boundary of our phase space, we explore different approaches to detect MIPS and conclude that observing dynamical features, via the non-Gaussian parameter, is more efficient than observing structural ones, such as through the local density distribution function. We also demonstrate that the Vogel-Fulcher equation successfully reproduces the decay of the diffusion as a function of density, with the exception of very high densities. Thus, in this regard, the ABP system behaves similar to a fragile glass.

Chemical Composition and Anticholinesterase Activity of the Essential Oil of Leaves and Flowers from the Ecuadorian Plant Lepechinia paniculata (Kunth) Epling.

This work aimed to study the chemical composition, cholinesterase inhibitory activity, and enantiomeric analysis of the essential oil from the aerial parts (leaves and flowers) of the plant Lepechinia paniculata (Kunth) Epling from Ecuador. The essential oil (EO) was obtained through steam distillation. The chemical composition of the oil was evaluated by gas chromatography, coupled to mass spectrometry (GC-MS) and a flame ionization detector (GC-FID). The analyses led to the identification of 69 compounds in total, of which 40 were found in the leaves and 29 were found in the flowers of the plant. The major components found in the oil were 1,8-Cineole, ß-Pinene, δ-3-Carene, α-Pinene, (E)-Caryophyllene, Guaiol, and ß-Phellandrene. Flower essential oil showed interesting selective inhibitory activity against both enzymes AChE (28.2 ± 1.8 2 µg/mL) and BuChE (28.8 ± 1.5 µg/mL). By contrast, the EO of the leaves showed moderate mean inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), with IC50 values of 38.2 ± 2.9 µg/mL and 47.4 ± 2.3 µg/mL, respectively.