Evolutionary modifications of Astyanax larval prey capture (LPC) in a dark environment

Feeding strategies of an organism depend on the multimodal sensory processing that most efficiently integrates available visual,chemosensory,and/or mechanoreceptive cues as part of their environmental adaptation.The blind cavefish morph of Astyanax mexicanus has developed sensory-dependent behaviors to find food more efficiently than their eyed,surface-morph counterparts while in darkness.In the absence of light,adult cavefish have evolved enhanced behaviors,such as vibration attraction behavior(VAB),and changes in feeding angle.Here,we identified evolved differences in cavefish larval prey capture(LPC)behavior.In the dark,LPC is more efficient in cavefish than in surface fish.Furthermore,different cave populations express laterality in their LPC and strike towards prey preferentially located on their left or right sides.This suggests the occurrence,to some extent,of divergent LPC evolution among cave populations.While LPC can be triggered exclusively by a vibration stimulus in both surface and cavefish,we provide evidence that LPC is,at least partially,a multimodal sensory process different from adult VAB.We also found that a lack of food may exacerbate the laterality of LPC.Thus,we proposed a mathematical model for explaining laterality based on a balance between:(1)enlarged range of foraging field(behavioral or perceptive)due to asymmetry,(2)food abundance,and(3)disadvantages caused by laterality(unequal lateral hydrodynamic resistance when swimming,allocation of resources for the brain and receptors,and predator escape).

A Numerical Study of Several Species Population Models

This work considers a special case of Lotka-Volterra equations, which means that in the system of two ordinary differential equations, we take the four parameters equal to one. The reason is that we want just to illustrate the procedure to reduce that system to only one ordinary differential equation, such that we know its analytical solution. This idea will be applied to study the relations between a system of three ordinary differential equations, and a couple of partial differential equations. Lotka-Volterra equations are solved numerically by a fourth-order predictor-corrector method, which is initialized by an improved Euler method with a rather small time step because it is only a second-order algorithm. Then, it is proposed a model with three species, defined by ordinary differential equations.

Effect of Sleep Hygiene Orientation on Social Cognition Impairments Due to Chronic Sleep Restriction in Mexican Medical Residents

Introduction: Sleep is critical to human physiological function, cognitive performance, and emotional regulation. Healthcare personnel, especially physicians, are chronically exposed to long working hours, which are often accompanied by decreased sleep time. Clinical evidence indicates that these conditions affect their cognitive function and professional practice, but researchers in the field have not sufficiently explored the possible effects of reductions in sleep time on social cognition. Objective: The aim of this is to further explore the effects of sleep restriction among medical residents, the specific impairments in social cognition that it produces, and the effects of a sleep hygiene orientation on those impairments. Method: There were 124 medical residents (50 males, 74 females) who completed a daily sleep/work log, a battery of sleep tests/questionnaires, and neuropsychological evaluations. The participants then received a short course (8 hours) on basic concepts of sleep hygiene and sleep psychoeducation. Once the course was completed, participants filled out the questionnaires again. Results: The results indicate that sleep disturbances in medical residents were associated with severe neurocognitive and social cognition impairments. After the sleep hygiene intervention, neuropsychological function and sleep parameters improved, awareness increased, and social cognition performance significantly improved. Conclusion: Using sleep psychoeducation and sleep hygiene intervention in medical residents is a simple strategy to mitigate the effects of sleep restriction.

Modifi cation of sleep architecture in an animal model of experimental cirrhosis

AIM： To analyze the polygraphic sleep patterns during cirrhosis progression in a rat model by repeated CCh administration. METHODS： Male Wistar rats received three weekly injections of CCl4 for 11 wk, and were analyzed before and during the induction of cirrhosis. Rats were im- planted with electrodes to record their sleep patterns. Polygraph recordings were made weekly over 11 wk for 8 h, during the light period. After a basal recording, rats received three weekly injections of CCl4. Histological confirmation of cirrhosis was performed after 11 wk. RESULTS： The results showed a progressive decrease in total wake time that reached statistical significance from the second week of treatment. In addition, there was an increase in total time of slow wave sleep （SWS）Ⅱ and rapid eye movement sleep （REM sleep） in most of the 11 wk. SWS I showed no significant variations. During the final weeks, a significant increase in REM sleep frequency was also observed. Histological analyses of the livers showed unequivocal signs of cirrhosis. CONCLUSION： These data suggest that hepatic failure produced by CCh administration is capable of modifying the sleep pattern even after only a few doses.

Transcraneal Magnetic Stimulation Improves Sleep Parameters in Patients Affected with Imsomnia Associated to Electroencephalographic Abnormalities

Insomnia is one of the most frequently observed sleep disorders, affecting nearly 10% of the general population. It has multiple etiological factors. Recently, it has been reported that EEG abnormalities are associated with insomnia in patients previously diagnosed as idiopathic insomniacs. In addition, transcranial magnetic stimulation (TMS) has shown to be effective in the treatment of disorders characterized by neural hyper-excitability. Method: In the present study, patients with insomnia and EEG abnormalities were submitted to slow repetitive trans-cranial magnetic stimulation, for 15 minutes daily during 10 days. Polysomnographic recordings were performed before and after TMS. Results: The results indicate that the presence of EEG abnormalities significantly decreased after TMS. In addition, most of the sleep parameters showed significant improvement. Conclusions: These data support the notion that TMS is a reliable therapeutic tool for patients affected with abnormalities linked to neuronal hyper-excitability.

Insights into myelin dysfunction in schizophrenia and bipolar disorder

Schizophrenia and bipolar disorder are disabling psychiatric disorders with a worldwide prevalence of approximately 1%.Both disorders present chronic and deteriorating prognoses that impose a large burden,not only on patients but also on society and health systems.These mental illnesses share several clinical and neurobiological traits;of these traits,oligodendroglial dysfunction and alterations to white matter(WM)tracts could underlie the disconnection between brain regions related to their symptomatic domains.WM is mainly composed of heavily myelinated axons and glial cells.Myelin internodes are discrete axon-wrapping membrane sheaths formed by oligodendrocyte processes.Myelin ensheathment allows fast and efficient conduction of nerve impulses through the nodes of Ranvier,improving the overall function of neuronal circuits.Rapid and precisely synchronized nerve impulse conduction through fibers that connect distant brain structures is crucial for higher-level functions,such as cognition,memory,mood,and language.Several cellular and subcellular anomalies related to myelin and oligodendrocytes have been found in postmortem samples from patients with schizophrenia or bipolar disorder,and neuroimaging techniques have revealed consistent alterations at the macroscale connectomic level in both disorders.In this work,evidence regarding these multilevel alterations in oligodendrocytes and myelinated tracts is discussed,and the involvement of proteins in key functions of the oligodendroglial lineage,such as oligodendrogenesis and myelination,is highlighted.The molecular components of the axo-myelin unit could be important targets for novel therapeutic approaches to schizophrenia and bipolar disorder.

Vigorous,but differential mononuclear cell response of cirrhotic patients to bacterial ligands

AIM： To study the role of gram-positive and gram-negative bacteria in the pathogenesis of liver injury, specifically the activation of inflammatory mediators. METHODS： Peripheral blood mononuclear cells of 20 out-patients were studied, 10 of them with cirrhosis,Peripheral blood mononuclear cells were isolated and exposed to lipopolysaccharide or lipoteichoic acid. CD14, Toll-like receptor 2 and 4 expression was determined by flow cytometry, and tumor necrosis factor （TNF） α, interleukin （1L）-1β, IL-6, IL-12 and IL-10 secretion in su- pernatants was determined by ELISA. RESULTS： Higher CD14, Toll-like receptor 2 and 4 expression was observed in peripheral blood mononudear cells from cirrhotic patients, （P 〈 0.01, P 〈 0.006, P 〈 0.111） respectively. Lipopolysaccharide and lipoteichoic acid induced a further increase in CD14 expression （P 〈 0.111 lipopolysaccharide, P 〈 0.013 lipoteichoic acid）, and a decrease in Toll-like receptor 2 （P 〈 0.008 lipopolysaccharide, P 〈 0.008 lipoteichoic acid） and Toll-like receptor 4 （P 〈 0.008 lipopolysaccharide, P 〈 0.028 li- poteichoic acid） expression. With the exception of TNFα, absolute cytokine secretion of peripheral blood mononuclear cells was lower in cirrhotic patients under nonexposure conditions （P 〈 0.070 IL-6, P 〈 0.009 IL-1]5, P 〈 0.022 IL-12）. Once exposed to lipopolysaccharide or lipoteichoic acid, absolute cytokine secretion of peripheral blood mononuclear cells was similar in cirrhotic and non-cirrhotic patients, determining a more vigorous response in the former （P 〈 0.005 TNFα, IL-1β, IL-6, IL-2 and IL-10 lipopolysaccharide; P 〈 0.037 TNFα; P 〈 0.006 IL-113; P 〈 0.005 IL-6; P 〈 0.007 IL-12; P 〈 0.014 IL-10 lipoteichoic acid）. Response of peripheral blood mononuclear cells was more intense after lipopolysaccharide than after lipoteichoic acid exposure. CONCLUSION： Peripheral blood mononuclear cells of cirrhotic patients are able to respond to a sudden bacterial ligand exposure, particularly lipopolysaccharide, suggesting that immune regulation mechanisms are still present.

Electrochemical nucleation and growth of aluminum nanoparticles and leaf-like flat microstructures from reline deep eutectic solvent: Effect of temperature and angular speed of working electrode

The main objective of this work was to use reline deep eutectic solvent,containing Al(III)ions,for the electrochemical study of the nucleation and growth of aluminum onto a glassy carbon electrode at different temperatures and angular speeds(ω)of the working electrode.In order to fulfill this,electrochemical and surface characterization techniques were used.It was found that as temperature increased,the onset of the Al(III)DES reduction occurred at less negative potentials while the current peak of the voltammograms increased.These indicate that Al deposition thermodynamics and kinetics were favored.Practically,no anodic current was detected due to Al passivation by Al(OH)_(3)(s)andγ-Al_(2)O_(3)(s).Atω=0 r/min,the Al deposition chronoamperograms were analyzed by a theoretical model comprising Al 3D diffusion-controlled nucleation and growth and residual water reduction.However,those recorded at different angular speeds were analyzed with a theoretical model where adsorption−desorption and diffusion-controlled nucleation−growth occurred simultaneously.The deposits were characterized by SEM,EDX,XPS and XRD.Atω=0 r/min,formation of well distributed nanoparticles((78.1±9.5)nm)was observed,while atω=900 r/min the deposit was formed by multiple 10μm diameter leaf-like flat microstructures,composed by Al,Al(OH)_(3)(s)andγ-A2O3(s).

New Records of Marine Macroalgae on the Caribbean on Coast of Costa Rica

The results obtained in this study highlight that further the macroalgae diversity in this region is even higher than what is reported to date. Here we present eight new records of marine macroalgae collected from the Caribbean coast of Costa Rica between March 2011 and May 2019. The morphological characteristics of Bryocladia cuspidata, Ceratodictyon variabile, Gracilaria hayi, Padina boergesenii, Zonaria tournefortii, Sargassum furcatum, Chaetomorpha aerea, and Bryopsis pennata var. secunda are described. The genera Bryocladia and Zonaria are reported for the first time for this region.

Interaction of Acaena elongata L.with Arbuscular Mycorrhizal Fungi under Phosphorus Limitation Conditions in a Temperate Forest

The aim of this study was to analyze the performance of Acaena elongata colonized by arbuscular mycorrhizal fungi(AMF)to different phosphorus(P)concentrations,as a measure of AMF dependency.A.elongata,is a species from soils where P availability is limited,such as temperate forests.Our research questions were:1)How do different P concentrations affect the AMF association in Acaena elongata,and 2)How does the AMF association influence A.elongata’s growth under different P concentrations?A.elongata’s growth,P content in plant tissue,AMF colonization and dependency were measured under four P concentrations:control(0 g P kg^(-1)),low(0.05 g P kg^(-1)),intermediate(0.2 g P kg^(-1))and high(2 g P kg^(-1))in different harvests.A complete randomized block design was applied.A.elongata’s growth was higher under-AMF in intermediate and high P concentrations,and the lowest growth corresponded to+AMF in the low and intermediate P concentration.We observed a negative effect on the root biomass under+AMF in intermediate P concentration,while the P concentration had a positive effect on the leaf area ratio.The AMF colonization in A.elongata decreased in the highest P concentration and it was favored under intermediate P concentration;while the low and the high concentrations generated a cost-benefit imbalance.Our results suggest that the performance of some plant species in soils with low P availability may not be favored by their association with AMF,but a synergy between AMF and intermediate P concentrations might drive A.elongata’s growth.

Unbiased Diffusion to Escape Complex Geometries: Is Reduction to Effective One-Dimensional Description Adequate to Assess Narrow Escape Times?

This study is devoted to unbiased diffusion of point Brownian particles inside a tube of varying cross-section (see Figure 1). An expression for the mean survival time, , of the particles inside the tube is obtained in terms of the bulk diffusion constant, D0 and the system’s geometrical parameters, namely, the tube’s axial semi-length, L, the minor radius, , and the slope of the tube’s wall, . Our expression for correctly retrieves the limit behavior of the system under several conditions. We ran Monte Carlo numerical simulations to compute the mean survival time by averaging the survival time of 5 × 104 trajectories, with time step t = 10-6, D0 = 1, and L = 1. The simulations show good agreement with our model. When the geometrical parameters of this system are varied while keeping constant the tube’s enclosed volume, it resembles the problems of Narrow Escape Time (J. Chem. Phys. 116(22), 9574 (2007)). A previous study on the use of the reduction to effective one-dimension technique (J. Mod. Phys. 2, 284 (2011)) in complex geometries has shown excellent agreement between the theoretical model and numerical simulations. However, in this particular system, the general assumptions of the Hill problem are seemingly inapplicable. The expression obtained shows good agreement with our simulations when 0 ≤ ≤ 1, but fails when grows larger. On the other hand, some errors are found when 0, but the expression holds reasonably well for a broad range of values of . These comparisons between simulations and theoretical predictions, and the expressions obtained for , are the main results of this work.

Phytochemical Composition, Anti-Inflammatory and Cytotoxic Activities of Chloroform Extract of <i>Senna crotalarioides</i>Kunth

Senna crotalarioides is used in traditional medicine to treat inflammation. The aim of this work was to investigate the anti-inflammatory and cytotoxic activities and the possible mechanism of action of the chloroform extract washed with hexane of S. crotalarioides (CESC). The anti-inflammatory effect was tested on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice. The levels of TNF-α, IL-1β, IL-6 and IL-10 were determined in macrophages J774A.1 stimulated by lipopolysaccharide (LPS). The cytotoxic activity was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay against six human cancer cell lines: HeLa (cervical cancer), SKLU-1 and A549 (lung cancer), LNCaP (prostate cancer), SW620 (colon cancer) and MCF7 (breast cancer). The composition of the CESC was determined by GC-MS analysis, and standardized by HPLC-ELSD with ursolic acid as the phytochemical marker. CESC inhibited ear edema 61.45%. In chronic ear edema, CESC diminished the inflammation by 53.77%. CESC decreased TNF-α, IL-1β and IL-6 concentrations, and increased the concentration of IL-10. The extract showed IC50 values on HeLa, SKLU-1, A549, LNCaP, SW620 and MCF7 by 48, 21, 8.16, 6.82, 1.81, 4.06 and 12.5 μg/mL, respectively. The main components were ursolic acid, 1-octacosanol, stigmasterol, β-sitosterol, 1-triacontanol, (Z, Z) hexadec-9-enoic acid octadec-9-enyl ester. CESC might be useful for developing a phytomedicine with anti-inflammatory and cytotoxic activities.

Molecular Assessment of Athecate Dinoflagellates of the Order Gymnodiniales (Dinophyceae) in Todos Santos Bay, Baja California México

The Gymnodiniales are the most important group of athecate dinoflagellates both for its abundance and distribution and for the harmful potential of several of its species. Although morphologically it is well known, phylogenetically it has been very little studied. HABs impact important coastal activities in Todos Santos Bay, so a detailed characterization of potentially toxic phytoplankton species is crucial in monitoring surveys. Therefore, the aim of the present study was to carry out a molecular assessment to the morphospecies of Gymnodiniales currently recorded in Todos Santos Bay, from which discussed their phylogenetic relationships. 120 samples were obtained from monthly samplings during 2019 to 2020. For all of them, 18 s small subunit (SSU) and 28 s large subunit (LSU) genes of rDNA were amplified and sequenced using single-cell PCR. Also, they were photographed. A phylogenetic analysis was performed on MrBayes from the combined 18 s - 28 s data set. The presence of 15 phylogenetic entities was confirmed, four of which constituted new records for the Mexican Pacific, as well as three harmful species, one toxic and two bloom-forming. Our molecular results evidenced the need to re-evaluate the current taxonomic system of athecate dinoflagellates at all hierarchical levels, integrating them with morphological evidence without preponderance of this criterion over taxonomic decisions.

Sleep Deprivation Affects Working Memory in Low but Not in High Complexity for the N-Back Test

Sleep clearly influences learning and memory since sleep deprivation and stress impairs both cognitive processes. Working memory is an essential cognitive process and refers to a short-term holding of incoming information required to update the long-term mnemonic storage and to manipulate new elements in order to solve problems and make decisions. Nevertheless, the influence of sleep deprivation on working memory has scarcely been studied. In this study we evaluated working memory using the N-back test after increasing periods of wakefulness. Healthy young males were kept awake for 36 hours and the two N-back tasks with low (1-Back) and high (3-Back) levels of complexity were applied every 6 hours. Additionally, salivary cortisol was determined along the study. Unlike the control non-deprived participants, the sleep deprived volunteers showed a significant decrease in their efficiency to solve the 1-Back task after 24 hours of sleep deprivation. However, no differences were observed after 30 and 36 hours of sleep deprivation. Concerning the 3-Back task no differences were observed after sleep deprivation. Regarding reaction time, the deprived group manifested slower responses for the 1-Back task and for the 3-Back task after 30 hours and 36 hours of sleep deprivation, respectively. Cortisol levels presented the normal daily oscillation and no differences were observed between groups. This data suggests that sleep deprivation affects basal states of attention instead of working memory while performing simple tasks. The impact of sleep deprivation on the cognitive performance depends on the moment of day when the task is applied and the complexity of the tests used to assess these mnemonic skills.

Absence of Fruit Mexican Fly (<i>Anastrepha ludens</i>) in Pitaya de Mayo (<i>Stenocereus pruinosus</i>)

Pitaya de mayo (Stenocereus pruinosus) exportation is considered feasible especially to the United States of America (USA) using the adequate preservation and transportation techniques. One of the exportation requirements is that pitayas, as well as any other tropical fruits, have to be free from Mexican fruit fly contamination and certified by the Food National Sanitary, Iniquity, and Quality Service. This review proved that this fruit is not attacked by the Mexican fruit fly A. ludens or any other Anastrepha species. The fruit fly may be found in some States of Mexican Republic such as some tropical regions but not in the semi-arid regions where cacti fruits are grown.

Memory AND effector cells in children with bacterial infections of the gastrointestinal and respiratory tracts

Infections in infants and children under five years of age are a public health in México and are one of the major causes of death. Methods In this study, lymphocyte immunophenotyping for CD3+ (T-cells), CD3+CD4+, CD3+CD8+, CD3+CD19+, CD3+CD16/56+, CD45RA+, CD45RO+, CD62L- and CD28- were determined in the whole blood of gastrointestinal and respiratory bacterial infected children, using a four-color flow cytometry technique. Results: Our data showed that the percentages and the absolute numbers of monocytes and granulocytes are increased in infected children, when compared to the control group. Similarly, we observed increases in the percentages of B lymphocytes, CD8+ cells, memory T cells (CD4+CD45RO+ and CD8+CD45RO+) and effector lymphocytes (CD4+CD62L? and CD8+CD28?) in infected children compared with the control group. In contrast, naive T cells were decreased in the bacterial infected children relative to the control group. Additionally, we used ELISA assays to identify the pathogen agent in gastrointestinal and respiratory infection. Comparing different types of infection, we found that the children with respiratory bacterial infections had higher percentages of B lymphocytes, and cytotoxic lymphocytes (CD8+CD28-);and the children with gastrointestinal infections had higher percentages of CD3+ lymphocytes and effector cells (CD4+CD62L-). Conclusions The increase in B lymphocytes and CD8+CD28- cells in the children with respiratory infections and the increase of T lymphocytes and CD4+CD62L- cells in the children with gastrointestinal bacterial infections indicate that both cellular and humoral responses coincide, and both responses are necessary for eliminating the pathogen.

Hydrolysis of Trivalent Holmium in Aqueous Solutions of 2 M Ionic Strength by Spectrophotometric and Potentiometric Methods

The first hydrolysis constants of trivalent holmium in 2 M NaClO4 and 2 M NaCl at 303 K and in CO2 free conditions were determined. The pCH borderlines of precipitation and first hydrolysis were determined by means of a spectrophotometric method and last one with the program SQUAD. Independently, the stability constant for the first hydrolytic species was determined, by means of potentiometric pH titrations whose data were treated with the program SUPERQUAD. The hydrolysis constants obtained were: ?and . These values attained by both methods are the same. The log10β1,Cl constants for the species HoCl2+ was also calculated for 2 M ionic strength and 303 K from the hydrolysis constant obtained in both perchlorate and chloride media. This value was logβ1,Cl = -0.56.

Use of IVF and ET in Mexican Criollo Sheep (Ovis aries): Immediate and Delayed Embryo Transfers

There is little information in the scientific literature concerning sheep pregnancy and lambing success with regard to the timeframe from when in vitro produced embryos are transported to the designated location for embryo transfer (ET). The aim of this study was to transfer in vitro produced embryos under two different conditions that could typically occur using the aforementioned assisted reproductive techniques (ARTs). Abattoir ovaries were used to procure oocytes for in vitro embryo production and subsequent transfer to synchronized ewes. The study consisted of two experiments: Experiment 1 (Exp1)—embryos taken from the laboratory to a nearby surgical room for immediate ET, and Experiment 2 (Exp2)—ET after 5 hours (h) of transport to a rural farm. Lambing in relation to detected pregnancies, births compared to pregnancies, and the proportion of twin offspring were all higher in Exp2. Notably, in both Exp1 and Exp2, there was not a significant difference (P > 0.05) between the number of embryos transferred, i.e., 3 versus 4, respectively, and the number of ewes that underwent parturition in each group. Also, in both experiments there was not a significant difference (P > 0.05) in the number of ewes that underwent parturition based on the number (i.e., ≥1) of corpora lutea present. The results of the present study demonstrate the importance of evaluating different conditions when applying ARTs, as there are many variables that can influence the outcome. Importantly, Exp2 results show that ovine ET in places located far away from the embryo production site can be useful and successful provided that embryo transport, ET, and recipient conditions are adequate.

Preparation and Characterization of Holmium-Beta-Cyclodextrin Complex

The purpose of this study was to prepare and characterize of holmium-beta-cyclodextrin complex (Ho-β-CD) in order to increase the solubility and stability of Holmium. To achieve this goal, Ho-β-CD complex was prepared by evaporation method of holmium and beta cyclodextrin solutions in a proportion (1:1) and (1:3), respectively. Infrared (IR) and Raman spectroscopy, X-Ray Diffraction were performed to identify the complex. Morphology of the Ho, β-CD, and Ho-β-CD were studied using Scanning Electron Microscopy (SEM).

Pronuclear formation by ICSI using chemically activated ovine oocytes and zona pellucida bound sperm

Background： In order to improve ICSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICSI with chemically activated ovine oocytes and sperm selected by swim up（SU） or swim up ＋ zona pellucida（SU ＋ ZP） binding.Results： Experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation（precense of one PN）. Treatments showed similar results（54, 47, 42 %, respectively） but statistically differents（P 0.05）.Conclusions： Chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU ＋ ZP increased AR/A and AR/D rates in comparison with SU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after ICSI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with SU and SU ＋ ZP were significantly different than frozen-thawed sperm,but between sperm treatments no significant differences were obtained.