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El estudio del registro arqueobotánico asociado a un individuo femenino del sitio de Quilicura 1 permitió acercarnos a entender cómo los contextos funerarios del periodo Tardío (1400-1536 dC) contribuyen a la comprensión de los procesos sociopolíticos asociados a la presencia inka en la zona central de Chile. A través de los carporrestos y microrrestos de los residuos de uso de piezas cerámicas ofrendadas, se logró determinar el uso de plantas silvestres y domesticadas en la preparación de alimentos para los difuntos. Estas comidas y preparaciones tipo chicha, además de la presencia de un conjunto de artefactos vinculados a su preparación y consumo, habrían sido la esencia de la hospitalidad, una actividad fundamental en la integración eficiente de las poblaciones locales y, por ende, del funcionamiento del Tawantinsuyu.
Natural mortality (M) is a key parameter for understanding population dynamics, especially in relation to harvested populations. Direct observations of M in crustaceans are scarce, due to the moulting process. Indirect methods to estimate M with easier-to-obtain life history attributes are therefore used routinely. Given their theoretical background, we reviewed the applicability of these methods for crustaceans. We applied the selected methods to two crustacean species harvested in Chilean waters: the yellow squat lobster (Cervimunida johni) and red squat lobster (Pleuroncodes monodon). Uncertainty of each M estimate was incorporated in the life history parameters that input into the indirect method (trait-error) and parameters defining the indirect method (coefficient-trait-error). Methods based on the relationship between total mortality and maximum age, or with different ages and based on life history theory were the most appropriate for crustaceans since they apply across taxa. M estimates showed high variability between species, sexes and areas. Estimations of M for C. johni varied from 0.13 to 0.28 (year−1) for males and 0.17 to 0.51 (year−1) for females. For P. monodon values for the north varied from 0.26 to 0.37 (year−1) for males and 0.24 to 0.45 (year−1) for females. In the south, values of M were higher for both males (0.43–0.68 year−1) and females (0.41–1.06 year−1). High variability in the M estimates was associated with the method and number of parameters, their uncertainty, theoretical background and probability distribution. M estimates are not comparable, raising the need to propagate the uncertainty of M into the stock assessment of Chilean squat lobsters.
In small developing countries like Belize, lack of funding for archaeological research and post excavation curation remains one of our greatest challenges to preserving our tangible cultural heritage. The state of curation of human remains and artefact collections at St. John's College in Belize City is a perfect example of what can go wrong in the absence of a properly funded and managed curation program both at the national and the institutional level. This article highlights the rediscovery of a historically significant group of over 70 human remains in the biological collection of Friar Deickman, which had been forgotten in an attic after his death in 2003. We outline the process of, and accomplishments in improving the curation conditions of these individuals while uncovering their importance to Belizean history in the eighteenth through twentieth centuries. Preliminary analysis reveals life histories of slavery and indentured servitude of individuals of African, Maya, European, and possible mixed African and European descent. We emphasize the importance of ethical responsibility in properly curating excavated human remains, and the challenges researchers face when poor curation results in lost provenience. We offer suggestions for scientific analysis in recovering information lost as a result of poor excavation or curation methods.
In recent years, modified graphene has been used in various biomedical applications due to its excellent properties that allow the development of devices capable of detecting macromolecules within the human organism, also for biomolecular analysis, discovery of biomarkers, bioimaging and target delivery. These applications involve interactions between enzymes, proteins, peptides, DNA, RNA, etc. and modified graphene, therefore the study and the theoretical and experimental investigation of these interactions is essential for the development of nanobio-technology. For example, many applications based on using modified graphene to detect macromolecules require studying the changes in the properties of doped graphene when interacting with macromolecules. In this work, DFT and molecular dynamics methods were used to obtain results of the changes in energy density of states of graphene doped with iron when it is made to interact with coenzyme A. Besides, we presented a study of molecular dynamics in order to determine the quantum factors that guide the interaction graphene-coenzyme A. The system was studied in aqueous medium which it was simulated by the dielectric constant of water. The results confirm that the methodology presented in this work can be used to theoretically detect various macromolecules.
We present hydrodynamic and magnetohydrodynamic (MHD) simulations of liquid sodium flows in the von Kármán sodium (VKS) set-up. The counter-rotating impellers made of soft iron that were used in the successful 2006 experiment are represented by means of a pseudo-penalty method. Hydrodynamic simulations are performed at high kinetic Reynolds numbers using a large eddy simulation technique. The results compare well with the experimental data: the flow is laminar and steady or slightly fluctuating at small angular frequencies; small scales fill the bulk and a Kolmogorov-like spectrum is obtained at large angular frequencies. Near the tips of the blades the flow is expelled and takes the form of intense helical vortices. The equatorial shear layer acquires a wavy shape due to three coherent co-rotating radial vortices as observed in hydrodynamic experiments. MHD computations are performed: at fixed kinetic Reynolds number, increasing the magnetic permeability of the impellers reduces the critical magnetic Reynolds number for dynamo action; at fixed magnetic permeability, increasing the kinetic Reynolds number also decreases the dynamo threshold. Our results support the conjecture that the critical magnetic Reynolds number tends to a constant as the kinetic Reynolds number tends to infinity. The resulting dynamo is a mostly axisymmetric axial dipole with an azimuthal component concentrated near the impellers as observed in the VKS experiment. A speculative mechanism for dynamo action in the VKS experiment is proposed.
OBJECTIVES/SPECIFIC AIMS: Several clinical studies have established a correlation between changes in relative bacterial populations in the gut and Parkinson disease. However, few published experiments have been able to parse out whether these associations are causative or correlative. Our aim is to determine how bacteria in the gut may impact the health and resilience of dopaminergic signaling. Our experiment is designed to serve as a proof-of-principle that controlled alterations to the gut microbiome alters mechanisms in dopamine homeostasis in the midbrain. METHODS/STUDY POPULATION: Bacterial inoculation 8–10-week-old germ-free male mice (C57BL/6) were exclusively used in this experiment. Mice were orally gavaged every 3 days (D0, 3, 6, and 9) with 100 µL novel bacterial suspension (~108 CFU resuspended in PBS with 1.5% NaHCO3) or vehicle and were sacrificed on D11. Tissue preparation—brains were quickly extracted and the striatum was isolated and homogenized in either RIPA buffer with protease inhibitors (for Western blot analysis) or in 0.1 N HClO4 (for HPLC processing). The homogenates were processed through fractional centrifugation to remove cellular debris. Lysate samples were frozen at −80°C until ready for analysis. Protein expression quantification—expression of proteins were measured using intensity of bands from Western blots. Lysates were denatured prior to loading with LB with 10% β-mercaptoethanol and 30-minute incubation at 37°C. All immunoblots were normalized to immunoreactivity to α-tubulin. Immunoblot intensity was determined using the ImageJ software. Dopamine/dopamine metabolite quantification HPLC analysis was used to determine dopamine and dopamine metabolite concentration. Aliquots of the lysate were injected onto a C18 column using a mobile phase consisting of 50 mM H2NaO4P·H2O, 0.72 mM sodium octyl sulfate, 75 µM Na2 EDTA, and 10% acetonitrile (pH 3.0). The mobile phase was pumped through the system at 0.3 mL/minute. RESULTS/ANTICIPATED RESULTS: Measured total dopamine concentration through HPLC analysis in the striatum showed no significant differences in the bacteria-treated group relative to the control group. The metabolites DOPAC and HVA had an elevated measured concentration in the bacteria-treated group relative to the control group. Western blot analysis showed decreased immunoreactivity for DAT and TH in the bacteria-treated group compared with the control group. There was no significance difference in the immunoreactivity for VMAT2. DISCUSSION/SIGNIFICANCE OF IMPACT: This study demonstrates that dopamine signaling dynamics in the midbrain can be altered by changes in the gut flora in mice. These results further substantiate the impact of the gut-brain axis and may even point to a potential avenue of bolstering the resilience of dopaminergic neurons in preventing the onset of PD. Further experiments must be performed to understand the mechanism of the observed changes and to determine if these changes have any salutary effect.
In the present investigation, nanostructured ceramic HfN coatings were deposited onto silicon (100) wafer by magnetron sputtering DC method, from a metallic Hf target. The deposition process followed by a similar pattern as the multilayer film deposition, using cycles with the nitrogen gas turned on for 90 s and turned off for 15 s; four sets of samples were obtained using 5, 10, 15 and 20 cycles. The X ray diffraction (XRD) identified the presence of two different cubic crystalline phases of HfN, corroborated by Rietveld analysis. The Vickers hardness test showed that the hardness values increases with more cycles, due to a higher compressive stress evaluated by Stoney formula. All samples were investigated with no visible fracture until 10 grf for the 5 cycles sample; however, no fractures were visible at all for the 15 and 20 cycle samples for that given load, instead fractures started to appear at 25grf for the 10 and 15 cycles coating. Eventually it is distinguished that, the thickness and morphology of the coatings were measured by field emission scanning electron microscopy FE-SEM. As well as, the thickness increased from 0.4 µm to almost 1.33 µm as the number of cycles also increased, where we can observe the formation of columnar growth, moreover it is possible to distinguish the formation of two different clusters which might be related to different phases.
We have studied the structural and morphological properties on the pyrochlore (Er2-x Srx)Ru2O6 system, for x = 0.0, 0.02, 0.05, 0.07, 0.10, and 0.15. Polycrystalline samples were prepared by solid-state reaction (SR) and sol-gel acrylamide polymerization (SGAP). Thermogravimetric Analysis (TGA) was used to follow the thermal transformations such as reagents decomposition, phase transformation, chemical stability, and volatilization of organic material of samples. The reagents and synthesized products by the different methods of synthesis were characterized using powder X-ray diffraction (XRD). All samples crystallize Er2Ru2O6 PDF (72-7620) in the cubic unit cell with Fd
m (No. 227) space group and form a solid solution up to x = 0.15. Scanning electron microscopy (SEM) shows considerable variations and similitudes in sizes, very few phases and shapes of polycrystals can be observed. Polycrystalline samples prepared by solid-state reaction (SR) present a grain size varies between 77 nm to 250 nm.
This paper focus on evaluating the ability to use Mexican fly ash (FA) and copper slag (CS) to produce alkali cements (0% OPC) or hybrid cements (20% OPC + 80% fly ash). The alkali activators used were two: 8 M NaOH solution for alkali cements and NaCl with sodium silicate for hybrid cement (HYC). Results of mechanical testing and characterization of the reaction products formed after 2 and 28 days are presented and discussed. Mechanical strength in some cases exceeded 20 MPa, at 2 days curing. The chemical characterization techniques used were X-Ray Diffraction (XRD) and scanning electron microscopy (SEM).
Aluminum titanium oxynitride (TiAlNO) coatings were deposited on 316 steel substrates by the sputtering technique, varying the nitrogen flow from 2.5, 5, 7.5 to 10 sccm, and maintaining constant at 12 sccm the flow argon gas. We used targets of titanium and alumina with 99.995% purity. The hardness and tribological analyses were determined by Vickers microhardness and tribology (tribometer pin-disc), respectively. The results show that the coating with a nitrogen flow of 10 sccm had the lowest volumetric wear (2.047738693 mm3) and the maximum value of hardness (11.2 GPa). Analysis of X-ray diffraction evidenced the presence of three crystalline phases: Ti2N, Al2O3 and TiO2. It can be observed that by increasing the nitrogen flow, the portion of semi-Ti2N phase increases, Al2O3 decreases and TiO2 remains almost constant, and also producing a change in crystallographic orientation with reference to the Ti2N phase. Crystal grain sizes were estimated by X-ray diffraction Fourier line profile analysis using Warren–Averbach method. This analysis showed a grain size between 5 and 15 nm. Raman spectroscopy results show the presence of the TiO2 phase which corroborated the X-ray diffraction results.
Why do some leaders protect their citizens from natural disasters while others do not? This paper argues that leaders in large coalition systems provide more protection against natural disasters than leaders in small coalition systems. Yet, autocrats also provide large-scale disaster protection if members of their winning coalition are exposed to natural hazards. The paper tests these propositions by examining cross-country variation in the number of sea-level stations as a lower bound for protection against ocean-originated disasters. Empirical evidence indicates that leaders in large coalition systems deploy more sea-level stations than their counterparts in small coalition systems. The evidence also shows that if the national capital is close to the coast, thus exposing members of the ruling coalition to ocean-originated hazards, leaders across political systems install more sea-level stations.
Stratigraphy, geochemistry and radiocarbon dating of a succession of sediment in the Santiaguillo Basin (central-northern Mexico) help reconstruct the millennial-scale dynamics of hydrological variability that occurred in the southern part of western subtropical North America since the late last glacial. Runoff was generally above average during the late last glacial from ~ 27 to 18 ka. Following this interval, runoff decreased and deposition of authigenic carbonate and aeolian transported sediment increased until ~ 4 ka. Heinrich 1 and 2, and Younger Dryas were intervals of reduced runoff and increased aeolian activity. The wetter climate of central-northern Mexico and arid conditions in north–northwestern Mexico during the late last glacial were probably related to formation of tropical cyclones in the eastern North Pacific during the autumn with restricted rainfall swaths and an absent/weaker North American Monsoon. Enhanced North American Monsoon and tropical cyclones with expanded rainfall swaths brought more summer and autumn precipitation to a broader region extending from the central-northern Mexico to the continental interiors of southwestern US during the early Holocene.
Introduction. Polyphenols have received significant attention in
recent years due to their antioxidant capacity and their significant role in disease
prevention. Cocoa is one of the major naturally occurring sources of antioxidants,
particularly of polyphenolic compounds. Materials and methods. Gelatin
nanoparticles loaded with a cocoa-derived polyphenolic extract were synthesized by
nanoprecipitation. The nanoparticle synthesis was performed using a central composite
experimental design that allowed for the assessment of how gelatin concentration and
surfactant concentration (Tween 80) affected the hydrodynamic diameter and polydispersity
of the particles. The nanoparticles were characterized using dynamic light scattering
(DLS), assessments of zeta potential, scanning electron microscopy (SEM) and Fourier
transform infrared spectroscopy (FT-IR). Results. The analyses demonstrated
that the nanoparticles examined exhibited hydrodynamic diameters of (100 to 400) nm,
polydispersity indices of less than 0.2 and average zeta potential values of 29–33 mV. SEM
images revealed that most nanoparticles were spherical and uniform in morphology, with
average sizes less than 250 nm. In vitro experiments in which the
2,2-diphenyl-1-picrylhydrazyl (DPPH) method was used to assess the prevalence of free
radical-scavenging ability among these nanoparticles indicated that the loading efficiency
for the nanoparticles was approximately 77.56%. Conclusion. Nanoparticles
loaded with polyphenolic extract were obtained with average sizes ranging from (120 to
250) nm and largely spheroidal morphologies. Polymer and surfactant concentrations
significantly influenced the hydrodynamic diameters and polydispersity indices of the
particles. The incorporation of the polyphenolic extract into the polymer matrix enabled
the preservation of the antiradical activity of the bioactive compound.
Leucine aminopeptidase (LAP) and cathepsin L1 (CL1) are important enzymes for the pathogenesis and physiology of Fasciola hepatica. These enzymes were analysed in silico to design a chimeric protein containing the most antigenic sequences of LAP (GenBank; AAV59016.1; amino acids 192–281) and CL1 (GenBank CAC12806.1; amino acids 173–309). The cloned 681-bp chimeric fragment (rFhLAP-CL1) contains 270 bp from LAP and 411 bp from CL1, comprising three epitopes, DGRVVHLKY (amino acids 54–62) from LAP, VTGYYTVHSGSEVELKNLV (amino acids 119–137) and YQSQTCLPF (amino acids 161–169) from CL1. The ~25 kDa rFhLAP-CL1 chimeric protein was expressed from the pET15b plasmid in the Rosetta (DE3) Escherichia coli strain. The chimeric protein rFhLAP-CL1, which showed antigenic and immunogenic properties, was recognized in Western blot assays using F. hepatica-positive bovine sera, and induced strong, specific antibody responses following immunization in rabbits. The newly generated chimeric protein may be used as a diagnostic tool for detection of antibodies against F. hepatica in bovine sera and as an immunogen to induce protection against bovine fasciolosis.
The motility parameters of Fasciola hepatica miracidia were assessed at different temperatures and times post-hatching using computer-assisted sperm analysis. Eggs were incubated at 22°C or 25°C for 14 days. Five motion parameters were evaluated at different incubation temperatures up to 10 h post-hatching. No differences were observed in the percentage that hatched after incubation at the two different temperatures. However, the straight-line velocity of miracidia following incubation at 22°C was significantly different from that observed at 25°C (P< 0.01). All miracidium motion parameters at different post-hatching temperatures showed an overall decrease at the end of the experiment. Those miracidia hatching from eggs incubated at 25°C had a higher velocity of 1673.3 μm/s compared with 1553.3 μm/s at 22°C. Velocity parameters increased as the post-hatching temperature increased from 22°C to 37°C.
We investigated a basic generalization in parasite community ecology stating that stochastic processes played a major part in determining the composition of helminth communities of freshwater fish, or on the contrary, if these communities are predictable, diverse and structured species assemblages. We determined the species pool of helminth parasites of a tropical freshwater fish Heterandria bimaculata in its heartland, the upper Río La Antigua basin in east-central Mexico. Approaching our data from the metapopulation standpoint we studied the spatial patterns, and examined the variation in composition and richness of the component communities across different locations. We tested the prediction that helminth species may be recognized as common or rare; and also two hypotheses anticipating depauperate communities and decay of similarity between component communities with increasing distance. We found these communities composed by a highly structured and predictable set of specialist autogenic helminth species that are constant and abundant, dominating all components throughout space. The prediction that it is possible to recognize common and rare species was met. Richer than expected communities were found, as well as highly homogeneous component communities, where neighbouring components were more similar than distant ones. We speculated that the processes shaping the development of these component communities include stable, predictable habitats through time, allowing for a slow gradual dispersion process limited by host and parasite species capabilities. Our study suggests that metapopulation theory can assist in the prediction of community composition and in the understanding of spatial and temporal community variability.