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Copyright of Revista Científica Arbitrada Multidisciplinaria PENTACIENCIAS is the property of Revista Científica Arbitrada Multidisciplinaria PENTACIENCIAS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Enterolobium cyclocarpum and Piscidia piscipula are two important tree Fabaceae species distributed from the Yucatan Peninsula, Mexico. Our aims were focused on the E. cyclocarpum and P. piscipula seeds for: (1) to examine the seed permeability and imbibition rate, (2) to evaluate the effect of seed pre-germinative treatments, and (3) to characterize the structures involved on the presence of physical dormancy (PY). We used fresh seeds to determine seed permeability and imbibition rate, seed viability by means of tetrazolium test, furthermore, we applied mechanical scarification and boiler shocks for 5 s, 10 s and 15 s treatments. Morphological characterization of the seed coat was by Scanning Electron Microscope (SEM). Seed viability in E. cyclocarpum and P. piscipula were 100% and 96%, respectively. Seed permeability and imbibition rate in E. cyclocarpum were low. The highest germination in E. cyclocarpum was in the mechanical scarification (92%), while in P. piscipula, this parameter was in the 10 s boiling water treatment (76.0%). The presence of PY was confirmed in both species because they showed low seed permeability, and imbibition rate; furthermore, exhibited macrosclereids cells. The present research seeks to promote the sustainable use of E. cyclocarpum and P. piscipula. [ABSTRACT FROM AUTHOR]

This study deals with the characterization of exopolysaccharides (EPS) synthesized by a halophilic bacterium Salibacterium halochares STm recently isolated from saline soil in Cuatro Ciénegas Basin, Coahuila Mexico. S. halochares exhibited an EPS production of 17.38 g/L (at 72 h), using a modified ATCC 2185 culture medium (with yeast extract at 6 g/L and NaCl at 120 g/L). Chemical characterization of the EPS revealed a composition of total sugars, protein, and uronic acids contents of 83.83%, 1.59% and 2.09% (w/w), respectively. The purified EPS showed a molecular weight of 1283 kDa. Rheological studies of the EPS aqueous solutions indicated a non-Newtonian rheological behaviour which was reliably modeled by the Cross equation. The EPS showed high emulsification indexes (EI) against diverse non-polar substances and formed microemulsions with negative high ζ -potential values (up to − 46 mV). The viscoelastic behaviour data indicated the high stability of hexane–water (1:1 ratio) emulsions stabilized with EPS. The EPS retained its EI at harsh conditions of pH (4, 6.5, 7 and 12), NaCl (0, 2.0 and 4.0 M) and thermal incubation (up to 40 °C, 60 min). This is the first time that a Salibacterium genus member is reported as an EPS-producer. These results reveal the discovery of a novel polysaccharide with great potential for industrial applications, such as emulsion stabilizer, viscosity modifier and thickener. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Volcanology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Guayusa (Ilex guayusa) is an endemic plant from the Amazon with potential medicinal applications. Indigenous people are familiar with such applications and use guayusa based on ancestral knowledge. There is a growing interest in guayusa-based products in urban areas of Ecuador and internationally. The supply cannot meet the demand. Currently, traditional practices are used for guayusa growth and the potential use of the protected forest is foreseen. This work describes a protocol for the in vitro propagation of guayusa, a sustainable solution to generate high quality plants in reduced space. Stakes obtained from stems were used as explants. Chemical sterilization with ethanol and sodium hypochlorite resulted in 100% surface-sterilized stakes. The growth medium mWPM resulted in favorable outcomes regarding shoot development and elongation, as well as rooting. Supplementation with activated charcoal resulted in reduced browning, only 10% of the shoots presented necrosis during the elongation phase. More than two thirds of shoots were able to develop roots spontaneously. Medium supplementation with the auxin indole-3-butyric acid, IBA, may be considered when rooting does not occur spontaneously. Acclimatization was performed in soil. The protocol was tested under different light spectra, revealing that guayusa growth is affected by light quality. The photobiology of this shade tolerant plant requires further characterization, but the data uncovered a potential role for green and far-red light in root development. Key message: Guayusa was propagated on mWPM medium supplemented with activated charcoal. Spontaneous root development occurred in most shoots. Light quality affected plant development, green and far-red light could influence root growth. [ABSTRACT FROM AUTHOR]

We present evidence of volcano‐tectonic interactions at Sabancaya volcano that we relate to episodic magma injection and high regional fluid pore pressures. We present a surface deformation time series at Sabancaya including observations from ERS‐1/2, Envisat, Sentinel‐1, COSMO‐SkyMed, and TerraSAR‐X that spans June 1992 to February 2019. These data show deep‐seated inflation northwest of Sabancaya from 1992–1997 and 2013–2019, as well as creep and rupture on multiple faults. Afterslip on the Mojopampa fault following a 2013 MW 5.9 earthquake is anomalously long lived, continuing for at least 6 years. The best fit fault plane for the afterslip is right‐lateral motion on an EW striking fault at 1 km depth. We also model surface deformation from two 2017 earthquakes (MW 4.4 and MW 5.2) on unnamed faults, for which the best fit models are NW striking normal faults at 1–2 km depth. Our best fit model for a magmatic inflation source (13 km depth, volume change of 0.04 to 0.05 km3 yr−1) induces positive Coulomb static stress changes on these modeled fault planes. Comparing these deformation results with evidence from satellite thermal and degassing data, field observations, and seismic records, we interpret strong pre‐eruptive seismicity at Sabancaya as a consequence of magmatic intrusions destabilizing tectonic faults critically stressed by regionally high fluid pressures. High fluid pressure likely also promotes fault creep driven by static stress transfer from the inflation source. We speculate that combining high pore fluid pressures with sufficiently large, offset magmatic inflation can promote strong earthquakes during volcanic unrest. Key Points: InSAR analysis provides evidence for laterally and vertically complex volcanic plumbing system at SabancayaHigh fluid pressure at Sabancaya promotes strong seismicity during 2012–2019 eruptive periodHigh fluid pressure and static stress transfer from deep inflation promote long‐lived fault creep [ABSTRACT FROM AUTHOR]

Surface‐Active Biomolecules (SAB) obtained from microbial sources are safe alternatives to chemically synthesized counterparts for many environmental and industrial applications. These applications frequently involve the exposure of the SAB to extreme factors making necessary to seek for molecules that are able to function under such conditions. In this work, the polyextremophilic bacterium Salibacterium sp. 4CTb is reported as a SAB producer. Its emulsifier activity increased almost twofold when the C/N ratio and culture conditions were modified. The partially purified molecule was able to form stable emulsions under extreme conditions (70 °C, pH 12, and 4 M NaCl) better than other commercial molecules, and reduced the surface tension of the water to 49.78 mN m−1 with critical micelle concentration (CMC) of 15.1 mg L−1. Carbohydrate, lipid, and protein assays, accompanied by the Fourier Transform Infra‐Red (FTIR) and electrospray ionization mass spectroscopy (ESI‐MS) results, indicate the lipopeptide nature of the compound with masses around 645 and 746 Da. The SAB obtained from Salibacterium sp. 4CTb may be suitable for electrical, food, pharmaceutical and cosmetic industries, agriculture, and environmental applications, among others. [ABSTRACT FROM AUTHOR]

Mining is known as one of the primary economic activities where exploitation of minerals and other materials have become essential for human development. However, this activity may represent a risk to the environment, starting from deforestation and ending with production of residues that might contain potentially toxic elements. Tailing deposits from historical mining are an example of waste that may represent an environmental concern when abandoned and exposed to environmental conditions. The town of Nacozari de Garcia, in northwestern Mexico, has three abandoned mine tailings (locally known as tailings I, II, and III) located around the urban area that represent important sources of dust and pollution. Images obtained using unmanned aerial vehicles (UAV) in conjunction with geochemical data are used to assess historic erosion calculation and pollution considering contamination and hazard indexes in tailings II and III. Digital elevation models of abandoned tailings were obtained using photogrammetry with UAV. A total of 37 surficial samples were collected from mine tailings to determine elemental concentrations (As, Cu, Pb, W, Zn) using portable X-ray fluorescence. Higher concentrations were found on samples from mine tailing II. Average concentrations followed the decreasing order of Cu > Zn > W > Pb > As for tailing II, whereas decreasing order of Cu > Zn > W > As > Pb was found for tailing III. Contamination Index (CI) values obtained from tailings II and III represent a low potential of pollution, whereas efflorescent crusts from these tailings represent a high potential of polluting soils and sediments by dust generation. Hazard Average Quotient (HAQ) values on both tailings suggest a very high potential of contamination if fluids infiltrate tailings and interact with surficial water and/or groundwater. Obtained surfaces of mine tailings II and III are 146,216 and 216,689 m2, respectively, which represent around 11% of the urbanized area. A loss mass of 321,675 tons was determined for mine tailing II, whereas 634,062 tons for tailing III, accounting for 0.96 million tons of total eroded mass. Since abandonment, calculated erosion rates of 493 t ha−1 year−1 (tailing II) and 232 t ha−1 year−1 (tailing III) are in agreement with those determined in other mining areas. CI and HAQ indexes provide good estimates of pollution associated with abandoned mine tailings from Nacozari de García. Historic erosion determined in these tailings is an environmental concern since eroded material and polluted water have been incorporated into the Moctezuma River, which feeds several villages, whose major activities include agriculture and livestock raising. [ABSTRACT FROM AUTHOR]

Background: Artificial Mitochondrial Transfer or Transplant (AMT/T) can be used to reduce the stress and loss of viability of damaged cells. In MitoCeption, a type of AMT/T, the isolated mitochondria and recipient cells are centrifuged together at 4 °C and then co-incubated at 37 °C in normal culture conditions, inducing the transfer. Ultraviolet radiation (UVR) can affect mitochondria and other cell structures, resulting in tissue stress, aging, and immunosuppression. AMT/T could be used to repair UVR cellular and mitochondrial damage. We studied if a mitochondrial mix from different donors (Primary Allogeneic Mitochondrial Mix, PAMM) can repair UVR damage and promote cell survival. Results: Using a simplified adaption of the MitoCeption protocol, we used peripheral blood mononuclear cells (PBMCs) as the recipient cell model of the PAMM in order to determine if this protocol could repair UVR damage. Our results showed that when PBMCs are exposed to UVR, there is a decrease in metabolic activity, mitochondrial mass, and mtDNA sequence stability as well as an increase in p53 expression and the percentage of dead cells. When PAMM MitoCeption was used on UVR-damaged cells, it successfully transferred mitochondria from different donors to distinct PBMCs populations and repaired the observed UVR damage. Conclusion: Our results represent an advancement in the applications of MitoCeption and other AMT/T. We showed that PBMCs could be used as a PAMM source of mitochondria. We also showed that these mitochondria can be transferred in a mix from different donors (PAMM) to UVR-damaged, non-adherent primary cells. Additionally, we decreased the duration of the MitoCeption protocol. [ABSTRACT FROM AUTHOR]

Copyright of Revista Biomedica is the property of Centro de Investigaciones Regionales Dr. Hideyo Noguchi; Facultad de Medicina, UADY and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the most important Mayan cities of the Classic period (A.D. 200-900) of Mesoamerica is Palenque, in Chiapas. The Mayan civilization attributed great importance to greenstone minerals, in particular jadeite. This study covers the analysis of greenstones found in royal tombs of several temples corresponding to the Classic period: the Temple of the Skull, Temple of the Cross and Temples XVIII and XVIII-A. The aim of this research is to determine the use of greenstone minerals and the raw materials' sources as a first step in understanding the development of Palenque and its relationships to other sites in the Maya region. Here, we present a non-destructive in situ study of lithic objects carried out by means of a several spectroscopic techniques, such as Raman, Fourier transform infrared (FTIR), X-ray fluorescence (XRF) and color measurements, at the Palenque site museum. FTIR and Raman allowed for the identification of minerals including jadeite, omphacite, amazonite, albite, muscovite and green quartz. Moreover, XRF was effective for in situ analysis of the elemental composition of the artifacts. This information was essential for sourcing the raw materials, in particular, jadeite. It was possible to infer the exploitation of an unknown source of jadeite for the earlier burial (A.D. 250-450). During this period the exploitation of the Verapaz and Motagua jadeite deposits also began. These sources were the primary deposits used for the manufacture of the artifacts studied from the period of A.D. 600-850. Also, a greater diversity of minerals is observed during the zenith of Palenque during this period, corresponding to the reign of Pakal. Although, between burials, the color of the artifacts is diverse, the color measurements indicated similarity in color among artifacts within individual burials. [ABSTRACT FROM AUTHOR]

Background: Increasing dialysate flow rates (Qd) from 500 to 800 ml/min has been recommended to increase dialysis efficiency. A few publications show that increasing Qd no longer led to an increase in mass transfer area coefficient (KoA) or Kt/V measurement. Our objectives were: 1) Studying the effect in Kt of using a Qd of 400, 500, 700 ml/min and autoflow (AF) with different modern dialysers. 2) Comparing the effect on Kt of water consumption vs. dialysis time to obtain an individual objective of Kt (Ktobj) adjusted to body surface. Methods: This is a prospective single-centre study with crossover design. Thirty-one patients were studied and six sessions with each Qd were performed. HD parameters were acquired directly from the monitor display: effective blood flow rate (Qbe), Qd, effective dialysis time (Te) and measured by conductivity monitoring, final Kt. Results: We studied a total of 637 sessions: 178 with 500 ml/min, 173 with 700 ml/min, 160 with AF and 126 with 400 ml/min. Kt rose a 4% comparing 400 with 500 ml/min, and 3% comparing 500 with 700 ml/min. Ktobj was reached in 82.4, 88.2, 88.2 and 94.1% of patients with 400, AF, 500 and 700 ml/min, respectively. We did not find statistical differences between dialysers. The difference between programmed time and Te was 8′ when Qd was 400 and 500 ml/min and 8.8′ with Qd = 700 ml/min. Calculating an average time loss of eight minutes/session, we can say that a patient loses 24′ weekly, 312′ monthly and 62.4 hours yearly. Identical Kt could be obtained with Qd of 400 and 500 ml/min, increasing dialysis time 9.1′ and saving 20% of dialysate. Conclusions: Our data suggest that increasing Qd over 400 ml/min for these dialysers offers a limited benefit. Increasing time is a better alternative with demonstrated benefits to the patient and also less water consumption. [ABSTRACT FROM AUTHOR]