Rapid development in Yucatan has had a dramatic impact on the environment, especially the water supply. Groundwater is the only source of water in Yucatan, since surface water is virtually absent due ...to the karstic nature of the soil. The ring of cenotes (RC) is a geological feature which functions as a source of water and as nodes in the underground river system that canalizes water towards the coast. Numerous productive and domestic activities take place around the RC in the absence of wastewater treatment or sewage systems. Consequently, a number of researchers have hypothesized that pollutants could migrate from the land surface to the underlying aquifer and, eventually, to the coast. Therefore, the present study investigates the relationship among sources of fecal sterols and their levels in cenotes, using the expected levels of fecal sterols obtained by a spatial analysis of the sources and a Pollution Source Index. Accordingly, expected levels are compared with the detected levels of fecal sterols in 5 areas around the RC. Regarding levels, observed during a sampling campaign carried out along the RC during September 2011 (rainy season) and May 2012 (dry season), varied from low to high concentrations of sterols (0.5–2396.42μgg−1) and fecal sterols (0.3–1690.18μgg−1). These concentrations showed no relationship between neighboring cenotes, where similar fecal sterol concentrations or gradients were expected. When comparing expected fecal sterols levels with the detected ones, only two of the five analyzed areas concur, suggesting that no clear relationship exists among sources and fecal sterols levels at the regional scale. Multivariate analysis showed that fecal sterols were associated with sterols and fine grain particulates during the rainy season, which suggests co-transport. During the dry season, fecal sterols associated with fine grain particulate and organic matter, which indicates a change to a deposition phenomenon. These findings indicate that defining a relationship among sources and fecal sterols levels is highly difficult and this could be the result of the absorption or migration through an intricate conduit, crack, or fracture karst system. Nevertheless, the “source-levels approach”, used in this study, was consistent for the northeast edge and the middle western part of the RC. New and more extensive research should be done to assess the environmental fate of fecal sterols, especially considering the intricate karstic system and its compound retention capacity.
•The highest fecal sterols (FS) levels were found on the NE coast of Yucatan.•FS show seasonally dependent presence in the sinkholes of the ring of cenotes.•Multivariate analyses show FS transport/deposition with fine grain/organic matter.•The Pollution Source Index showed no clear relationship among sources and FS levels.•Migration through the karst system could promote absorption of FS to bedrock.
A bone's fracture could be produced by an excessive, repetitive, or sudden load. A regular medical practice to heal it is to fix it in two possible ways: external immobilization, using a ferule, or ...an internal fixation, using a prosthetic device commonly attached to the bone by means of surgical screws. The bone's volume loss due to this drilling modifies its structure either in the presence or absence of a fracture. To observe the bone's surface behavior caused by the drilling effects, a digital holographic interferometer is used to analyze the displacement surface's variations in nonfractured post-mortem porcine femoral bones. Several nondrilled post-mortem bones are compressed and compared to a set of post-mortem bones with a different number of cortical drillings. During each compression test, a series of digital interferometric holograms were recorded using a high-speed CMOS camera. The results are presented as pseudo 3D mesh displacement maps for comparisons in the physiological range of load (30 and 50 lbs) and beyond (100, 200, and 400 lbs). The high resolution of the optical phase gives a better understanding about the bone's microstructural modifications. Finally, a relationship between compression load and bone volume loss due to the drilling was observed. The results prove that digital holographic interferometry is a viable technique to study the conditions that avoid the surgical screw from loosening in medical procedures of this kind.
Lung cancer is the most common cause of cancer death in the United States. The genome of non-small cell lung cancer (NSCLC), the most frequent lung cancer type, is strongly affected by Long ...Interspersed Nuclear Element (LINE1) insertions. Active LINE1s are repetitive DNA sequences that can amplify themselves in the genome utilizing a retrotransposition mechanism whereby LINE1 is copied via reverse transcription and inserted at target sites. ORF1p and ORF2p are LINE1 encoded proteins essential for LINE1 retrotransposition. LINE1s are silenced epigenetically in somatic tissues, and their reactivation has been associated with cancer pathogenesis. Here, we present evidence that nucleolin (NCL) regulates expression of LINE1-ORF1p (L1-ORF1p) in NSCLC cells. Genetic knockdown of NCL significantly inhibited expression of L1-ORF1p in various NSCLC cell lines. Treatment with the investigational NCL antagonist N6L ablated L1-ORF1p expression in all cell lines constitutively expressing L1-ORFp. N6L displayed a stronger antiproliferative activity in NSCLC tumor cell lines expressing the highest L1-ORF1p protein levels. Moreover, N6L treatment of nude mice bearing NSCLC tumor xenografts blocked L1-ORF1p expression and effectively inhibited tumor growth
These data indicate that L1-ORF1p expression is regulated by NCL and identify NCL as a novel promising target for pharmacological inhibition of LINE1.
Polyurethanes (PU) are the sixth most produced plastics with around 18-million tons in 2016, but since they are not recyclable, they are burned or landfilled, generating damage to human health and ...ecosystems. To elucidate the mechanisms that landfill microbial communities perform to attack recalcitrant PU plastics, we studied the degradative activity of a mixed microbial culture, selected from a municipal landfill by its capability to grow in a water PU dispersion (WPUD) as the only carbon source, as a model for the BP8 landfill microbial community. The WPUD contains a polyether-polyurethane-acrylate (PE-PU-A) copolymer and xenobiotic additives (
-methylpyrrolidone, isopropanol and glycol ethers). To identify the changes that the BP8 microbial community culture generates to the WPUD additives and copolymer, we performed chemical and physical analyses of the biodegradation process during 25 days of cultivation. These analyses included Nuclear magnetic resonance, Fourier transform infrared spectroscopy, Thermogravimetry, Differential scanning calorimetry, Gel permeation chromatography, and Gas chromatography coupled to mass spectrometry techniques. Moreover, for revealing the BP8 community structure and its genetically encoded potential biodegradative capability we also performed a proximity ligation-based metagenomic analysis. The additives present in the WPUD were consumed early whereas the copolymer was cleaved throughout the 25-days of incubation. The analysis of the biodegradation process and the identified biodegradation products showed that BP8 cleaves esters, C-C, and the recalcitrant aromatic urethanes and ether groups by hydrolytic and oxidative mechanisms, both in the soft and the hard segments of the copolymer. The proximity ligation-based metagenomic analysis allowed the reconstruction of five genomes, three of them from novel species. In the metagenome, genes encoding known enzymes, and putative enzymes and metabolic pathways accounting for the biodegradative activity of the BP8 community over the additives and PE-PU-A copolymer were identified. This is the first study revealing the genetically encoded potential biodegradative capability of a microbial community selected from a landfill, that thrives within a WPUD system and shows potential for bioremediation of polyurethane- and xenobiotic additives-contamitated sites.
Pure K
0.5
Na
0.5
NbO
3
(KNN) and KNN doped with Li
+
(6% mole), La
3+
(1.66%, 5%, 6% mole), and Ti
4+
(10% mole) were prepared by mixture of oxides using high-energy milling and conventional ...solid-state reaction. The effects of the dopant on the physical properties of pure KNN have been evaluated based on the structural, ferroelectric, pyroelectric, and dielectric measurements. The XRD measurements show that KNN pure sample contains a mixture of monoclinic and orthorhombic crystalline phases, with a slightly higher concentration of monoclinic phase. In contrast, all doped samples show a higher concentration of the orthorhombic phase, as well as the presence of a secondary phase (K
6
Nb
10.8
O
30
), also detected by Raman measurements. The samples with a higher concentration of this secondary phase, also present greater dielectric losses and lower values of remnant polarization. The dielectric measurements allowed us to detect temperatures of structural transitions (orthorhombic-tetragonal, O-T) previous to the ferroelectric-paraelectric transition (tetragonal-cubic, T-C), and also in this set of samples, a direct correlation was found between the values of remnant polarization and the corresponding pyroelectric signal response.
La Enfermedad de Legg-Calvé-Perthes (ELCP) es una enfermedad rara, por su baja incidencia (0.2 a 19.9 casos por 100,000 habitantes) y etiología desconocida. Es una osteonecrosis avascular provocada ...por alteraciones en la circulación, con interrupción efectiva en el suministro de sangre, uni o bilateral, en la cabeza femoral; con colapso epifisario, deformidad, riesgo de coxartrosis temprana y limitación en el rango de movimiento de la cadera. Afecta a niños de 4-10 años (4/1 niños/niñas) que refieren dolor en la extremidad afectada, durante y después de la actividad física, así como marcha claudicante. Es bien aceptado por múltiples estudios que factores genéticos, metabólicos y ambientales podrían influir en el padecimiento de la ELCP, entre ellos disturbios en la hemostasia y la inflamación parecen tener un papel central en la etiología. el objetivo de este estudio es buscar la presencia de factores genéticos y metabólicos presentes en una población de pacientes sufren de ELCP, para esto fueron estudiados diferentes marcadores hemostáticos y diferentes polimorfismos relacionados a la ELCP y/o Osteonecrosis de la cabeza femoral. Fueron reclutados un total de 23 pacientes y 46 controles sanos pareados por sexo edad talla y peso, el grupo de pacientes incluyo un total de 21 varones y solo 2 mujeres y 3 casos bilaterales. Se presentaron diferencias significativas entre grupos en la actividad del FV (P<0.05), FIX (P<0.05) y concentración de Homocisteína (P<0.05), así como en los datos crudos del polimorfismo FIX Malmo (P<0.05), además la tendencia a aumentar el riesgo de padecer ELCP al ser portador de alguna o algunas variantes genéticas relacionadas a la inflamación, nuestro resultados muestran que la presencia de la mutación del FIX Malmo, así como variaciones génicas proinflamatorias podría influir en la presencia de la ELCP, tomados en conjunto estos datos apoyan las teorías en donde se proponen a factores genéticos y metabólicos como probables agentes etiológicos, por lo cual proponemos a la hemostasia e inflamación como posibles blancos terapéuticos en la ELCP.
With the aim to model the propagation of sound pressure emitted by a source, based on the postulates of Far from equilibrium thermodynamics theory, a wave equation was constructed. The equation ...obtained is a classic generalized wave equation adding dissipative behavior as a function of the media in which wave propagates. The new equation is of Maxwell-Cattaneo-Vernotte type. Also, an experimental activity was realized and the results were in accordance with theoretical solution of the new differential equation.
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•Stable isotopes of oxygen and hydrogen determined the recharge system of the Puebla aquifer.•No relationship between water types and radiometric dates.•Boron in groundwater was ...derived from geothermal activity and evaporites dissolution.
The geochemical evolution of groundwater of the Puebla aquifer was investigated using chemistry and isotopic data with special emphasis on the geochemistry of Boron to decipher the natural and anthropogenic sources. This study measured 70 groundwater samples that are potentially impacted by the urban and rural anthropic, volcanic and glaciation activities. Based on the distribution of anions and cations water samples were classified into three groups using Piper Diagram. Group1 showed to have high HCO3 than SO4, Group 3 high SO4 than HCO3 and Group 2 revealed intermediate composition. Radiometric studies show the presence of Pleistocene groundwater; however, there was no definite relationship between the radiometric dates to the groups except that enrichment in δD and δ13C values were noted with respect to age. Average Boron concentrations in some wells were observed to be higher (>5000 μg/L) than that of the permissible limit for human consumption. Results also indicated that the sources of Boron were more natural than anthropogenic that comprised the local geological conditions, volcanic activity and hydrothermal processes. The study also validated that the groundwater wells from the southwestern part of the study area are suitable for extraction of groundwater, considering its quality and residence time; whereas, in the wells located in the central-eastern zone of the metropolitan area, it is recommended that groundwater exploitation must be gradually reduced.
Yellow rust (YR) or stripe rust, caused by
Puccinia striformis
f. sp
tritici
Eriks (
Pst
), is a major challenge to resistance breeding in wheat. A genome wide association study (GWAS) was performed ...using 22,415 single nucleotide polymorphism (SNP) markers and 591 haplotypes to identify genomic regions associated with resistance to YR in a subset panel of 419 pre-breeding lines (PBLs) developed at International Center for Maize and Wheat Improvement (CIMMYT). The 419 PBLs were derived from an initial set of 984 PBLs generated by a three-way crossing scheme (exotic/elite1//elite2) among 25 best elites and 244 exotics (synthetics, landraces) from CIMMYT’s germplasm bank. For the study, 419 PBLs were characterized with 22,415 high-quality DArTseq-SNPs and phenotyped for severity of YR disease at five locations in Mexico. A population structure was evident in the panel with three distinct subpopulations, and a genome-wide linkage disequilibrium (LD) decay of 2.5 cM was obtained. Across all five locations, 14 SNPs and 7 haplotype blocks were significantly (
P
< 0.001) associated with the disease severity explaining 6.0 to 14.1% and 7.9 to 19.9% of variation, respectively. Based on average LD decay of 2.5 cM, identified 14 SNP–trait associations were delimited to seven quantitative trait loci in total. Seven SNPs were part of the two haplotype blocks on chromosome 2A identified in haplotypes-based GWAS.
In silico
analysis of the identified SNPs showed hits with interesting candidate genes, which are related to pathogenic process or known to regulate induction of genes related to pathogenesis such as those coding for glunolactone oxidase, quinate O-hydroxycinnamoyl transferase, or two-component histidine kinase. The two-component histidine kinase, for example, acts as a sensor in the perception of phytohormones ethylene and cytokinin. Ethylene plays a very important role in regulation of multiple metabolic processes of plants, including induction of defense mechanisms mediated by jasmonate. The SNPs linked to the promising genes identified in the study can be used for marker-assisted selection.
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