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In the last decade, the highest levels of greenhouse gases (GHG) in the atmosphere have been recorded, with carbon dioxide (CO2) being one of the GHGs that most concerns mankind due to the rate at which it is generated on the planet. Given its long time of permanence in the atmosphere (between 100 to 150 years); this has deployed research in the scientific field focused on the absorption and desorption of CO2 in the atmosphere. This work presents the study of CO2 adsorption employing materials based on graphene oxide (GO), such as GO foams with different oxidation percentages (3.00%, 5.25%, and 9.00%) in their structure, obtained via an environmentally friendly method. The characterization of CO2 adsorption was carried out in a closed system, within which were placed the GO foams and other CO2 adsorbent materials (zeolite and silica gel). Through a controlled chemical reaction, production of CO2 was conducted to obtain CO2 concentration curves inside the system and calculate from these the efficiency, obtained between 86.28 and 92.20%, yield between 60.10 and 99.50%, and effectiveness of CO2 adsorption of the materials under study. The results obtained suggest that GO foams are a promising material for carbon capture and the future development of a new clean technology, given their highest CO2 adsorption efficiency and yield. [ABSTRACT FROM AUTHOR]

Potassium (K), magnesium (Mg), calcium (Ca) and sulfur (S) are necessary for coffee production. To supply coffee requirements, approximately 50% of Colombian coffee growers use bulk blends of fertilizers. However, the fertilizer sources available are few and are usually not compatible with other granulated sources, causing low fertilization efficiency. To evaluate the effect of granulated polyhalite (GPoly4), a multimineral source of K, Mg, Ca and S, on coffee yield and coffee quality, an experiment was carried out on Colombian coffee growing in the experimental soil Typic Melanudand, containing 0.40, 0.50 and 0.40 cmol(P+) kg−1 of K, Ca, and Mg, respectively. The response of six treatments viz. NPK-GPoly4, NPK-CaNO3- CaSO4-MgO, NPK-MgSO4, NPK-CaNO3-MgSO4, NPK-CaNO3-MgO, and NPK (control), on yield and coffee quality were studied. Applications of NPK-GPoly4 and its nutritional equivalent, using NPK-CaNO3-MgO, increased coffee cherry yield. The nutrient content in coffee leaves and soil explained the results. The coffee bean had good quality, and the quality parameters of the coffee drink i.e. acidity, body and balance were much improved than the desired levels in all of the treatments. According to the results, GPoly4 must be considered as an alternate source to supply K, Ca, Mg and S to coffee in Colombia. [ABSTRACT FROM AUTHOR]

Reviewing a century of history, the development of anatomical activities in the city of Concepción, in the south of Chile, did not occur without difficulties. The present work gathered the historical background related with the beginnings and development of Anatomy teaching at the Universidad de Concepcion. Research was carried out including the review of historical books, magazines, digital archives and institutional records such as files or photographic archives. The foundation of the university, the beginnings of anatomical activities in 1919 and the contribution of its highlighted pioneers, show the difficulties of teaching this discipline in Chile. From a historical perspective, having knowledge during this century of teaching, the physical resources used in cadaveric dissection, the detail of teaching methodologies applied, and the anatomical resources available, contribute the anatomy´s development knowledge in Chile. [ABSTRACT FROM AUTHOR]

The constitutionalization of alternative forms of dispute resolution (ADR) is a mistake. It entails the risk of fossilizing tools that require, by way of their nature, a level of flexibility, and of hindering the possibility of having dispute resolution alternatives that respond to the needs of time. The constituents of 1991 decided to include within Article 116 of the Constitution specific considerations in reference to jurisdictional functions carried out by conciliators and arbitrators, a choice that has restricted and will continue to limiter these and other ADR mechanisms in a way detrimental to the entire dispute settlement system of Colombia. This article analyzes the precedents and discusses the mistakes inherent to the constitutionalization of an alternative form of dispute resolution as arbitration, and consequently also serves as a beckoning call for the Congress of Colombia --entity that is about to decide over a lengthy constitutional reform of the justice system-- not to perpetuate the mistakes of the drafters of the 1991 Constitution, and remove once and for all the incorrectly constitutionalized elements of ADR mechanisms. [ABSTRACT FROM AUTHOR]

Colombia continues to debate the implementation of electronic vote showing that there are fears in system access and data transfer, this research seeks to minimize vulnerability to cyber attacks by means of a prototype for the analysis of attacks and security of information sent during the giving confidence vote in the transmission, besides verifying voter physical access by biometrics, the tool uses the SSL / TLS protocols for authentication of the voter and the IPSEC protocol to validate the site, data and secure communications of unauthorized transactions. This system proposes the first integrated transportation lock and polling data access model, ensuring reliability voters; SSL / TLS protocols supplemented with IPSEC and new electronic systems for transmission validation of voters in polling stations benefit national democracy supported by new technologies. [ABSTRACT FROM AUTHOR]

Mutations of the PARK2 and PINK1 genes, encoding the cytosolic E3 ubiquitin-protein ligase Parkin and the mitochondrial serine/threonine kinase PINK1, respectively, cause autosomal recessive early-onset Parkinson's disease (PD). Parkin and PINK1 cooperate in a biochemical mitochondrial quality control pathway regulating mitochondrial morphology, dynamics and clearance. This study identifies the multifunctional PD-related mitochondrial matrix enzyme 17-β hydroxysteroid dehydrogenase type 10 (HSD17B10) as a new Parkin substrate. Parkin overproduction in cells increased mitochondrial HSD17B10 abundance by a mechanism involving ubiquitin chain extension, whereas PARK2 downregulation or deficiency caused mitochondrial HSD17B10 depletion in cells and mice. HSD17B10 levels were also found to be low in the brains of PD patients with PARK2 mutations. Confocal and Förster resonance energy transfer (FRET) microscopy revealed that HSD17B10 recruited Parkin to the translocase of the outer membrane (TOM), close to PINK1, both in functional mitochondria and after the collapse of mitochondrial membrane potential (ΔΨm). PD-causing PARK2 mutations impaired interaction with HSD17B10 and the HSD17B10-dependent mitochondrial translocation of Parkin. HSD17B10 overproduction promoted mitochondrial elongation and mitigated CCCP-induced mitochondrial degradation independently of enzymatic activity. These effects were abolished by overproduction of the fission-promiting dynamin-related protein 1 (Drp1). By contrast, siRNA-mediated HSD17B10 silencing enhanced mitochondrial fission and mitophagy. These findings suggest that the maintenance of appropriate mitochondrial HSD17B10 levels is one of the mechanisms by which Parkin preserves mitochondrial quality. The loss of this protective mechanism may contribute to mitochondrial dysfunction and neuronal degeneration in autosomal recessive PD. [ABSTRACT FROM AUTHOR]

The potential protective effect of the dietary antioxidant curcumin (120 mg/Kg/day for 6 days) against the renal injury induced by maleate was evaluated. Tubular proteinuria and oxidative stress were induced by a single injection of maleate (400 mg/kg) in rats. Maleate-induced renal injury included increase in renal vascular resistance and in the urinary excretion of total protein, glucose, sodium, neutrophil gelatinase-associated lipocalin (NGAL) and N-acetyl β-D-glucosaminidase (NAG), upregulation of kidney injury molecule (KIM)-1, decrease in renal blood flow and claudin-2 expression besides of necrosis and apoptosis of tubular cells on 24 h. Oxidative stress was determined by measuring the oxidation of lipids and proteins and diminution in renal Nrf2 levels. Studies were also conducted in renal epithelial LLC-PK1 cells and in mitochondria isolated from kidneys of all the experimental groups. Maleate induced cell damage and reactive oxygen species (ROS) production in LLC-PK1 cells in culture. In addition, maleate treatment reduced oxygen consumption in ADP-stimulated mitochondria and diminished respiratory control index when using malate/glutamate as substrate. The activities of both complex I and aconitase were also diminished. All the above-described alterations were prevented by curcumin. It is concluded that curcumin is able to attenuate in vivo maleate-induced nephropathy and in vitro cell damage. The in vivo protection was associated to the prevention of oxidative stress and preservation of mitochondrial oxygen consumption and activity of respiratory complex I, and the in vitro protection was associated to the prevention of ROS production. [ABSTRACT FROM AUTHOR]

Abstract: A comparison of the metabolic potential of 20 bioleaching microorganisms and their close relatives from the Eubacteria and Archaea kingdoms permits the prediction of inter- and intra-species physiological interactions (ecophysiology) during spatial and temporal changes that are known to occur within industrial bioleaching heaps. Genome analysis has allowed preliminary models to be built for genes and pathways involved in key processes such as nitrogen and carbon cycling, sulfur and iron uptake and homeostasis, extra-cellular polysaccharide biosynthesis, heavy metal resistance and energy metabolism. This paper will focus on the diverse ways that bioleaching microorganisms obtain carbon from their environment with a particular emphasis on elucidating how these processes might be expected to vary over space and time during the lifetime of a bioleaching operation. It is anticipated that this knowledge will improve our understanding of fundamental biological processes in extremely acidic environments. [ABSTRACT FROM AUTHOR]

Block and panel caving is one of the most suitable methods for exploitation of large massive ore bodies where a high rate of extraction is required. However, many authors have studied the rate of extraction and concluded that it may be limited by the ability to prepare mines at high rates. Different approaches, to increasing the rate of extraction, tend towards the introduction of some kind of continuous drawing and materials handling on production levels, which apparently are close to reaching a practical solution. However, corresponding studies to match the rate of mine preparation to high extraction rate operations have not been discussed or published to any great depth. This paper describes some layouts and constructive techniques compatible with rapid mine preparation demand. A significant reduction of time in mine preparation, in both underground drifting and construction, is expected as a consequence of the introduction of non-blasting excavation methods and using precast concrete modules to build up underground mine construction. The main advantage of non-blasting drifting is the predictability of finishing underground drifts, such that it is possible to standardise all the components of single underground mine constructions (i.e. drawpoint and dump points). The solution requires adapting and developing both new equipment and new layouts, because neither standard full face boring machines nor current layouts for conventional block/panel caving are suitable to high speed development of caving levels. The layouts discussed focus on conventional load-haul-dump units and on mechanised continuous drawing system arrangements. In each case, the general arrangement presented has been developed by JRI Ingeniería S.A. as part of its technological innovation policy. Finally, an evaluation of the impact upon scheduling and costs is presented in comparison with conventional methods. New approaches are also mentioned about other issues such as logistics and commissioning, with new actors in the business, which may produce additional benefits for project and operation management. [ABSTRACT FROM AUTHOR]

The human Chorionic Gonadotropin (hCG) by its effect similar to the one of LH, was used to improve the percentage of conception in mares, using frozen semen in the artificial insemination. For this, 20 mares cycling of natural way, belonging to the breed Cuato de Milla (Quarter Horse), in their reproductive age (6 to 12 years of age), were selected in a farm located in Mexico D.F. The animals were divided into 2 groups: Group 1; mares treated with 2000 UI hCG when presented Graff follicle equal or higher than 35 mm and inseminated 30 hours after the application of this hormone. Group 2; considered the control group in which insemination was made 30 hours after the mares presented follicle equal o higher than 35 mm by means of the ultrasound observation. For the artificial insemination, frozen semen in straw of 5 mL containing a total concentration of 1000 million spermatozoa was used. The gestation diagnosis was made by means of the observation of the embryonic vesicle in day 16 after the artificial insemination, with a transrectal ultrasound of 5 MHz. The results show that group 1 (mares treatment with hCG) have an 80% fertility percentage (8/10), whereas group 2 (control group), presented a 20% fertility (2/10). It is concluded that hCG helped to improve the pregnancy percentage in treated mares. [ABSTRACT FROM AUTHOR]

The article presents a letter to the editor in response to the article "Serpiginous Choroiditis in a Patient with Systemic Lupus Erythematosus," by G Fuentes-Paez, J Celis-Sanchez, J Torres, H Martinez-Osorio, and JM Herreras.

We observed that in isolated perfused rat kidneys, sphingosine-1-phosphate produces S1P(2) receptor-mediated vasoconstriction, and this response increased in kidneys of diabetic rats. These results suggest that the antagonists of S1P(2) receptor may have potential as drugs to control diabetes-induced vascular complications. [ABSTRACT FROM AUTHOR]