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Photocatalysis is an advanced oxidation process that is an environmentally friendly option and one of the most critical technologies in green chemistry today. This work studied the upscaling of photocatalysis as a suitable process for wastewater treatment to remove emerging pollutants. For this purpose, unsupported and supported TiO2 photocatalysts were tested in the photodegradation of ciprofloxacin as a model molecule of an emerging wastewater component, using visible, UV radiation, and solar light. The suitability of TiO2 as a photocatalyst to decompose ciprofloxacin was confirmed in batch photoreactor under Visible and UV radiation, with degradation rates up to 90% after 30 min of irradiation and low adsorption values. TiO2 as a photocatalyst coated in glass support material at the packed bed photoreactor showed good photoactivity for emergent contaminants degradation (95%) under solar radiation. It has been possible to verify that the photocatalytic reactor system constitutes a viable process for eliminating emerging contaminants through environmentally sustainable treatments. Our results corroborate the possibility of degrading emerging contaminants by solar radiation using a packed bed photoreactor, providing a more effective option from a practical and economical point of view for wastewater effluent treatments. [ABSTRACT FROM AUTHOR]

Recently, photocatalysis has been demonstrated as a solid approach for efficient wastewater cleaning. Using natural materials as photocatalysts means a promising solution to develop green catalysts for environmental purposes. This work aimed to study the suitability of a natural volcanic material (La Gomera, Canary Islands, Spain) as a photocatalytic material for the degradation of pollutants in wastewater with solar energy. After analysing the properties of the natural material (BET surface 0.188 m 2 /g and band-gap of 3 eV), the photocatalytic activity was evaluated at laboratory and pilot plant scale for the degradation of methylene blue (MB) in water (50 mg L -1 ), at 20 °C, during a period of 4 h, under UV/Vis light and solar irradiation. Photolytic and adsorption studies were developed to distinguish the photocatalytic contribution to the wastewater decontamination process by photocatalysis. Our results enable us to determine the viability of black sand as a photocatalytic material activated by solar irradiation (photodegradation of MB up to 100% by using solar energy), developing a natural and green photocatalytic system with significantly high potential for application in a sustainable wastewater cleaning process.

The polyolefin to lighter molecules reaction reduces the waste-plastic residues to produce fuels and valuable chemicals. Commercial MgO light and CaO were used as catalysts for the direct polyethylene and polypropylene liquefaction in N 2 or CO 2 atmospheres. The products were analyzed (ATR-FTIR, GC-FID/TCD, GC-FID, density, refractive index). The use of MgO light and CaO improved the conversion of propylene and ethylene to liquid products. In addition, low gaseous and solid products yields were obtained. A good production of organic liquids in the gasoline, diesel and kerosene boiling range was obtained. The use of CO 2 , in some cases, led to a higher conversion into liquids compared with the reactions performed in the N 2 atmosphere. In addition, the use of the CO 2 atmosphere led to a higher content of products with a boiling range in the diesel and kerosene ranges.

Phonolite material has shown to be promising catalyst support for the deoxygenation of triglycerides. In this work, we continue with our previous research by synthesising and testing three acid-treated phonolite-supported Co-Mo, Ni-Mo and Ni-W catalysts for the hydrotreating of atmospheric gas oil and co-processing with rapeseed oil at industrial operating conditions (350-370 °C, WHSV 1-2 h -1 , 5.5 MPa) in the continuous regime for more than 270 h. The phonolite-supported catalysts showed hydrotreating activity comparable with commercial catalysts, together with a complete conversion of triglycerides into n-alkanes. During co-processing, the Ni-promoted catalyst showed strong stability, with similar activity previous to the rapeseed oil addition. Our results enable us to evaluate the suitability of phonolite as catalyst support for the development of plausible alternatives to conventional hydrotreating catalysts for the co-processing of middle distillates with vegetable oils.

The Fischer-Tropsch heavy fraction is a potential feedstock for transport-fuels production through co-processing with fossil fuel fraction. However, there is still the need of developing new and green catalytic materials able to process this feedstock into valuable outputs. The present work studies the co-hydrocracking of the Fisher-Tropsch heavy fraction (FT-res.) with vacuum gas oil (VGO) at different ratios (FT-res. 9:1 VGO, FT-res. 7:3 VGO, and FT-res. 5:5 VGO) using phonolite-based catalysts (5Ni10W/Ph, 5Ni10Mo/Ph, and 5Co10Mo/Ph), paying attention to the overall conversion, yield, and selectivity of the products and properties. The co-processing experiments were carried out in an autoclave reactor at 450 °C, under 50 bars for 1 and 2 h. The phonolite-based catalysts were active in the hydrocracking of FT-res.:VGO mixtures, presenting different yields to gasoline, diesel, and jet fuel fractions, depending on the time of reaction and type of catalyst. Our results enable us to define the most suitable metal transition composition for the phonolite-based support as a hydrocracking catalyst.

Sulfur-free molybdenum carbides have the potential to replace the conventional sulfided catalysts used for hydrotreating. For these catalysts, it is not necessary to add sulfur to maintain their activity. This fact makes it worthwhile to continue working on improving their hydrotreating efficiency. According to our previous studies, the addition of Co or Ni promotes the hydrotreating activity, but only significant in the case of hydrodesulfurization efficiency (up to 30%). To increase the hydrodenitrogenation efficiency, other promoters, such as phosphorus, can be added. However, most of the published studies do not focus on co-processing or only on hydrotreating of gas oil model molecules at a laboratory scale. In this paper, we build on our previous research by studying five sulfur-free phosphorus-modified MoCx/Al 2 O 3 catalysts (0.5, 1.5, 2.5, 3.5, and 4.5 wt %) for the hydrotreating of atmospheric gas oil and co-processing with rapeseed oil (5, 10, and 25 wt %) under industrial conditions (330-350 °C, 5.5 MPa, WHSV 1-2 h -1 ). A phosphorus content up to 1.5 wt % promoted the hydrodesulfurization (5-10%) and the hydrodenitrogenation (10-25%) efficiencies of catalysts. Moreover, the triglycerides addition did not significantly decrease the catalyst activity during co-processing. Therefore, our results enable us to define the range of phosphorus addition that enhances MoCx activity using industrial conditions and commercial feedstocks, pointing the way to develop a suitable and sulfur-free alternative to conventional hydrotreating catalysts., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

The use of renewable local raw materials to produce fuels is an important step toward optimal environmentally friendly energy consumption. In addition, the use of these sources together with fossil fuels paves the way to an easier transition from fossil to renewable fuels. The use of simple organic acids as hydrogen donors is another alternative way to produce fuel. The present work reports the use of oxalic acid as a hydrogen donor for the catalytic hydrodesulfurization of atmospheric gas oil and the deoxygenation of rapeseed oil at 350 °C. For this process, one commercial NiW/SiO 2 -Al 2 O 3 solid and two NiW/modified phonolite catalysts were used, namely Ni (5%) W (10%)/phonolite treated with HCl, and Ni (5%) W (10%)/phonolite treated with oxalic acid. The fresh phonolite catalysts were characterized by Hg porosimetry and N 2 physisorption, ammonia temperature programmed desorption (NH 3 -TPD), X-ray diffraction (XRD), and X-ray fluorescence (XRF). The sulfided metal phonolite catalysts were characterized by XRD and XRF. Hydrodesulfurization led to a decrease in sulfur content from 1 to 0.5 wt% for the phonolite catalysts and to 0.8 wt% when the commercial catalyst was used. Deoxygenation led to the production of 15 and 65 wt% paraffin for phonolite and commercial solids, respectively. The results demonstrate the potential of using oxalic acid as a hydrogen donor in hydrotreating reactions.

The medial preoptic area is a structure located in the hypothalamic anteroventral third ventricle region, and is closely related to the olfactory brain development and sexual differentiation of the brain. The medial preoptic area surrounds the organum vasculosum of the lamina terminalis, and both structures are the main areas where synthesis of gonadotropin-releasing hormone occurs in the brain. Neurons synthesizing gonadotropin-releasing hormone migrate from the medial nasal epithelium to the rostral brain and reach the organum vasculosum of the lamina terminalis and the medial preoptic area. Kallmann syndrome is a genetic disorder which combines hypogonadotropic hypogonadism and anosmia. Hypogonadism is characterized by the absence or reduced levels of gonadotropin-releasing hormone and anosmia due to olfactory bulb aplasia. This paper speculates on the connection between the development of the medial preoptic area, the organum vasculosum of the lamina terminalis and olfactory bulbs with Kallmann syndrome, since the anteroventral third ventricle region is crucial for the normal development of these structures and its connection with the olfactory nerves and sexual maturation., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The p73 proteins are present in different kinds of cells of the central nervous system, such as the choroid plexus, circumventricular structures and neuroepithelium. It has been reported that spontaneously hypertensive rats show ventricular dilation, changes in cerebrospinal fluid proteins and variations in the circumventricular structures such as the organum vasculosum of the lamina terminalis and the choroid plexus, which are altered in ventricular dilation. The aim of the present work is to study p73 expression in the organum vasculosum of the lamina terminalis and the choroid plexus and its variations in high blood pressure. Brains from control Wistar-Kyoto rats and spontaneously hypertensive rats were used. The organum vasculosum of the lamina terminalis and the choroid plexus were processed by immunohistochemistry and western blot with anti-TAp73. We found weaker markings in the organum vasculosum of the lamina terminalis and stronger markings in the choroid plexus of the hypertensive than the control rats. Therefore, hypertension in the spontaneously hypertensive rats produces alterations in choroid plexus protein p73 expression that is similar to that described for other circumventricular organs, but it is different in the organum vasculosum of the lamina terminalis. We can conclude that the functional balance between p73, organum vasculosum of the lamina terminalis and choroid plexus, which is probably necessary to maintain the normal functioning of these structures, is altered by the hypertension found in these rats.

Background: Aquaporin-4 (AQP4) is a water channel mainly located in the ventricular ependymal cells (brain-CSF barrier), the sub-ependymal glia, glia limitans and in end-feet of astrocytes in at the blood-brain barrier (BBB)., Methods: In the present work, the expression of AQP4 in the cerebrospinal fluid (CSF) in control and congenital human hydrocephalus infants (obstructive and communicating), was analysed by Western-blot and enzyme immunoassay (ELISA)., Results: AQP4 was found to be high compared to the control in the CSF in congenital hydrocephalus patients. Western-blot showed higher values for AQP4 than controls in communicating hydrocephalus (communicating: 38.3%, control: 6.9% p < 0.05) although the increase was not significant in obstructive hydrocephalus (obstructive: 14.7%). The AQP4 quantification by ELISA also showed that, the mean concentration of AQP4 in CSF was significantly higher in communicating hydrocephalus (communicating: 11.32 ± 0.69 ng/ml, control: 8.61 ± 0.31 ng/ml; p < 0.05). However, there was no increase over control in obstructive hydrocephalus (obstructive: 8.65 ± 0.80 ng/ml)., Conclusions: AQP4 has a modulatory effect on ependyma stability and acts in CSF production and reabsorption. Therefore, the increase of AQP4 in the CSF in congenital hydrocephalus could be due to the fact that AQP4 passes from the parenchyma to the CSF and this AQP4 movement may be a consequence of ependyma denudation.

Luteinizing hormone-releasing hormone (LHRH) neurons and fibers are located in the anteroventral hypothalamus, specifically in the preoptic medial area and the organum vasculosum of the lamina terminalis. Most luteinizing hormone-releasing hormone neurons project to the median eminence where they are secreted in the pituitary portal system in order to control the release of gonadotropin. The aim of this study is to provide, using immunohistochemistry and female brain rats, a new description of the luteinizing hormone-releasing hormone fibers and neuron localization in the anterior hypothalamus. The greatest amount of the LHRH immunoreactive material was found in the organum vasculosum of the lamina terminalis that is located around the anterior region of the third ventricle. The intensity of the reaction of LHRH immunoreactive material decreases from cephalic to caudal localization; therefore, the greatest immunoreaction is in the organum vasculosum of the lamina terminalis, followed by the dorsomedial preoptic area, the ventromedial preoptic area, and finally the ventrolateral medial preoptic area, and in fibers surrounding the suprachiasmatic nucleus and subependymal layer on the floor of the third ventricle where the least amount immunoreactive material is found.

The aim of the present work is to analyze the cerebrospinal fluid proteomic profile, trying to find possible biomarkers of the effects of hypertension of the blood to CSF barrier disruption in the brain and their participation in the cholesterol and β-amyloid metabolism and inflammatory processes. Cerebrospinal fluid (CSF) is a system linked to the brain and its composition can be altered not only by encephalic disorder, but also by systemic diseases such as arterial hypertension, which produces alterations in the choroid plexus and cerebrospinal fluid protein composition. 2D gel electrophoresis in cerebrospinal fluid extracted from the cistern magna before sacrifice of hypertensive and control rats was performed. The results showed different proteomic profiles between SHR and WKY, that α-1-antitrypsin, apolipoprotein A1, albumin, immunoglobulin G, vitamin D binding protein, haptoglobin and α-1-macroglobulin were found to be up-regulated in SHR, and apolipoprotein E, transthyretin, α-2-HS-glycoprotein, transferrin, α-1β-glycoprotein, kininogen and carbonic anhidrase II were down-regulated in SHR. The conclusion made here is that hypertension in SHR produces important variations in cerebrospinal fluid proteins that could be due to a choroid plexus dysfunction and this fact supports the close connection between hypertension and blood to cerebrospinal fluid barrier disruption.