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The conversion of methane or natural gas into turquoise H2 and carbon represents a promising pathway towards decarbonised energy. The pyrolysis of biogas (mainly a mixture of methane and CO2) is considered to be a negative carbon-emission technology, as the carbon source comes from biomass and the carbon is captured in solid form. In addition, the presence of CO2 in the gas mixture enables the dry reforming of methane into syngas. In this study, we show that direct biogas conversion in a fluidised catalytic reactor can produce a syngas whose composition meets the requirements for methanol synthesis or for liquid hydrocarbon production via the Fischer-Tropsch process. Confirmed by thermodynamic analysis, we show that the reaction proceeds at temperatures above 900 1C to produce carbon materials, whereas at lower temperatures the carbon is converted to CO by the Boudouard reaction. At 950 1C, very high methane and CO2 conversions are achieved (490% and 99%, respectively), accompanied by high hydrogen yield (490%) and the sequestration of carbon into a turbostratic structure. We believe that the direct catalytic reforming of biogas in a fluidised bed, when combined in series with an FTS process, could allow the production of liquid fuels with no need for costly gas separation units, in particular those implemented for CO2 capture. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuO-ZnO-ZrO 2 catalysts were prepared by co-precipitation method in batch. • Progressive substitution of ZnO by ZrO 2 in the catalyst largely affects the materials properties. • Catalytic activity tests of CO 2 hydrogenation to methanol were carried out at 50 bar in realistic mixtures suitable for industrial applications. • Optimal catalyst CZZ 66/34 showed methanol productivity of 725 g MeOH kg Cata −1 h−1 at 50 bar and 25,000 h−1. CuO-ZnO-ZrO 2 catalysts were synthetized by co-precipitation synthesis. Copper content in catalysts was kept constant (30 wt% of Cu °) and ZnO was gradually substituted by ZrO 2 in the support to have a greater understanding of the support's effect and to find the optimal ZnO/ZrO 2 ratio. These catalysts were fully characterized and then tested in the methanol synthesis via CO 2 hydrogenation. The effects of reaction temperature and GHSV on the catalytic behavior were investigated. The mix of the characterization results predicted the optimum support that is composed of 50 wt% of ZnO and 50 wt% of ZrO 2 with higher metallic copper surface area and higher copper dispersion. Surprisingly the optimum catalytic results were obtained for the 30Cu-ZZ 66/34 catalyst, whose support was composed of 66 wt% of ZnO and 34 wt% of ZrO 2. This catalyst presented good CO 2 conversion (19.6%) and methanol selectivity (50%), leading to a methanol productivity of 725 g MeOH kg Cata −1 h−1 at 280 °C, 50 bar and a GHSV of 25,000 h−1 (STP). Finally, the determining factor for the best catalytic activity is not the Zn/Zr ratio. To have the optimal catalytic activity in CO2 hydrogenation to methanol other parameters should be considered as well. They are: the nature and the state of copper species over the composite support; the homogeneity of the final composite sample, the ZnO particles size, and the number of ZnO-ZrO 2 interactions. The perfect combination of them all plays an important role in the determination of the best copper-based catalyst for the synthesis of methanol from CO 2. [ABSTRACT FROM AUTHOR]

Despite the development of selective catalyst formulations for oxidative coupling of methane (OCM), kinetic and reactor design studies have been hampered by a lack of data for truly isothermal reaction conditions. Because of the high exothermicity, the temperature of a fixed-bed reactor filled with Mn-Na 2 WO 4 /SiO 2 catalysts will show hot-spots with a loss of selectivity. The objective of this study is to measure catalyst activity under relevant reaction conditions of pressure (3 bar), biogas composition (no dilution) and contact time, while keeping the process isothermal. To this aim, we have synthesized and shaped a trilobed Mn-Na 2 WO 4 /α-Al 2 O 3 catalyst, which may be used as is at industrial scale, and measured its performance in a single-pellet reactor. We found that the presence of CO 2 did not degrade the catalyst performance, even on the long run, which should enable the use of a CO 2 -rich stream such as biogas. Actually, higher methane conversions have been obtained in the presence of CO 2 , likely due to a possible contribution of methane dry reforming reaction. We also noticed a slow catalyst activation over the first 100 h, while selectivity was kept constant. [Display omitted] • Oxidative methane coupling in the presence of carbon dioxide was studied. • A single pellet reactor was used to avoid temperature gradients. • Carbon dioxide does not impact the catalyst performance. • Opens the pathway for biogas applications. [ABSTRACT FROM AUTHOR]

A series of hybrid catalysts with different catalytic bed dispositions (layer bed and simple random mixture) of Cu-ZnO-Al 2 O 3 and SAPO-34 have been adopted and evaluated in syngas conversion into light C2-C4 hydrocarbons. An effect of the proximity between the two solids on the CO hydrogenation activity was demonstrated. A sphere contact quantification model was developed to estimate the concentration of contact between them for any simple random mixture. Comparing the evolution of gain of CO conversion (or hydrocarbon yield) with the theoretical results, it was shown that the density of contact was identified as the key factor for the catalytic performances (contact-activity relationship). Finally, the knowledge of the contact morphology, determined by FEG-SEM, allowed proposing the NH 3 -TPD as method characterizing the concentration of contact. [Display omitted] • The contacts between Cu-ZnO-Al 2 O 3 and SAPO-34 enhance the conversion of CO into hydrocarbons. • The CO conversion is markedly influenced by the balance between the two catalysts in simple random mixture arrangement. • A predictive model for the concentration of contacts quantification in simple random mixture was developed. • NH 3 -TPD was showed as method characterizing the concentration of contact. • Contact–activity relationship was established for layer bed and simple random mixture arrangements. [ABSTRACT FROM AUTHOR]

Introduction: Electronic cigarettes (e-cigs) have increased in popularity as a potentially less harmful alternative to tobacco smoking; however, the literature suggests "vaping" can cause endothelial damage, which can adversely affect erectile function. While there is a known link between smoking cigarettes and erectile dysfunction (ED), the effect of e-cigs on erectile function has been understudied., Objectives: To review the evidence for e-cig use causing endothelial dysfunction, to explore endothelial dysfunction as a potential mechanism for ED, and to determine if there is literature to support e-cigs as a cause of ED., Methods: A literature review was performed to identify publications pertaining to e-cig consumption and ED. Publications regarding e-cig consumption and vascular or endothelial damage were also included. The search was conducted through PubMed, MEDLINE database, the Cochrane Library Central Search, Web of Science, and Google Scholar. We identified 40+ publications for review, including 6 clinical trials and 3 basic science studies., Results: The literature suggests that e-cig use induces oxidative stress, including the direct formation of reactive oxygen species and hydroxyl radicals, leading to endothelial damage. Endothelial dysfunction is a potential mechanism for ED, but there is a paucity of studies evaluating the relationship between e-cig use and ED., Conclusion: E-cig use may cause ED in men, but more studies, specifically clinical trials, are needed to establish a relationship between e-cigs and ED. E-cig-induced endothelial dysfunction is a potential mechanism for ED that is worth exploring further. Pincus J, Sandoval V, Dick B, et al. E-Cigarette-Associated Endothelial Damage: A Potential Mechanism for Erectile Dysfunction. Sex Med Rev 2022;10:168-173., (Copyright © 2021 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose of Review: Self-induced genital trauma is rare, and prompt and evidence-based early intervention can improve the urinary and sexual function of these complex patients. This review has surveyed current literature and treatment trends to evaluate the clinical approach to managing genital trauma., Recent Findings: A literature review was performed regarding self-induced genitalia trauma and trauma management between 2000 and 2019 using MEDLINE® database, the Cochrane Library® Central Search, Web of Science, and Google Scholar. In total, 42 articles were considered relevant and included in this review. Self-induced trauma can be appropriately managed with a multidisciplinary approach. Treatment goals are to preserve urinary, sexual, and reproductive function. Specific evaluation includes mechanism of injury, imaging, and determining the extent of injury and surgical repair, if indicated. Due to the rarity of these injuries and their emergent nature, much of the management is based on retrospective data. Further research is needed to improve long-term functional outcomes in trauma patients.

Objective: To evaluate the ability of sperm DNA fragmentation index (DFI%) and high DNA stainability (HDS%) to influence the chance of achieving pregnancy in couples undergoing intracytoplasmic sperm injection (ICSI) cycles., Design: A retrospective study evaluating couples that underwent an ICSI cycle between 2009 - 2018., Setting: High-volume reproductive center., Patients: Consecutive couples who underwent an ICSI cycle and had a semen analysis with subsequent DFI% and HDS% testing, evaluated by Sperm Chromatin Structure Assay (SCSA)., Interventions: Measurement of DFI% and HDS% prior to ICSI cycle., Main Outcome Measures: To determine whether DFI% or HDS% of sperm was predictive of the number of ICSI cycles until the first clinical intrauterine pregnancy., Results: A total of 550 couples who underwent 1050 ICSI cycles were analyzed. Of those, a total of 330 couples achieved pregnancy. As expected, in couples that achieved pregnancy, females were younger (33.7 ± 3.6 years vs 35.3 ± 3.4 years; p < 0.001) and underwent fewer cycles (2 [1-2] vs 2 [1-3]; p =0.001). Importantly, the DFI% and HDS% were similar between couples who achieved pregnancy (DFI% = 12.9 [8-20]; HDS% = 9.3 [6.1-14.6]) and couples who did not (DFI% =12.2 [7.1-20.2]; HDS% = 9.1 [6.7-14]). A multivariable-adjusted analysis evaluating female age at the first cycle was negatively associated with pregnancy (OR = 0.827, 95% CI: 0.778 - 0.879; p < 0.001)., Conclusions: Neither DFI nor HDS at baseline influence the chances of a couple to achieve pregnancy after ICSI. Increased female age and couples who underwent more ICSI cycles were associated with lower chances of achieving pregnancy.

Background: The pterional approach (PA), together with its variants, is still one of the most common methods used by surgeons to reach the anterior and middle cranial base. A highly important technical detail during a PA is the preservation of the frontotemporal branch of the facial nerve, which can be achieved through an interfascial dissection., Objective: To describe the anatomy of the interfascial vein (IFV), highlighting its recognition as a significant anatomic reference to perform an interfascial dissection (IFD)., Methods: Eight adult cadaveric heads, fixed with formaldehyde and injected with colored silicone, were studied. In 6 heads, an IFD was performed, simulating a PA. In the 2 remaining heads, the IFV was dissected. In addition, an IFD was performed in 10 patients, studying the IFV anatomy., Results: In the 6 cadaveric heads in which the PA with an IFD was performed, and in the 10 patients who underwent a PA with an IFD, the IFV was found. If the interfascial space is divided into thirds, in all cases, the IFV was located within the middle third of the interfascial fat pad. On the 2 cadaveric heads in which the IFV was anatomically dissected, the IFV was also located within the middle third of the interfascial space., Conclusion: Recognizing the IFV in the interfascial space is of great help as an anatomic landmark to confirm that one is actually between both layers of the superficial temporal fascia., (Copyright © 2017 by the Congress of Neurological Surgeons)