Search

The rise in carbon dioxide concentration is a primary anthropogenic source of severe climate change and ecological issues. Catalytic hydrogenation of CO2 into value-added chemicals and fuels including methanol is one of the attractive environmentally friendly ways to valorize carbon-containing feedstock and reduce global CO2 emissions. However, enhancing catalytic activity to achieve high methanol yield and selectivity while maintaining stability remains a major challenge. This study investigated the promotion of Cu/MOF-5 catalysts with varying loadings of ZrO₂ to determine its effects on catalytic performance in CO₂ hydrogenation. The copper loading was kept constant while the ZrO₂ content on the MOF-5 support was varied via the impregnation method. The addition of ZrO₂ was found to influence the BET surface area, suggesting the presence of amorphous ZrO₂, as its crystalline phases were not detected in x-ray diffractograms. Catalytic results demonstrated that ZrO₂ addition enhanced the catalytic activity, with increased CO₂ conversion up to 13.2 %. The results showed a correlation between catalytic performance and the reducibility of the active metal, driven by the amount of ZrO₂ present. The catalyst with the highest ZrO₂ loading exhibited the best performance, attributed to its increased surface area and enhanced reducibility. Under optimized conditions (GHSV of 1350 h⁻¹, temperature of 200 °C, and pressure of 30 bar), the catalyst achieved 100 % methanol selectivity. This study underscores the significant role of ZrO₂ as a promoter in enhancing the activity and selectivity of Cu/MOF-5 catalysts, providing critical insights into the design of efficient catalytic systems for CO₂ hydrogenation.

The influence of the support on catalytic activity and stability of supported 2Cr-Fe bimetallic catalysts for the CO2-assisted dehydrogenation (DH) of n-octane has been investigated. Four MgO modified supports viz; MgO-CeO2 (MgCe), MgO-ZrO2 (MgZr), MgO-CeO2-ZrO2 (MgCeZr) and MgO-SiO2 (MgSi) were synthesized by the sol-gel combustion technique. The supported catalysts were in turn prepared by vacuum impregnation and thereafter tested for the CO2-assisted DH of n-octane. The catalysts were characterized by inductively coupled plasma optical emission spectroscopy (ICP-OES), X-ray diffraction (XRD), N2-physisorption, Raman spectroscopy, transmission electron microscopy (TEM), electron dispersive x-ray (EDX), temperature programmed desorption of CO2 (CO2-TPD), temperature programmed reduction and oxidation (H2-TPR and CO2-TPO), electron paramagnetic resonance (EPR) and thermal gravimetric analysis (TGA) techniques. Raman results showed that the CrOx is stabilized as mono- and/or polynuclear Cr(VI) species over the 2Cr-Fe/MgCe catalyst, which are reduced to lower oxidation state species during the DH reaction. The 2Cr-Fe/MgZr, 2Cr-Fe/MgCeZr and 2Cr-Fe/MgSi catalysts stabilized the CrOx as polymerized species, forming the more active Cr-O-Fe polymer units on the catalysts’ surface. XRD, TEM and EDX results showed that the ZrO2-containing supports have smaller particles and stabilized the active metal oxides in a more dispersed amorphous state. The CO2-TPO of the pre-reduced catalysts and EPR of the used catalysts indicated that the 2Cr-Fe/MgCeZr undergoes significant re-oxidation by CO2 during the catalytic process. The 2Cr-Fe/MgCe was the least active, while the 2Cr-Fe/MgZr catalyst showed the best performance and stability over three regeneration cycles. Selectivity to C8 products (octenes and aromatics) was found to strongly depend on the surface basicity of the catalysts. Deactivation of the catalysts was found to follow first order kinetics and coke deposition was identified as the major cause.

Summary:. Integration of artificial intelligence (AI), specifically with natural language processing and machine learning, holds tremendous potential to enhance both clinical practices and administrative workflows within plastic surgery. AI has been applied to various aspects of patient care in plastic surgery, including postoperative free flap monitoring, evaluating preoperative risk assessments, and analyzing clinical documentation. Previous studies have demonstrated the ability to interpret current procedural terminology codes from clinical documentation using natural language processing. Various automated medical billing companies have used AI to improve the revenue management cycle at hospitals nationwide. Additionally, AI has been piloted by insurance companies to streamline the prior authorization process. AI implementation holds potential to enhance billing practices and maximize healthcare revenue for practicing physicians.

Mono- and di-substituted cerium oxide catalysts, viz. Ce0.95Cu0.05O2-δ, Ce0.90Cu0.10O2-δ, Ce0.90 Cu0.05Mn0.05O2-δ, Ce0.85Cu0.10Mn0.05O2-δ, and Ce0.80Cu0.10Mn0.10O2-δ, were synthesized via a one-step urea-assisted solution combustion method. The elemental composition and textural and structural properties of the catalysts were determined by various physical, electronic, and chemical characterization techniques. Hydrogen temperature-programmed reduction showed that co-doping of copper and manganese ions into the CeO2-δ lattice improved the reducibility of copper. Powder XRD, XPS, HR-TEM, and Raman spectroscopy showed that the catalysts were a singled-phased, solid-solution metal oxide with a cerium oxide cubic fluorite (cerianite) structure, and evidence of oxygen vacancies was observed. Catalytic results in the preferential oxidation of CO in a hydrogen-rich stream showed that complete CO conversion occurred between 150 and 180 °C. Furthermore, at 150 °C, Ce0.90Cu0.05Mn0.05O2-δ, Ce0.90 Cu0.10O2-δ, and Ce0.85Cu0.10Mn0.05O2-δ catalysts were the most active, achieving complete CO conversion and CO2 selectivity of 81, 79, and 71%, respectively. The catalysts performed moderately in the presence of CO2 and water, with the Ce0.90Cu0.05Mn0.05O2-δ catalyst giving a CO conversion of 80% in CO2, which decreased to about 60% when water was added.

A series of new chelating bidentate (SS) alkylimidazole-2-thione-Ru(II)/Os(II) complexes (3ai, 3aii, 3aiii, 3bii/4aiii, 4bi, 4bii), and the tridentate (SNS) pyridine-2,6-diylimidazole-2-thione-Ru(II)/Os(II) complexes (5bi, 5civ/6bi, 6ci, 6civ) in the forms [MII(cym)(L)Cl]PF6 and [MII(cym)(L)]PF6 (M = Ru or Os, cym = η6-p-cymene, and L = heterocyclic derivatives of thiourea) respectively, were successfully synthesized. Spectroscopic and analytical methods were used to characterize the complexes and their ligands. Solid-state single-crystal X-ray diffraction analyses revealed a “piano-stool” geometry around the Ru(II) or Os(II) centers in the respective complexes. The complexes were investigated for in vitro chemotherapeutic activities against human cervical carcinoma (HeLa) and the non-cancerous cell line (Hek293) using the MTT assay. The compounds 3aii, 5civ, 5bi, 4aiii, 6ci, 6civ, and the reference drug, 5-fluorouracil were found to be selective toward the tumor cells; the compounds 3ai, 3aiii, 3bii, 4bi, 4bii, and 6bi, which were found not to be selective between normal and tumor cell lines. The IC50 value of the tridentate half-sandwich complex 5bi (86 ± 9 μM) showed comparable anti-proliferative activity with the referenced commercial anti-cancer drug, 5-fluorouracil (87 ± 15 μM). The pincer (SNS) osmium complexes 6ci (36 ± 10 μM) and 6civ (40 ± 4 μM) were twice as effective as the reference drug 5-fluorouracil at the respective dose concentrations. However, the analogous pincer (SNS) ruthenium complex 5civ was ineffective and did not show anti-proliferative activity, even at a higher concentration of 147 ± 1 μM. These findings imply that the higher stability of the chelating (SS) and the pincer (SNS) ligand architectures in the complexes improves the biological (anti-proliferative) activity of the complexes by reducing the chance of ligand dissociation under physiological conditions. In general, the pincer (SNS) osmium complexes were found to be more cytotoxic than their ruthenium analogues, suggesting that the anti-proliferative activity of the imidazole-2-thione-Ru/Os complexes depends on the ligand’s spatial coordination, the nature of the metal center, and the charge of the metal complex ions.

There is a growing trend in social science research to share qualitative data in a repository for others to access. However, some researchers are reticent to share qualitative data. One major concern is how to de-identify qualitative data while maintaining adequate contextual detail to allow secondary users to meaningfully interpret de-identified data. To help inform discussions regarding qualitative data sharing, we reviewed 100 qualitative health science studies to determine what potentially identifying variables (PIVs) are reported in the published literature. There are relatively few PIVs reported in each qualitative study; the majority of studies (n=64) reported two or fewer PIVs. The most commonly reported PIVs were profession, sex or gender, and age. Our findings can help guide de-identification efforts going forward as presumably the PIVs that are most commonly reported provide essential contextual details that will also be needed by secondary users, while PIVs that are rarely reported may not provide essential contextual information for interpretation of data. This suggests it is possible to share qualitative data that are both de-identified and useful for secondary analysis. As data are shared, we recommend researchers mask study sites, as these may uniquely increase the chance of re-identification.

Abstract Introduction: Several evidence-informed consent practices (ECPs) have been shown to improve informed consent in clinical trials but are not routinely used. These include optimizing consent formatting, using plain language, using validated instruments to assess understanding, and involving legally authorized representatives when appropriate. We hypothesized that participants receiving an implementation science toolkit and a social media push would have increased adoption of ECPs and other outcomes. Methods: We conducted a 1-year trial with clinical research professionals in the USA (n = 1284) who have trials open to older adults or focus on Alzheimer’s disease. We randomized participants to receive information on ECPs via receiving a toolkit with a social media push (intervention) or receiving an online learning module (active control). Participants completed a baseline survey and a follow-up survey after 1 year. A subset of participants was interviewed (n = 43). Results: Participants who engaged more with the toolkit were more likely to have tried to implement an ECP during the trial than participants less engaged with the toolkit or the active control group. However, there were no significant differences in the adoption of ECPs, intention to adopt, or positive attitudes. Participants reported the toolkit and social media push were satisfactory, and participating increased their awareness of ECPs. However, they reported lacking the time needed to engage with the toolkit more fully. Conclusions: Using an implementation science approach to increase the use of ECPs was only modestly successful. Data suggest that having institutional review boards recommend or require ECPs may be an effective way to increase their use.

VOx/MgO catalysts, synthesised via solution combustion synthesis were developed for ODH of n-octane using urea, citric acid, hydrazine hydrate, oxalyldihydrazide and glycine as fuels. The effect of these fuels on influencing defects, surface VOx concentration, basic properties and redox properties using various analytical methods were studied. Notable differences in surface and bulk characteristics of the vanadates were observed due to the fuel employed, affecting conversion of octane and selectivity to ODH products. Glycine as fuel gave best octene selectivity due to ease of reducibility of the VOx species, medium surface basicity, and relatively high concentration of surface oxygen vacancies.

Summary: Here in we report the development of a Pt-V/CeO2 catalyst performing under mild conditions in amide hydrogenation. Ceria with different morphologies was employed as support in this study. We further developed a glycol-thermal technique that yields thermally stable quantum dot ceria, which can be applied as a support. A systematic investigation revealed the importance of proximity between the small crystalline hydrogenating sites (Pt) and oxophilic sites (V). The study showed that oxygen vacancies on the ceria surface oxidize both Pt and V, poisoning the hydrogenation reaction. In contrast, the absence of oxygen vacancies promoted the hydrogenating ability of Pt sites and also improved their ability to participate in the H2 spillover mechanism and in situ formation of oxophilic V3+. This study demonstrates how the engineering of the oxygen vacancies on the surface of the redox support can manipulate the nature of active sites toward specific reactions.

Motherhood induces a drastic, sometimes long-lasting, change in internal state and behavior in many female animals. How a change in reproductive state or the discrete event of mating modulates specific female behaviors is still incompletely understood. Using calcium imaging of the whole brain of Drosophila females, we find that mating does not induce a global change in brain activity. Instead, mating modulates the pheromone response of dopaminergic neurons innervating the fly’s learning and memory center, the mushroom body (MB). Using the mating-induced increased attraction to the odor of important nutrients, polyamines, we show that disruption of the female fly’s ability to smell, for instance the pheromone cVA, during mating leads to a reduction in polyamine preference for days later indicating that the odor environment at mating lastingly influences female perception and choice behavior. Moreover, dopaminergic neurons including innervation of the β’1 compartment are sufficient to induce the lasting behavioral increase in polyamine preference. We further show that MB output neurons (MBON) of the β’1 compartment are activated by pheromone odor and their activity during mating bidirectionally modulates preference behavior in mated and virgin females. Their activity is not required, however, for the expression of polyamine attraction. Instead, inhibition of another type of MBON innervating the β’2 compartment enables expression of high odor attraction. In addition, the response of a lateral horn (LH) neuron, AD1b2, which output is required for the expression of polyamine attraction, shows a modulated polyamine response after mating. Taken together, our data in the fly suggests that mating-related sensory experience regulates female odor perception and expression of choice behavior through a dopamine-gated learning circuit.

The effect of tetrabutylammonium nitrate ([N4444][NO3]) was studied as a surface coating over 1Pd9Ag/Al2O3 and applied in the selective hydrogenation of 1,7-octadiene in a mixture with 1-octene. Weight loadings up to a surface of three monolayers (MLs) were investigated and a further comparison coating with 1-ethylimidazole ([EIM]) was carried out to assess anionic effects in the Solid Catalysts with an Ionic Liquid Layer (SCILLs). Catalysts were characterised by H2-chemisorption, TGA-DSC, BET measurements, XPS, and HR-TEM. Catalytic studies showed that the uncoated and EIM-coated (10 wt%) catalysts gave nearly a 100% conversion of 1,7-octadiene and 1-octene with a selectivity mainly towards octane. Coating with [N4444][NO3] at 1 ML significantly decreased the 1-octene conversion by almost 50%, as well as the selectivity to octane (38%) at close to a 100% diene conversion. However, no net gain in 1-octene in the output stream was noted. At 2 ML IL/EIM coverage, a further decline in 1-octene conversion and octane selectivity was found at a diene conversion of 75%. The selectivity to 1-octene steadily increased from over the bare catalyst (52%) to the EIM-coated (62%) catalyst and SCILL (75%). At 3 ML IL coverage, the diene conversion (35%) was significantly reduced due to mass transfer limitations of hydrogen through the thick IL layer. Characterisation of the used catalysts by TG and BET analyses confirmed a leaching of up to 14% of the ionic liquid in the SCILLs coated at 1 ML and 2 ML, with an increase in surface area noted. Furthermore, smaller particle sizes of the used catalysts showed that the metal–support interaction was re-established. These results confirm a mild ligand coordination between the nitrogen in the IL anion and Pd and Ag where the ionic liquid remained physisorbed over the surface of the catalyst. In addition, component miscibility tests revealed partial solubility of the diene in the ionic liquid, indicating the presence of solvent effects also.

We conducted a qualitative content analysis of health science literature ( N = 100) involving qualitative interviews or focus groups. Given recent data sharing mandates, our goal was to characterize the nature of relationships between the researchers and participants to inform ethical deliberations regarding qualitative data sharing and secondary analyses. Specifically, some researchers worry that data sharing might harm relationships, while others claim that data cannot be analyzed absent meaningful relationships with participants. We found little evidence of relationship building with participants. The majority of studies involve single encounters (95%), lasting less than 60 min (59%), with less than half of authors involved in primary data collection. Our findings suggest that relationships with participants might not pose a barrier to sharing some qualitative data collected in the health sciences and speak to the feasibility in principle of secondary analyses of these data.

Cubic and rhombohedral phases of lanthanum manganite were synthesized in a high-pressure reactor. A mixture of La and Mn nitrates with ethylene glycol at a synthesis temperature of 200 °C and a calcination temperature of up to 1000 °C, resulted in a single-phase perovskite, LaMnO3 validated using X-ray diffraction. Significant changes in unit cell volumes from 58 to 353 Å3 were observed associated with structural transformation from the cubic to the rhombohedral phase. This was confirmed using structure calculations and resistivity measurements. Transmission electron microscopy analyses showed small particle sizes of approximately 19, 39, 45, and 90 nm (depending on calcination temperature), no agglomeration, and good crystallinity. The particle characteristics, high purity, and high surface area (up to 33.1 m2/g) of the material owed to the inherent PAAR reactor pressure, are suitable for important technological applications, that include the synthesis of perovskite oxides. Characteristics of the synthesized LaMnO3 at different calcination temperatures are compared, and first-principles calculations suggest a geometric optimization of the cubic and rhombohedral perovskite structures.

Oxidative dehydrogenation (ODH) of n-octane was carried out over a vanadium–magnesium oxide catalyst in a continuous flow fixed bed reactor. The catalyst was characterized by ICP–OES, powder XRD and SEM. The catalytic tests were carried out at different gas hourly space velocities (GHSVs), viz. 4000, 6000, 8000, and 10,000 h−1. The best selectivity for octenes was obtained at the GHSV of 8000 h−1, while that for C8 aromatics was attained at the GHSV of 6000 h−1 at high temperatures (500 and 550 °C). The catalytic testing at the GHSV of 10,000 h−1 showed the lowest activity, while that at the GHSV of 4000 h−1 consistently showed the lowest ODH selectivity. Generally, the best ODH performance was obtained by the catalytic testing at the GHSVs of 6000 and 8000 h−1. No phasic changes were observed after the catalytic testing. Keywords: VMgO, Dehydrogenation, Octenes, C8 aromatics

Breast cancer affects about one in eight women over the course of her lifetime. Occult breast cancer, in which primary breast cancer is detected without evidence of disease in the breast itself, comprises up to 1% of new diagnoses; this is typically detected from abnormal axillary lymph nodes, and distant metastases are rare. Here, we present an unusual case of occult breast cancer presenting as upper extremity pain, edema, and weakness, with a metastatic mass to the brachial plexus being the only site of disease.

Background:. Over the past decade, there has been a worldwide increase in plastic and reconstructive surgery research as well as increased interest in global collaboration. However, little is known about who is contributing to this global expansion or the trends of individual countries. The aim of our study was to analyze the output of Plastic and Reconstructive Surgery (PRS) over a decade to elucidate trends in the plastic surgery field. Methods:. The country of origin for all first authors of articles published by PRS from 2010 to 2019 were determined and date extracted using PubMed2XL. The change in frequency of publications over the decade by country, continental contributions, as well as state-level analysis within the United States were analyzed. Results:. From 2010 to 2019, there were a total number of 8680 publications with an increase in total articles from 747 to 1049 per year. 54 countries contributed over the decade, with the United States producing the most followed by Italy, China, Canada, and the UK. The top producing states were Texas, New York, California, Massachusetts, and Pennsylvania. Conclusions:. The last decade (2010–2019) saw a large international increase in research, not only with the total number of publications, but also in the diversity of originating country. Our work shows a shift away from a US-focused journal to incorporate more work from our international colleagues, as research is conducted in centers across the globe.

In this paper, we discuss the foundational values informing the Catholic perspective on decision-making for critically ill newborns and infants, particularly focusing on the prudent use of medical technologies. Although the Church has consistently affirmed the general good of advances in scientific research and medicine, the technocratic paradigm of medicine may, particularly in cases with severely ill infants, lead to decision-making conflicts and breakdowns in communication between parents and providers. By exploring two paradigm cases, we offer specific practices in which providers can engage to connect with parents and avoid common technologically mediated decision-making conflicts. By focusing on the inherent relationality of all human persons, regardless of debility, and the Christian hope in the life to come, we can make decisions in the midst of the technocratic paradigm without succumbing to it.

Magnesium oxide was prepared and used as a catalyst for the dehydrogenation of n-octane. The catalyst was characterized by ICP-OES, BET, powder XRD, IR, H2-TPR and SEM. The catalyst was tested for the oxidative dehydrogenation of n-octane using a continuous flow fixed bed reactor at a GHSV of 6000 h−1 and n-octane/oxygen (O2) molar ratio of 0.8. Octenes were found to be the dominant dehydrogenation products, with 2-octenes being the dominant isomers. Among the C8 aromatics, ethylbenzene was the most-formed product, followed by styrene and o-xylene. The aromatization of n-octane was predominantly through the C1–C6 mode of cyclization. Keywords: Magnesium oxide, n-Octane, Dehydrogenation, Cyclization

Mutilating hand trauma remains a challenge for reconstructive hand surgeons, owing to the involvement of multiple tissue types and segmental nature of these injuries. Principles of “spare parts” surgery may be useful in assessing how to make use of otherwise unsalvageable or functionless tissue. Pedicled heterotopic digit transposition is such a procedure; it may be safely performed in the acute posttraumatic setting. The historical basis for digit transposition and related techniques are reviewed. Two illustrative cases in which a single functional finger was created from 2 severely traumatized digits are presented. This reconstructive technique should be considered when a patent vascular pedicle, appropriate length, and intact articular surfaces are present in the donor digit. Digit transposition is a useful addition to the hand surgeon’s techniques for restoring posttraumatic hand function after mutilating injury. Key words: amputation, digit, hand trauma, reconstruction, replantation

CO hydrogenation and oxidation were conducted over Ir supported on TiO2 and ZrO2 catalysts using a feed mimicking the water–gas shift reformate stream. The influence of the support interaction with Ir and the catalysts’ redox and CO chemisorption properties on activity and selectivity were evaluated. Both catalysts oxidised CO to CO2 in the absence of H2, and a conversion of 70% was obtained at 200 °C. For the CO oxidation in the presence of H2 over these catalysts, the oxidation of H2 was favoured over CO due to H2 spillover occurring at the active metal and support interface, resulting in the formation of interstitials catalysed by Ir. However, both catalysts showed promising activity for CO hydrogenation. Ir-ZrO2 was more active, giving 99.9% CO conversions from 350 to 370 °C, with high selectivity towards CH4 using minimal H2 from the feed. Furthermore, results for the Ir-ZrO2 catalyst showed that the superior activity compared to the Ir-TiO2 catalyst was mainly due to the reducibility of the support and its interaction with the active metal. Controlling the isoelectric point during the synthesis allowed for a stronger interaction between Ir and the ZrO2 support, which resulted in higher catalytic activity due to better metal dispersions, and higher CO chemisorption capacities than obtained for the Ir-TiO2 catalyst.

The effect of the thermal treatment of some zeolitic materials was studied on oxidative dehydrogenation (ODH) of n-octane. Gallium containing faujasite catalysts were synthesized using isomorphic substitution, specifically, a galosilicalite (Ga-BaY(Sil)) and an aluminosilicalite substituted with gallium (Ga-BaY(IS)), with constant Si/M ratio. The catalysts were thermally treated at different temperatures (250, 550, and 750 °C) before catalytic testing. The quantification of total and strength of acid sites by FT-IR (O-H region), pyridine-IR, and NH3-temperature-programmed desorption (TPD) confirmed a decrease in the number of Brønsted acid sites and an increase in the number of Lewis acid sites upon increasing the calcination temperature. Isothermal n-octane conversion also decreased with the catalysts’ calcination temperature, whereas octene selectivity showed the opposite trend (also at iso-conversion). The COx selectivity showed a decrease over the catalysts calcined from 250 to 550 °C and then an increase over the 750 °C calcined catalysts, which was due to the strong adsorption of products to strong Lewis acid sites on the catalysts leading to the deep oxidation of the products. Only olefinic-cracked products were observed over the 750 °C calcined catalysts. This suggested that the thermal treatment increases Lewis acid sites, which activate n-octane using a bimolecular mechanism, instead of a monomolecular mechanism.

This work describes Ce0.89Zr0.03Pd0.08O2-δ as a heterogeneous catalyst for Heck-Mizoroki reactions. The material was synthesised by urea-assisted solution combustion to give a zirconium-stabilised cerium fluorite structure, with a fraction of palladium incorporated into the host structure. Characterisation techniques included ICP-OES, P-XRD and electron microscopy. The catalyst illustrated a high TOF of 1860 h−1 for the cross-coupling of iodobenzene with methyl acrylate, when trimethylamine (TEA) was used as a base and dimethylformamide (DMF) as the solvent at 130 °C. To establish the activity of coupling pairs, screening was limited to aryliodobenzenes, with various electronic properties, to determine the influence of aryliodobenzene electronic density on the trans product yield. Electron-donating substituents showed good yields, while electron-withdrawing groups had lower yields. Furthermore, various classes of electron-deficient olefins were screened to determine any effect on the trans product yield. Electron-deficient olefins showed higher yields with regard to the trans product than neutral styrene.

Non-coking stable alkaline earth metal (M = Mg, Sr, and Ba) modified Ga-NaY catalysts were prepared by ionic-exchange and tested in oxidative dehydrogenation (ODH) of n-octane using air as the source of oxygen. The role of the alkaline earth metals in NaY was to poison the acid sites while enhancing the basic sites responsible for ODH. The exception was the calcium modified NaY, which was more acidic than the parent NaY, coking and unstable under the ODH conditions used in this study. The role of gallium was to enhance the dehydrogenation pathway and improve the stability of NaY. The sequence of increasing selectivity to octenes followed the order: CaGa-NaY < Ga-NaY< MgGa-NaY < SrGa-NaY < BaGa-NaY. The highest octene selectivity obtained was 37% at iso-conversion of 6 ± 1% when BaGa-NaY was used at a temperature of 450 °C. The activity of the catalysts was directly proportional to the reducibility of the catalysts, which is in agreement with expectations.

Loss of the sense of smell is among the first signs of natural aging and neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Cellular and molecular mechanisms promoting this smell loss are not understood. Here, we show that Drosophila melanogaster also loses olfaction before vision with age. Within the olfactory circuit, cholinergic projection neurons show a reduced odor response accompanied by a defect in axonal integrity and reduction in synaptic marker proteins. Using behavioral functional screening, we pinpoint that expression of the mitochondrial reactive oxygen scavenger SOD2 in cholinergic projection neurons is necessary and sufficient to prevent smell degeneration in aging flies. Together, our data suggest that oxidative stress induced axonal degeneration in a single class of neurons drives the functional decline of an entire neural network and the behavior it controls. Given the important role of the cholinergic system in neurodegeneration, the fly olfactory system could be a useful model for the identification of drug targets.