The Impact of CeO2 Loading on the Activity and Stability of PdO/γ-AlOOH/γ-Al2O3 Monolith Catalysts for CH4 Oxidation

This study reports on the activity and stability of PdO/γ-AlOOH/γ-Al2O3 monolith catalysts, promoted with varying amounts of CeO2, for CH4 oxidation. Although the beneficial effects of CeO2 have been reported for powdered catalysts, this study used a cordierite (2MgO.2Al2O3.5SiO2) mini-monolith (400 cells per square inch, 1 cm diameter × 2.5 cm length; ~52 cells), washcoated with a suspension of γ-Al2O3 combined with boehmite (γ-AlOOH), followed by sequential deposition of Ce and Pd (0.5 wt.%) by wetness impregnation. The monolith catalysts’ CH4 oxidation activity and stability were assessed in the presence of CO, CO2, H2O and SO2 at low temperature (≤550 °C), relevant to emission control from lean-burn natural gas vehicles (NGVs). The CeO2 loading (0 to 4 wt.%) did not significantly impact the adhesion and thermal stability of the washcoat, but CeO2 reduced the inhibition of CH4 oxidation by H2O and SO2. The catalyst activity, measured by temperature-programmed methane oxidation (TPO) in a dry feed gas with 0.07 vol.% CH4, showed that adding CeO2 to the γ-AlOOH/γ-Al2O3 washcoat suppressed the activity of the catalysts; whereas, CeO2 improved the catalyst activity when H2O (2 and 5 vol.%) was present in the feed gas. Moreover, adding CeO2 decreased catalyst deactivation that occurred in the presence of 10 vol.% H2O and 5 ppmv SO2 at 500 °C, measured over a 25 h time-on-stream (TOS) period. The highest catalyst activity and stability for CH4 oxidation in the presence of H2O was obtained by adding 2 wt.% CeO2 to the washcoat.

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Hydrothermal Aging of Pd/LTA Monolithic Catalyst for Complete CH4 Oxidation

Catalysts ◽

10.3390/catal10050517 ◽

2020 ◽

Vol 10 (5) ◽

pp. 517 ◽

Cited By ~ 2

Author(s):

Ida Friberg ◽

Aiyong Wang ◽

Louise Olsson

Keyword(s):

Water Vapor ◽

Catalyst Deactivation ◽

Oxidation Catalyst ◽

X Ray Diffraction ◽

Ch4 Oxidation ◽

Hydrothermal Aging ◽

Oxidation Activity ◽

X Ray ◽

Lta Zeolite ◽

Surface Hydroxyls

Palladium-based catalysts are known to provide high CH4 oxidation activity. One drawback for these materials is that they often lose activity in the presence of water vapor due to the formation of surface hydroxyls. It is however possible to improve the water vapor tolerance by using zeolites as support material. In this study, we have investigated Pd supported on thermally stable LTA zeolite with high framework Si/Al ratio (Si/Al = ~44) for CH4 oxidation and the effect of hydrothermal aging at temperatures up to 900 °C. High and stable CH4 oxidation activity in the presence of water vapor was observed for Pd/LTA after hydrothermal aging at temperatures ≤ 700 °C. However, aging at temperatures of 800–900 °C resulted in catalyst deactivation. This deactivation was not a result of structural collapse of the LTA zeolite as the LTA zeolite only showed minor changes in surface area, pore volume, and X-ray diffraction pattern after 900 °C aging. We suggest that the deactivation was caused by extensive formation of ion-exchanged Pd2+ together with Pd sintering. These two types of Pd species appear to have lower CH4 oxidation activity and to be more sensitive to water deactivation compared to the well dispersed Pd particles observed on the LTA support prior to the hydrothermal aging. By contrast, Pd/Al2O3 was generally sensitive to water vapor no matter of the aging temperature. Although the aging caused extensive Pd sintering in Pd/Al2O3, only minor deterioration of the CH4 oxidation activity was seen. The results herein presented show that Pd/LTA is a promising CH4 oxidation catalyst, however Pd rearrangement at high temperatures (≥800 °C) is one remaining challenge.

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HBOT Application at Cases of Gingival Inflammation

Journal of Dentistry and Oral Sciences ◽

10.37191/mapsci-2582-3736-1(3)-017 ◽

2019 ◽

Author(s):

Ilma Robo

Keyword(s):

Root Resorption ◽

Periodontal Diseases ◽

Therapeutic Effects ◽

Clinical Effects ◽

Gingival Inflammation ◽

Beneficial Effects ◽

New Therapeutic Approaches ◽

Short Period ◽

Mechanical Therapy ◽

The Impact

The treatment of periodontal diseases, mainly of their origin, with the most common clinical manifestation in form of gingival inflammation, is manifold and powerful, including: mechanical therapy, antibiotic, antiseptic and various approaches to treatment, which are recommended to be used within a short period of time. New therapeutic approaches have been proven as alternative treatment to conventional therapy, or in combination with conventional therapies, to reduce the number of periodontopathic pathogens in gingival sulcus. HBOT has a detrimental effect on periodontal microorganisms, as well as beneficial effects on the healing of periodontal tissue, increasing oxygen pressure in gingival pockets. Our study is aimed at reviewing the current published literature on hyperbaric oxygen therapy and focuses on role of HBOT as a therapeutic measure for the individual with periodontal disease in general and for the impact on the recovery of gingival inflammation. HBOT and periodontal treatment together, reduce up to 99% of the gram-negative anaerobic load of subgingival flora. HBOT, significantly reduces subgingival anaerobic flora. Clinical effects in 2-year follow-up of treated patients are sensitive. Reduction of gingival hemorrhage indexes, depth of peritoneum, plaque index, occurs in cases of combination of HBOT and detraction. Reduced load persists up to 2 months after therapy. The significant increase in connective tissue removal starts at the end of 2nd week, to achieve the maximum in week 3-6 of application. HBOT used for re-implantation, stimulates the healing of periodontal membrane, pulp, prevents root resorption, healing of periodontal lining tissues. HBOT, significantly reduces the hemorrhage index with 1.2 value difference, 0.7mm probe depth, reduces gingival fluid by 2. HGH exposure is increased by gingival blood flow, with a difference of 2 in measured value. The therapeutic effects of HBOT in the value of the evaluation index can be saved up to 1-year post treatment.

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Evaluation of the Impact of Fatty Acid Methyl Ester (FAME) Contamination on the Thermal Stability of Jet A

10.21236/ada594760 ◽

2013 ◽

Author(s):

Jr Morris ◽

Shardo Robert W. ◽

Higgins James ◽

Cook Kim ◽

Tanner Rhonda ◽

...

Keyword(s):

Thermal Stability ◽

Fatty Acid ◽

Methyl Ester ◽

Fatty Acid Methyl Ester ◽

Acid Methyl Ester ◽

Acid Methyl ◽

The Impact ◽

Thermal Stability Of

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Relation between cognitive disorders and type of physical activity: Results of the FréLE cohort

European Journal of Public Health ◽

10.1093/eurpub/ckaa165.883 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

C Dupré ◽

N Barth ◽

A El Moutawakkil ◽

F Béland ◽

F Roche ◽

...

Keyword(s):

Physical Activity ◽

Cognitive Decline ◽

Proportional Hazards ◽

Cognitive Disorders ◽

The Elderly ◽

Cognitive Status ◽

Global Test ◽

Professional Activities ◽

Beneficial Effects ◽

The Impact

Abstract Background Few previous cohorts have studied the different type of physical activities and the degree of cognitive decline. The objective of this work was to analyze the leisure, domestic and professional activities with mild and moderate cognitive disorders in older people living in community. Methods The study used data from the longitudinal and observational study, FrèLE (FRagility: Longitudinal Study of Expressions). The collected data included: socio-demographic variables, lifestyle, and health status (frailty, comorbidities, cognitive status, depression). Cognitive decline was assessed by using: MMSE (Mini-Mental State Examination) and MoCA (Montreal Cognitive Assessment). MoCA was used with two cut-offs (26 and 17) so as to define mild and moderate cognitive disorders Physical activity was assessed by the PASE (Physical Activity Scale for the Elderly), structured in three sections: leisure, domestic and professional activities. Spline and proportional hazards regression models (Cox) were used to estimate the risk of cognitive disorders. Results At baseline, 1623 participants were included and the prevalence of cognitive disorders was 6.9% (MMSE) and 7.2% (MoCA), mild cognitive disorders was 71.3%. The mean age was 77 years, and 52% of the participants were women. After a 2 years long follow-up, we found 6.9% (MMSE) and 6% (MoCA) cognitive disorders on participants. Analyses showed that domestic activities were associated to cognitive decline (HR = 0.52 [0.28-0.94] for MMSE and HR = 0.48 [0.28-0.80] for MoCA). No association were found with leisure and professional activities, and no spline were significant with mild cognitive disorders. Conclusions Analysis showed a relationship between cognitive disorders and type of physical activity, thanks to the use of specific questionnaire of elderly and two global test of cognition. These findings will contribute to the debate on the beneficial effects of physical activity on cognition. Key messages This work allowed to compare two test of cognition and their link with physical activity. It contributes to the debate on the beneficial effects of physical activity on cognition. The work allowed us to see the effect of the different types of physical activity and the impact of the statistical method on the results.

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Microstructure and Durability Performance of Mortars with Volcanic Powder from Calbuco Volcano (Chile) after 4 Hardening Years

Materials ◽

10.3390/ma14071751 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1751

Author(s):

Rosa María Tremiño ◽

Teresa Real-Herraiz ◽

Viviana Letelier ◽

José Marcos Ortega

Keyword(s):

Water Absorption ◽

Thermal Analyses ◽

Length Change ◽

Cement Industry ◽

Chloride Diffusion ◽

Beneficial Effects ◽

State Diffusion ◽

Calbuco Volcano ◽

Reference Specimens ◽

The Impact

One of the most popular ways to lessen the impact of the cement industry on the environment consists of substituting clinker by additions. The service life required for real construction elements is generally long, so it would be interesting to obtain information about the effects of new additions after a hardening period of several years. Analyzed here are the effects of the incorporation of volcanic ashes, coming from Calbuco volcano’s last eruption (Chile), as clinker replacement, in the durability and pore structure of mortars, after approximately 4 hardening years (1500 days), in comparison with reference specimens without additions. The substitution percentages of clinker by volcanic powder studied were 10% and 20%. The microstructure was characterized with mercury intrusion porosimetry and impedance spectroscopy. In order to evaluate the pozzolanic activity of the volcanic powder after 1500 days, differential thermal analyses were performed. Water absorption after immersion, steady-state diffusion coefficient and length change were also studied. In accordance with the results obtained, the 10% and 20% substitution of clinker by volcanic powder from the Calbuco volcano showed beneficial effects in the mortars after 4 years, especially regarding the microstructure and chloride diffusion, without noticeable influence in their water absorption.

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Reproduction and biomarker responses of Eisenia fetida after exposure to imidacloprid in biochar-amended soil

Biochar ◽

10.1007/s42773-021-00103-4 ◽

2021 ◽

Author(s):

Ngitheni Winnie-Kate Nyoka ◽

Ozekeke Ogbeide ◽

Patricks Voua Otomo

Keyword(s):

Eisenia Fetida ◽

Field Studies ◽

Application Rate ◽

Land Application ◽

Acetylcholinesterase Inhibition ◽

Beneficial Effects ◽

Pesticide Pollution ◽

The One ◽

The Impact ◽

Amended Soil

AbstractTerrestrial and aquatic ecosystems are increasingly threatened by pesticide pollution resulting from extensive use of pesticides, and due to the lack of regulatory measures in the developing world, there is a need for affordable means to lessen environmental effects. This study aimed to investigate the impact of biochar amendment on the toxicity of imidacloprid to life-cycle parameters and biomarker responses of the earthworm Eisenia fetida. E. fetida was exposed to 10% biochar-amended and non-amended OECD artificial soils spiked with 0, 0.75, 1.5, 2.25 and 3 mg imidacloprid/kg for 28 days. An LC50 of 2.7 mg/kg was only computed in the non-amended soil but not in the biochar-amended soil due to insignificant mortality. The EC50 calculated in the non-amended soil (0.92 mg/kg) for reproduction (fertility) was lower than the one computed in the biochar amended (0.98 mg/kg), indicating a decrease in toxicity in the biochar-amended substrate. Significant weight loss was observed at the two highest imidacloprid treatments in the non-amended soil and only at the highest treatment in the biochar-amended substrate, further highlighting the beneficial effects of biochar. Catalase activity decreased significantly at the two highest concentrations of non-amended soil. Yet, in the amended soil, the activity remained high, especially in the highest concentration, where it was significantly higher than the controls. This indicated more severe oxidative stress in the absence of biochar. In all non-amended treatments, there was a significant acetylcholinesterase inhibition, while lower inhibition percentages were observed in the biochar-amended soil. In most endpoints, the addition of biochar alleviated the toxic effects of imidacloprid, which shows that biochar has the potential to be useful in soil remediation. However, there is still a need for field studies to identify the most effective application rate of biochar for land application.

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Exogenous application of growth stimulators improves the condition of maize exposed to soil drought

Acta Physiologiae Plantarum ◽

10.1007/s11738-021-03232-2 ◽

2021 ◽

Vol 43 (4) ◽

Author(s):

Agnieszka Ostrowska ◽

Maciej T. Grzesiak ◽

Tomasz Hura

Keyword(s):

Plant Growth ◽

Developmental Stages ◽

Aminolevulinic Acid ◽

Stem Elongation ◽

Development Stage ◽

Photochemical Activity ◽

Soil Drought ◽

Beneficial Effects ◽

Induced Changes ◽

The Impact

AbstractSoil drought is a major problem in plant cultivation. This is particularly true for thermophilic plants, such as maize, which grow in areas often affected by precipitation shortage. The problem may be alleviated using plant growth and development stimulators. Therefore, the aim of the study was to analyze the effects of 5-aminolevulinic acid (5-ALA), zearalenone (ZEN), triacontanol (TRIA) and silicon (Si) on water management and photosynthetic activity of maize under soil drought. The experiments covered three developmental stages: three leaves, stem elongation and heading. The impact of these substances applied during drought stress depended on the plant development stage. 5-ALA affected chlorophyll levels, gas exchange and photochemical activity of PSII. Similar effects were observed for ZEN, which additionally induced stem elongation and limited dehydration. Beneficial effects of TRIA were visible at the stage of three leaves and involved leaf hydration and plant growth. A silicon preparation applied at the same developmental stage triggered similar effects and additionally induced changes in chlorophyll levels. All the stimulators significantly affected transpiration intensity at the heading stage.

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Aerobic Exercise Induces Alternative Splicing of Neurexins in Frontal Cortex

Journal of Functional Morphology and Kinesiology ◽

10.3390/jfmk6020048 ◽

2021 ◽

Vol 6 (2) ◽

pp. 48

Author(s):

Elisa Innocenzi ◽

Ida Cariati ◽

Emanuela De Domenico ◽

Erika Tiberi ◽

Giovanna D’Arcangelo ◽

...

Keyword(s):

Alternative Splicing ◽

Aerobic Exercise ◽

Frontal Cortex ◽

Molecular Mechanisms ◽

Splice Variants ◽

Brain Regions ◽

Synaptic Function ◽

Molecular Changes ◽

Beneficial Effects ◽

The Impact

Aerobic exercise (AE) is known to produce beneficial effects on brain health by improving plasticity, connectivity, and cognitive functions, but the underlying molecular mechanisms are still limited. Neurexins (Nrxns) are a family of presynaptic cell adhesion molecules that are important in synapsis formation and maturation. In vertebrates, three-neurexin genes (NRXN1, NRXN2, and NRXN3) have been identified, each encoding for α and β neurexins, from two independent promoters. Moreover, each Nrxns gene (1–3) has several alternative exons and produces many splice variants that bind to a large variety of postsynaptic ligands, playing a role in trans-synaptic specification, strength, and plasticity. In this study, we investigated the impact of a continuous progressive (CP) AE program on alternative splicing (AS) of Nrxns on two brain regions: frontal cortex (FC) and hippocampus. We showed that exercise promoted Nrxns1–3 AS at splice site 4 (SS4) both in α and β isoforms, inducing a switch from exon-excluded isoforms (SS4−) to exon-included isoforms (SS4+) in FC but not in hippocampus. Additionally, we showed that the same AE program enhanced the expression level of other genes correlated with synaptic function and plasticity only in FC. Altogether, our findings demonstrated the positive effect of CP AE on FC in inducing molecular changes underlying synaptic plasticity and suggested that FC is possibly a more sensitive structure than hippocampus to show molecular changes.

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Do Public Pensions Improve Mental Wellbeing? Evidence from the New Rural Society Pension Insurance Program

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052391 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2391

Author(s):

Fang Wang ◽

Haitao Zheng

Keyword(s):

Mental Health ◽

Rural Society ◽

Rural Elderly ◽

Public Pensions ◽

Mental Wellbeing ◽

Elderly Persons ◽

Pension Insurance ◽

Beneficial Effects ◽

Pension Income ◽

The Impact

The causal effect of public pensions on the mental wellbeing of the elderly in lower and middle-income countries deserves further investigation. This paper first constructed a theoretical framework for the impact of New Rural Society Pension Insurance pensions in China on the mental wellbeing of the rural elderly, and described potential channels through which pension income may affect mental wellbeing. We then used the fixed effect model and the instrument variable approach to estimate the casual effects of pension income on the mental wellbeing of the rural elderly. The results reveal that pension income improves mental wellbeing by relieving depression of the rural elderly; however, the beneficial effects of pension income are very limited. Pension income has no beneficial effects on the mental health of the rural elderly in the east region, whereas it slightly relieves depression of those in the middle and west regions. We also found that pension income produces small improvements in the mental health of older females, elderly persons living independently, and those with relatively poor economic conditions.

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The Impact of Oxidative Stress on Blood-Retinal Barrier Physiology in Age-Related Macular Degeneration

Cells ◽

10.3390/cells10010064 ◽

2021 ◽

Vol 10 (1) ◽

pp. 64

Author(s):

Annamaria Tisi ◽

Marco Feligioni ◽

Maurizio Passacantando ◽

Marco Ciancaglini ◽

Rita Maccarone

Keyword(s):

Oxidative Stress ◽

Macular Degeneration ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Age Related Macular Degeneration ◽

Blood Retinal Barrier ◽

Functional Changes ◽

Beneficial Effects ◽

Age Related ◽

The Impact

The blood retinal barrier (BRB) is a fundamental eye component, whose function is to select the flow of molecules from the blood to the retina and vice-versa, and its integrity allows the maintenance of a finely regulated microenvironment. The outer BRB, composed by the choriocapillaris, the Bruch’s membrane, and the retinal pigment epithelium, undergoes structural and functional changes in age-related macular degeneration (AMD), the leading cause of blindness worldwide. BRB alterations lead to retinal dysfunction and neurodegeneration. Several risk factors have been associated with AMD onset in the past decades and oxidative stress is widely recognized as a key factor, even if the exact AMD pathophysiology has not been exactly elucidated yet. The present review describes the BRB physiology, the BRB changes occurring in AMD, the role of oxidative stress in AMD with a focus on the outer BRB structures. Moreover, we propose the use of cerium oxide nanoparticles as a new powerful anti-oxidant agent to combat AMD, based on the relevant existing data which demonstrated their beneficial effects in protecting the outer BRB in animal models of AMD.

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