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Introduction Hippocampus (HC) volume reductions have been a consistent finding in major depression (MDD). One possible mechanism that contribute to these reductions might be the inhibition of hippocampal neurogenesis through increased glucocorticoid stimulation following the chronic activation of the hypothalamo-pituitary stress axis (HPA) [1,2]. This is also supported by the fact that the resulting volume reductions can be partially reversed with antidepressant treatment [1,2] Furthermore, preclinical studies suggest that the effect of HPA dysregulation on hippocampal volume reduction, neurogenesis and their reversal by antidepressant response vary across hippocampal regions and are especially present in CA1, CA3 (atrophy of dendrites) and dentate gyrus (neurogenesis) [2]. Compatibly with this hypothesis, genetic variants influencing the endocrine stress axis in MDD, such as the FKBP5 glucocorticoid receptor regulator, were shown to be associated with brain structural changes, especially in the presence of environmental stressors such as early life stress (ELS) [3,4]. In accordance with the above mentioned findings we hypothesized that there might be a differential effect of early life stress on hippocampal subfields volumes in MDD patients with different allelic variants of FKBP5. To answer this question, we investigated whether patients exposed to childhood adversity and carrying the high-risk T allele of the rs1360780 polymorphism of FKBP5 showed smaller hippocampal volumes compared to C homozygous patients. Since CA1, CA3 and the dentate gyrus are especially affected by HPA axis alterations, we decided to focus on these hippocampal subfields. Methods We processed structural MRI data from 65 healthy controls (HC) and 91 MDD patients with automated hippocampal subfields segmentation using Freesurfer 5.3 for whole brain segmentation, followed by hippocampal subfields segmentation using Freesurfer 6 developer version. A quality check was performed using the ENIGMA hippocampal subfield protocols. We selected the following subfields for analysis: granule cells/molecular layer/dentate gyrus (GCMLDG), CA1, CA3, whole hippocampus (WH). ELS was evaluated with the Childhood Trauma Questionnaire Short Form. At least one mild expression of sexual abuse (subscale score > 7), emotional abuse (subscale score > 12) or physical abuse (subscale score > 9) was seen as having had a history of childhood abuse. We predicted the volume of each subfield using generalized linear scale response models, testing for the significance of between-group (diagnosis, ELS, allele status, age, sex, site, total intractranial volume) and within-group (side) factors. Results MDD patients showed reduced volume in all the subfields and in the total HC (p Conclusion In MDD, volume of CA1, CA3, DG and total HC was reduced. Patients with a high-risk variant in a glucocorticoid receptor regulator gene display smaller CA1 volumes in presence of ELS.

The total artificial heart (TAH) consists of two implantable pneumatic pumps that replace the heart and operate at a fixed ejection rate and ejection pressure. We evaluated the blood pressure (BP) response to exercise and exercise performance in patients with a TAH compared to those with a with a continuous-flow left ventricular assist device (LVAD).We conducted a single-center, retrospective study of 37 patients who received a TAH and 12 patients implanted with an LVAD. We measured the BP response during exercise, exercise duration and change in tolerated exercise workload over an 8-week period.In patients with a TAH, baseline BP was 120/69 ± 13/13, exercise BP was 118/72 ± 15/10 and post-exercise BP was 120/72 ± 14/12. Mean arterial BP did not change with exercise in patients with a TAH (88 ± 10 vs 88 ± 11; p = 0.8), but increased in those with an LVAD (87 ± 8 vs 95 ± 13; p0.001). Although the mean arterial BP (MAP) was negatively correlated with metabolic equivalents (METs) achieved during exercise, the association was not statistically significant (β = -0.1, p = 0.4). MAP correlated positively with METs achieved in patients with LVADs (MAP: β = 0.26, p = 0.04). Despite the abnormal response to exercise, patients with a TAH participated in physical therapy (median: 5 days; interquartile range [IQR] 4 to 7 days) and treadmill exercise (19 days; IQR: 13 to 35 days) early after device implantation, with increased exercise intensity and duration over time.During circulatory support with a TAH, the BP response to exercise was blunted. However, aerobic exercise training early after device implantation was found to be safe and feasible in a supervised setting.

Catalytic activity of sulfated zirconia was affected by both sulfur loading level and surface crystal phase. Incorporating silica or alumina into the catalyst system stabilized the tetragonal crystal phase and prolonged activity. Stabilized sulfated zirconia prepared with 20 wt.% alumina maintained catalytic activity for the isoparaffin alkylation reaction six times longer than pure sulfated zirconia. This performance enhancement has, thus far, not been disclosed in the literature. Reasons for the enhanced performance are hypothesized. UV–Raman spectroscopy was used to characterize the surface structure of sulfated zirconia. Samples displaying tetragonal reflections were catalytically active, while those displaying a surface monoclinic phase showed little activity. Examination of fresh, spent, and regenerated catalyst did not reveal any evidence for a phase transformation, indicating catalyst deactivation was most likely caused by the accumulation of hydrocarbon fragments on the surface.

Infrared spectra of pyridine adsorbed on zirconia and Pt–zirconia exhibited bands consistent with Lewis acid sites. Sulfated zirconia, after heating at 400°C, exhibited bands indicating about equal amounts of Lewis (L) and Bronsted (B) acid sites; the B/L ratio decreased with increasing reactivation temperature to become essentially zero after reactivation at 600°C. In contrast, both Pt and Fe/Mn promoted sulfated zirconia exhibited B/L ratios that increased slightly with increasing reactivation temperature. It is proposed that pyridine reacts with a Lewis acid site to produce an adsorbed “pyridone-type” surface species with the concurrent generation of a proton. The superior performance of the promoted sulfated zirconia catalyst is believed to arise from its ability to generate Bronsted acid sites.

Diffusion-weighted imaging (DWI) is an advanced magnetic resonance imaging technique, based on the analysis of thermallydependent movement of water molecules in the extracellular space. This method allows to examine pathological changes at the cellular level which are not visible on conventional magnetic resonance (MR). Apparent diffusion coefficient (ADC) is a mathematically calculated value indicating the diffusion. Reduced ADC value demonstrates a restricted diffusion while increased ADC value indicates a facilitated diffusion. Aim: The aim of this study was to assess changes in ADC values within normal appearing white matter (NAWM) and normal appearing gray matter (NAGM) in patients with MS before initiating the treatment with IFN-Beta and already in the course of treatment, in comparison with a control group. Material and Methods: The study comprised 84 patients divided into three groups: patients with MS before initiating the therapy with IFN-Beta (MS0, n = 28: 22 women, 6 men; average age: 28.8), patients with MS after at least one year of treatment with IFN-Beta (MS1, n = 28: 22 women, 6 men; average age: 30.2) and a control group of patients with no intracranial pathology (CG, n = 28: 20 women, 8 men; average age: 29.8). ADC was measured in 11 regions of interest (ROIs), as follows: 1, 2 − cerebellum at the level of dentate nuclei, 3 − pons, 4, 5 − thalamus, 6, 7 − caudate nuclei, 8, 9 − frontal white matter regions, 10, 11 − fronto-parietal white matter at the convexity. The results were compared between the groups. The study was performed using a 1.5T GE MRI scanner. DWI sequence was performed with the following parametres: b = 0 and b = 1000, TR=8000, TE=81.2, slice thickness = 4mm. Results: In the examined areas of brain, in ROIs: 8 and 9 the ADC values were statistically significantly higher in MS0 group in comparison with CG (p< 0.01). There were no significant differences in ADC values in ROIs: 8 and 9 between MS1 and CG. However, in ROI 6 the ADC values were significantly lower (p< 0.01), while in ROIs: 10 and 11 significantly higher (p< 0.01) in MS1 group in comaprison with CG. No other statistically significant differences were found between groups: MS0 and CG, MS1 and CG, as well as MS0 and MS1. Conclusions: Increased ADC values in NAWM of the frontal lobes in patients with MS before initiating the treatment with IFN-Beta may indicate early axonopathy, in the course of which diffusion is facilitated. Normalization of ADC values in this region after several months of treatment with IFN-Beta as well as decrease in ADC values in NAGM of right caudate nucleus may indicate a decrease of the diffusion and delay in the axonal damage as a result of immunomodulatory treatment.

The formation of nitrogen oxides (NOx) during the regeneration of fluid catalytic cracking (FCC) catalyst can be attributed to oxidation of nitrogen in coke. Thermal NOx does not occur to any significant extent at FCC regenerator temperature. NOx is primarily comprised of nitric oxide (NO) with only a small concentration of NO2 detected. Under typical FCC regenerator conditions, only 10% of the nitrogen in coke evolves from the regenerator as nitric oxide with flue gases. Our findings show that ∼90% of nitrogen in coke is converted to dinitrogen (N2) in the regenerator. The authors suggest that dinitrogen is a secondary product produced by the reduction of NO with carbon and/or carbon monoxide in the regenerator. NOx emissions are lower in controlled burn regenerators where exposure to excess oxygen is minimized. Two-stage regeneration was found to lower NOx emissions by conversion to N2 during recontacting of flue gases and catalyst in the dense bed.

The literature suggests that one of the key determinants of success at rugby union international competitions is the anthropometric profile of players. The Irish Rugby Football Union (IRFU) long-term player development (LTPD) model is a framework designed to guide the development of the tactical, physical, and psychological domains of sporting participation. In Ireland, the Train-to-Train stage of the IRFU model is a critical stage, whereby the next developmental progression would include the transition of players into professional academies. To date, no previously published studies have examined the anthropometric profile of Irish Schools' rugby union players at the Train-to-Train stage of the IRFU model. The anthropometric profile of 136 male adolescent rugby union players at the Train-to-Train stage of the IRFU model was assessed using total-body dual-energy x-ray absorptiometry. Significant differences in height, body mass, body fat percentage, fat mass, lean mass, and fat-free mass were observed between players assigned to the forward and back units, and for specific position categorizations within each unit. Direct logistic regression revealed that body mass was a statistically significant (p < 0.01) predictor of unit position classification, with an odds ratio of 2.35, indicating that the players with a higher body mass were twice as likely to be classified as forwards. The results of this study indicate that at the Train-to-Train stage of the IRFU model, forward and back units have distinctly different anthropometric profiles. Furthermore, anthropometric differentiation also exists within specific position categorizations within each of these playing units. Thus, anthropometric profiling should be carried out on a systematic and periodic basis, because this will allow for the evaluation of the effectiveness of the implementation strategies of the IRFU model on a national basis.

A series of titania-silica mixed oxides were prepared by co-precipitation and sol-gel methods. The mole fraction of titanium was varied from 0 to 1. The effects of preparation method and chemical composition on the physical properties and acidity profiles of mixed oxides were examined. While pure silica was non-acidic and titania contained only Lewis acid sites, Bronsted acidity was created by the Ti-O-Si interaction in the binary oxides. Samples containing a titania: silica mole ratio of 9 ∶ 1 possessed the largest amount of Bronsted acidity. The generation of acid sites and the stability of the oxide was a strong function of preparation method. With all preparation methods, higher calcination temperatures increased crystallinity and decreased the total number of acid sites.

A method of interconversion of dry sieve and laser light scattering particle size values has been developed for cracking catalysts. Values obtained by light scattering techniques were consistently larger than those obtained by dry sieve analysis. The differences were primarily due to lack of sphericity of the particles. The particle size distribution determined by light scattering techniques was based on an average particle diameter. Conversely, the sieve measured the smallest diameter of the particle which can pass through the opening. Microscopic examination of commercial cracking catalysts confirmed their nonuniformity. The sphericity of the catalyst particles decreased as particle size increased. Therefore, the divergence between the laser light scattering and dry sieving value became greater as the catalyst particle size increased.

An investigation of the factors which affect the ratio of combustion products in the flue gas from a catalytic cracking unit has been conducted. Units which process resids have been found to suffer feed throughput penalties as a result of high CO2 2 /CO ratios. This study describes the effect of contaminant metals (nickel, vanadium and iron) on the combustion of carbon in the regenerator. Effects of these metals were investigated since they are deposited on the catalyst during the catalytic cracking process. Typical zeolite cracking catalysts were used in this study. The metal activity for the production of carbon dioxide increases from iron nickel. Results of this investigation show that nickel catalyzes carbon directly to carbon dioxide. Therefore, the amount of active nickel should be minimized to prevent high CO 2 /CO ratios in the regenerator. In addition, the active catalytic species can be effectively passivated by antimony when nickel and antimony are allowed to interact under reducing conditions.

Catalytic reforming technologies and processes have been the subject of numerous discussions and reviews over the past 50 years.[1-8] Since the pioneering work of Vladimir Haensel and UOP[9] on platinum on alumina catalyst and platforming in the 1940s, catalytic reforming technology has evolved from semiregenerative, fixed-bed processes to the more energy efficient, highly reliable, low operating cost, continuous catalyst reforming units.[10] Typical process objectives are the upgrading of low octane naphthas to high octane gasoline blending components, production of aromatics and chemical feedstock, and production of hydrogen. Over the past five decades, numerous advancements have been made with respect to key reforming processes and in the development of high-performance catalysts. In the current environment of low-sulfur gasoline and ultralow-sulfur diesel regulations for reducing air pollutants,[11] catalytic reformers and in particular, continuous reformers have become indispensable as support to refiners’ plans for installation of enhanced processes for hydrotreating catalytic cracker feed, distillates, and catalytic cracker gasoline. Refiners will be relying on their catalytic reformers for reliable hydrogen supply for the various desulfurization processes required to achieve near-zero-sulfur gasoline and ultralow-sulfur diesel.

Publisher Summary The metals passivation is the process of mitigating the deleterious effects of contaminant metals, thereby improving the catalyst activity and/or selectivity to more desired products. Metals passivation is accomplished today in two ways: (1) metering the metals passivation agent, usually via the fresh feed, into the cracker where it deposits on the catalyst or (2) incorporating additives during manufacture into the catalyst formulation or into a separate carrier particle, which is blended with the catalyst. Passivation additives are normally referred to as “metal traps.” In the case of passivation of vanadium, the average life of the cracking catalyst particle is prolonged. With nickel, passivation decreases dehydrogenation activity. The refiner usually has several ways to utilize the benefits of reduced yields of hydrogen and coke achieved through metals passivation. One economically attractive option for many refiners has been to crack resid blended with the traditional gas oil feed.