1,089 research outputs found
Thermally induced behavior of the K-exchanged erionite. A further step in understanding the structural modifications of the erionite group upon heating
Fibrous erionite is a naturally occurring zeolite considered to be highly carcinogenic upon inhalation, even more than crocidolite. Since no iron is typically present in erionite, its toxicity has been attributed to ion-exchanged Fe participating in Fenton chemistry. Recently, a study aimed at investigating possible fiber inactivation routes surprisingly showed that, despite having completely occluded all available pores with K ions, the erionite-Na sample preserved the property to upload Fe (II) within the structure. In this work, the thermal behavior of the K-exchanged erionite-Na was investigated by TG/ DSC and in situ XRPD analyses in order to provide relevant information for modeling the thermally induced behavior of the erionite group. Rietveld refinement results evidenced a general trend of cell parameters and volume with temperature similar to that observed for erionite-K from Rome (Oregon, USA). However, the dependence of Tdehydrand Tbreakfrom Si/Si+Al ratio observed in zeolites (high Si content favours a lower Tdehydrand a higher Tbreak) is not observed, possibly due to the effect of the relevant amount of large K ions dispersed within the erionite cage, acting as reinforcing blocks for the framework. Heating produces a progressive emptying of the Ca sites, common effect previously observed in erionite samples showing different chemistry. In addition, K1 s.s. remains unchanged evidencing the absence of any “internal ion exchange” process, whereas s.s. at K2 increases in the range 438-573 K and then slowly decreases in the range 700-1218 K. Both Rietveld and DSC data suggest the motion of K ions from OW sites toward the walls of the erionite cavity during dehydration
Effects of oral citicoline in perimetric glaucoma defects
Abstract: Purpose: to study the neuroprotective effect of oral citicoline (CT) in patients with primary
open-angle glaucoma (POAG). Methods: this study recruits 110 patients with stage IV POAG and
well-controlled intraocular pressure (IOP). Enrollees were randomly allocated in two groups: therapy
group (TG) or control group (CG). Subjects in TG were treated with citicoline 500 mg / die for 4
months. The treatment period was followed by a wash-out phase of 2 months. At the end of the washout phase, subjects in TG resumed CT in the same fashion. Both groups were treated with pressurelowering medications. Each subject was evaluated with standard automated perimetry (SAP) at
baseline, and then again 12, 24, and 36 months after enrollment.
Results: TG showed a statistically significant improvement in MD values at 12 months (∆ = 21%) and
T24 (∆ = 35%), and gradual improvements of the stage, up to the 3rd stage with localized defects after
36 months of therapy. Conversely, in CG, both the MD and PSD indices continued to deteriorate
throughout the duration of the study.
Conclusion: long-term daily treatment with citicoline might have a neuroprotective effect. Patients
treated with oral citicoline showed an improvement in perimetric indices. Additional studies with
larger samples and longer follow-ups are needed to confirm these results
Online assessment of negotiation skills through 3D role play simulation
The lack of standardised technological tools to assess psychological characteristics allows traditional tests to be still widely used, though these tests require double processing and expensive procedures. ENACT is both a serious game for a standardised assessment of the user negotiation skills and an Intelligent Tutoring System, which makes use of the data collected during the interaction in order to generate a tailored environment for the user to experience and improve their skills and be guided through learning
Optical coherence tomography of retinal and choroidal layers in patients with familial hypercholesterolaemia treated with lipoprotein apheresis
PURPOSE: Detect and quantify morpho-functional alterations of the retina and choroid in patients affected by familial hypercholesterolemia (FH) treated with lipoprotein apheresis (LA) using optic coherence tomography (OCT) and optic coherence tomography-angriography (OCTA). DESIGN: Observational study. SUBJECTS: To be diagnosed: A group of 20 patients (40 eyes) being clinically and genetically diagnosed as FH and under treatment (FH-Group)", for at least 2 years, was compared to a control group of 20 healthy subjects (40 eyes), with a normal lipid profile and no ocular disease (CT-Group). METHODS: Participants were studied with the slit lamp, binocular indirect fundoscopy, OCT and OCTA. MAIN OUTCOME MEASURES: Best corrected visual acuity (BVCA), spherical equivalent (SE), intraocular pressure (IOP), central macular thickness (CMT), choroidal thickness (CHT), retinal nerve fiber layer in four quadrants (RNFL (Superior = Sup; Inferior = Inf; Nasal = Nas Temporal = Temp), and the mean value across the four quadrants (RNFL G), foveal avascular zone (FAZ) and vascular density (VD). RESULTS: FH subjects had smaller RNFL superiorly (108 ± 19,38 μm OD/111 ± 16,56 μm OS FH-Group vs 127 ± 7,42 μm OD/129 ± 14,64 μm OS CT-Group; P < 0,001 for both OD and OS) and inferiorly (108 ± 23,58 μm OD/115 ± 17,33 μm OS FH-Group vs 128 ± 18,15 μm OD/133 ± 17,38 μm OS CT-Group; P = 0,002 OD; P = 0,001 OS). G RNFL was consequently smaller (93 ± 12,94 μm OD/94 ± 10,49 μm OS FH-Group vs 101 ± 9,01 μm OD/101 ± 10,20 μm OS CT-Group; P = 0,03 OD; P = 0,02 OS). FH subjects had a larger FAZ (0,31 ± 0,08 mm2 OD/0,33 ± 0,10 mm2 in OS FH-Group vs 0,21 ± 0,05 mm2 OD/0,21 ± 0,07 mm2 OS CT-Group; P < 0,001 OD; P = 0,002 OS). CONCLUSIONS: Early signs of retinal vessel damage in FH patients can be detected and quantified with OCT and OCTA
Alesco and Mark Resources: Cross-Border Tax Arbitrage, Economic Reality, and Anti-Avoidance Rules in New Zealand and Canada
This essay compares the role given to the concept of economic reality in New Zealand and Canadian cross-border tax arbitrage decisions, particularly Alesco and Mark Resources. Alesco and Mark Resources both address the problem of drawing the line between acceptable tax mitigation and unacceptable avoidance, and adopt economic substance as a key indicator of where this line lies. This essay considers how the concept of economic reality pervades these cases and evaluates the influence of legislative and judicial context to the significance afforded to the concept of economic reality in the two decisions, as well as reviewing how the economic realities jurisprudence has evolved following these cases
Double hit: mantle cell lymphoma associated with squamous cell carcinoma or chalazion? A case report
A few cases of ocular adnexal neoformations related with MCL have been reported in the literature. We present a rare case of tumour duplicity: mantle cell lymphomas (MCL) associated with squamous cell carcinoma (SCC) localised at the level of the ocular adnexa, on left upper eye lid mass since two years of 18 mounth duration in a 57-year-old man who had previously been diagnosed with stage IV MCL for 14 months. The patient had been treated according to the R-DHAP scheme for 4 cycles, in anticipation of a possible autologous HSC transplant, which was not carried out due to a positive diagnosis at the end-of-cycle osteomedullary biopsy (BOM) check. Ophthalmological examination was performed, and afther surgical removal histological examination proved to be squamous cell carcinoma (SCC). The aim of this case report is to decode the signs, symptoms and factors associated with the formation, that appear to be a chalazion, at an early stage in order to prevent the overgrowth of the mass that could invade the surrounding tissues by infiltrating them, as well as negative aesthetic outcomes of the surgery due to the excessive size of the mass, which could compromise the patient's quality of life
Disconnections in personal neglect
Personal neglect is a disorder in the perception and representation of the body that causes the patients to behave as if the contralesional side of their body does not exist. This clinical condition has not been adequately investigated in the past as it has been considered a symptom of unilateral spatial neglect, which has mainly been studied with reference to extrapersonal space. Only a few studies with small samples have investigated the neuroanatomical correlates of personal neglect, and these have mainly focused on discrete cortical lesions and modular accounts, as well as being based on the hypothesis that this disorder is associated with somatosensory and spatial deficits. In the present study, we tested the novel hypothesis that personal neglect may be associated not only with discrete cortical and subcortical lesions, but also with disconnections of white matter tracts. We performed an advanced lesion analyses in a large sample of 104 right hemisphere damaged patients, 72 of whom were suffering from personal neglect. Results from the analyses of the grey and white matter were controlled for co-occurrent clinical variables such as extrapersonal neglect, anosognosia for hemiplegia and motor deficits, along with other lesion-related variables such as lesion size and the interval from the lesion onset to neuroimaging recordings. Our results reveal that personal neglect is associated with lesions in a medial network which involves the temporal cortex (Heschl's gyrus), the ventro-lateral nuclei of the thalamus and the fornix. This suggests that personal neglect involves a convergence between sensorimotor processes, spatial representation and the processing of self-referred information (episodic memory)
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