We have synthesized pure TeO2 glass and glasses in the systems xZnO−(1−x)TeO2 (0≤x≤0.50) and yAl2O3−(1−y)TeO2 (0≤y≤0.03) by melting in Pt crucibles, and measured their glass transition temperature ...(Tg), density (ρ) and Raman spectra to correlate glass properties with structure. For pure TeO2 glass, synthesized using our newly developed intermittent quenching technique, we find onset- and midpoint-Tg at 301.1 and 306.7°C and ρ=5.62g/cm3, in clear disagreement with TeO2 glass melted in alumina crucible for which we find Tg≈380°C and ρ=4.86g/cm3. This latter method, used frequently in the literature, was shown by Raman spectroscopy to introduce Al2O3 in the tellurite matrix which becomes cross-linked by Te-O-Al bridges, resulting in the increase of Tg and decrease of ρ. Raman spectroscopy showed also that doping TeO2 with ZnO or Al2O3 causes the progressive conversion of TeO4 trigonal bipyramids to TeO3+1 polyhedra with two terminal oxygens, and then to TeO3 trigonal pyramids with three terminal oxygens. This structural transformation is reflected in the composition dependence of the volume per mole TeO2 evaluated from density data. The ZnO-dependence of this parameter is described by two linear parts with an inflection point at x=0.25, which indicates an increasing rate of forming terminal TeO bonds at higher ZnO contents. The Tg was found to increase with ZnO and Al2O3 contents and this was attributed to the glass-forming ability of both oxides, while density was found to decrease due mainly to replacement of the heavier TeO2 by the lighter ZnO and Al2O3. The results of this study are discussed with reference to previous works on TeO2 and zinc-tellurite glasses.
•Pure TeO2 glass was made by a newly developed intermittent quenching technique.•Tg and density values were determined for the pure TeO2 glass.•Zinc-tellurite and alumina-tellurite glasses were made by melting in Pt crucibles.•Tg increases and density decreases as ZnO or Al2O3 is added to the TeO2 matrix.•The tellurite structure of the studied glasses was probed by Raman spectroscopy.
An overview on pure autonomic failure Pavy-Le Traon, A.; Foubert-Samier, A.; Fabbri, M.
Revue neurologique,
January-February 2024, 2024 Jan-Feb, 2024-01-00, 20240101, 2024-01-01, Letnik:
180, Številka:
1-2
Journal Article
Recenzirano
Pure autonomic failure (PAF) is a neurodegenerative disease affecting the sympathetic component of the autonomic nervous system and presenting as orthostatic hypotension (OH). It is a rare, sporadic ...disease of adults. Although OH is the primary symptom, the autonomic dysfunction may be more generalised, leading to genitourinary and intestinal dysfunction and sweating disorders. Autonomic symptoms in PAF may be similar to those observed in other autonomic neuropathies that need to be ruled out. PAF belongs to the group of α synucleinopathies and is characterised by predominant peripheral deposition of α-synuclein in autonomic ganglia and nerves. However, in a significant number of cases, PAF may convert into another synucleinopathy with central nervous system involvement with varying prognosis: Parkinson's disease (PD), multiple system atrophy (MSA), or dementia with Lewy bodies (DLB). The clinical features, the main differential diagnoses, the risk factors for “phenoconversion” to another synucleinopathy as well as an overview of treatment will be discussed.
•Several ML models are utilized to estimate MMP for pure CO2 flooding.•Diverse data with various conditions and independent parameters are included.•Sensitivity analysis and the impact of parameters ...are investigated.•ML models are more effective and reliable in predicting the MMP of pure CO2 injection.
CO2 injection for enhanced oil recovery (EOR) is widely recognized as an efficient technique for carbon capture, utilization, and storage (CCUS). This operation has a significant impact on various technical parameters, emphasizing the need to carefully consider and select the optimum approach. Among these factors, the minimum miscible pressure (MMP) plays a crucial role in determining the effectiveness and performance of CO2 injection. Therefore, this study aims to assess the reliability of machine learning (ML) in predicting the MMP of pure CO2 and examine the influence of different independent parameters. To achieve this, five ML methods were employed to predict the pure CO2 MMP, and the results were compared to statistical evaluations based on empirical correlations. In addition, three types of data with different functional input parameters were used in this research. Two types of data were obtained from existing literature, while the third category was collected from the thesis and PVT reports for specific Iraqi oil fields. The ML models were constructed by splitting the dataset into 20% for testing and 80% for training using Python programming. The significance of this study lies in its ability to identify the most efficient approach for forecasting MMP. The results of this work revealed that the K-nearest neighbors (KNN) model indicated the best statistical evaluation among the ML learning algorithms for two types of data (2) and (3) in predicting the MMP for pure CO2 flooding. This was evidenced by the lowest mean square error and the highest coefficient of determination. Additionally, the findings indicated that the support vector regression (SVR) method is an effective technique for smaller datasets. Moreover, the sensitivity analysis and assessment of the relative impacts of various input parameters revealed that the prediction of MMP is most sensitive to the composition of the injected gas and temperature, accounting for 46% and 28.5% of the variation, respectively. Finally, the presented ML models indicate exceptional accuracy, speed, adaptability in handling diverse conditions, and cost-effectiveness when compared to conventional approaches. These results verify the ability of ML models to provide high-quality predictions.
Abstract
Objective: To determine if a smartphone application could be used as a calibrated screening audiometer with real-time noise monitoring for school screening using automated test sequences. ...Design: The investigation comprised three studies. Study 1 evaluated calibration accuracy across four Samsung S5301 smartphones (Android v4.0.4) using commercial Sennheiser HD202 headphones. Study 2 involved referencing smartphone microphone sensitivity to narrowband noise intensity as measured in octave bands by a sound-level meter between 30 and 75 dB SPL (5 dB increments). Study 3 compared screening outcomes of smartphone based and conventional hearing screening. Study sample: Study 2: 15 normal-hearing subjects (age range, 18-22 years; all female). Study 3: 162 children (324 ears) aged 5 to 7 years. Results: Smartphone calibration at 20, 30, and 40 dB was within 1 dB of recommended reference equivalent thresholds levels. Microphone calibration for noise monitoring had maximum variability across phones of 0.9, 0.6, and 2.9 dB at 1, 2, and 4 kHz, respectively, from reference intensities (30 to 75 dB SPL). Screening outcomes demonstrated no significant difference between smartphone and conventional audiometry with an overall referral rate of 4.3% and 3.7%, respectively. Conclusions: The newly developed smartphone application can be accurately calibrated for audiometry with valid real-time noise monitoring, and clinical results are comparable to conventional screening.
Pure alexia is an acquired reading disorder, typically due to a left occipito-temporal lesion affecting the Visual Word Form Area (VWFA). It is unclear whether the VWFA acts as a unique bottleneck ...for reading, or whether alternative routes are available for recovery. Here, we address this issue through the single-case longitudinal study of a neuroscientist who experienced pure alexia and participated in 17 behavioral, 9 anatomical, and 9 fMRI assessment sessions over a period of two years. The origin of the impairment was assigned to a small left fusiform lesion, accompanied by a loss of VWFA responsivity and by the degeneracy of the associated white matter pathways. fMRI experiments allowed us to image longitudinally the visual perception of words, as compared to other classes of stimuli, as well as the mechanisms of letter-by-letter reading. The progressive improvement of reading was not associated with the re-emergence of a new area selective to words, but with increasing responses in spared occipital cortex posterior to the lesion and in contralateral right occipital cortex. Those regions showed a non-specific increase of activations over time and an increase in functional correlation with distant language areas. Those results confirm the existence of an alternative occipital route for reading, bypassing the VWFA, but they also point to its key limitation: the patient remained a slow letter-by-letter reader, thus supporting the critical importance of the VWFA for the efficient parallel recognition of written words.
•Pure alexia is a selective acquired impairment of visual word recognition.•It stems from left temporal lesions affecting the Visual Word Form Area (VWFA).•An alexic patient was scanned 9 times over a period of two years.•We study the mechanisms of reading improvement through letter-by-letter reading.•We demonstrate the role of an alternative occipital route bypassing the VWFA.
Pure‐red perovskite LEDs (PeLEDs) based on CsPb(Br/I)3 nanocrystals (NCs) usually suffer from a compromise in emission efficiency and spectral stability on account of the surface halide ...vacancies‐induced nonradiative recombination loss, halide phase segregation, and self‐doping effect. Herein, a “halide‐equivalent” anion of benzenesulfonate (BS–) is introduced into CsPb(Br/I)3 NCs as multifunctional additive to simultaneously address the above challenging issues. Joint experiment‐theory characterizations reveal that the BS– can not only passivate the uncoordinated Pb2+‐related defects at the surface of NCs, but also increase the formation energy of halide vacancies. Moreover, because of the strong electron‐withdrawing property of sulfonate group, electrons are expected to transfer from the CsPb(Br/I)3 NC to BS– for reducing the self‐doping effect and altering the n‐type behavior of CsPb(Br/I)3 NCs to near ambipolarity. Eventually, synergistic boost in device performance is achieved for pure‐red PeLEDs with CIE coordinates of (0.70, 0.30) and a champion external quantum efficiency of 23.5%, which is one of the best value among the ever‐reported red PeLEDs approaching to the Rec. 2020 red primary color. Moreover, the BS–‐modified PeLED exhibits negligible wavelength shift under different operating voltages. This strategy paves an efficient way for improving the efficiency and stability of pure‐red PeLEDs.
Pure‐red PeLEDs based on CsPb(Br/I)3 NCs that simultaneously offer high brightness and high efficiency are demonstrated via reducing self‐doping effect, suppressing phase separation, and passivating uncoordinated Pb2+ related defects by using a multifunctional “halide‐equivalent” benzenesulfonate anion passivation technique. The pure‐red PeLEDs exhibit a high brightness of 1510 cd m−2, a peak external quantum efficiency of 23.5%, and decent electroluminescence spectral stability.
Pial arterial malformations (PAMs) are rare vascular lesions consisting of dilated tortuous arteries without venous drainage. Current PAM understanding is limited by the lesion's rarity, limited ...anatomopathological studies, and frequent misclassifications.
A 23-year-old male experienced two spontaneous subarachnoid hemorrhages (SAHs) over 6 months with initially unremarkable diagnostic cerebral angiograms. Magnetic resonance imaging (MRI) and angiography after the second SAH revealed a small perimesencephalic ovoid lesion within the left crural cistern, between the left superior and posterior cerebral arteries, appearing to be an exophytic cavernoma, a thrombosed aneurysm, or a hemorrhagic tumor. Microsurgical resection was achieved with a pterional craniotomy and anterior clinoidectomy. The resected lesion was characteristic of a pure PAM arising from superior cerebellar arterial branches.
Small pure PAMs can be deceitfully dynamic lesions causing episodes of hemorrhage, complete thrombosis (angiographically occult), recanalization, and rehemorrhage. Small thrombosed vascular malformations or aneurysms should be included in differential diagnoses of angiographically occult SAH. MRI can be diagnostic, but the true angioarchitecture can only be elucidated with microneurosurgery. The only definitive cure is removal. The microneurosurgical strategy should account for worst-case scenarios, provide adequate skull base exposures, and include bypass revascularization options when thrombosed aneurysms are encountered.
A simplified multi-drop coating method that improves the grain size and film quality is introduced to construct and stabilize a pure α-phase formamidinium (FA) lead iodide ((NH2)2CHPbI3, FAPbI3) ...perovskite layer. The developed method is then extended to fabricate an FA and methylammonium (MA) (FA/MA) mixed cation perovskite film under ambient conditions. The acquired FAPbI3 film contains micron-sized large grains with preferred 111 orientation, which dramatically reduced the grain boundary area and the associated charge recombination to provide high short-circuit current densities and power conversion efficiencies (PCE) of up to 23.86 mA cm−2 and 17.66%, respectively. The open-circuit voltage of the device and the efficiency are further improved after extending this method to the FA/MA mixed perovskite film. Finally, the highest PCE reached 19.3%.
A pure α-phase FAPbI3 perovskite film with micron-sized large crystal grains has been constructed via a simplified multi-drop coating method. Display omitted
•A simplified multi-drop coating method was developed for PAPbI3 fabrication.•Reaction kinetic of FAI and PbI2, and morphology of FAPbI3 film were controlled.•Pure α-phase FAPbI3 perovskite film with large crystal grains was constructed.•Perovskite solar cells with power conversion efficiency 19.3% are fabricated.
Within a period of three years, we identified 13 patients in whom pure red-cell aplasia developed during treatment with recombinant human erythropoietin (epoetin). We investigated whether there was ...an immunologic basis for the anemia in these patients.
Serum samples from the 13 patients with pure red-cell aplasia were tested for neutralizing antibodies that could inhibit erythroid-colony formation by normal bone marrow cells in vitro. The presence of antierythropoietin antibodies was identified by means of binding assays with the use of radiolabeled intact, deglycosylated, or denatured epoetin.
Serum from all 13 patients blocked the formation of erythroid colonies by normal bone marrow cells. The inhibition was reversed by epoetin. Antibodies from 12 of the 13 patients bound only conformational epitopes in the protein moiety of epoetin; serum from the remaining patient bound to both conformational and linear epitopes in erythropoietin. In all the patients, the antibody titer slowly decreased after the discontinuation of treatment with epoetin.
Neutralizing antierythropoietin antibodies and pure red-cell aplasia can develop in patients with the anemia of chronic renal failure during treatment with epoetin.
Summary
Pure red cell aplasia (PRCA) is a syndrome characterized by a severe normocytic anaemia, reticulocytopenia, and absence of erythroblasts from an otherwise normal bone marrow. Primary PRCA, or ...secondary PRCA which has not responded to treatment of the underlying disease, is treated as an immunologically‐mediated disease. Although vigorous immunosuppressive treatments induce and maintain remissions in a majority of patients, they carry an increased risk of serious complications. Corticosteroids were used in the treatment of PRCA and this has been considered the treatment of first choice although relapse is not uncommon. Cyclosporine A (CsA) has become established as one of the leading drugs for treatment of PRCA. However, common concerns have been the number of patients treated with CsA who achieve sustained remissions and the number that relapse. This article reviews the current status of CsA therapy and compares it to other treatments for diverse PRCAs.
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