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Power-to-Gas (P2G) is considered as a promising energy storage technology in a long-time horizon. The rapid growth in the share of intermittent renewables in the energy mix is driving forward research and development in large-scale energy storage. This paper presents a feasibility analysis of a power-to-gas system in terms of various operating points and capacities. The analysis was performed using a system model, which features a solid oxide electrolyzer (SOE), a CO2 separation unit, and a methanation reactor as the key components. For the purposes of the techno-economic assessment (TEA) of the system, the CAPEX/OPEX estimation was performed and the cost structure defined. The model proposed in the study enables system-level optimization, including technical and economic criteria, considering two nominal scales: 10 kW and 40 GW, which corresponds to the nominal capacity of SOE in each case. According to the study, in an SOE-based P2G system, the cost of synthetic natural gas (SNG) production will fall by 15-21% by 2030 and 29-37% by 2050. SNG production would cost 3.15-3.75 EUR2023/kgSNG in 2030 and 2.6-3.0 EUR2023/kgSNG in 2050 for systems with SOE power >10 MW. Generally, product cost reductions occur as a result of material development and large-scale production, which influences the system's CAPEX. According to the research, the technology will break even by 2050. The large-scale power-to-gas system with a total of 40 GW installed capacity delivers a product price of 2.4 EUR2023/kgSNG with the average conversion efficiency of 68%.
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Gas Natural , Óxidos , Estudios de Factibilidad , Electrólisis , Fluocinolona AcetonidaRESUMEN
PURPOSE: Adipokines belong to a group of molecules mostly produced by adipose tissue. Abnormalities in the secretion of several adipokines have already implicated to play a pathogenic role in systemic sclerosis (SSc). However, the possible role of numerous molecules still needs to be clarified. The aim of the study was to determine whether the altered level of selected circulating adipokines might correlate with the intensity of fibrosis and vasculopathy in the course of SSc. MATERIALS AND METHODS: Serum concentrations of chemerin, adipsin, retinol-binding protein 4, apelin, visfatin, omentin-1, and vaspin were determined with ELISA in the sera of patients with SSc (n â= â55) and healthy controls (n â= â25). RESULTS: The serum concentration of adipsin (p â= â0.03) and visfatin (p â= â0.04) was significantly increased and the level of retinol-binding protein 4 (p â= â0.03) was decreased in diffuse compared to limited cutaneous SSc. Moreover, serum adipsin level correlated positively with the intensity of skin fibrosis measured with the modified Rodnan skin score (r â= â0.31, p â= â0.02) and was significantly higher in patients with pulmonary arterial hypertension than in those without the condition (p â= â0.03). The concentrations of adipsin (p â= â0.01) and visfatin (p â= â0.04) were significantly increased and the level of apelin (p â= â0.02) was decreased in patients with active digital ulcerations compared to individuals without this complication. CONCLUSION: Adipsin may be considered a pivotal protein in the development of both fibrosis and impaired microcirculation. Its abnormal concentration reflects the intensity of skin thickening and the presence of pulmonary arterial hypertension. Adipsin, visfatin, and apelin are adipose tissue-derived molecules associated with digital vasculopathy.
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Hipertensión Arterial Pulmonar , Esclerodermia Sistémica , Enfermedades Vasculares , Humanos , Adipoquinas/metabolismo , Factor D del Complemento/metabolismo , Apelina/metabolismo , Nicotinamida Fosforribosiltransferasa/metabolismo , Microcirculación , Fibrosis , Proteínas de Unión al RetinolRESUMEN
The A-site cation-ordered GdBa0.5Sr0.5Co2-xCuxO5+δ (GBSCC) double perovskites are evaluated regarding the development of high-performance oxygen electrodes for reversible solid oxide cells (rSOCs). The aims are to maximally decrease the content of toxic and expensive cobalt by substitution with copper while at the same time improving or maintaining the required thermomechanical and electrocatalytic properties. Studies reveal that compositions with 1 ≤ x ≤ 1.15 are particularly interesting. Their thermal and chemical expansions are decreased, and sufficient transport properties are observed. Complementary density functional theory calculations give deeper insight into oxygen defect formation in the considered materials. Chemical compatibility with La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) and Ce0.9Gd0.1O2-δ (GDC) solid electrolytes is evaluated. It is documented that the GdBa0.5Sr0.5Co0.9Cu1.1O5+δ oxygen electrode enables obtaining very low electrode polarization resistance (Rp) values of 0.017 Ω cm2 at 850 °C as well as 0.111 Ω cm2 at 700 °C, which is lower in comparison to that of GdBa0.5Sr0.5CoCuO5+δ (respectively, 0.026 and 0.204 Ω cm2). Systematic distribution of relaxation times analyses allows studies of the electrocatalytic activity and distinguishing elementary steps of the electrochemical reaction at different temperatures. The rate-limiting process is found to be oxygen atom reduction, while the charge transfer at the electrode/electrolyte interface is significantly better with LSGM. The studies also allow elaborating on the catalytic role of the Ag current collector as compared with Pt. The electrodes manufactured using materials with x = 1 and 1.1 permit reaching high power outputs, exceeding 1240 mW cm-2 at 850 °C and 1060 mW cm-2 at 800 °C, for the LSGM-supported cells, which can also work in the electrolysis mode.
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Cu-content La1-xSrxNi1-yCuyO3-δ perovskites with A-site strontium doping have been tuned as cobalt-free cathode materials for high-performance anode-supported SOFCs, working at an intermediate-temperature range. All obtained oxides belong to the R-3c trigonal system, and phase transitions from the R-3c space group to a Pm-3m simple perovskite have been observed by HT-XRD studies. The substitution of lanthanum with strontium lowers the phase transition temperature, while increasing the thermal expansion coefficient (TEC) and oxygen non-stoichiometry δ of the studied materials. The thermal expansion is anisotropic, and TEC values are similar to commonly used solid electrolytes (e.g., 14.1 × 10-6 K-1 for La0.95Sr0.05Ni0.5Cu0.5O3-δ). The oxygen content of investigated compounds has been determined as a function of temperature. All studied materials are chemically compatible with GDC-10 but react with LSGM and 8YSZ electrolytes. The anode-supported SOFC with a La0.95Sr0.05Ni0.5Cu0.5O3-δ cathode presents an excellent power density of 445 mW·cm-2 at 650 °C in humidified H2. The results indicate that La1-xSrxNi1-yCuyO3-δ perovskites with strontium doping at the A-site can be qualified as promising cathode candidates for anode-supported SOFCs, yielding promising electrochemical performance in the intermediate-temperature range.
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Lipocalin-2 and visfatin are proinflammatory adipokines involved in the regulation of glucose homeostasis. Their role has been described in numerous inflammatory skin diseases such as atopic dermatitis and psoriasis. Recently, an increased prevalence of metabolic abnormalities has been reported in patients with alopecia areata. The aim of the study is to determine the serum levels of lipocalin-2 and visfatin in patients with alopecia areata in comparison with healthy controls. Moreover, the serum levels of total cholesterol, low-density lipoprotein cholesterol (LDL-cholesterol), high-density lipoprotein cholesterol (HDL-cholesterol), triglycerides, fasting glucose, insulin, c-peptide, and homeostasis model assessment for insulin resistance (HOMA-IR) were evaluated. Fifty-two patients with alopecia areata and 17 control subjects were enrolled in the study. The serum levels of lipocalin-2 [mean ± standard deviation, SD: 224.55 ± 53.58 ng/ml vs. 188.64 ± 44.75, p = 0.01], insulin [median (interquartile range, IQR): 6.85 (4.7-9.8) µIU/ml vs. 4.5 (3.5-6.6), p<0.05], c-peptide [median (IQR): 1.63 (1.23-2.36) ng/ml vs. 1.37 (1.1-1.58), p<0.05)], and HOMA-IR [median (IQR): 1.44 (0.98-2.15) vs. 0.92 (0.79-1.44), p<0.05) were significantly higher in patients with alopecia areata compared to the controls. The serum concentration of insulin and HOMA-IR correlated with the number of hair loss episodes (r = 0.300, p<0.05 and r = 0.322, p<0.05, respectively). Moreover, a positive correlation occurred between insulin, HOMA-IR, c-peptide and BMI (r = 0.436, p <0.05; r = 0.384, p<0.05 and r = 0.450, p<0.05, respectively). In conclusion, lipocalin-2 and insulin may serve as biomarkers for alopecia areata. Further studies are needed to evaluate the role of insulin as a prognostic factor in alopecia areata.
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Alopecia Areata , Resistencia a la Insulina , Insulina , Lipocalina 2 , Alopecia Areata/diagnóstico , Biomarcadores/sangre , Péptido C , HDL-Colesterol , Glucosa , Humanos , Insulina/sangre , Lipocalina 2/sangre , Nicotinamida FosforribosiltransferasaRESUMEN
BACKGROUND: Alopecia areata (AA) is an autoimmune form of hair loss, which may affect any hair-bearing area. It has been suggested that AA is associated with an increased risk of metabolic and cardiovascular comorbidities. AIM: To evaluate the early predictors of cardiovascular disease [endothelial function (EF) and arterial stiffness (AS)] in patients with AA without prior cardiovascular disease, and compare with healthy controls (HCs). METHODS: In total, 52 patients with AA (38 women and 14 men; mean age 41 years, range 30-52 years) and 34 HCs, matched for age, sex and body mass index, were enrolled in the study. EF, expressed as reactive hyperaemia index (RHI), and AS, identified by augmentation index at 75 beats/min (AI@75) were assessed with the use of the Endo-PAT 2000 device. Endothelial dysfunction (ED) was defined as RHI value ≤1.67. RESULTS: ED was observed in 22 of 52 patients with AA (42%) and in 4 of 34 HCs (12%) (P < 0.01). Moreover, mean RHI was lower in patients with AA compared with HCs (1.90 ± 0.31 vs. 2.11 ± 0.45; P = 0.03). There was no significant difference in AI@75 between patients with AA and HCs. CONCLUSIONS: Patients with AA show abnormalities in early predictors of cardiovascular diseases. Regular cardiovascular screening might be appropriate for patients with AA.
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Alopecia Areata , Enfermedades Cardiovasculares , Enfermedades Vasculares , Adulto , Alopecia Areata/complicaciones , Enfermedades Cardiovasculares/complicaciones , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Vasculares/complicacionesRESUMEN
Dermatomyositis is a chronic inflammatory disease involving the skin and muscles. It most commonly occurs in adults with preponderance in females, but pediatric occurrence is also possible. The risk of malignancy in adult patients with dermatomyositis was reported to be 4.66-fold higher compared to that in the general population. A significantly increased risk of malignancy was reported within the first 12 months following the diagnosis of dermatomyositis (standardized incidence ratio equaled 17). One of the characteristic laboratory findings associated with dermatomyositis is the presence of circulating autoantibodies which are classified into two subgroups: myositis-specific and myositis-associated autoantibodies. It was shown that specific types of antibodies might be associated with an increased risk of malignancy. Current literature data indicate that the strongest correlation with malignant diseases was reported in anti-TIF1-γ-positive patients who were at a 9.37-fold higher risk of cancer. A 3.68-fold increase in the risk of cancer was also reported among patients with anti-NXP2 antibodies. Malignant diseases were reported in 14-57% of patients with anti-SAE antibodies. The presence of other autoantibodies may also be associated with an increased risk of malignancy. These data indicate that patients with circulating anti-TIF1-γ, anti-NXP2, and anti-SAE should be very closely monitored for dermatomyositis-associated malignant comorbidities. The aim of this review is to summarize the current data regarding the link between malignancy and the presence of specific antibodies in patients with dermatomyositis.
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Dermatomiositis , Miositis , Neoplasias , Adulto , Autoanticuerpos , Biomarcadores , Niño , Femenino , Humanos , Neoplasias/epidemiologíaRESUMEN
Alopecia areata is an autoimmune, inflammatory form of non-scarring hair loss that may affect any hair-bearing area. Recently, an increased risk of cardiovascular disorders has been described in patients with alopecia areata. The aim of the study was to evaluate the serum concentrations of proinflammatory proteins associated with atherosclerosis (chemokine C-C motif ligand 4; CCL4, chemokine C-C motif ligand 7, CCL7; and sortilin, SORT1), and cardiovascular risk (myeloperoxidase, MPO; interleukin 1 receptor-like 1, IL1RL1; and growth differentiation factor 15, GDF15) in patients with alopecia areata without symptoms or prior cardiovascular disease in comparison with healthy controls. Sixty otherwise healthy patients with alopecia areata and twenty control subjects matched for age, gender, and body mass index (BMI) were enrolled in the study. No significant differences in the serum levels of MPO, IL1RL1, CCL4, CCL7, SORT1, and GDF15 were detected between patients with alopecia areata and healthy controls. A positive correlation was found between the serum concentration of CCL7 and the severity of alopecia areata (r = 0.281, p = 0.03), while GDF15 correlated with age at the disease onset (r = 0.509, p < 0.0001). The results of the present study suggest that the severity of alopecia areata may be associated with an increased risk of atherosclerosis.
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Scleroderma (morphea) en coup de sabre is a localized subtype restricted to the frontoparietal region of the head. Current treatment paradigms rely on low levels of evidence, primarily case reports and case series-supported by expert opinions. The aim of this article was to systematically analyze current data related to the treatment of localized scleroderma en coup de sabre. The databases Scopus, PubMed, and EBSCO were searched for all reports discussing the treatment of localized scleroderma en coup de sabre. The keywords en coup de sabre, "facial linear scleroderma", and "morphea linearis", combined with "treatment" or "therapy" were used as search terms. A total of 34 articles analyzed treatment outcomes for patients with localized scleroderma en coup de sabre including 4 retrospective cohort studies, 2 prospective cohort studies, 4 case series, and 24 case reports, representing a total of 69 patients (38 children and 31 adults). Methotrexate was the most commonly investigated treatment (26 patients) with a highest response rate (26/26, 100%). Other treatments included systemic glucocorticosteroids (nine patients), followed by UVA1 (four patients), mycophenolate mofetil (two patients), hydroxychloroquine (five patients), abatacept (two patients), tocilizumab (three patients), cyclosporine (one patient), interferon gamma (one patient), PUVA therapy (two patients), NB-UVB therapy (one patient), and pulsed dye laser (one patient). Reconstructive and surgery treatment was successfully used for lesions with settled disease activity to improve the cosmetic aspect of the lesions. Conclusion: methotrexate is the most often-studied treatment and reported good clinical outcomes in children and adults with localized scleroderma en coup de sabre.
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The effects of A-site substitutions on the interstitial oxygen formation energy and the migration energy in layered A2-xA'xNiO4+δ (A = selected lanthanides, A' = Ba, Sr, Ca) are investigated by first principles calculations. The interstitial oxygen formation energy is negative, in the range of -4.81 eV to -3.45 eV, strongly supporting easiness of formation of the interstitial oxygen defects in the (A,A')O rock salt plane. The Pr2NiO4+δ compound shows the lowest formation energy, indicating the highest amount of interstitial oxygen. Doping with alkaline earth cations (A') increases the formation energy of the interstitial oxygen, which prefers to be located far away from the dopants. Nevertheless, Ca seems to be the best choice, due to relatively low formation energy. Calculations for the four kinds of diffusion paths allow it to be predicted that the oxygen transport in A2-xA'xNiO4+δ is governed by the interstitialcy mechanism in the ab plane, because of the significantly lower energy barriers for this mechanism. An interesting finding is achieved for A2NiO4+δ (A = Pr, Nd, Sm), for which the energy barriers for the interstitialcy transport are negative (-0.47 eV, -0.33 eV and -0.02 eV, respectively), implying that the transition state is more stable than the assumed initial state. A new structural configuration is proposed in this work, with the adjacent apical oxygen located at the adjacent interstitial site, which shows ca. 0.5 eV lower free energy than that of the initial model. This result provides a new understanding for the location of the interstitial and the adjacent apical oxygens from an energetic point of view and supports previously published experimental data. It is found that alkaline earth doping at the A-site deteriorates the interstitial oxygen diffusion in La2-xA'xNiO4.25 materials, but concerning overall transport properties, Ca seems to be a good dopant from an energetic point of view, when compared with Ba and Sr.
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Polyvinylpyrrolidone is widely used in tablet formulations with the linear form acting as a wetting agent and disintegrant, whereas the cross-linked form is a superdisintegrant. We have previously reported that simply mixing the commercial cross-linked polymer with ibuprofen disrupted drug crystallinity with consequent improvements in drug dissolution behavior. In this study, we have designed and synthesized novel cross-linking agents containing a range of oligoether moieties that have then been polymerized with vinylpyrrolidone to generate a suite of novel excipients with enhanced hydrogen-bonding capabilities. The polymers have a porous surface and swell in the most common solvents and in water, properties that suggest their value as disintegrants. The polymers were evaluated in simple physical mixtures with ibuprofen as a model poorly water-soluble drug. The results show that the novel PVPs induce the drug to become "X-ray amorphous", which increased dissolution to a greater extent than that seen with commercial cross-linked PVP. The polymers stabilize the amorphous drug with no evidence for recrystallization seen after 20 weeks of storage.