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2.
J Xenobiot ; 14(1): 308-319, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38535494

RESUMO

Heme enzyme dysfunction causes a group of diseases called porphyrias. Particularly, a decrease in porphobilinogen deaminase, involved in the third step of heme biosynthesis, leads to acute intermittent porphyria (AIP). Considering our previous works demonstrating the multiplicity of brain metabolisms affected by porphyrinogenic agents, this study aimed to elucidate whether they cause any alteration on the mitochondrial respiratory chain. The activities of respiratory chain complexes (I to IV) were measured in encephalon mitochondria of CF1 male mice receiving volatile anesthetics: isoflurane (2 mL/kg) and sevoflurane (1.5 mL/kg), ethanol (30%), allylisopropylacetamide (AIA) (350 mg/kg), and barbital (167 mg/kg). Moreover, they were compared versus animals with pathological levels of 5-aminolevulinic acid (ALA, 40 mg/kg). Complex I-III activity was induced by isoflurane and decreased by AIA, ethanol, and ALA. Complex II-III activity was increased by sevoflurane and decreased by isoflurane and AIA. Complex II activity was increased by sevoflurane and barbital and decreased by AIA, ethanol, and ALA. Complex IV activity was increased by barbital and ALA and decreased by sevoflurane. The damage to the respiratory chain by ALA could be reflecting the pathophysiological condition of patients with AIP. Better understanding the broad effect of porphyrinogenic drugs and the mechanisms acting on the onset of AIP is vital in translational medicine.

3.
Healthcare (Basel) ; 11(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37830642

RESUMO

BACKGROUND: Fall prevention is an important indicator of the quality of patient care. Prevention includes the use of adequate footwear. Our objective is to determine the differences in the number of falls between patients with "adequate footwear" and "non slip socks", and their associated consequences, to support their use in the prevention of falls among hospitalized patients. METHODS: This is an observational prospective study on inpatient falls. Patient characteristics, fall circumstances, and injuries were collected through Clinical Report Forms, a review of fall reports, and medical records. Admitted patients over 18 years old were recruited from Geriatric and Internal Medicine Units over a brief period of 3 months. RESULTS: A total of 158 hospitalized patients were recruited. In total, 77 patients (48.73%) were assigned to the non-slip socks group, and 81 (51.27%) were assigned to the adequate footwear group. There were 21 falls during the study period, all of which were experienced by the adequate footwear group (p < 0.0001). The mean age of the patients who fell was 83.14 (range 60-100) years old. The most frequent reasons for admission among the patients who fell were COVID-19 infection (19%) and oncological complications (19%). Overall, 61.9% of patients had a high risk of falling. Most falls (76.1%) occurred in patient rooms, and most of these occurred while wandering around. The most frequent reason for falls was slipping (14/21). For 16 of 21 patients, falls did not have immediate consequences, while 5 had contusions and 1 suffered a wound. Nobody needed to be admitted to the ER or suffered external hemorrhages or loss of consciousness. CONCLUSIONS: Non-slip socks represent an adequate alternative to well-fitting rubber-soled footwear. It seems that non-slip socks could prevent falls among hospitalized patients; nevertheless, further studies are necessary to clarify their role in preventing hospital falls and reducing injury rates.

6.
Nutr. hosp ; 40(2): 428-435, mar.-abr. 2023. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-219342

RESUMO

Introducción: la hipovitaminosis D es frecuente en los receptores de trasplante renal (RTR) y se asocia con efectos deletéreos tanto a nivel óseo como extraóseo. El tratamiento con colecalciferol es eficaz para la normalización de la 25(OH)D, demostrándose un efecto benéfico sobre el eje calciotrópico; sin embargo, su efecto sobre el eje fosfotrópico no se ha reportado. El objetivo de este estudio fue evaluar el efecto de la normalización de las concentraciones séricas de 25(OH)D sobre el eje PTH/vitamina D/calcio-FGF23/klotho/fósforo en RTR tratados con colecalciferol, así como la asociación entre sus componentes. Métodos: estudio prospectivo en 23 RTR con hipovitaminosis D y antecedente de nefropatía primaria tratados con colecalciferol, en quienes se evaluó el eje PTH/vitamina D/calcio y FGF23/klotho/fósforo durante el estado de hipovitaminosis D y a la normalización de la 25(OH)D. Resultados: a la normalización de la 25(OH)D se evidenció una reducción de la PTH [103 (58,5-123,9) vs. 45,6 (30,1-65,1) pg/mL; p = 0,002] y un aumento del fósforo sérico [3,1 (2,3-3,5) vs. 3,3 (3-3,6) mg/dL; p = 0,01], sin diferencias en las concentraciones de calcio, klotho y FGF23. El tiempo para lograr la normalización de la 25(OH)D fue de 12 semanas (4-12), con una dosis de 5000 UI/día (4000-6000). Se corroboró una asociación positiva entre klotho y PTH (r = 0,54; p = 0,008; regresión lineal, β = 0,421; IC 95 %: 0,003-0,007; p = 0,045). (AU)


Background: hypovitaminosis D is frequent in kidney transplant recipient (KTR) patients and is associated with deleterious effects both at the bone and extraosseous levels. Treatment with cholecalciferol is effective for the normalization of 25(OH)D, demonstrating a beneficial effect on the calcium-tropic axis in other populations; however, its effect on the PTH/vitamin D/calcium and FGF23/klotho/phosphorus axis in RTR has not been reported. The aim of this study was to evaluate the effect of normalization of serum 25(OH)D concentrations on the PTH/vitamin D/calcium-FGF23/klotho/phosphorus axis in KTR treated with cholecalciferol, as well as the association between the components of this axis. Methods: a prospective study in 23 KTR with hypovitaminosis D, with evolution from 1 to 12 months post-transplantation, an estimated glomerular filtration rate > 60 mL/min/1.73 m2 and a history of primary nephropathy treated with cholecalciferol, in whom the PTH/vitamin D/calcium and FGF23/klotho/phosphorus axis was evaluated during the state of hypovitaminosis D and at normalization of 25(OH)D. Results: at the normalization of 25(OH)D, a reduction in PTH [103 (58.5-123.9) vs 45.6 (30.1-65.1) pg/mL; p = 0.002] and an increase in serum phosphorus [3.1 (2.3-3.5) vs 3.3 (3-3.6) mg/dL; p = 0.01] were evident, with no differences in calcium, klotho and FGF23 concentrations. The time to achieve normalization of 25(OH)D was 12 weeks (RIC, 4-12), with a dose of 5000 IU/day (RIC, 4000-6000). A positive association between klotho and PTH was corroborated (r = 0.54; p = 0.008; linear regression, β = 0.421; B = 0.004; 95 % CI, 0.003-0.007; p = 0.045). (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Deficiência de Vitamina D/tratamento farmacológico , Transplante de Rim , Estudos Prospectivos , Vitamina D , Colecalciferol/uso terapêutico , Hormônio Paratireóideo , Cálcio , Fósforo
7.
Nutr Hosp ; 40(2): 428-435, 2023 Apr 20.
Artigo em Espanhol | MEDLINE | ID: mdl-36926938

RESUMO

Introduction: Background: hypovitaminosis D is frequent in kidney transplant recipient (KTR) patients and is associated with deleterious effects both at the bone and extraosseous levels. Treatment with cholecalciferol is effective for the normalization of 25(OH)D, demonstrating a beneficial effect on the calcium-tropic axis in other populations; however, its effect on the PTH/vitamin D/calcium and FGF23/klotho/phosphorus axis in RTR has not been reported. The aim of this study was to evaluate the effect of normalization of serum 25(OH)D concentrations on the PTH/vitamin D/calcium-FGF23/klotho/phosphorus axis in KTR treated with cholecalciferol, as well as the association between the components of this axis. Methods: a prospective study in 23 KTR with hypovitaminosis D, with evolution from 1 to 12 months post-transplantation, an estimated glomerular filtration rate > 60 mL/min/1.73 m2 and a history of primary nephropathy treated with cholecalciferol, in whom the PTH/vitamin D/calcium and FGF23/klotho/phosphorus axis was evaluated during the state of hypovitaminosis D and at normalization of 25(OH)D. Results: at the normalization of 25(OH)D, a reduction in PTH [103 (58.5-123.9) vs 45.6 (30.1-65.1) pg/mL; p = 0.002] and an increase in serum phosphorus [3.1 (2.3-3.5) vs 3.3 (3-3.6) mg/dL; p = 0.01] were evident, with no differences in calcium, klotho and FGF23 concentrations. The time to achieve normalization of 25(OH)D was 12 weeks (RIC, 4-12), with a dose of 5000 IU/day (RIC, 4000-6000). A positive association between klotho and PTH was corroborated (r = 0.54; p = 0.008; linear regression, ß = 0.421; B = 0.004; 95 % CI, 0.003-0.007; p = 0.045). Conclusions: treatment with cholecalciferol is effective for the normalization of 25(OH)D, with a beneficial effect on calcium-phosphotropic metabolism characterized by a reduction in PTH concentration, without significant changes in calcemia or calciuria, as well as an increase in phosphatemia, without modifications in FGF23 or klotho concentrations.


Introducción: Introducción: la hipovitaminosis D es frecuente en los receptores de trasplante renal (RTR) y se asocia con efectos deletéreos tanto a nivel óseo como extraóseo. El tratamiento con colecalciferol es eficaz para la normalización de la 25(OH)D, demostrándose un efecto benéfico sobre el eje calciotrópico; sin embargo, su efecto sobre el eje fosfotrópico no se ha reportado. El objetivo de este estudio fue evaluar el efecto de la normalización de las concentraciones séricas de 25(OH)D sobre el eje PTH/vitamina D/calcio-FGF23/klotho/fósforo en RTR tratados con colecalciferol, así como la asociación entre sus componentes. Métodos: estudio prospectivo en 23 RTR con hipovitaminosis D y antecedente de nefropatía primaria tratados con colecalciferol, en quienes se evaluó el eje PTH/vitamina D/calcio y FGF23/klotho/fósforo durante el estado de hipovitaminosis D y a la normalización de la 25(OH)D. Resultados: a la normalización de la 25(OH)D se evidenció una reducción de la PTH [103 (58,5-123,9) vs. 45,6 (30,1-65,1) pg/mL; p = 0,002] y un aumento del fósforo sérico [3,1 (2,3-3,5) vs. 3,3 (3-3,6) mg/dL; p = 0,01], sin diferencias en las concentraciones de calcio, klotho y FGF23. El tiempo para lograr la normalización de la 25(OH)D fue de 12 semanas (4-12), con una dosis de 5000 UI/día (4000-6000). Se corroboró una asociación positiva entre klotho y PTH (r = 0,54; p = 0,008; regresión lineal, ß = 0,421; IC 95 %: 0,003-0,007; p = 0,045). Conclusiones: el tratamiento con colecalciferol es eficaz para la normalización de la 25(OH)D con un efecto benéfico sobre el metabolismo calcio-fosfotrópico caracterizado por una reducción de la PTH y un incremento de la fosfatemia, sin modificaciones de calcemia, calciuria, FGF23 o klotho.


Assuntos
Transplante de Rim , Deficiência de Vitamina D , Humanos , Vitamina D , Cálcio , Estudos Prospectivos , Hormônio Paratireóideo , Vitaminas , Colecalciferol/uso terapêutico , Fósforo , Deficiência de Vitamina D/tratamento farmacológico
8.
Artigo em Inglês | MEDLINE | ID: mdl-36901475

RESUMO

(1) Objective: The aim of this study is to synthesize the effects of physical therapy on pain, frequency, or duration management in the short, medium, and long term in adult patients diagnosed with Tension-type headache (TTH). (2) Background: Tension-type headache (TTH) is the most common headache with migraine and its pathophysiology and treatment has been discussed for years without reaching a consensus. (3) Methods: A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The review was registered in PROSPERO (CRD42020175020). The systematic search for clinical trials was performed in the databases PubMed, CINAHL, Cochrane Central Register of Controlled Trials, PEDro, Scopus, SciELO and Dialnet. Articles were selected according to the inclusion and exclusion criteria, regarding the effectiveness of physical therapy interventions on adult patients with TTH published in the last 11 years with a score ≥ 6 in the PEDro Scale (Physiotherapy Evidence Database). (4) Results: In total, 120 articles were identified, of which 15 randomized controlled trials were finally included in order to determine the inclusion criteria. Changes in pain intensity, headache frequency or headache duration of individual studies were described (5) Conclusions: This systematic review shows that there is no standardized physical therapy protocol for the approach to tension headache, although all the techniques studied to date address in one way or another the cranio-cervical-mandibular region. The approach to the cranio-cervical-mandibular region reports significant effects in terms of decreasing the intensity of pain and frequency of headache episodes in the short and medium term. More long-term longitudinal studies are needed.


Assuntos
Cefaleia do Tipo Tensional , Adulto , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Cefaleia , Modalidades de Fisioterapia , Dor
9.
Artigo em Inglês | MEDLINE | ID: mdl-36674339

RESUMO

This research analyzes the influence of COVID-19 and public health spending policies on the economic sustainability of Spanish private hospitals. Moreover, it explores the relationship between public health spending policies and the spread of COVID-19 in Spain. Private health care is an understudied sector, yet it is fundamental to the health of citizens. Moreover, the economic causes linked to the spread of the pandemic have not yet been clearly established. Therefore, this work covers a gap in the literature. Private hospital profitability was analyzed by applying ordinary least squares and panel data regressions on financial and macroeconomic data for the period 2017-2020. The spread of COVID-19 was examined by means of cluster and component analysis. The results show that the COVID-19 pandemic negatively affected the economic sustainability of Spanish private hospitals, which was also influenced by public health spending. In turn, the spread of the pandemic was mainly related to population density, but was also influenced by public health spending and the gross domestic product of the region. Therefore, policymakers must consider that it is essential to make adequate investments in the healthcare system to cope with pandemics such as COVID-19. In addition, managers can see how corporate social responsibility is a valuable strategy for maintaining hospital profitability.


Assuntos
COVID-19 , Gastos em Saúde , Humanos , Saúde Pública , Pandemias , COVID-19/epidemiologia , Atenção à Saúde
10.
Nutrients ; 14(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36558394

RESUMO

Irritable Bowel Syndrome (IBS) is usually a lifelong state that disturbs the digestive system. IBS has been linked to low-grade inflammation and the release of inflammatory mediators into the bloodstream. This could be associated with the degree of obesity presented by patients with IBS. Reports imply that IBS is more frequent in obese patients than in the overall population, with a prevalence of up to 31%. Here, we evaluated the serum levels of immunological and inflammation molecules and their correlation with Body Mass Index in IBS patients and the healthy control (HC). Seventy-nine serum samples of the IBS patients and thirty-five of the HC group were analyzed to determine the levels of each molecule and compare them with their BMI. Serum levels of C3 and C4 were significantly increased in IBS patients. C3 and C4 levels were higher in IBS-M and IBS-D subtypes compared with the HC group. When patients were grouped by BMI, a positive correlation between serum C3 (r = 0.49, p < 0.0001) and CRP (r = 0.40, p < 0.001) levels was found. Our results show, for the first time, a correlation between immunological molecules and BMI in IBS patients, suggesting that the inflammatory nature of obesity could contribute to the development of the symptoms in IBS through the stimulation and release of proteins as complement components and CRP.


Assuntos
Síndrome do Intestino Irritável , Obesidade , Humanos , Proteína C-Reativa/metabolismo , Complemento C3 , Inflamação , Obesidade/complicações
12.
PLoS One ; 17(12): e0276885, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36477461

RESUMO

The natural stone sector is an important driver of the Spanish and Italian economies, which underwent internationalization after the financial crisis of 2008 as part of a survival and development strategy. This article aims to study the financial and economic profitability of this sector in the two leading European production countries, as well as its determinants. For this purpose, the economic-financial data of a sample composed of 453 companies (203 Spanish and 250 Italian) from 2015-2019 were analyzed using the multiple linear regression methodology. To address the problems of possible endogeneity and omission of variables in the model, the dependent variable was used as a regressor with one and two lags, and panel data with fixed effects were considered after performing the Hausman test. The results show significant differences between the two countries, with higher profitability in Italy. Company size, company growth (measured as the change in assets), and the variation in the country's GDP all positively affected profitability. At the same time, the level of indebtedness showed a negative relationship. The country's inflation rate and gender diversity in top management were shown to be non-relevant variables. The research conducted indicates that, to increase profitability, Spanish and Italian companies in the natural stone sector should undergo mergers in order to grow in size, increase efficiency in the use of assets, reduce their dependence on external financing, and promote equity capital. In addition, Italian companies should reduce the average period of payment to suppliers to lower deferral costs, and boost exports to become less dependent on the country's domestic economy.


Assuntos
Indústrias , Europa (Continente) , Itália , Espanha , Indústrias/economia
13.
Front Psychol ; 13: 1049175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438339

RESUMO

Gender equality is included in the United Nations Sustainable Development Goals and in the Global Jobs Pact of the International Labour Organization. Many countries, especially in Europe, are incorporating legal quotas into their legislation to oblige companies to increase the presence of women in the highest positions of responsibility. This measure has been controversial and widely debated, and so it is of great interest to analyze the economic effects that the incorporation of women brings. The aim of this paper is to analyze the relationship between the percentage of women on the board of directors and systematic market risk, measured using the beta of stocks in the S&P 500 and Euro Stoxx 300 indexes from 2015 to 2019. Applying OLS regressions with instrumental variables, fixed effects panel data, and a GMM estimation, the results show a negative and significant relationship for the U.S. market. However, this relationship was not confirmed for the European market.

14.
Healthcare (Basel) ; 10(11)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36360592

RESUMO

The health systems of developed countries aim to reduce the mortality rates of their populations. To this end, they must fight against the unhealthy habits of citizens, such as smoking, excessive alcohol consumption, and sedentarism, since these result in a large number of deaths each year. Our research aims to analyze whether an increase in health resources influences the number of deaths caused by the unhealthy habits of the population. To achieve this objective, a sample containing key indicators of the Spanish health system was analyzed using the partial least squares structural equation modeling (PLS-SEM) method. The results show how increasing public health spending and, thus, the resources allocated to healthcare can curb the adverse effects of the population's unhealthy habits. These results have important implications for theory and practice, demonstrating the need for adequate investment in the healthcare system to reduce mortality among the population.

15.
Healthcare (Basel) ; 10(10)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36292558

RESUMO

(1) Background: The aim of this systematic review focused on analyzing the impact of depression on the functional outcome of the elderly stroke victim and how this disorder affects both the female and the male population. (2) Methods: We conducted a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The review was registered in PROSPERO (ID 346284). The systematic search for clinical trials was performed in the databases Pubmed, Otseeker, Scopus, Web of Science, Psycinfo, Medline Complete, ScienceDirect, SciELO, and Dialnet. Articles were selected according to the inclusion and exclusion criteria, including those dealing with post-stroke depression in adults whose psychological status had changed. Studies that only assessed the psychological state of caregivers were excluded. (3) Results: In total, 609 articles were identified, of which 11 randomized controlled trials were finally included in the review. The results indicate that post-stroke depression influences the recovery of functionality and quality of life. In addition, the need to detect the mood of the adult population after the stroke and to provide individualized treatment according to the characteristics of the person is highlighted. (4) Conclusions: This systematic review shows how early detection of post-stroke depressive symptoms can improve the degree of disability and quality of life of the person, especially in women.

16.
Front Public Health ; 10: 953827, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211653

RESUMO

Well-being inequalities arising from different healthcare expenditure public policies is currently a hot topic at a national scale, but especially so at a sub-national level because the inequalities in question are among citizens of the same country. Spain is an optimal study area to carry out research on this topic because it is considered to have one of the best health systems in the world, it is one of the top-ranking countries in terms of life expectancy rates (the indicators we use for well-being), and it has a decentralized public health system with significantly different regional healthcare expenditure public policies. Given that the factors involved in the complex direct, indirect, and second-order relationships between well-being and health spending are latent in nature, and that there are more hypotheses than certainties regarding these relationships, we propose a partial least squares structural equation modeling specification to test the research hypotheses and to estimate the corresponding impacts. These constructs are proxied by a set of 26 indicators, for which annual values at a regional scale were used for the period 2005-2018. From the estimation of this model, it can be concluded that mortality, expenditure and resources are the factors that have the greatest impact on well-being. In addition, a cluster analysis of the indicators for the constructs included in this research reveals the existence of three clearly differentiated groups of autonomous communities: the northern part of the country plus Extremadura (characterized by the lowest well-being and the highest mortality rates), Madrid (with the best results in well-being and mortality, the lowest public health expenditure per inhabitant and percentage of pharmaceutical spending, and the highest percentage in specialty care services and medical staff spending), and the rest of the country (south-eastern regions, with similar well-being values to those of the first group but with less health expenditure). Finally, a principal component analysis reveals that "healthiness" and "basic spending" are the optimal factors for mapping well-being and health spending in Spain.


Assuntos
Atenção à Saúde , Gastos em Saúde , Humanos , Preparações Farmacêuticas , Política Pública , Espanha
17.
Healthcare (Basel) ; 10(9)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36141257

RESUMO

Stroke is one of the main causes of disability in adulthood. Its rehabilitation is a complex process that requires a multidisciplinary team of specialised professionals. The main goal of this review was to determine the impact of occupational therapy intervention post-stroke on the home discharge process. A systematic search was carried out of the following databases: Pubmed, Web of Science, PsycINFO, Scopus, Otseeker, and Dialnet. A screening was performed taking into account the type of article, including exclusively RCT, and type of intervention, only including interventions within the scope of occupational therapy that take place during the process of hospital discharge post-stroke. A total of 2285 citations were identified in the search from which 13 articles met the inclusion criteria. Comparisons of the groups indicated that early occupational therapy intervention during the process of hospital discharge can be effective in terms of functional recovery and can lead to the caregiver seeing improvements in self-efficacy and fatigue. In addition, the inclusion of a caregiver in the intervention influences the patient's adherence to treatment, leading to a reduction in the cost of treatment and rehabilitation.

18.
Healthcare (Basel) ; 10(7)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35885756

RESUMO

In recent years, public authorities have invested large amounts of public money in trying to reduce waiting times for consultations and operations with the aim of improving the quality of the healthcare system. Our research aims to analyze the effect of these investments on patient satisfaction through the mediating relationship of waiting times for consultations and operations, as well as from a gender perspective. By studying a series of key indicators of the Spanish healthcare system and applying partial least squares structural equation modelling (PLS-SEM), the findings show that the model explains 12.10% of the variance in consultant waiting times, 51.90% in operation waiting times, and 27.00% in patient satisfaction. We found that increased public spending leads to increased patient satisfaction by reducing waiting times. However, no gender-based differences were found. The results provide exciting implications for theory and practice, indicating how policymakers can orient their strategies towards improving patient satisfaction.

19.
Emerg Infect Dis ; 28(9): 1847-1851, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35820165

RESUMO

During June 2022, Spain was one of the countries most affected worldwide by a multicountry monkeypox outbreak with chains of transmission without identified links to disease-endemic countries. We provide epidemiologic features of cases reported in Spain and the coordinated measures taken to respond to this outbreak.


Assuntos
Surtos de Doenças , Humanos , Vírus da Varíola dos Macacos , Espanha/epidemiologia
20.
Molecules ; 27(5)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35268734

RESUMO

This paper provides the basis for understanding the preparation and properties of an old, but advanced material: activated carbon. The activated carbons discussed herein are obtained from "green" precursors: biomass residues. Accordingly, the present study starts analyzing the components of biomass residues, such as cellulose, hemicellulose, and lignin, and the features that make them suitable raw materials for preparing activated carbons. The physicochemical transformations of these components during their heat treatment that lead to the development of a carbonized material, a biochar, are also considered. The influence of the chemical activation experimental conditions on the yield and porosity development of the final activated carbons are revised as well, and compared with those for physical activation, highlighting the physicochemical interactions between the activating agents and the lignocellulosic components. This review incorporates a comprehensive discussion about the surface chemistry that can be developed as a result of chemical activation and compiles some results related to the mechanical properties and conformation of activated carbons, scarcely analyzed in most published papers. Finally, economic, and environmental issues involved in the large-scale preparation of activated carbons by chemical activation of lignocellulosic precursors are commented on as well.


Assuntos
Biomassa
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