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1.
J Colloid Interface Sci ; 672: 370-382, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850864

RESUMO

Improving ligand-to-active metal charge transfer (LAMCT) by finely tuning the organic ligand is a decisive strategy to enhance charge transfer in metal organic frameworks (MOFs)-based catalysts. However, in most MOFs loaded with active metal catalysts, electron transmission encounters massive obstacle at the interface between the two constituents owing to poor LAMCT. Herein, amines (-NH2) functionalized MOFs (NH2-MIL-101(Cr)) encapsulated active metal Pt nanoclusters (NCs) catalysts are synthesized by the polyol reduction method and utilized for the photoreduction of CO2. Surprisingly, the introduction of -NH2 (electron donating) groups within the matrix of MIL-101(Cr) improved the electron migration through the LAMCT process, fostering a synergistic interaction with Pt. The combined experimental analysis exposed the high number of metallic Pt (Pt0) in Pt@NH2-MIL-101(Cr) catalyst through seamless electron shuttling from N of -NH2 group to excited Pt generating versatile hybrid Pt-N catalytic centres. Consequently, these versatile hybrid catalytic centres act as electro-nucleophilic centres, which enable the efficient and selective conversion of CO bond in CO2 to harvest CH4 (131.0 µmol.g-1) and maintain excellent stability and selectivity for consecutive five rounds, superior to Pt@MIL-101(Cr) and most reported catalysts. Our study verified that the precise tuning of organic ligands in MOFs immensely improves the surface-active centres, electron migration, and catalytic selectivity of the excited Pt NCs catalysts encaged inside MOFs through an improved LAMCT pathway.

2.
Cureus ; 16(5): e59753, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38840991

RESUMO

BACKGROUND: Tinea pedis, commonly known as athlete's foot, is a fungal infection affecting the skin of the feet, primarily between the toes. Despite being a common condition, there may be gaps in knowledge and practices regarding its transmission, risk factors, and treatment options among the general population. METHODS: This study adopted a cross-sectional research design. The study involved 2371 adult population in Saudi Arabia. The questionnaire was distributed online through social media means. Data was analyzed using IBM SPSS Statistics for Windows, Version 27 (Released 2020; IBM Corp., Armonk, New York, United States). RESULTS: A significant portion (66.1%) of respondents reported not examining their feet regularly. The majority (80.7%) of the respondents reported regular use of nail scissors as the common practice. The results further revealed that the majority of respondents (71.7%) were not aware of tinea pedis. Similarly, a large proportion (77.3%) of respondents were unaware of the risk factors associated with tinea pedis. However, among those aware, the most recognized risk factor was diabetes mellitus (82.3%), followed by peripheral arterial disease (37.1%), and immunocompromised conditions like HIV (31.3%). There was a significant association (p = 0.001) between regular foot examination practices and awareness of tinea pedis. CONCLUSION: In conclusion, there is low awareness regarding tinea pedis among the Saudi Arabian population. Only a small proportion demonstrated good knowledge of the condition and its symptoms. However, there is a relatively higher awareness of specific risk factors such as diabetes mellitus and peripheral arterial disease. Hence, it is imperative to enhance education and awareness campaigns to address the gaps in understanding tinea pedis, its associated risk factors, and symptoms, particularly among individuals engaged in physical activities and those who regularly wear sports shoes.

3.
RSC Adv ; 14(25): 17535-17546, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38828272

RESUMO

The biological synthesis of zinc oxide nanoparticles (ZnO NPs) from plant extracts has emerged as a novel method for producing NPs with great scalability and biocompatibility. The present study is focused on bio-fabricated zinc oxide nanomaterial characterization and investigation of its photocatalytic and antifungal activities. ZnO NPs were biosynthesized using the leaf extract of Polyalthia longifolia without using harmful reducing or capping chemicals, which demonstrated fungicidal activity against Fusarium oxysporum f. sp. ciceris. The results showed that the inhibition of the radial growth of F. oxysporum f. sp. ciceris was enhanced as the concentration increased from 100 ppm to 300 ppm. The effectiveness of the photocatalytic activity of biosynthesized ZnO NPs was analyzed using MB dye degradation in aqueous medium under ultraviolet (UV) radiation and natural sunlight. After four consecutive cycles, the photocatalytic degradation of MB was stable and was 84%, 83%, 83%, and 83%, respectively, during natural sunlight exposure. Under the UV sources, degradation reached 92%, 89%, 88%, and 87%, respectively, in 90 minutes. This study suggests that the ZnO NPs obtained from plant extract have outstanding photocatalytic and antifungal activities against F. oxysporum f. sp. ciceris and have the potential for application as a natural pest control agent to reduce pathogenesis.

4.
J Family Med Prim Care ; 13(3): 997-1003, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38736786

RESUMO

Background: Assessment of awareness and knowledge of the general population regarding Monkeypox is rarely investigated on a global level. The World Health Organization (WHO) reported a lack of knowledge about monkeypox as one of the main challenges facing authorities in implementing effective preventive strategies. This study aims to assess the awareness and knowledge of the general adult population about Monkeypox disease. Subjects and Methods: An online population-based cross-sectional study was carried out in Jeddah, Saudi Arabia, among a snowball sample of adult persons (>18 years old). A self-administered online Arabic and English questionnaires was utilized in this study. It consists of three main parts: sociodemographic characteristics of the patients, perception towards Monkeypox disease and assessment of the knowledge about Monkeypox disease through 23 multiple-choice questions with "Yes", "No" and "don't know" responses. Results: A total of 387 adults were included in the study. Females represented 72.6% of them. Almost two-thirds (63.8%) aged between 26 and 45 years. More than half (55.6%) of the participants believed that monkeypox will affect social and economic life like the COVID-19 pandemic while 30.7% considered Monkeypox as a conspiracy or bioterrorism. Overall, almost half (50.4%) of the participants expressed excellent level of knowledge, whereas only 4.4% had poor level of knowledge. The highest level of excellent knowledge about Monkeypox disease was observed among participants in the age group 26-45 years (55.1%), whereas the lowest was observed among those in the age group 46-60 years (39.7%), P = 0.001. More educated participants (university/postgraduates) were more knowledgeable about Monkeypox disease as 53.5% of them had excellent level of knowledge compared to 33.3% of those below secondary school educational level, P = 0.047. Conclusion: The knowledge of the general population about Monkeypox is acceptable. However, defective knowledge was observed regarding the fact that Monkeypox is not a new infection that appeared in the year 2022 as well as about the availability of a monkeypox vaccine in Saudi Arabia. Therefore, it is recommended to organize educational activities about the disease for general population targeted mainly lower educated and elderly subjects.

5.
Heliyon ; 10(9): e30762, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38765132

RESUMO

In survival and stochastic lifespan modeling, numerous families of distributions are sometimes considered unnatural, unjustifiable theoretically, and occasionally superfluous. Here, a novel parsimonious survival model is developed using the Bilal distribution (BD) and the Kavya-Manoharan (KM) parsimonious transformation family. In addition to other analytical properties, the forms of probability density function (PDF) and behavior of the distributions' hazard rates are analyzed. The insights are theoretical as well as practical. Theoretically, we offer explicit equations for the single and product moments of order statistics from Kavya-Manoharan Bilal Distribution. Practically, maximum likelihood (ML) technique, which is based on simple random sampling (SRS) and ranked set sampling (RSS) sample schemes, is employed to estimate the parameters. Numerical simulations are used as the primary methodology to compare the various sampling techniques.

6.
Int J Biol Macromol ; 268(Pt 1): 131558, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614166

RESUMO

Water contamination caused by toxic compounds has emerged as one of the most severe challenges worldwide. Biomass-based nanocomposites offer a sustainable and renewable alternative to conventional materials. In this study, a nanocomposite of mint and cellulose acetate (Mint-CA) was prepared and employed as a supportive material for Cu nanoparticles (CuNPs) and Ag nanoparticles (AgNPs). The selectivity of CuNPs@mint-CA and AgNPs@mint-CA was assessed by comparing their performance in the reduction reaction of various dyes solutions. AgNPs@mint-CA exhibited superior catalytic performance, with a removal of 95.2 % for methyl orange (MO) compared to 68 % with CuNPs@mint-CA. The absorption spectra of MO exhibited a distinct peak at 464 nm. The reduction reaction of MO by AgNPs@mint-CA followed pseudo-first-order-kinetic with a rate constant of k = 0.0063 min-1 (R2 = 0.928). The highest removal of MO was achieved under the following conditions: a catalyst weight of 40 mg, an initial MO concentration of 0.07 mM, the addition of 0.5 mL of 0.1 M NaBH4, and a temperature of 25 °C. Furthermore, the AgNPs@mint-CA catalyst exhibited exceptional reducibility even after five use cycles, highlighting its potential for efficiently removing MO.


Assuntos
Compostos Azo , Celulose , Nanopartículas Metálicas , Compostos Azo/química , Celulose/química , Celulose/análogos & derivados , Nanopartículas Metálicas/química , Catálise , Prata/química , Nanocompostos/química , Mentha/química , Oxirredução , Poluentes Químicos da Água/química , Cinética , Cobre/química
7.
Heliyon ; 10(5): e26794, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38562494

RESUMO

Nadarajah and Haghighi distribution (NHD) inferences problem has been discussed under unified hybrid censoring scheme (UHCS) in the existence of competing risks model. Competing risks model is defined by time-to-failure under more than one cause of failure, which can be dependent or independent. This study focuses on discussing the case of failure partially observed causes of failure competing risks model. We obtain various inferences: we first obtain the MLE, in addition, we construct approximate confidence intervals (ACIs). Second, we obtain the Bayes estimator via SELF and related highest posterior density (HPD) using Markov Chain Monte Carlo (MCMC). Finally, an electrical appliances data set and simulation studies have been analyzed for further illustrations.

8.
J Basic Microbiol ; 64(5): e2300744, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38466146

RESUMO

Tenebrio molitor L., also known as the mealworm, is a polyphagous insect pest that infests various stored grains worldwide. Both the adult and larval stages can cause significant damage to stored grains. The present study focused on isolating entomopathogenic fungi from an infected larval cadaver under environmental conditions. Fungal pathogenicity was tested on T. molitor larvae and pupae for 12 days. Entomopathogenic fungi were identified using biotechnological methods based on their morphology and the sequence of their nuclear ribosomal internal transcribed spacer (ITS). The results of the insecticidal activity indicate that the virulence of fungi varies between the larval and pupal stages. In comparison to the larval stage, the pupal stage is highly susceptible to Metarhizium rileyi, exhibiting 100% mortality rates after 12 days (lethal concentration 50 [LC50] = 7.8 × 106 and lethal concentration 90 (LC90) = 2.1 × 1013 conidia/mL), whereas larvae showed 92% mortality rates at 12 days posttreatment (LC50 = 1.0 × 106 and LC90 = 3.0 × 109 conidia/mL). The enzymatic analyses revealed a significant increase in the levels of the insect enzymes superoxide dismutase (4.76-10.5 mg-1) and glutathione S-transferase (0.46-6.53 mg-1) 3 days after exposure to M. rileyi conidia (1.5 × 105 conidia/mL) compared to the control group. The findings clearly show that M. rileyi is an environmentally friendly and effective microbial agent for controlling the larvae and pupae of T. molitor.


Assuntos
Larva , Metarhizium , Controle Biológico de Vetores , Pupa , Tenebrio , Animais , Tenebrio/microbiologia , Metarhizium/patogenicidade , Metarhizium/crescimento & desenvolvimento , Larva/microbiologia , Pupa/microbiologia , Virulência , Superóxido Dismutase/metabolismo , Glutationa Transferase/metabolismo
9.
J Comput Chem ; 45(18): 1576-1586, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38516839

RESUMO

Lead-free double perovskites are unique materials for transport and optoelectronic applications that use clean resources to generate energy. Using first-principle computations, this study thoroughly investigates the structural, thermoelectric, and optical attributes of A2TlAgF6 (A = Rb, Cs). Tolerance factor and formation energy estimates are used to verify that these materials exist in the cubic phase. Elastic constants with high melting temperature values are ductile when evaluated for mechanical stability using the Born stability criterion. The optical absorption band is adjusted from 2 to 4 eV via band gaps of 1.88 and 1.99 eV, as indicated by band structures. Analysis of optical properties reveals perfect absorption in the visible spectrum, whole polarization, and low optical loss. Furthermore, thermoelectric properties are assessed at 300, 500, and 700 K in the range of -0.5 to 3 eV for chemical potential (µ). The materials exhibit significant improvements in the Figure of Merit scale due to their elevated electrical conductivity, Seebeck coefficient, and extremely low thermal conductivity values.

10.
Micromachines (Basel) ; 15(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38398995

RESUMO

This paper presents the investigations toward the direct use of bentonite clay (Al2H2O6Si) nanoparticles to act like a saturable absorber (SA) for the Q-switched pulse operation of an erbium-doped fiber laser (EDFL). The measured results reveal that with the incorporation of bentonite clay nanopowder as a SA, an EDFL is realized with a Q-switching mechanism starting at a pump power of 30.8 mW, and a Q-switched emission wavelength was noticed at 1562.94 nm at 142 mW pump power. With an increased pump from 30.8 mW to 278.96 mW, the temporal pulse parameters including minimum pulse duration and maximum pulse repetition rates were reported as 2.6 µs and 103.6 kHz, respectively. The highest peak power, signal-to-noise ratio, output power and pulse energy were noticed to be 16.56 mW, 51 dB, 4.6 mW, and 47 nJ, respectively, at a highest pump power of 278.96 mW. This study highlights the significance of bentonite clay (Al2H2O6Si) nanoparticles as a potential candidate for a saturable absorber for achieving nonlinear photonics applications.

11.
Cureus ; 16(1): e51464, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298302

RESUMO

Background and aim Assessing the knowledge of healthcare professionals regarding the Airway, Breathing, Circulation, Disability, and Exposure (ABCDE) approach is crucial since it prioritizes the initial assessment and treatment of patients who are critically ill, regardless of the underlying cause or their age. Since adherence requires knowledge, this study aimed to evaluate the knowledge level of the ABCDE approach among healthcare professionals. Methods This cross-sectional study among healthcare professionals was performed from April to August 2023 in Taif City, Saudi Arabia. The study included healthcare professionals employed in departments exposed to patients with critical illnesses and excluded those from other specialties and individuals from outside Taif City. Data was collected via Google Forms using a previously validated questionnaire designed to assess the ABCDE approach knowledge among healthcare professionals. Statistical analysis was conducted using IBM SPSS, version 26. Results The study included 242 healthcare professionals with a mean (SD) age of 35.77 (9.93) years. About half of the participants were female (52.5%) nurses (50.8%) and had been working in intensive care units (ICU) and neonate intensive care units (NICU) (41.4%). The mean (SD) of the participants' working experience was 9.28 (8.295) years. The overall mean test score was 52.94 % (SD 16.27). The mean knowledge score among males was significantly higher than females (56.37% vs. 49.85%, respectively) (p-value= 0.001). The mean knowledge score was significantly higher among medical specialists and residents (63.308% and 55.67%) than among nurses (46.34%) (p-value <0.001). Attending an advanced trauma life support course and theoretical lecture significantly impacted the total knowledge score among the participants (p-values= 0.001 and <0.001, respectively). The total knowledge significantly increased with age (r: 0.265, p-value <0.001). Years of experience correlated with total knowledge score; with increasing years of experience, the total knowledge was significantly increased (r: 0.248, p-value <0.001). Conclusion The ABCDE approach is a valuable tool for the initial examination and treatment of patients in acute medical and surgical emergencies. The findings indicate that there is a need for further awareness programs and training on the ABCDE approach, as the total knowledge score among healthcare professionals was found to be suboptimal. Further research is needed to assess the association between knowledge level and clinical performance in different healthcare settings within Saudi Arabia.

12.
Nanoscale Adv ; 6(2): 680-689, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38235097

RESUMO

Thermoelectric materials have received great interest because they directly tap into the vast reserves of currently underused thermal energy, in an environmentally friendly manner. In this work, we investigated the electronic, optical and thermoelectric properties of novel ZnMN2 (M = Ge, Sn, Si and N = S, Se, Te) monolayers by performing density functional theory calculations. The dynamic and thermal stabilities of ZnMN2 (M = Ge, Sn, Si and N = S, Se, Te) monolayers were confirmed by their phonon band structures and ab initio molecular dynamics (AIMD) simulations, which showed that all the studied monolayers are stable. Calculated electronic band structures showed that ZnSiTe2, ZnGeSe2, and ZnSnTe2 have a direct band gap, while the remaining monolayers have an indirect band gap. Optical properties in terms of the imaginary part of the dielectric function have also been investigated, which showed that all the first excitonic peaks lie in the visible region. Transport coefficients, such as the Seebeck coefficient (S), electrical conductivity (σ) and power factor (PF) were calculated using the Boltzmann theory and plotted against chemical potential. The results demonstrated that the peak values of the p-type region for the PF are greater than those of the n-type region. Notably, ZnSiTe2 exhibits a large PF due to its smaller Seebeck coefficient and higher electrical conductivity compared to ZnSnS2, indicating that it is a promising candidate for thermoelectric applications. Our findings reveal that ZnMN2 (M = Ge, Sn, Si and N = S, Se, Te) monolayers open up new possibilities for optoelectronics and thermoelectric device applications.

13.
J Biochem Mol Toxicol ; 38(1): e23578, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37927152

RESUMO

Lung cancer is one of the most common cancers in men. Although many diagnostic and treatment regimens have been followed in the treatment for lung cancer, increasing mortality rate due to lung cancer is depressing and hence requires alternative plant based therapeutics with with less side-effects. Myrtenol exhibits anti-inflammatory and antioxidant properties. Hence we intended to study the effect of Myrtenol on B(a)P-induced lung cancer. Our study showed that B(a)P lowered hematological count, decreased phagocyte and avidity indices, nitroblue tetrazolium (NBT) reduction, levels of immunoglubulins, antioxidant levels, whereas Myrtenol treatment restored them back to normal levels. On the other hand, xenobiotic and liver dysfunction marker enzymes and pro-inflammatory cytokines were elevated on B(a)P exposure, which retuned back to normal by Myrtenol. This study thus describes the immunomodulatory and antioxidant effects of Myrtenol on B[a]P-induced immune destruction.


Assuntos
Monoterpenos Bicíclicos , Neoplasias Pulmonares , Humanos , Masculino , Camundongos , Animais , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/tratamento farmacológico , Citocinas/metabolismo , Benzo(a)pireno/toxicidade , Antioxidantes/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Biomarcadores Tumorais/metabolismo , Pulmão/metabolismo
14.
Cureus ; 15(11): e49460, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38152827

RESUMO

INTRODUCTION: Irritable bowel syndrome (IBS) presents a significant challenge in the medical field due to its complex nature as a functional gastrointestinal illness (FGID) without clear biological markers. Diagnosis often involves ruling out other potential causes, leading to frustration for patients and difficulty in effective treatment. Given its high prevalence among FGIDs, primary healthcare (PHC) physicians play a crucial role in its initial assessment and management. METHODS: This cross-sectional study surveyed 623 PHC physicians using a structured, closed-ended questionnaire. Employing a multistage sampling approach, physicians were selected from various provinces and cities in Saudi Arabia. Clusters within these cities were also sampled. RESULTS: The research revealed that a majority of physicians (n = 411, 66%) exhibited a strong awareness of the Rome IV criteria, essential for diagnosing IBS. This awareness correlated significantly with variables, such as age, nationality, marital status, specialty, classifications, and years of experience. CONCLUSION: PHC physicians in the study demonstrated a commendable level of familiarity with the Rome IV criteria for diagnosing IBS. Their knowledge was particularly robust concerning symptoms outlined in these criteria. However, there is room for improvement in their understanding, attitude, and application of the Rome IV guidelines in practice. Addressing these gaps could enhance the overall management of IBS cases by these physicians.

15.
Nanoscale Adv ; 5(21): 5829-5837, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37881719

RESUMO

Binding energies, AIMD simulation and phonon spectra confirm both the thermal and dynamical stabilities of model-I and model-II of MSSe-PtO2 (M = Mo, W) vdWHs. An indirect type-II band alignment in both the models of MSSe-PtO2 vdWHs and a larger Rashba spin splitting in model-II than in model-I provide a platform for experimental design of MSSe-PtO2 vdWHs for optoelectronics and spintronic device applications. Transfer of electrons from the MSSe layer to the PtO2 layer at the interface of MSSe-PtO2 vdWHs makes MSSe (PtO2) p(n)-type. Large absorption in the visible region of MoSSe-PtO2 vdWHs, while blue shifts in WSSe-PtO2 vdWHs are observed. In the case of model-II of MSSe-PtO2 vdWHs, a further blue shift is observed. Furthermore, the photocatalytic response shows that MSSe-PtO2 vdWHs cross the standard water redox potentials confirming their capability to split water into H+/H2 and O2/H2O.

16.
J Comput Chem ; 44(32): 2442-2452, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37605480

RESUMO

The double perovskites are become the emerging aspirant to fulfill the demand of energy. Therefore, the optoelectronic, elastic and transport characteristics of Ba2 XMoO6 (X = Zn, Cd) are addressed systemically. The elastic constants show the mechanical stability. The nature of Ba2 ZnMoO6 is brittle and Ba2 CdMoO6 is ductile with large values of Debye temperature covalent bonding. The electronic band structures exhibit band gaps of 2.81 and 2.98 eV, which increase their importance for optoelectronic applications. The absorption of light energy, optical loss, refractive index, polarization of light energy are addressed in the energy range zero to 14 eV. Furthermore, thermoelectric characteristics are computed against chemical potentials at 300, 600, and 900 K. The chemical potential decides the p-type nature, with holes as majority carriers. The increasing temperature increases the power factor and figure of merit. Therefore, the optoelectronic and thermoelectric characteristics reveals the importance of studied DPs for energy applications.

17.
Cureus ; 15(7): e41692, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37575783

RESUMO

Background Adenoid hypertrophy is a common condition that can cause upper airway obstruction in children and adolescents, leading to various complications, including dental and maxillofacial abnormalities. However, parents may have limited knowledge of the orthodontic complications associated with this condition. Objective This study aimed to assess the knowledge and attitude of parents toward the orthodontic complications of untreated adenoid hypertrophy and to promote their awareness about this problem. Method This descriptive cross-sectional study involved 824 parents from all regions of Saudi Arabia. An online questionnaire was used to collect data on parents' demographics, their children's information, and their general knowledge about adenoid hypertrophy, including its symptoms, complications, and treatment. Results The study included 824 parents with a mean age of 36.78 ± 10.87 years, 73.2% of whom were women. Overall, only 6.2% (51.1 parents) had a good level of knowledge about adenoid hypertrophy. Conclusion The study highlights the importance of promoting awareness and educating parents about the orthodontic complications associated with adenoid hypertrophy. Greater awareness and understanding can help parents make better decisions for their children's health and well-being.

18.
Int J Biol Macromol ; 247: 125708, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37414323

RESUMO

Heavy metals and dyes used in technological applications have a detrimental influence on human health and the environment. The most used methods for removing pollutants depend on high-cost materials. Therefore, this research was conducted on cost-effective alternatives derived from natural resources and food waste. Herein, we designed a composite hydrogel based on sodium alginate/coffee waste (Alg/coffee) as adsorbent for the removal of organic and inorganic pollutants from aquatic solutions. The selectivity study displayed that Alg/coffee is more effective in adsorbing Pb(II) and acridine orange dye (AO). Adsorption of Pb(II) and AO was studied at concentration range of 0-170 mgL-1 and 0-40 mgL-1. Adsorption data of Pb(II) and AO reveals their fitting to Langmuir-isotherm and pseudo-second-order-kinetic models. The findings demonstrated that Alg/coffee hydrogel are more effective than coffee powder itself with an adsorption (%) approaching 98.44 % of Pb(II) and 80.53 % of AO. Real sample analysis reveals the efficiency of Alg/coffee hydrogel beads in Pb(II) adsorption. The adsorption cycle was examined four times providing high efficiency toward Pb(II) and AO. Desorption of Pb(II) and AO was easily performed using HCl eluent. Thus, Alg/coffee hydrogel beads could be promising adsorbent for the removal of organic and inorganic pollutants.


Assuntos
Poluentes Ambientais , Metais Pesados , Eliminação de Resíduos , Poluentes Químicos da Água , Humanos , Café , Adsorção , Alginatos , Hidrogéis , Alimentos , Chumbo , Corantes , Cinética , Concentração de Íons de Hidrogênio
19.
Cardiol Res ; 14(3): 201-210, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37304918

RESUMO

Background: Differences in clinical presentation and therapy outcomes between heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF) have been reported but described mainly among hospitalized patients. Because the population of outpatients with heart failure (HF) is increasing, we sought to discriminate the clinical presentation and responses to medical therapy in ambulatory patients with new-onset HFpEF vs. HFrEF. Methods: We retrospectively included all patients with new-onset HF treated at a single HF clinic in the past 4 years. Clinical data and electrocardiography (ECG) and echocardiography findings were recorded. Patients were followed up once weekly, and treatment response was evaluated according to symptoms resolution within 30 days. Univariate and multivariate regression analyses were performed. Results: A total of 146 patients were diagnosed with new-onset HF: 68 with HFpEF and 78 with HFrEF. The patients with HFrEF were older than those with HFpEF (66.9 vs. 62 years, respectively, P = 0.008). Patients with HFrEF were more likely to have coronary artery disease, atrial fibrillation, or valvular heart disease than those with HFpEF (P < 0.05 for all). Patients with HFrEF rather than HFpEF were more likely to present with New York Heart Association class 3 - 4 dyspnea, orthopnea, paroxysmal nocturnal dyspnea or low cardiac output (P < 0.007 for all). Patients with HFpEF were more likely than those with HFpEF to have normal ECG at presentation (P < 0.001), and left bundle branch block (LBBB) was observed only in patients with HFrEF (P < 0.001). Resolution of symptoms within 30 days occurred in 75% of patients with HFpEF and 40% of patients with HFrEF (P < 0.001). Conclusions: Ambulatory patients with new-onset HFrEF were older, and had higher incidence of structural heart disease, in comparison to those with new-onset HFpEF. Patients presenting with HFrEF had more severe functional symptoms than those with HFpEF. Patients with HFpEF were more likely than those with HFpEF to have normal ECG at the time of presentation, and LBBB was strongly associated with HFrEF. Outpatients with HFrEF rather than HFpEF were less likely to respond to treatment.

20.
Chemistry ; 29(40): e202301259, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37196153

RESUMO

Herein, we report the catalytic activity of a series of platinum(II) pre-catalysts, bearing N-heterocyclic carbene (NHC) ligands, in the alkene hydrosilylation reaction. Their structural and electronic properties are fully investigated using X-ray diffraction analysis and nuclear magnetic resonance spectroscopy (NMR). Next, our study presents a structure-activity relationship within this group of pre-catalysts and gives mechanistic insights into the catalyst activation step. An exceptional catalytic performance of one of the complexes is observed, reaching a turnover number (TON) of 970 000 and a turnover frequency (TOF) of 40 417 h-1 at 1 ppm catalyst loading. Finally, an attractive solvent-free and open-to-air alkene hydrosilylation protocol, featuring efficient platinum removal (reduction of residual Pt from 582 ppm to 5.8 ppm), is disclosed.

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