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1.
Chem Sci ; 15(22): 8472-8477, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38846380

RESUMO

The reaction of [Rh{(E)-CF[double bond, length as m-dash]CHCF3}(PEt3)3] with Zn(CH3)2 results in the methylation of the alkenyl ligand to give [Rh{(E/Z)-C(CH3)[double bond, length as m-dash]CHCF3}(PEt3)3]. Variable temperature NMR studies allowed the identification of a heterobinuclear rhodium-zinc complex as an intermediate, for which the structure [Rh(CH3)(ZnCH3){(Z)-C(CH3)[double bond, length as m-dash]CHCF3}(PEt3)2] is proposed. Based on these stoichiometric reactions, unique Negishi-type catalytic cross-coupling reactions of fluorinated propenes by consecutive C-H and C-F bond activation steps at room temperature were developed. The C-H bond activation steps provide a fluorinated ligand at Rh and deliver the fluorinated product, whereas the C-F bond activation and C-C coupling occur via outer-sphere nucleophilic attack at the fluorinated alkenyl ligand.

2.
Arch Cardiol Mex ; 94(1): 86-94, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38507315

RESUMO

BACKGROUND: Virtual consultations have increased exponentially, but a limitation is the inability to assess vital signs (VS). This is particularly useful in patients with heart failure (HF) for titrating prognosis-modifying medication. This issue could potentially be addressed by a tool capable of measuring blood pressure (BP) and heart rate (HR) accurately, remotely, and conveniently. Mobile phones equipped with transdermal optical imaging technology could meet these requirements. OBJECTIVE: To evaluate the accuracy of a transdermal optical imaging-based app for estimating VS compared to clinical assessment in patients with HF. METHODS: A prospective cohort study included patients evaluated in an HF outpatient unit between February and April 2022. BP and HR were simultaneously assessed using the app and clinical examination (BP with an automated sphygmomanometer and HR by brachial palpation). Three measurements were taken by both the app and clinic for each patient, by two independent blinded physicians. RESULTS: Thirty patients were included, with 540 measurements of BP and HR. The mean age was 66 (± 13) years, 53.3% were male. The mean left ventricular ejection fraction was 37 ± 15, with 63.3% having previous hospitalizations for HF, and 63.4% in NYHA class II-III. The mean difference between the app measurement and its clinical reference measurement was 3.6 ± 0.5 mmHg for systolic BP (SBP), 0.9 ± -0.2 mmHg for diastolic BP (DBP), and 0.2 ± 0.4 bpm for HR. When averaging the paired mean differences for each patient, the mean across the 30 patients was 2 ± 6 mmHg for SBP, -0.14 ± 4.6 mmHg for DBP, and 0.23 ± 4 bpm for HR. CONCLUSION: The estimation of BP and HR by an app with transdermal optical imaging technology was comparable to non-invasive measurement in patients with HF and met the precision criteria for BP measurement in this preliminary study. The use of this new transdermal optical imaging technology provides promising data, which should be corroborated in larger cohorts.


ANTECEDENTES: Las consultas virtuales aumentaron exponencialmente, pero presentan como limitación la imposibilidad de valorar los signos vitales (SV), siendo especialmente útiles en los pacientes con insuficiencia cardiaca (IC) para titular medicación que modifica pronóstico. Este problema podría potencialmente solucionarse mediante una herramienta que pueda medir la presión arterial (PA) y frecuencia cardiaca (FC) de manera precisa, accesible y remota. Los teléfonos móviles equipados con tecnología de imágenes ópticas transdérmicas podrían cumplir con estos requisitos. OBJETIVO: Evaluar la precisión de una app basada en imagen óptica transdérmica para estimar SV en relación con la valoración clínica en pacientes con IC. MÉTODOS: Estudio de cohorte prospectivo, se incluyeron pacientes evaluados en una unidad ambulatoria de IC de febrero a abril del 2022. Se valoró simultáneamente la PA y FC mediante la app y el examen clínico (PA con un esfigmomanómetro automatizado y FC por palpación braquial). Se realizaron tres mediciones por app y clínica en cada paciente, por dos médicos independientes, encontrándose ciegos a los resultados. RESULTADOS: Se incluyeron 30 pacientes, con 540 mediciones de TA y de FC. Edad media de 66 (± 13) años, el 53.3% de sexo masculino. La fracción de eyección del ventrículo izquierdo media fue de 37 ± 15, con hospitalizaciones previas por IC el 63.3%, en CF II-III el 63.4%. La diferencia media entre la medición de la app y su medición de referencia clínica fue de 3.6 ± 0.5 mmHg para PA sistólica (PAS), 0.9 ± ­0.2 mmHg para PA diastólica (PAD) y 0.2 ± 0.4 lpm para FC. Cuando se promedian las diferencias medias emparejadas para cada paciente, la media entre los 30 pacientes es de 2 ± 6 mmHg para PAS, ­0.14 ± 4.6 mmHg para PAD y 0.23 ± 4 lpm para FC. CONCLUSIÓN: La estimación de PA y FC por una app con tecnología de imagen óptica transdérmica fue comparable a la medición no invasiva en pacientes con IC, y cumple los criterios de precisión de la medición de PA en este estudio preliminar. La utilización de esta nueva tecnología de imagen óptica transdérmica brinda datos prometedores, que deberán ser corroborados en cohortes de mayor tamaño.


Assuntos
Insuficiência Cardíaca , Aplicativos Móveis , Humanos , Masculino , Idoso , Feminino , Volume Sistólico , Estudos Prospectivos , Função Ventricular Esquerda , Pressão Sanguínea/fisiologia
3.
Arch. cardiol. Méx ; 94(1): 86-94, ene.-mar. 2024. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1556897

RESUMO

Resumen Antecedentes: Las consultas virtuales aumentaron exponencialmente, pero presentan como limitación la imposibilidad de valorar los signos vitales (SV), siendo especialmente útiles en los pacientes con insuficiencia cardiaca (IC) para titular medicación que modifica pronóstico. Este problema podría potencialmente solucionarse mediante una herramienta que pueda medir la presión arterial (PA) y frecuencia cardiaca (FC) de manera precisa, accesible y remota. Los teléfonos móviles equipados con tecnología de imágenes ópticas transdérmicas podrían cumplir con estos requisitos. Objetivo: Evaluar la precisión de una app basada en imagen óptica transdérmica para estimar SV en relación con la valoración clínica en pacientes con IC. Métodos: Estudio de cohorte prospectivo, se incluyeron pacientes evaluados en una unidad ambulatoria de IC de febrero a abril del 2022. Se valoró simultáneamente la PA y FC mediante la app y el examen clínico (PA con un esfigmomanómetro automatizado y FC por palpación braquial). Se realizaron tres mediciones por app y clínica en cada paciente, por dos médicos independientes, encontrándose ciegos a los resultados. Resultados: Se incluyeron 30 pacientes, con 540 mediciones de TA y de FC. Edad media de 66 (± 13) años, el 53.3% de sexo masculino. La fracción de eyección del ventrículo izquierdo media fue de 37 ± 15, con hospitalizaciones previas por IC el 63.3%, en CF II-III el 63.4%. La diferencia media entre la medición de la app y su medición de referencia clínica fue de 3.6 ± 0.5 mmHg para PA sistólica (PAS), 0.9 ± -0.2 mmHg para PA diastólica (PAD) y 0.2 ± 0.4 lpm para FC. Cuando se promedian las diferencias medias emparejadas para cada paciente, la media entre los 30 pacientes es de 2 ± 6 mmHg para PAS, -0.14 ± 4.6 mmHg para PAD y 0.23 ± 4 lpm para FC. Conclusión: La estimación de PA y FC por una app con tecnología de imagen óptica transdérmica fue comparable a la medición no invasiva en pacientes con IC, y cumple los criterios de precisión de la medición de PA en este estudio preliminar. La utilización de esta nueva tecnología de imagen óptica transdérmica brinda datos prometedores, que deberán ser corroborados en cohortes de mayor tamaño.


Abstract Background: Virtual consultations have increased exponentially, but a limitation is the inability to assess vital signs (VS). This is particularly useful in patients with heart failure (HF) for titrating prognosis-modifying medication. This issue could potentially be addressed by a tool capable of measuring blood pressure (BP) and heart rate (HR) accurately, remotely, and conveniently. Mobile phones equipped with transdermal optical imaging technology could meet these requirements. Objective: To evaluate the accuracy of a transdermal optical imaging-based app for estimating VS compared to clinical assessment in patients with HF. Methods: A prospective cohort study included patients evaluated in an HF outpatient unit between February and April 2022. BP and HR were simultaneously assessed using the app and clinical examination (BP with an automated sphygmomanometer and HR by brachial palpation). Three measurements were taken by both the app and clinic for each patient, by two independent blinded physicians. Results: Thirty patients were included, with 540 measurements of BP and HR. The mean age was 66 (± 13) years, 53.3% were male. The mean left ventricular ejection fraction was 37 ± 15, with 63.3% having previous hospitalizations for HF, and 63.4% in NYHA class II-III. The mean difference between the app measurement and its clinical reference measurement was 3.6 ± 0.5 mmHg for systolic BP (SBP), 0.9 ± -0.2 mmHg for diastolic BP (DBP), and 0.2 ± 0.4 bpm for HR. When averaging the paired mean differences for each patient, the mean across the 30 patients was 2 ± 6 mmHg for SBP, -0.14 ± 4.6 mmHg for DBP, and 0.23 ± 4 bpm for HR. Conclusion: The estimation of BP and HR by an app with transdermal optical imaging technology was comparable to non-invasive measurement in patients with HF and met the precision criteria for BP measurement in this preliminary study. The use of this new transdermal optical imaging technology provides promising data, which should be corroborated in larger cohorts.

4.
Chirality ; 36(1): e23624, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37823399

RESUMO

Chiroptical responses are valuable for the structural determination of dissymmetric molecules. However, the development of everyday applications based on chiroptical systems is yet to come. We have been earlier using axially chiral allenes for the construction of linear, cyclic, and cage-shaped molecules that present remarkable chiroptical responses. Additionally, we have developed chiral surfaces through upstanding chiral architectures. Since the goal is to obtain robust chiroptical materials, more recently we have been studying spirobifluorenes (SBFs), a well-established building block in optoelectronic applications. After theoretical and experimental demonstration, the suitability of chiral SBFs for the development of robust chiroptical systems was certified by the construction all-carbon double helices, flexible shape-persistent macrocycles, chiral frameworks for surface functionalization, and structures featuring helical or spiroconjugated molecular orbitals. Here, we give an overview of our contribution to these matters.

6.
Molecules ; 28(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37894636

RESUMO

Organic amines are important compounds present in a wide variety of products, which makes the development of new systems for their detection an interesting field of study. New organometallic complexes of group 9 [MCp*X(2'-R-2-py-SBF)] (M = Ir, Rh; R = H, X = Cl (6), R = H, X = OAc (7), R = CHO, X = Cl (8)), and [IrCp*Cl(2', 7-diCHO-2-py-SBF)] (9) (Cp* pentamethylcyclopentadienyl, SBF = 9,9'-spirobifluorene) bearing bidentate C-N ligands based on 9,9'-spirobifluorene were obtained and characterized by NMR spectroscopy, mass spectrometry, IR spectroscopy, and X-ray diffraction analysis when possible. The formation of a Schiff base to give complexes with the formula [MCp*Cl(2'-CH=NR-2-py-SBF)] (M = Ir, Rh; R = alkyl or aryl (10-12)), through condensation of an amine, and the aldehyde group present in these new complexes was studied leading to a selective reactivity depending on the nature of the amine and the metal center. While the iridium complexes only react with aromatic amines, the rhodium derivative requires heat for those but can react at room temperature with aliphatic amines.

7.
Eur J Pediatr Surg ; 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37473779

RESUMO

INTRODUCTION: Despite advances in neonatal intensive care, fetuses with congenital diaphragmatic hernia (CDH) remain to have a poor prognosis. Exclusive postnatal treatment is inadequate in patients with moderate CDH (observed than expected lung-to-head ratio [O/E LHR] 26-45%) and can lead to respiratory failure at birth, requiring extracorporeal membrane oxygenation in 75% of cases. An ex-utero intrapartum treatment (EXIT) procedure may be beneficial in these cases, improving the fetal-neonatal transition. MATERIAL AND METHODS: We review all pregnancies with fetal isolated left CDH with moderate O/E LHR delivered by EXIT in our center from January 2007 to December 2022. Maternal and neonatal variables were analyzed. As primary outcomes, we included neonatal survival and mortality rates, surgical and infectious complications, uterine scar dehiscence, and blood loss during EXIT. As secondary outcomes, we studied recurrences of the diaphragmatic defect, long-term evolution, subsequent pregnancies, and mode of delivery. RESULTS: A total of 14 patients were delivered by the EXIT procedure, with a neonatal survival rate of 85.7%. All these children had optimal physical and neurocognitive development and no pulmonary morbidity. We found no major complications and 7.1% of minor maternal complications. There were no cases of surgical wound infection or endometritis. The median decrease in hemoglobin during the EXIT procedure was 1.9 mg/dL, and only one case required postoperative transfusion. Two out of the 14 women became pregnant again, and both pregnancies were uneventful. CONCLUSIONS: In our series, the EXIT procedure allows for adequate airway management associated with a high neonatal survival rate in patients with moderate O/E LHR CDH, with a low rate of neonatal and maternal complications.

9.
New Phytol ; 238(2): 874-887, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36683441

RESUMO

Genetic divergence between species depends on reproductive isolation (RI) due to traits that reduce interspecific mating (prezygotic isolation) or are due to reduced hybrid fitness (postzygotic isolation). Previous research found that prezygotic barriers tend to be stronger than postzygotic barriers, but most studies are based on the evaluation of F1 hybrid fitness in early life cycle stages. We combined field and experimental data to determine the strength of 17 prezygotic and postzygotic reproductive barriers between two Lysimachia species that often co-occur and share pollinators. We assessed postzygotic barriers up to F2 hybrids and backcrosses. The two species showed near complete RI due to the cumulative effect of multiple barriers, with an uneven and asymmetric contribution to isolation. In allopatry, prezygotic barriers contributed more to reduce gene flow than postzygotic barriers, but their contributions were more similar in sympatry. The strength of postzygotic RI was up to three times lower for F1 progeny than for F2 or backcrossed progenies, and RI was only complete when late F1 stages and either F2 or backcrosses were accounted for. Our results thus suggest that the relative strength of postzygotic RI may be underestimated when its effects on late stages of the life cycle are disregarded.


Assuntos
Lysimachia , Isolamento Reprodutivo , Hibridização Genética , Reprodução , Fenótipo , Especiação Genética
10.
Dalton Trans ; 52(2): 487-493, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36504193

RESUMO

Three new spirobifluorene iridaaromatic compounds bearing electron-withdrawing or electron-donor substituents or another iridanaphthalene moiety have been synthesized and structurally characterized. Thorough experimental and theoretical evaluation revealed that these novel systems present a high thermal, air and electrochemical stability as well as low optical and electronic energy gap values with a significant redshift of the absorption maximum in the UV-Vis spectra and predicted remarkably higher first hyperpolarizabilities compared to their organic counterparts. Therefore, the combination of a metallaaromatic system with a spirobifluorene moiety leads to the design and development of new spirobifluorene derivatives. These new systems have shown interesting optical and electronic properties making them of interest for future applications in optoelectronics.

11.
Chempluschem ; 87(6): e202100554, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35415974

RESUMO

Spirobifluorenes are an important class of spiro compounds frequently used in the field of organic electronics. However, harnessing spiroconjugation to obtain high-performance in such structural motifs remains unexplored. We herein propose that peripheral functionalization may serve as a useful tool to control spiroconjugation in an ON/OFF manner on both chemical reactivity and photophysical properties. In particular, the ratio of mono- and di-functionalized spirobifluorenes found experimentally during their synthesis were found to be 3/2, 7/2, and 12/2 for phenyl, nitro-phenyl and amino-phenyl analogues, respectively. These remarkable reactivity differences correlate with the spiroconjugation character evaluated theoretically at the CAM-B3LYP/6-31G(d,p) level of theory. Additionally, comparison of experimental and predicted optical and chiroptical responses shows that spiroconjugated molecular orbitals have a significant or negligible involvement on the main electronic transitions depending on the peripheral functionality of the spirobifluorene.


Assuntos
Compostos de Espiro , Eletrônica , Compostos de Espiro/química
12.
Chem Sci ; 13(4): 1130-1135, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35211279

RESUMO

The hydrofluoroolefin Z-1,3,3,3-tetrafluoropropene has been activated via an initial C-F bond activation and subsequent C-H bond activation using [Rh(H)(PEt3)3] (1) or via C-H bond activation at [Rh(CH3)(PEt3)3] (8). In both cases the formation of [Rh{(E)-CF[double bond, length as m-dash]CHCF3}(PEt3)3] (3) was observed. Importantly, the C-F activation product [Rh{(E)-CH[double bond, length as m-dash]CHCF3}(PEt3)3] (2) reacts in the presence of Z-1,3,3,3-tetrafluoropropene into 3. The latter converted into [Rh(C[triple bond, length as m-dash]CCF3)(PEt3)3] (6) by an unprecedented dehydrofluorination reaction, presumably via a vinylidene complex as intermediate. When the carbonyl complex [Rh(C[triple bond, length as m-dash]CCF3)(CO)(PEt3)3] (12) was treated with an excess of NEt3·3HF or HBF4 at low temperature, the formation of the phosphonioalkenyl compounds [Rh{(Z)-C(PEt3)[double bond, length as m-dash]CHCF3}(CO)(PEt3)2]X (X = F(HF) x , BF4) (13) was observed. The formation of 13 can be explained by an attack of PEt3 at the electrophilic α-carbon atom of an intermediate vinylidene complex. The employment of PiPr3 derivatives as model compounds allowed for the isolation of the unique fluorido vinylidene complex trans-[Rh(F)([double bond, length as m-dash]C[double bond, length as m-dash]CHCF3)(PiPr3)2] (16), which in the presence of PEt3 transforms into [Rh(C[triple bond, length as m-dash]CCF3)(PEt3)3] (6).

13.
Anat Sci Educ ; 15(4): 719-730, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34008341

RESUMO

The utility of three-dimensional (3D) printed models for medical education in complex congenital heart disease (CHD) is sparse and limited. The purpose of this study was to evaluate the utility of 3D printed models for medical education in criss-cross hearts covering a wide range of participants with different levels of knowledge and experience, from medical students, clinical fellows up to senior medical personnel. Study participants were enrolled from four dedicated imaging workshops developed between 2016 and 2019. The study design was a non-randomized cross-over study to evaluate 127 participants' level of understanding of the criss-cross heart anatomy. This was evaluated using the scores obtained following teaching with conventional images (echocardiography and magnetic resonance imaging) versus a 3D printed model learning approach. A significant improvement in anatomical knowledge of criss-cross heart anatomy was observed when comparing conventional imaging test scores to 3D printed model tests [76.9% (61.5%-87.8%) vs. 84.6% (76.9%-96.2%), P < 0.001]. The increase in the questionnaire marks was statistically significant across all academic groups (consultants in pediatric cardiology, fellows in pediatric cardiology, and medical students). Ninety-four percent (120) and 95.2% (121) of the participants agreed or strongly agreed, respectively, that 3D models helped them to better understand the medical images. Participants scored their overall satisfaction with the 3D printed models as 9.1 out of 10 points. In complex CHD such as criss-cross hearts, 3D printed replicas improve the understanding of cardiovascular anatomy. They enhanced the teaching experience especially when approaching medical students.


Assuntos
Anatomia , Coração Entrecruzado , Educação Médica , Anatomia/educação , Criança , Educação Médica/métodos , Humanos , Imageamento Tridimensional/métodos , Modelos Anatômicos , Impressão Tridimensional , Tomografia Computadorizada por Raios X/métodos
14.
Cardiol Young ; 32(8): 1285-1288, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34602111

RESUMO

INTRODUCTION: Cardiopulmonary exercise test (CPET) allows quantification of functional capacity of patients with Fontan. The objective of this study was to determine the role of CPET parameters in predicting a higher maximum oxygen consumption (VO2 max) and to analyse the role of CPET parameters in predicting an unfavourable outcome. METHODS: A retrospective, cross-sectional, descriptive study was carried out on 57 patients with Fontan, who had undergone incremental CPET with cycloergometer between 2010 and 2020. Determinants of VO2 max and determinants of clinical deterioration were analysed. RESULTS: In the univariate analysis, the variables significantly related to VO2 max were: age, sex, body mass index (BMI), years of Fontan evolution, intracardiac Fontan, oxygen consumption at anaerobic threshold (VO2AT), CO2 equivalents at anaerobic threshold (VE/VCO2) and chronotropic insufficiency. The multiple linear regression model that best fitted the relationship between VO2 max and independent variables (correlation coefficient 0.73) included sex (correlation index 3.35; p = 0.02), BMI (-0.27; p = 0.02), chronotropic failure (-2.79; p = 0.01) and VO2AT (0.92; p < 0.0001). In the univariate analysis of the prognostic CPET variables related to an unfavourable clinical situation, significance was only obtained with chronotropic insufficiency (p = 0.003). In multivariate analysis, chronotropic insufficiency maintains its association [p= 0.017, OR = 4.65 (1.3-16.5)]. CONCLUSIONS: In conclusion, together with the anthropometric parameters universally related to VO2 max, chronotropic insufficiency and VO2AT are the main determinants of functional capacity in patients with Fontan. Moreover, chronotropic insufficiency is closely related to unfavourable clinical evolution. Our data would support the intensive treatment of chronotropic insufficiency in order to improve the quality of life and the clinical situation of patients with Fontan.


Assuntos
Teste de Esforço , Qualidade de Vida , Estudos Transversais , Humanos , Oxigênio , Consumo de Oxigênio , Prognóstico , Estudos Retrospectivos
15.
Chemistry ; 27(70): 17707-17712, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34634177

RESUMO

The electron-rich Pt complex [Pt(IMes)2 ] (IMes: [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolinylidine]) can be used as precursor for the syntheses of a variety of fluorido ligand containing compounds. The sulfur fluoride SF4 undergoes a rapid oxidative addition at Pt0 to yield trans-[Pt(F)(SF3 )(IMes)2 ]. A photolytic reaction of SF6 at [Pt(IMes)2 ] in the presence of IMes gave the fluorido complexes trans-[Pt(F)2 (IMes)2 ] and trans-[Pt(F)(SF3 )(IMes)2 ] along with trans-[Pt(F)(SOF)(IMes)2 ] and trans-[Pt(F)(IMes')(IMes)] (IMes': cyclometalated IMes ligand), the latter being products produced by reaction with adventitious water. trans-[Pt(F)(SOF)(IMes)2 ] and trans-[Pt(F)2 (IMes)2 ] were synthesized independently by treatment of [Pt(IMes)2 ] with SOF2 or XeF2 . A reaction of [Pt(IMes)2 ] with a HF source gave trans-[Pt(H)(F)(IMes)2 ], and an intermediate bifluorido complex trans-[Pt(H)(FHF)(IMes)2 ] was identified. Compound trans-[Pt(H)(F)(IMes)2 ] converts in the presence of CsF into trans-[Pt(F)(IMes')(IMes)].

16.
Dalton Trans ; 50(32): 11216-11220, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34338266

RESUMO

Polycyclic iridaaromatic compounds are of great interest not only because of the contributions made in "aromatic chemistry", but also because of the possibility of improving the results of the applications of the corresponding organic analogues in different fields. Therefore, understanding the requirements necessary to build on demand this type of compound with specific properties is of great importance. In this work, the keys to successfully synthesize iridaaromatic complexes via methoxyalkenylcarbenes are established. Experimental and theoretical results show (i) that bearing two aromatic substituents on the gamma carbon of the methoxyalkylcarbene promotes the C-H bond activation; (ii) the need for large steric hindrance of the second substituent for a selective synthesis and, (iii) the selectivity in the C-H bond activation towards the less sterically hindered system.

17.
BMC Cardiovasc Disord ; 21(1): 405, 2021 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418966

RESUMO

BACKGROUND: Malformation of the right atrium is a rare cardiac abnormality and is usually reported as isolated malformation in the literature. CASE PRESENTATION: Prenatal giant atrial dilatation in an asymptomatic infant was treated surgically at 18 months of age, due to potential risk of thrombosis and arrhythmias. Post-surgical echocardiographic images illustrate residual atrial elevated pressure. CONCLUSIONS: Sometimes, as seems in our case, right atrial dilatation hides an associated restrictive right ventricle.


Assuntos
Cardiomegalia/etiologia , Aneurisma Cardíaco/congênito , Átrios do Coração/anormalidades , Cardiopatias Congênitas/complicações , Função do Átrio Direito , Pressão Atrial , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/fisiopatologia , Cardiomegalia/cirurgia , Ecocardiografia , Feminino , Aneurisma Cardíaco/diagnóstico por imagem , Aneurisma Cardíaco/fisiopatologia , Aneurisma Cardíaco/cirurgia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Átrios do Coração/cirurgia , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Gravidez , Resultado do Tratamento , Ultrassonografia Pré-Natal , Função Ventricular Direita
18.
Molecules ; 26(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361807

RESUMO

This review describes the development of a versatile methodology to synthesize polycyclic metallaaromatic hydrocarbons based on iridium, as well as the studies that helped us to determine and understand what is required in order to broaden the scope and the selectivity of the methodology and stabilize the complexes obtained. This methodology aims to open the door to new materials based on graphene fragments.

19.
Chemistry ; 27(46): 11926-11934, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34118095

RESUMO

The reaction of the rhodium(I) complexes [Rh(E)(PEt3 )3 ] (E=GePh3 (1), H (6), F (7)) with 1,1,3,3,3-pentafluoropropene afforded the defluorinative germylation products Z/E-2-(triphenylgermyl)-1,3,3,3-tetrafluoropropene and the fluorido complex [Rh(F)(CF3 CHCF2 )(PEt3 )2 ] (2) together with the fluorophosphorane E-(CF3 )CH=CF(PFEt3 ). For [Rh(Si(OEt)3 )(PEt3 )3 ] (4) the coordination of the fluoroolefin was found to give [Rh{Si(OEt)3 }(CF3 CHCF2 )(PEt3 )2 ] (5). Two equivalents of complex 2 reacted further by C-F bond oxidative addition to yield [Rh(CF=CHCF3 )(PEt3 )2 (µ-F)3 Rh(CF3 CHCF2 )(PEt3 )] (9). The role of the fluorido ligand on the reactivity of complex 2 was assessed by comparison with the analogous chlorido complex. The use of complexes 1, 4 and 6 as catalysts for the derivatization of 1,1,3,3,3-pentafluoropropene provided products, which were generated by hydrodefluorination, hydrometallation and germylation reactions.

20.
Sensors (Basel) ; 21(4)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672874

RESUMO

The stability of power systems is very sensitive to voltage or current variations caused by the discontinuous supply of renewable power feeders. Moreover, the impact of these anomalies varies depending on the sensitivity/resilience of customer and transmission system equipment to those deviations. From any of these points of view, an instantaneous characterization of power quality (PQ) aspects becomes an important task. For this purpose, a wavelet-based power quality indices (PQIs) are introduced in this paper. An instantaneous disturbance index (ITD(t)) and a Global Disturbance Ratio index (GDR) are defined to integrally reflect the PQ level in Power Distribution Networks (PDN) under steady-state and/or transient conditions. With only these two indices it is possible to quantify the effects of non-stationary disturbances with high resolution and precision. These PQIs offer an advantage over other similar because of the suitable choice of mother wavelet function that permits to minimize leakage errors between wavelet levels. The wavelet-based algorithms which give rise to these PQIs can be implemented in smart sensors and used for monitoring purposes in PDN. The applicability of the proposed indices is validated by using a real-time experimental platform. In this emulated power system, signals are generated and real-time data are analyzed by a specifically designed software. The effectiveness of this method of detection and identification of disturbances has been proven by comparing the proposed PQIs with classical indices. The results confirm that the proposed method efficiently extracts the characteristics of each component from the multi-event test signals and thus clearly indicates the combined effect of these events through an accurate estimation of the PQIs.

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