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1.
Sci Rep ; 14(1): 20074, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39209952

RESUMO

Textile dyes are frequently disposable in aqueous effluents, making it difficult to remove them from industrial effluents before their release to natural waters. This paper deals with the fabrication of cellulose-based adsorbents by reacting nanocelulose crystalline (nanocel) with N-[3-(trimethoxysilyl)propyl]ethylenediamine (TMSPEDA), forming the hybrid (silylpropyl)ethylenediamine@nanocellulose (SPEDA@nanocel), which was employed as adsorbent for the uptake of reactive yellow 2 dye (RY-2) from aqueous effluents. Characterisation of SPEDA@nanocel was carried out using FTIR, SEM-EDS, XRD, TGA, surface area, pHpzc, and hydrophobicity/hydrophilicity ratio (HI). Also, adsorption studies were thoroughly investigated. The effect of initial pH indicated that the maximum uptake of RY-2 takes place at pH 2, which is an indication of the electrostatic mechanism. The kinetic data carried out with 250 and 500 mg L-1 RY-2 with SPEDA@nanocel followed better the nonlinear fractional-like pseudo-first-order model. The t0.5 and t0.95 for the dye uptake were about 30 and 141 min, respectively. The equilibrium data from 10 to 45 °C indicated that the Liu isotherm model was the best-fitted isothermal model. The maximum sorption capacity attained was 112.3 mg g-1 at 45 °C. The thermodynamic data have shown that the equilibrium was favorable and endothermic, and the ΔH° was compatible with an electrostatic attraction between RY-2 and SPEDA@nanocel. Experiments of desorption of loaded adsorbent showed promising results for real applications since at least 5 adsorption/desorption cycles could be employed without significant changes in the recovery and with high precision.

2.
Children (Basel) ; 11(7)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39062280

RESUMO

Van Wyk-Grumbach syndrome (VWGS) refers to the development of peripheral precocious puberty, long-standing hypothyroidism, and gonadal masses; when not diagnosed, an unnecessary gonadectomy may be performed. Herein, we present a case of a 10-year-old girl with Down's syndrome, short stature, and vitiligo who presented to our hospital with vaginal bleeding and a palpable pelvic mass. Upon ultrasound and topographical examination, bilateral ovarian masses with negative tumor markers were detected. After bilateral gonadectomy, endocrine studies revealed profound hypothyroidism and peripheral puberty that led to the VWGS syndrome diagnosis (TSH 367.3 mUI/mL, isolated menstruation, indetectable LH, and elevated estradiol). Levothyroxine treatment improved obesity and short stature, and sexual hormone replacement began at 13 years of age. The literature on Van Wyk-Grumbach syndrome shows that it presents most often in women, and classic hypothyroidism symptoms always precede the diagnosis. Approximately 11% of patients have Down's syndrome, sometimes tumor markers are elevated, and some develop severe symptoms (myopathy, short stature, mental delay, ascites, pericardial effusion, Cullen's sign, pituitary hyperplasia, and severe anemia) that respond to levothyroxine treatment. Conclusions: Children with peripheral precocious puberty and gonadal masses must be studied for hypothyroidism before any radical decision is made.

3.
Mol Genet Genomic Med ; 12(5): e2451, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760995

RESUMO

BACKGROUND: Ellis-van Creveld syndrome (EvCS) is a chondroectodermal dysplasia caused by germline pathogenic variants in ciliary complex subunit 1 and 2 genes (EVC, EVC2) on chromosome 4p16.2. This disease has a broad phenotype, and there are few described phenotype-genotype correlations. METHODS: Ethical Compliance: Written informed consent was obtained from the parents. Here, we report a genetically confirmed Mexican patient with EvCS having two inherited pathogenic variants in trans in EVC2: c.[1195C>T];[2161delC]. RESULTS: This patient allowed a genotypic-phenotypic comparison with another Mexican subject who presented a more attenuated phenotype; furthermore, our patient also presented cleft palate, a rarely reported feature. CONCLUSION: Our case shows the importance of comparing functional hemizygosity between patient's phenotypes when they share a variant, and our case also supports the association of alterations in the palate as part of the EvCS phenotype.


Assuntos
Fissura Palatina , Síndrome de Ellis-Van Creveld , Fenótipo , Humanos , Fissura Palatina/genética , Fissura Palatina/patologia , Síndrome de Ellis-Van Creveld/genética , Síndrome de Ellis-Van Creveld/patologia , México , Masculino , Feminino , Peptídeos e Proteínas de Sinalização Intercelular
4.
Spec Care Dentist ; 44(1): 103-108, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37041105

RESUMO

INTRODUCTION: Ellis-van Creveld (EVC) syndrome is an autosomal recessive disorder predominantly characterized by a disproportionate dwarfism, ectodermal dysplasia, postaxial polydactyly, and congenital heart malformations and pulmonary hypoplasia. OBJECTIVE: In this article, we hereby present a case of a 6-year-old Brazilian boy with EVC syndrome who presented a rare oral lesion as well as a remarkable number of classical and uncommon oral and dental features. CASE REPORT: Clinical and radiographic examination revealed multiple enamel hypoplasia, teeth agenesis, conical teeth, lower canine rotation, bilateral posterior crossbite, taurodontism of deciduous and permanent molars and delayed tooth eruption, dental caries, and absent vestibular sulcus. Additionally, a whitish lobulated nodule located in the alveolar ridge in the anterior region of the mandible was noted. Anatomopathological examination was compatible with the diagnosis of peripheral odontogenic fibroma (POF). In a 10-month clinical follow-up, no signs of recurrence were observed. CONCLUSION: In view of the characteristic oral findings of EVC syndrome and the potential for recurrence of POF, the pediatric dentist plays an essential role in clinical follow-up, planning and preventive, and rehabilitative treatment.


Assuntos
Cárie Dentária , Síndrome de Ellis-Van Creveld , Fibroma , Anormalidades Dentárias , Masculino , Criança , Humanos , Síndrome de Ellis-Van Creveld/complicações , Síndrome de Ellis-Van Creveld/diagnóstico , Anormalidades Dentárias/diagnóstico por imagem , Anormalidades Dentárias/etiologia , Cavidade Pulpar , Fibroma/complicações
5.
Nano Lett ; 23(23): 11073-11081, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38019289

RESUMO

van der Waals heterostructures composed of two-dimensional (2D) transition metal dichalcogenides and vdW magnetic materials offer an intriguing platform to functionalize valley and excitonic properties in nonmagnetic TMDs. Here, we report magneto photoluminescence (PL) investigations of monolayer (ML) MoSe2 on the layered A-type antiferromagnetic (AFM) semiconductor CrSBr under different magnetic field orientations. Our results reveal a clear influence of the CrSBr magnetic order on the optical properties of MoSe2, such as an anomalous linear-polarization dependence, changes of the exciton/trion energies, a magnetic-field dependence of the PL intensities, and a valley g-factor with signatures of an asymmetric magnetic proximity interaction. Furthermore, first-principles calculations suggest that MoSe2/CrSBr forms a broken-gap (type-III) band alignment, facilitating charge transfer processes. The work establishes that antiferromagnetic-nonmagnetic interfaces can be used to control the valley and excitonic properties of TMDs, relevant for the development of opto-spintronics devices.

6.
ACS Appl Mater Interfaces ; 15(47): 54786-54796, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37967344

RESUMO

High-performance nanosized optoelectronic devices based on van der Waals (vdW) heterostructures have significant potential for use in a variety of applications. However, the investigation of nanoribbon-based vdW heterostructures are still mostly unexplored. In this study, based on first-principles calculations, we demonstrate that a Sb2S3/Sb2Se3 vdW heterostructure, which is formed by isostructural nanoribbons of stibnite (Sb2S3) and antimonselite (Sb2Se3), possesses a direct band gap with a typical type-II band alignment, which is suitable for optoelectronics and solar energy conversion. Optical absorption spectra show broad profiles in the visible and UV ranges for all of the studied configurations, indicating their suitability for photodevices. Additionally, in 1D nanoribbons, we see sharp peaks corresponding to strongly bound excitons in a fashion similar to that of other quasi-1D systems. The Sb2S3/Sb2Se3 heterostructure is predicted to exhibit a remarkable power conversion efficiency (PCE) of 28.2%, positioning it competitively alongside other extensively studied two-dimensional (2D) heterostructures.

7.
Chemphyschem ; 24(23): e202300387, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37675623

RESUMO

We present a detailed theoretical study of the molecular oxygen trimer where the potential energy surfaces of the seven multiplet states have been calculated by means of a pair approximation with very accurate dimer ab initio potentials. In order to obtain all the states a matrix representation of the potential using the uncoupled spin representation has been applied. The S = 0 ${S = 0}$ and S = 1 ${S = 1}$ states are nearly degenerate and low-lying isomers appear for most multiplicities. A crucial point in deciding the relative stabilities is the zero-point energy which represents a sizable fraction of the electronic well-depth. Therefore, we have performed accurate diffusion Monte Carlo studies of the lowest state in each multiplicity. Analysis of the wavefunction allows a deeper interpretation of the cluster structures, finding that they are significantly floppy in most cases.

8.
J Chromatogr A ; 1708: 464376, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37717451

RESUMO

The value of the concept of retention indices (RI) to the practice of gas chromatography (GC) is highlighted, where the RI of a compound is one component of the strategy to identify the compound. The widespread reliance on GC and then on mass spectrometry for 'identification', may result in inadequate confirmation of molecular identity. However, RI do provide a useful tentative indication of the possible molecule(s). Thus, the RI value is a useful first measure of the molecule identity, and shown here to be valuable provided limitations are recognised. An author has a responsibility to correctly calculate the index and then use the values for (tentative) identification. Tables of reference RI values are useful in this respect, but finding an 'exact match' RI value does not confirm the identity. Hence, it is necessary to understand how the RI value may be incorrectly used in this respect. The reviewer of written research is charged with ensuring the index values are applied in a rigorous manner. Selected case studies from our own work, support the care that must be exercised when reporting RI values. In terms of advanced GC operations, mention is made of multidimensional gas chromatography and comprehensive two-dimensional gas chromatography to acquire RI values on both the first and second columns in the two-column separation experiment.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas , Valores de Referência
9.
Genes (Basel) ; 14(4)2023 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-37107645

RESUMO

BACKGROUND: Ellis-van Creveld syndrome (EvCS) is an autosomal recessive ciliopathy with a disproportionate short stature, polydactyly, dystrophic nails, oral defects, and cardiac anomalies. It is caused by pathogenic variants in the EVC or EVC2 genes. To obtain further insight into the genetics of EvCS, we identified the genetic defect for the EVC2 gene in two Mexican patients. METHODS: Two Mexican families were enrolled in this study. Exome sequencing was applied in the probands to screen potential genetic variant(s), and then Sanger sequencing was used to identify the variant in the parents. Finally, a prediction of the three-dimensional structure of the mutant proteins was made. RESULTS: One patient has a compound heterozygous EVC2 mutation: a novel heterozygous variant c.519_519 + 1delinsT inherited from her mother, and a heterozygous variant c.2161delC (p.L721fs) inherited from her father. The second patient has a previously reported compound heterozygous EVC2 mutation: nonsense mutation c.645G > A (p.W215*) in exon 5 inherited from her mother, and c.273dup (p.K92fs) in exon 2 inherited from her father. In both cases, the diagnostic was Ellis-van Creveld syndrome. Three-dimensional modeling of the EVC2 protein showed that truncated proteins are produced in both patients due to the generation of premature stop codons. CONCLUSION: The identified novel heterozygous EVC2 variants, c.2161delC and c.519_519 + 1delinsT, were responsible for the Ellis-van Creveld syndrome in one of the Mexican patients. In the second Mexican patient, we identified a compound heterozygous variant, c.645G > A and c.273dup, responsible for EvCS. The findings in this study extend the EVC2 mutation spectrum and may provide new insights into the EVC2 causation and diagnosis with implications for genetic counseling and clinical management.


Assuntos
Síndrome de Ellis-Van Creveld , Proteínas de Membrana , Humanos , Feminino , Proteínas de Membrana/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Síndrome de Ellis-Van Creveld/genética , Síndrome de Ellis-Van Creveld/diagnóstico , Linhagem , Mutação , Códon sem Sentido
10.
Arq. bras. oftalmol ; Arq. bras. oftalmol;86(1): 52-59, Jan.-Feb. 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1403472

RESUMO

ABSTRACT Purpose: The purpose of this study was to evaluate the long-term outcomes of patients with trichiasis treated with a modified interlamellar oral mucosa graft surgery technique using fibrin glue. Methods: A prospective study was conducted at the Oculoplastic Department of Ouro Verde Hospital Complex. Patients with recurrent trichiasis without entropion who did not respond to conventional therapy, underwent intermarginal lamellar splitting of the eyelid and oral mucous graft insertion with fibrin glue replacing sutures. They were then evaluated at 1-day, 1-week, 1-month, 6-month, and 4-year follow-ups. Graft adherence, symptom resolution, esthetic satisfaction, overall patient satisfaction, and trichiasis recurrence were assessed at 6-month and 4-year follow-ups. Results: Fifteen patients (a total of 19 eyes) were included, of whom 10 (66.7%) were female and 5 (33.3%) were male. The mean age was 75.4 ± 10.5 years (range, 54-98 years). Acquired trichiasis was the main cause. Of the patients with acquired trichiasis, 12 (86.7%) had chronic blepharitis, 2 (13.3%) had an undetermined cause, and one (6.7%) had trachomatous trichiasis. Most cases involved only one eyelid segment (89.4%) and =5 lashes (84.2%; minor trichiasis). No adverse reactions from the fibrin glue were reported and no sutures were required after graft placement. At 6 months, no graft failures occurred, 17 eyes of 13 patients (89.4%) showed good graft adherence, 2 eyes of 2 patients (10.5%) showed partial graft adherence, and 2 eyes of 1 patient (10.5%) had trichiasis recurrence. At 4-year follow-up, no graft failure occurred, 3 patients (3 eyes) were lost to follow-up, and 2 eyes of 2 patients (14.2%) had trichiasis recurrence. The 4-year cumulative success rate was 78.9%. Conclusions: The modified interlamellar surgery with fibrin glue showed a good long-term success rate. This technique reduces surgical time, facilitates smaller graft insertion, and therefore, should be considered for recalcitrant minor trichiasis without entropion.>


RESUMO Objetivo: O objetivo deste estudo foi avaliar os resultados a longo prazo da técnica cirúrgica modificada de enxerto interlamelar de mucosa oral usando cola de fibrina para o tratamento de triquíase. Métodos: Um estudo prospectivo foi realizado no Departamento de Óculo-plástica do Complexo Hospital Ouro Verde. Pacientes com triquíase recorrente sem entrópio, que não responderam à terapia convencional, foram submetidos à cirurgia com separação intermarginal das lamelas das pálpebras e inserção de enxerto de mucosa oral usando cola de fibrina, substituindo a sutura. Pacientes foram avaliados 1 dia, 7 dias, 1 mês, 6 meses e 4 anos após a cirurgia. A aderência do enxerto, resolução dos sintomas, satisfação estética, satisfação geral do paciente e recorrência de triquíase foram avaliados aos 6 meses e aos 4 anos. Resultados: Quinze pacientes (total de 19 olhos) foram incluídos, dos quais 10 (66.7%) eram do sexo feminino e 5 (33.3%) do sexo masculino. A média de idade foi 75.4 ± 10.5 anos (intervalo 54-98 anos). Triquíase adquirida foi a principal causa, da qual 12 pacientes apresentaram blefarite crônica (86.7%), 2 pacientes com causa indeterminada (13.3%) e 1 paciente com triquíase tracomatosa (6.7%). A maioria dos casos envolveu apenas um segmento da pálpebra (89.4%) e com =5 cílios (84.2%; triquíase menor). Nenhuma reação adversa foi reportada com o uso da cola de fibrina e nenhum caso necessitou de sutura após inserção do enxerto. Aos 6 meses, não houve nenhuma falha de enxerto, 17 olhos de 13 pacientes (89.4%) apresentaram boa aderência de enxerto, 2 olhos de 2 pacientes (10.5%) mostraram aderência parcial do enxerto e 2 olhos de 1 paciente (10.5%) apresentaram recorrência da triquíase. Aos 4 anos, não houve nenhuma falha de enxerto, 3 olhos de 3 pacientes tiveram perda de seguimento e 2 olhos de 2 pacientes (14.2%) apresentaram recorrência da triquíase. A taxa de sucesso acumulativa após 4 anos foi de 78.9%. Conclusão: A cirurgia modificada de enxerto interlamelar de mucosa oral usando cola de fibrina mostrou uma boa taxa de sucesso a longo prazo. Esta técnica reduz o tempo cirúrgico, facilita a inserção de enxertos menores e, portanto, deve ser considerada em triquíase menor sem entrópio resistente ao tratamento convencional.


Assuntos
Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adesivo Tecidual de Fibrina , Mucosa Bucal , Adesivo Tecidual de Fibrina/uso terapêutico , Estudos Prospectivos
11.
Rev. odontopediatr. latinoam ; 13: 223592, 2023. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1435318

RESUMO

El síndrome de Ellis-van Creveld es un trastorno autosómico recesivo caracterizado por una tétrada de enanismo desproporcionado, displasia ectodérmica, polidactilia postaxial y malformaciones cardíacas congénitas. En este artículo, presentamos el caso de un niño brasileño de 6 años con síndrome de Ellis-van Creveld que presentó un número notable de características orales y dentales clásicas y hallazgos poco comunes como taurodontismo. El examen clínico reveló hipoplasia múltiple del esmalte, surco vestibular ausente, aserraduras alveolares en la región anterior del maxilar, dientes ausentes, dientes cónicos, canino inferior girado, mordida cruzada posterior bilateral, caries dental y un nódulo. Radiográficamente se observa agenesia dentaria, taurodontismo de molares primarios y permanentes y retraso en la erupción dentaria. Los hallazgos clínicos y radiográficos pueden estar presentes desde el nacimiento y el odontopediatra tiene un papel fundamental en el diagnóstico precoz del síndrome de Ellis-van Creveld, así como en la prevención de problemas orales, rehabilitación e intervenciones estéticas.


A síndrome de Ellis-van Creveld é uma doença autossômica recessiva caracterizada por uma tétrade de baixa estatura desproporcional, displasia ectodérmica, polidactilia pós-axial e malformações cardíacas congênitas. Neste artigo, será relatado um caso de um menino brasileiro de 6 anos de idade com síndrome de Ellis-van Creveld que apresenta um número notável de características orais e dentárias clássicas e achados incomuns como taurodontismo. Ao exame clínico foi revelado hipoplasia múltipla do esmalte, sulco vestibular ausente, serrilhas alveolares na maxila anterior, dentes ausentes, dentes cônicos, canino inferior rotacionado, mordida cruzada posterior bilateral, cárie dentária e um nódulo. Radiograficamente, foi observado agenesia dentária, taurodontismo de molares decíduos e permanentes e atraso na erupção dentária. Os achados clínicos e radiográficos podem estar presentes desde o nascimento e o odontopediatra tem papel fundamental no diagnóstico precoce da síndrome de Ellis-van Creveld, bem como na prevenção de problemas bucais, reabilitação e intervenções estéticas.


Ellis­van Creveld syndrome is an autosomal recessive disorder characterized by a tetrad of disproportionate dwarfism, ectodermal dysplasia, postaxial polydactyly, and congenital heart malformations. In this article, we hereby present a case of a 6-year-old Brazilian boy with Ellis­van Creveld syndrome who presented with a remarkable number of classical oral and dental features and uncommon findings such as taurodontism. Clinical examination revealed multiple enamel hypoplasia, absent vestibular sulcus, alveolar serrations in the maxilla anterior region, missing teeth, conical teeth, lower canine rotation, bilateral posterior crossbite, dental caries, and a nodule. Radiographically were observed teeth agenesis, taurodontism of deciduous and permanent molars, and delayed tooth eruption. Clinical and radiographic findings may be present from birth and the pediatric dentist has a fundamental role in the early diagnosis of Ellis­van Creveld syndrome, as well as oral problems prevention, rehabilitation, and aesthetic interventions.


Assuntos
Humanos , Masculino , Criança , Anormalidades Congênitas , Displasia Ectodérmica , Síndrome de Ellis-Van Creveld , Erupção Dentária , Cárie Dentária , Hipoplasia do Esmalte Dentário , Diagnóstico Precoce , Anodontia , Dente Molar
12.
Rev. biol. trop ; Rev. biol. trop;70(1)dic. 2022.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1407246

RESUMO

Abstract Introduction: The Loxicha Region of Oaxaca, Mexico, has been historically important for the study of Nymphalidae, second in the Papilionoidea for species richness. Describing the diversity patterns of this butterfly clade in Loxicha can improve our understanding of the evolutionary history of the Sierra Madre del Sur, the Mexican Pacific slope, and Mexico in general. Objective: To describe the temporal and spatial patterns of Nymphalidae diversity along an elevational gradient (80-2 600 m), and to compare Loxicha's fauna with other regions in Mexico. Methods: We obtained 28 756 records from 21 sites in the Loxicha Region, representing seven years of sampling. We estimate and analyze the diversity, endemism, and distributional patterns for three elevational levels and five vegetation types. We estimated species composition and similarity with other regions of the Pacific and Atlantic slopes. Results: We identified 189 taxa, including species and subspecies, from 85 genera and ten subfamilies of Nymphalidae. Loxicha contains 46 % of the species in the family recognized for Mexico, including ten endemic species and 56 endemic subspecies. Cloud forest and low elevations were the most diverse habitats for this family. There is a clear divergence between the Atlantic and Pacific faunas, and the Sierra Madre del Sur has two faunal components. High-elevation sites in Oaxaca, and in the neighboring state of Guerrero, have a distinctive fauna, apparently isolated from low-elevation sites, revealing an archipelagic distribution for cloud forest Nymphalidae. Conclusions: The Loxicha Region is one of the richest areas for Nymphalidae in Mexico. Distribution on the Pacific slope is determined by geographical history and ecological conditions, including elevation. Nymphalidae can be used to test hypotheses of biogeographic regionalization in Mexico.


Resumen Introducción: La Región Loxicha de Oaxaca, México, ha sido históricamente importante para el estudio de Nymphalidae, segunda en riqueza de especies en Papilionoidea. Describir los patrones de diversidad de este taxón de mariposas en Loxicha puede mejorar nuestra comprensión de la historia evolutiva de la Sierra Madre del Sur, la vertiente del Pacífico mexicano y México en general. Objetivo: Describir los patrones temporales y espaciales de la diversidad de Nymphalidae a lo largo de un gradiente altitudinal (80-2 600 m), y comparar la fauna de Loxicha con otras regiones de México. Métodos: Obtuvimos 28 756 registros de 21 sitios de la Región Loxicha, que representan siete años de muestreo. Estimamos y analizamos la diversidad, el endemismo y los patrones de distribución para tres niveles altitudinales y cinco tipos de vegetación. Estimamos la composición de especies y la similitud con otras regiones de las vertientes del Pacífico y Atlántico de México. Resultados: Identificamos 189 taxones, incluyendo especies y subespecies, de 85 géneros y diez subfamilias de Nymphalidae. Loxicha contiene 46 % de las especies de la familia reconocidas para México, incluidas diez especies endémicas y 56 subespecies endémicas. El bosque mesófilo y las elevaciones bajas fueron los hábitats más diversos para esta familia. Existe una clara divergencia entre las faunas del Atlántico y del Pacífico, y la Sierra Madre del Sur tiene dos componentes faunísticos. Los sitios de elevaciones altas en Oaxaca, y en el estado vecino de Guerrero, tienen una fauna distintiva, aparentemente aislada de los sitios de elevaciones bajas, lo que revela una distribución archipelágica para los Nymphalidae del bosque mesófilo. Conclusiones: La Región Loxicha es una de las zonas más diversas para Nymphalidae en México. La distribución en la vertiente del Pacífico está determinada por la historia geográfica y las condiciones ecológicas, incluida la elevación. Nymphalidae puede usarse para probar hipótesis de regionalización biogeográfica en México.


Assuntos
Animais , Lepidópteros/classificação , México
13.
Entropy (Basel) ; 24(11)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36421508

RESUMO

In this paper, we show an analysis of the global stability of a Curzon-Ahlborn engine considering that the working substance of the engine satisfies the Van der Waals equation of state, which is more general than the ideal gas case. We use the Lyapunov stability theory for the case where the engine operates at a maximum power output. We analyze the steady state of the intermediate temperatures as well as the asymptotic behavior of the performance of the engine. Additionally, we study the relationship between the inherent time delay by analyzing the dynamic properties of the system and the stability of the steady state. We present illustrative graphs of the obtained results. Finally, we include a brief discussion of the obtained results and appropriate conclusions.

14.
Nano Lett ; 22(21): 8641-8646, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36279205

RESUMO

We investigated the valley Zeeman splitting of excitonic peaks in the microphotoluminescence (µPL) spectra of high-quality hBN/WS2/MoSe2/hBN heterostructures under perpendicular magnetic fields up to 20 T. We identify two neutral exciton peaks in the µPL spectra; the lower-energy peak exhibits a reduced g-factor relative to that of the higher energy peak and much lower than the recently reported values for interlayer excitons in other van der Waals (vdW) heterostructures. We provide evidence that such a discernible g-factor stems from the spatial confinement of the exciton in the potential landscape created by the moiré pattern due to lattice mismatch or interlayer twist in heterobilayers. This renders magneto-µPL an important tool to reach a deeper understanding of the effect of moiré patterns on excitonic confinement in vdW heterostructures.

15.
Entropy (Basel) ; 24(8)2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-36010732

RESUMO

The notion of statistical order derives from the disequilibrium concept introduced by López-Ruiz, Mancini, and Calbet thirty years ago. In this effort, it is shown that the disequilibrium is intimately linked to the celebrated Rényi entropy. One also explores this link in connection with the van der Waals gas description.

16.
Proc (Bayl Univ Med Cent) ; 35(4): 569-571, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754571

RESUMO

The Van Wyk-Grumbach syndrome (VWGS) is characterized by severe hypothyroidism, peripheral precocious puberty, delayed bone age, hyperestrogenism, prepubertal luteinizing hormone, and elevated follicle-stimulating hormone. Patients with Down syndrome have a high susceptibility and prevalence of thyroid disorders. However, the coexistence of VWGS and trisomy 21 is uncommon. We present a case of a 5-year-old Mexican girl with Down syndrome, severe autoimmune hypothyroidism, pituitary enlargement, hyperprolactinemia, peripheral precocious puberty, multiple ovarian cysts, and delayed bone age, with a clinical diagnosis of VWGS. The patient presented with a remission of these manifestations after treatment with levothyroxine. Patients with Down syndrome, precocious puberty, hyperestrogenism, prepuberal luteinizing hormone, high follicle-stimulating hormone, and delayed bone age should be evaluated with a thyroid profile due to the possibility of VWGS.

17.
Entropy (Basel) ; 24(2)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35205477

RESUMO

We undertake a van der Waals inquiry at very low temperatures so as to find signs of a classical-quantum frontier. We investigate the relation of such signs with the celebrated van der Waals gas-liquid transition. We specialize the discussion with respect to the noble gases. For such purpose, we use rather novel thermal statistical quantifiers such as the disequilibrium, the statistical complexity, and the thermal efficiency. Fruitful insights are thereby gained.

18.
Membranes (Basel) ; 12(2)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35207151

RESUMO

Phytate is the main form of phosphorus in corn ethanol coproducts and poses digestion issues in monogastric-animal feed. Extracting phytate as a commodity chemical will bring extra revenue to the corn ethanol industry and reduces potential phosphorus pollution from livestock waste management. We assessed a simplified scale-up approach of an ion-exchange separation system applied to extract phytate from thin stillage using volumetric parameters and simplifications of the van Deemter model. Thin stillage is one of the main byproducts generated on dry-grind corn-to-ethanol plants and accounts for the liquid portion of the bottom product generated in the ethanol distillation process. Thin stillage is rich in dissolved phytate, which served as the basis for an ion-exchange extraction system developed with a scalability factor of 50. Under the evaluated conditions, similar breakthrough profiles were obtained when similar Péclet and Stanton numbers were maintained for the scales studied, demonstrating that a simple and straightforward scale-up can be attained if special attention is given to maintaining both parameters as the basis of calculations of the plate numbers of ion-exchange columns.

19.
Biosci. j. (Online) ; 38: e38031, Jan.-Dec. 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1395453

RESUMO

Semiarid regions are characterised by water scarcity, a limiting factor on plant growth and development. The Sertão Canal was built in the semiarid region of Brazil, more specifically in the state of Alagoas, with the aim of making year-round irrigation possible. However, for the best water management, a physical and hydrological knowledge of the soils is necessary. As such, the aim of this study was to determine the physical and hydrological characteristics of three different types of soil (Argisol, Quartzarenic Neossol and Regolithic Neossol) under native vegetation (Caatinga) and agricultural systems in the semiarid region of Alagoas, as well as to adjust the soil water retention characteristic curves. Soil samples were collected at depths of 0-10, 10-20 and 20-30 cm in the municipalities of Inhapi, Delmiro Gouveia and Pariconha, in the state of Alagoas. The points of the moisture characteristic curve were determined by the Richards method, at pressures of 33, 100, 500, 1000 and 1500 kPa. Retention curves were modelled using the exponential decay equation and compared using the van Genuchten equation, modelled with the help of the RETC computer software. Particle size varied according to the textural classification of the different soils, from Sand to a Sandy Clay Loam. The retention curve fluctuated due to the particle size of the soil, with the Red-Yellow Argisol (Inhapi) having a greater capacity for water retention. Extremely sandy soils, such as those in the Delmiro Gouveia region, had a low capacity for retaining water. For each soil sample, the exponential decay equation gave the best fit, with values for R2adjust of greater than 0.93. When the measured soil moisture levels were compared with the levels estimated by the RETC model, some of the treatments were unable to estimate accurately the moisture levels obtained with the soil water retention curves.


Assuntos
Características do Solo , Bacias Hidrográficas , Umidade do Solo
20.
Ciênc. rural (Online) ; 52(4): e20210357, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339676

RESUMO

Crop residues decomposition are controlled by chemical tissue components. This study evaluated changes on plant tissue components, separated by the Van Soest partitioning method, during cover crop decomposition. The Van Soest soluble fraction was the first to be released from the crop residues, followed by cellulose and hemicellulose. Lignin was the crop residue component that suffered the least degradation, and for certain crop residue types, lignin degradation was not detected. The degradation of the main components of crop residues (soluble fraction, cellulose, hemicellulose and lignin) is determined by the chemical and structural composition of each fraction.


A decomposição de resíduos culturais é controlada pela composição química do tecido vegetal. O objetivo deste estudo foi avaliar as alterações que ocorrem nos componentes do tecido vegetal, separados pelo fracionamento de Van Soest, durante a decomposição de plantas de cobertura. A fração solúvel foi a primeira a ser liberada dos resíduos culturais, seguida pela celulose e hemicelulose. A lignina foi o componente dos resíduos culturais de menor degradação, sendo que em alguns resíduos culturais não foi possível detectar a degradação deste componente. A degradação dos principais componentes dos resíduos culturais (fração solúvel, celulose, hemicelulose e lignina) é determinada pela composição química e estrutural de cada uma destas frações.


Assuntos
Resíduos/análise , Madeira/química , Celulose/química , Lignina/química
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