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1.
Sci Rep ; 12(1): 8516, 2022 May 20.
Article in English | MEDLINE | ID: mdl-35595802

ABSTRACT

In this paper we investigate quasinormal modes (QNM) for a scalar field around a noncommutative Schwarzschild black hole. We verify the effect of noncommutativity on quasinormal frequencies by applying two procedures widely used in the literature. The first is the Wentzel-Kramers-Brillouin (WKB) approximation up to sixth order. In the second case we use the continuous fraction method developed by Leaver. Besides, we also show that due to noncommutativity, the shadow radius is reduced when we increase the noncommutative parameter. In addition, we find that the shadow radius is nonzero even at the zero mass limit for finite noncommutative parameter.

2.
Physica A ; 559: 125092, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32843818

ABSTRACT

We here propose to model active and cumulative cases data from COVID-19 by a continuous effective model based on a modified diffusion equation under Lifshitz scaling with a dynamic diffusion coefficient. The proposed model is rich enough to capture different aspects of a complex virus diffusion as humanity has been recently facing. The model being continuous it is bound to be solved analytically and/or numerically. So, we investigate two possible models where the diffusion coefficient associated with possible types of contamination are captured by some specific profiles. The active cases curves here derived were able to successfully describe the pandemic behavior of Germany and Spain. Moreover, we also predict some scenarios for the evolution of COVID-19 in Brazil. Furthermore, we depicted the cumulative cases curves of COVID-19, reproducing the spreading of the pandemic between the cities of São Paulo and São José dos Campos, Brazil. The scenarios also unveil how the lockdown measures can flatten the contamination curves. We can find the best profile of the diffusion coefficient that better fit the real data of pandemic.

3.
Genet Mol Res ; 15(4)2016 Dec 02.
Article in English | MEDLINE | ID: mdl-27966759

ABSTRACT

Myrcia lundiana Kiaersk. is a tree of the family Myrtaceae found in tropical and subtropical areas of the southern hemisphere that produces essential oil. The aim of this study was to characterize the genetic diversity of M. lundiana plants from a native population of Parque Nacional de Itabaiana, using inter-simple sequence repeat molecular markers. Thirty-five primers were tested, 20 of which were polymorphic, resulting in 135 polymorphic and informative bands. Results of the cluster analysis, obtained using the unweighted pair group method with arithmetic mean, grouped plants into three clusters: Cluster I - MLU001, MLU002, MLU003, MLU004, MLU005, MLU006, MLU018, MLU019, MLU020, MLU021, MLU022; MLU008, MLU011, MLU012, MLU014, MLU015, MLU017, MLU026, and MLU028; Cluster II - MLU007, MLU009, MLU010, MLU013, and MLU016; and Cluster III - MLU023, MLU024, MLU025, and MLU027. Jaccard similarity coefficients for pair-wise comparisons of plants ranged between 0.15 and 0.87. MLU014 and MLU015 presented low genetic diversity, with a similarity index of 0.87. Conversely, MLU007 and MLU019 presented high diversity, with a similarity index of 0.15. According to the structure analysis, three distinct clusters were formed. Genetic diversity of M. lundiana plants was intermediate, and expansion of its genetic diversity is necessary. MLU026 and MLU028 are the most suitable for selection in breeding programs, since they clearly represent all of the diversity present in these plants. Moreover, these results provide important information on the existing genetic variability, highlighting the importance of Parque Nacional de Itabaiana for the conservation of this species.


Subject(s)
Genetic Variation , Microsatellite Repeats , Myrtaceae/genetics , Cluster Analysis , Conservation of Natural Resources , DNA, Plant/genetics , Genetic Markers/genetics , Genetics, Population , Phylogeny , Plant Breeding
4.
Genet Mol Res ; 15(3)2016 Sep 02.
Article in English | MEDLINE | ID: mdl-27706706

ABSTRACT

Varronia curassavica Jacq. is a medicinal and aromatic plant from Brazil with significant economic importance. Studies on genetic diversity in active germplasm banks (AGB) are essential for conservation and breeding programs. The aim of this study was to analyze the genetic diversity of V. curassavica accessions of the AGB of Medicinal and Aromatic Plants of the Federal University of Sergipe (UFS), using inter-simple sequence repeat molecular markers. Twenty-four primers were tested, and 14 were polymorphic and informative, resulting in 149 bands with 97.98% polymorphism. The UPGMA dendrogram divided the accessions into Clusters I and II. Jaccard similarity coefficients for pair-wise comparisons of accessions ranged between 0.24 and 0.78. The pairs of accessions VCUR-001/VCUR-503, VCUR-001/VCUR-504, and VCUR-104/VCUR-501 showed relatively low similarity (0.24), and the pair of accessions VCUR-402/VCUR- 403 showed medium similarity (0.78). Twenty-eight accessions were divided into three distinct clusters, according to the STRUCTURE analysis. The genetic diversity of V. curassavica in the AGB of UFS is low to medium, and it requires expansion. Accession VCUR-802 is the most suitable for selection in breeding program of this species, since it clearly represents all of the diversity present in the AGB.


Subject(s)
Cordia/genetics , Microsatellite Repeats , Phylogeny , Polymorphism, Genetic , Cluster Analysis , Cordia/classification , DNA Primers , Genetic Markers , Plant Breeding , Plants, Medicinal
5.
Genet Mol Res ; 15(1)2016 Feb 19.
Article in English | MEDLINE | ID: mdl-26909987

ABSTRACT

Patchouli [Pogostemon cablin (Blanco) Benth.] is an aromatic, herbaceous plant belonging to the Lamiaceae family native to Southeast Asia. Its leaves produce an essential oil regularly used by the perfume and cosmetics industries. However, since patchouli from the Philippines and India were described and named Pogostemon patchouli, there has been a divergence in the identity of these species. The objective of the current study was to study the genetic diversity of patchouli accessions in the Active Germplasm Bank of Universidade Federal de Sergipe using microsatellite and inter simple sequence repeat markers. The results of both types of molecular markers showed that there are two well-defined clusters of accessions that harbor exclusive alleles. It was observed that these two clusters are genetically distant, suggesting that they belong to two different species. Based on the results, two accessions were classified as Pogostemon heyneanus and the remaining accessions were classified as P. cablin.


Subject(s)
Lamiaceae/genetics , Microsatellite Repeats , Phylogeny , Brazil , India , Lamiaceae/classification , Oils, Volatile/isolation & purification , Philippines , Phylogeography , Plant Leaves/chemistry , Plant Leaves/genetics , Seed Bank
6.
Braz J Med Biol Res ; 40(1): 105-15, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17225003

ABSTRACT

Myrtaceae is a plant family widely used in folk medicine and Syzygium and Eugenia are among the most important genera. We investigated the anti-allergic properties of an aqueous leaf extract of Syzygium cumini (L.) Skeels (SC). HPLC analysis revealed that hydrolyzable tannins and flavonoids are the major components of the extract. Oral administration of SC (25-100 mg/kg) in Swiss mice (20-25 g; N = 7/group) inhibited paw edema induced by compound 48/80 (50% inhibition, 100 mg/kg; P

Subject(s)
Anti-Allergic Agents/pharmacology , Edema/drug therapy , Histamine Release/drug effects , Pleurisy/drug therapy , Syzygium/chemistry , Animals , Anti-Allergic Agents/isolation & purification , Chromatography, High Pressure Liquid , Disease Models, Animal , Edema/chemically induced , Edema/immunology , Enzyme-Linked Immunosorbent Assay , Eosinophils/drug effects , Male , Mast Cells/drug effects , Mast Cells/immunology , Mice , Mice, Inbred BALB C , Peritoneal Cavity/cytology , Plant Extracts/pharmacology , Plant Leaves/chemistry , Pleurisy/chemically induced , Pleurisy/immunology , Rats , Rats, Wistar
7.
Braz. j. med. biol. res ; 40(1): 105-115, Jan. 2007. graf, tab
Article in English | LILACS | ID: lil-439665

ABSTRACT

Myrtaceae is a plant family widely used in folk medicine and Syzygium and Eugenia are among the most important genera. We investigated the anti-allergic properties of an aqueous leaf extract of Syzygium cumini (L.) Skeels (SC). HPLC analysis revealed that hydrolyzable tannins and flavonoids are the major components of the extract. Oral administration of SC (25-100 mg/kg) in Swiss mice (20-25 g; N = 7/group) inhibited paw edema induced by compound 48/80 (50 percent inhibition, 100 mg/kg; P <= 0.05) and, to a lesser extent, the allergic paw edema (23 percent inhibition, 100 mg/kg; P <= 0.05). SC treatment also inhibited the edema induced by histamine (58 percent inhibition; P <= 0.05) and 5-HT (52 percent inhibition; P <= 0.05) but had no effect on platelet-aggregating factor-induced paw edema. SC prevented mast cell degranulation and the consequent histamine release in Wistar rat (180-200 g; N = 7/group) peritoneal mast cells (50 percent inhibition, 1 æg/mL; P <= 0.05) induced by compound 48/80. Pre-treatment of BALB/c mice (18-20 g; N = 7/group) with 100 mg/kg of the extract significantly inhibited eosinophil accumulation in allergic pleurisy (from 7.662 ± 1.524 to 1.89 ± 0.336 x 10(6)/cavity; P <= 0.001). This effect was related to the inhibition of IL-5 (from 70.9 ± 25.2 to 12.05 ± 7.165 pg/mL) and CCL11/eotaxin levels (from 60.4 ± 8.54 to 32.8 ± 8.4 ng/mL) in pleural lavage fluid, using ELISA. These findings demonstrate an anti-allergic effect of SC, and indicate that its anti-edematogenic effect is due to the inhibition of mast cell degranulation and of histamine and serotonin effects, whereas the inhibition of eosinophil accumulation in the allergic pleurisy model is probably due to an impairment of CCL11/eotaxin and IL-5 production.


Subject(s)
Animals , Male , Mice , Rats , Anti-Allergic Agents/pharmacology , Edema/drug therapy , Eugenia/chemistry , Histamine Release/drug effects , Pleurisy/drug therapy , Anti-Allergic Agents/isolation & purification , Chromatography, High Pressure Liquid , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Edema/chemically induced , Edema/immunology , Eosinophils/drug effects , Mice, Inbred BALB C , Mast Cells/drug effects , Mast Cells/immunology , Peritoneal Cavity/cytology , Plant Extracts/pharmacology , Plant Leaves/chemistry , Pleurisy/chemically induced , Pleurisy/immunology , Rats, Wistar
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