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1.
Heliyon ; 9(10): e20773, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37876449

RESUMO

This study presents a novel enhanced exponential class of estimators for population mean under RSS by employing data on an auxiliary variable. The suggested estimators' mean square error (MSE) is calculated approximately at order one. The efficiency conditions that make the suggested enhanced exponential class of estimators superior to the traditional estimators are found. A simulation study using hypothetically drawn normal and exponential populations evaluates the execution of the suggested estimators. The findings demonstrate that the suggested estimators outperform their traditional equivalents. In addition, real data examples are examined to show how the proposed estimators can be implemented in various real life problems.

2.
Amino Acids ; 55(11): 1655-1664, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37782378

RESUMO

Vitamin C plays a very important role in the repair of connective tissue, especially for sports whose training causes the most damage to this tissue. Therefore, many people believe that L-ascorbic acid (C6H8O6: vitamin C) reduces the recovery time between sports exercises. The most abundant form of structural protein in the body is collagen. Collagen is characterized by a high concentration of the three amino acids glycine (Gly), proline (Pro), and hydroxyproline (Hyp), which creates its characteristic triple helix structure. Therefore, in this study, the effect of vitamin C presence on the sequence, interaction, and orientation of amino acids for collagen formation is investigated using computational simulation. This study aimed to investigate the mechanism of action of vitamin C in terms of thermodynamics and structure of the reaction. The calculations are performed using density function theory (DFT) by the base set of B3LYP/6-311++G (p,d). The results show that the presence of vitamin C is effective in the formation of collagen protein for this interaction and the mechanism of amino acid sequence (Gly-Hyp-Pro) is better in the formation of collagen protein in the presence of vitamin C. The presence of Vit-C in the formation and direction of hydroxyproline (Hyp) causes its separation from the prolyl 5-hydroxylase enzyme. In the absence of vitamin C, the reaction stops at this stage and proline cannot be converted into hydroxyproline. The computational data shows vitamin C prevents unwanted interactions and directs amino acid reactions to repair connective tissue (collagen). Therefore, vitamin C acts as a cofactor in the Prolyl 5-Hydroxylase enzyme and causes it to convert proline to hydroxyl.


Assuntos
Aminoácidos , Prolina , Humanos , Hidroxiprolina/química , Estrutura Secundária de Proteína , Prolina/química , Colágeno/química , Glicina , Ácido Ascórbico , Oxigenases de Função Mista
3.
Results Phys ; 31: 104966, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34840939

RESUMO

Motivated by the connotation of survival Rényi entropy and its related dynamic version, we introduce them in terms of their lower bounds and mean residual life function. Moreover, we illustrate the relation between survival Rényi entropy and some of measures of information. Furthermore, the hazard rate order implies ordering of dynamic survival Rényi entropy. Our models are considered a more comprehensive version of generalized order statistics and give some properties and characterization results. Finally, a non-parametric estimation of survival Rényi entropy is included based on real COVID-19 data and simulated data.

4.
Int J Pediatr Otorhinolaryngol ; 75(9): 1117-22, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21719119

RESUMO

UNLABELLED: Specific language impairment is a relatively common developmental condition in which a child fails to develop language at the typical rate despite normal general intellectual abilities, adequate exposure to language, and in the absence of hearing impairments, or neurological or psychiatric disorders. There is much controversy about the extent to which the auditory processing deficits are important in the genesis specific language impairment. The objective of this paper is to assess the higher cortical functions in children with specific language impairment, through assessing neurophysiological changes in order to correlate the results with the clinical picture of the patients to choose the proper rehabilitation training program. SUBJECTS AND METHOD: This study was carried out on 40 children diagnosed to have specific language impairment and 20 normal children as a control group. All children were subjected to the assessment protocol applied in Kasr El-Aini hospital. They were also subjected to a language test (receptive, expressive and total language items), the audio-vocal items of Illinois test of psycholinguistic (auditory reception, auditory association, verbal expression, grammatical closure, auditory sequential memory and sound blending) as well as audiological assessment that included peripheral audiological and P300 amplitude and latency assessment. The results revealed a highly significant difference in P300 amplitude and latency between specific language impairment group and control group. There is also strong correlations between P300 latency and the grammatical closure, auditory sequential memory and sound blending, while significant correlation between the P300 amplitude and auditory association and verbal expression. CONCLUSION: Children with specific language impairment, in spite of the normal peripheral hearing, have evidence of cognitive and central auditory processing defects as evidenced by P300 auditory event related potential in the form of prolonged latency which indicate a slow rate of processing and defective memory as evidenced by small amplitude. These findings affect cognitive and language development in specific language impairment children and should be considered during planning the intervention program.


Assuntos
Córtex Auditivo/fisiopatologia , Potenciais Evocados P300 , Transtornos da Linguagem/diagnóstico , Psicolinguística/métodos , Distribuição por Idade , Vias Auditivas , Percepção Auditiva/fisiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Egito/epidemiologia , Feminino , Humanos , Incidência , Desenvolvimento da Linguagem , Transtornos da Linguagem/epidemiologia , Testes de Linguagem , Masculino , Valores de Referência , Fatores de Risco , Índice de Gravidade de Doença , Distribuição por Sexo
5.
J Laryngol Otol ; 119(12): 950-4, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16354356

RESUMO

OBJECTIVE: To investigate the relationship between the extent of sinus disease in chronic sinusitis as detected radiologically by computed tomography (CT) scan and the population of cilia (ciliary area) both before and after functional endoscopic sinus surgery (FESS). In a simple way this is a trial to statistically prove that the CT scan could be a valid indicator and a mirror of the histological status of the sinus mucosa. DESIGN: Twenty adult patients were enrolled in this study. Radiological extension of the sinus disease was quantitated using the classification proposed by Kennedy in 1992 and the ciliary population was studied using scanning electron microscopy and image analysis softwares. RESULTS AND CONCLUSION: The more advanced the sinusitis, as evidenced by CT scans, the more the expected reduction in the ciliary area (CA) and in the ciliary count. But after FESS the degree of ciliary regeneration does not depend statistically on the radiological condition of the sinuses and the degree of opacity prior to intervention, i.e. a statistically valid inverse relationship exists between the radiological stage of sinusitis and the ciliary population pre-operatively but the same relation does not extend to the ciliary population post-operatively.


Assuntos
Seios Paranasais/diagnóstico por imagem , Sinusite/diagnóstico por imagem , Adolescente , Adulto , Doença Crônica , Cílios/diagnóstico por imagem , Endoscopia/métodos , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Seios Paranasais/cirurgia , Seios Paranasais/ultraestrutura , Valor Preditivo dos Testes , Sinusite/cirurgia , Tomografia Computadorizada por Raios X/normas
6.
J Laryngol Otol ; 117(4): 273-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12816216

RESUMO

This was a study of the effect of functional endoscopic sinus surgery (FESS) on the ciliary regeneration of maxillary sinus mucosa in patients with chronic maxillary sinusitis, using objective quantitative methods. Twenty specimens from the mucosa of both the superolateral wall and the ostium of the maxillary sinus were sampled during FESS and then six to 12 months later. They were light examined first by light microscopy and then by scanning electron microscopy in combination with image analysis software in order to study the cilia under higher magnification and to calculate proportion of the field that was ciliated. Samples were taken and studied at Cairo University hospital. This study showed that the maxillary sinus mucosa in chronic sinusitis is capable of regeneration and could return towards normal with the improvement of ventilation and drainage of the maxillary sinus following FESS. There were no significant changes in the degree of glandular hyperplasia, goblet cells or pathological glands after surgery.


Assuntos
Seio Maxilar/ultraestrutura , Sinusite Maxilar/patologia , Mucosa Nasal/ultraestrutura , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Adolescente , Adulto , Doença Crônica , Cílios/ultraestrutura , Endoscopia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Seio Maxilar/cirurgia , Sinusite Maxilar/cirurgia , Microscopia Eletrônica de Varredura/métodos , Pessoa de Meia-Idade , Mucosa Nasal/cirurgia
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