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1.
Heliyon ; 10(3): e24914, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38317929

RESUMO

Understanding the impact of various parameters on the kinetics of dissolved selenium (Se) removal in bioreactors can be a challenging task, primarily due to the mass transfer limitations inherent in bioreactors employing attached growth configurations. This study successfully established a proof-of-concept for the efficient removal of Se from aqueous solutions using a chemostat bioreactor that relies solely on suspended growth. The research investigated the effect of selenate-Se feed concentrations under two distinct Se concentration conditions. One experiment was conducted at a considerably elevated concentration of 25 mg/L to impose stress on the system and evaluate its response. Another experiment replicated an environmentally relevant concentration of 1 mg/L, mirroring the typical Se concentrations in mine water. The bioreactor, featuring a working volume of 0.35 L, was operated as an anaerobic, fully mixed chemostat with hydraulic retention times (HRTs) ranging from 5 to 0.25 days. The outcomes revealed the chemostat's capacity to remove up to 25 mg/L of dissolved Se from water for all HRTs exceeding 1 day, under otherwise optimal conditions encompassing temperature, pH, and salinity. The research's significance lies in the development of a versatile tool designed to examine Se removal kinetics within a system devoid of mass transfer limitations. Furthermore, this study verified the ability of the bacterial consortium, obtained from a mine-influenced environment and enriched in the laboratory, to grow and sustain Se removal activities within a chemostat operating with HRTs as short as 1 day.

2.
Comput Biol Med ; 109: 242-253, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31096088

RESUMO

Accurate segmentation of the sperms in microscopic semen smear images is a prerequisite step in automatic sperm morphology analysis. It is a challenging task due to the non-uniform distribution of light in semen smear images, low contrast between sperm's tail and its surrounding region, the existence of various artifacts, high concentration of sperms and wide spectrum of the shapes of the sperm's parts. This paper proposes an automatic framework based on concatenated learning approaches to segment the external and internal parts of the sperms. The external parts of the sperms are segmented using two convolutional neural network (CNN) models which produce the probability maps of the head and the axial filament regions. To obtain acrosome and nucleus segments, the K-means clustering approach is applied to the head segments. A Support Vector Machine (SVM) classifier is used to classify each pixel of the axial filament segments to extract tail and mid-piece regions from obtained segments. The proposed method is validated on the images of the Gold-standard dataset. It achieves 0.90, 0.77, 0.77, 0.78, 0.75 and 0.64 of the average of dice similarity coefficient for the head, axial filament, acrosome, nucleus, tail, and mid-piece segments, respectively. Experimental results demonstrate that the proposed method outperforms state-of-the-art algorithms for the head and its internal parts segmentation. It also segments the axial filament region and its internal parts with desirable accuracy. Different from previous works, the proposed method is able to segment all parts of the sperms which enables automatic quantitative analysis of the sperm morphology.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Análise do Sêmen , Espermatozoides/citologia , Máquina de Vetores de Suporte , Humanos , Masculino , Microscopia
3.
Iran J Pediatr ; 22(1): 23-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23056855

RESUMO

OBJECTIVE: Familial Mediterranan Fever is an hereditary autoinflammatory disease that presents with recurrent febrile attacks and poly serositis. Colchicine is the only known treatment in this diease. However, nearly 5-10% of patients are resistant to colchicines. There are many different modalities in colchicine resistant patients, biologic and immunosupressive drugs being the known ones. We studied the efficacy of Dapsone as an anti inflammatory drug in children with FMF who did not tolerate colchicine well. METHODS: This is a case series study in 10 patients who had FMF on the base of Tel-Hashomer criteria and did not tolerate colchicine or did not respond to it well. Patients took 2mg/kg dapsone in single dose, during 6 months. FINDINGS: In four patients episodic attacks returned after 27 days, so the drug was discontinued. One patient refused to continue the study; in five patients dapsone was taken in average for 8 months and 6 days, at least for 6 months. These five patients had no episodes of attack during the following observation. CONCLUSION: Dapsone could control episodic attacks of FMF in 50% of cases. It might be considered as an alternative therapy in FMF cases not responding to colchicine.

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