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In this paper, experimental tensile tests for pre-cracked high Carbon steel ‘C90’ specimens were performed for quasi-static and dynamic loading. High loading velocity affects the crack patterns by preventing deflection. On the other hand, an efficient numerical tool based on the phase field model was developed and validated to predict brittle fracture trajectories. A staggered numerical scheme was adopted to solve the displacement and damage fields separately. Implementation efficiency in initiating and propagating cracks, even from an undamaged microstructure, was proved. The effect of the critical fracture energy density Gc on the crack path was tested; with smaller Gc, the crack patterns become more complex. In addition, the impact of loading velocities was examined, and earlier and faster crack formation and greater crack branching is observed with higher impact velocity. In this study, bidimensional plane stress cases were treated. The phase field model with hybrid formulation was able to predict crack pattern and especially crack arrest and branching found in the literature. The developed model accurately determined the transition zone of the crack path topology that has been observed experimentally.

Background: Hydatidosis is a major health problem is many countries. It is a parasitic disease that can affect adults as well as children. Hydatid cyst often involves the lungs in children. Given the anatomical and physiological differences between children and adults, generalization from adult studies is inappropriate. Methods: To determine particularities of lung echinococcosis in children, we conducted a retrospective study of all cases treated for hydatid cyst of the lung at our department. Results: One hundred fifteen children (average age, 7 years 6 months; range, 3–15 years) were managed for pulmonary hydatid cyst, which corresponds to 66% of all hydatid localizations. Male predominance was noted (sex ratio=1.94). Cough (60.9%) and chest pain (59.1%) were the most common clinical features. Fever and fatigue were noted in 57 (49.5%) and 34 (29.5%) cases, respectively. Giant cysts were seen in 11 patients (10%). The cysts were mostly diagnosed when they are intact (68.7%). Mixed hepatic and pulmonary cysts were noted in 27 cases (4.25%). Conservative muscle-sparing surgery was performed in all cases. Complications were noted in 20% of the cases. Conclusion: As hydatidosis has a different pattern in children, optimal management requires a better knowledge of its particularities in this age group.

Spigelian hernia is an uncommon surgical condition in children and accounts for only 1% of all abdominal hernias. Its traumatic origin has been described sporadically in the literature.We report a case of a 9-year-old boy, brought to the emergency department 2 hours after abdominal trauma caused by a bicycle's handlebar grip at the lower abdomen, complaining of abdominal pain. Apart from edema, bruising and tenderness of the right of lower abdomen, physical examination showed a 1.5 * 2 cm reducible swelling lateral to the rectus muscle and a 1-cm facial defect of the anterior abdominal wall at the same site. Ultrasonography concluded to diastasis between the rectus abdominis muscle and the broad abdominal muscles with evidence of a hernia sac. The diagnosis of traumatic Spigelian hernia was retained and the patient was operated on. He had primary repair of the defect in layers using interrupted sutures. He was discharged in the same day and the aftermath of surgery was uneventful.In conclusion, traumatic Spigelian hernias are rare entities in children which diagnosis should be considered following blunt abdominal trauma. We recommend careful abdominal examination after trauma to highlight swelling and/or aponeurotic defect.

Prokaryotes play an important role in biogeochemical cycling in marine ecosystems, but little is known about their diversity and composition, and how they may contribute to the ecological functioning of coastal areas in the South Mediterranean Sea. This study investigated bacterial and archaeal community diversity in seawater samples along the Tunisian coast subject to important physicochemical disturbances. The 16S amplicon sequencing survey revealed higher prokaryotic diversity in the northern Tunisian bays than in southeastern waters (Gulf of Gabès). The major taxonomic groups identified in all samples were Alphaproteobacteria (40.9%), Gammaproteobacteria (18.7%), Marine Group II Euryarchaeota (11.3%), and Cyanobacteria (10.9%). Among them, the relative abundance of Alteromonadales, Prochlorococcus, and some clades of Pelagibacterales (SAR11) significantly differed between the northern and the southern bays, whereas no difference was observed across coastal waters in the archaeal Candidatus Poseidoniales (MGII), Synechococcus, and Pelagibacteraceae (SAR11 clade Ia), for which no relationship was observed with the environmental variables. Both Pseudoalteromonas and Alteromonas levels increased with the increasing salinity, density and nutrients (NH4+ and/or PO43–) gradients detected toward the southern waters, while the SAR11 clades Ib and IV and Prochlorococcus, decreased in the shallow, salty and nutrient-rich coastal waters of the Gulf of Gabès. Rhodobacteraceae was positively correlated with Synechococcus and chlorophyll levels, suggesting a relationship with phytoplankton biomass. The present study provides the first insights into planktonic prokaryotic community composition in the South Mediterranean Sea through the analysis of Tunisian seawaters, which may support further investigations on the role of bacterioplankton in the biogeochemistry of these ecosystems.

We report a unique case of intestinal duplication detected on posterior reversible encephalopathy syndrome (PRES) in a 13-year-old girl. She was admitted to the pediatric Emergency Department because of generalized seizures. Radiological assessment revealed a large, well-defined, thick-walled cystic lesion in the mid abdomen, suggestive of duplication cyst associated to a PRES. Exploration confirmed the diagnosis of ileal duplication cyst, and the mass was resected. The postoperative course was uneventful. Both hypertension and neurological dysfunction resolved after the mass resection. A followup brain magnetic resonance imaging was performed 9 months later and showed complete resolution of the cerebellar changes. Although extrinsic compression of the retroperitoneal structures has not been reported in the literature as a complication of duplication cyst, we strongly believe that this is the most logical and plausible hypothesis that would explain the pathogenesis of PRES in our patient.

In the case of casting processes with permanent molds, there is still a relatively pronounced lack of knowledge regarding the locally prevailing heat transfer between casts and mold. This in turn results in an insufficient knowledge of the microstructure and the associated material properties in the areas of the casting component close to the surface. Therefore, this work deals with the design and evaluation of a test tool with an integrated sensor system for temperature measurements, which was applied to obtain a time-dependent heat transfer coefficient (HTC) during casting solidification. For this purpose, the setup, design and computational approach are described first. Special attention is paid to the qualification of the multi-depth sensor and the calculation method. For the calculations, an inverse estimation method (nonlinear sequential function) was used to obtain the HTC profiles from the collected data. The developed sensor technology was used in a test mold to verify the usability of the sensor technology and the plausibility of the obtained calculation results under real casting conditions and associated temperature loads. Both the experimental temperature profiles and the HTC profiles showed that, in the evaluated casting series, the peak values determined were close to each other and reached values between 6000 W/(m2·K) and 8000 W/(m2·K) during solidification.

Background:Dental caries is associated with oral pathogenes and Streptococcus mutans (S. mutans)is one of the primary cariogenic organisms. The aim of this clinical study was to evaluate the effect of sugar free chewing gum containing casein phosphopeptide-amorphous calcium phosphate(CPP-ACP) and Xylitol on salivary Streptococcus mutan. Materials and Methods: 60 dental students, who volunteered after signing an informed consent, were randomly allocated to receive one of the following interventions: (A) Chewing gum containing CPP-ACP, (B) Chewing gum containing Xylitol. Subjects within the experimental groups chewed gum for 20 minutes, three times a day after meals for 3 weeks. Pre- and post-intervention unstimulated saliva samples were quantified for Streptococcus mutans count. Results: A statistically significant reduction (pS. mutans was displayed in both groups A and B after the intervention. When results compared with baseline, and group A shows more statistically significant reduction of salivary S. mutans than group B.Conclusion: In conclusion, daily chewing gum containing CPP-ACP and xylitol reduce the level of salivary S. mutans in a significant way, but chewing gum containing CPP-ACP can reduce the level of salivary S. mutans in a significant way than Xylitol chewing gum.

Echinococcosis is a multisystem disease and has propensity to involve any organ, an unusual anatomical site, and can mimic any disease process. The hydatid cyst of the mesenteries known to occur secondary to hepatic involvement but occasional cases of his primitive form has also been reported. We report here one such case of primitive mesenteric hydatid cyst herniated through inguinal canal in a 5-yr-old boy, admitted to our Pediatric Surgery Department of Children’s Hospital in Tunis, Tunisia in 2015.

Proteins containing nucleotide binding sites (NBS) encoded by plant resistance genes play an important role in the response of plants to a wide array of pathogens. In this paper, an in silico search was conducted in order to identify and characterize members of NBS-encoding gene family in the tribe of Triticeae. A final dataset of 199 sequences was obtained by four search methods. Motif analysis confirmed the general structural organization of the NBS domain in cereals, characterized by the presence of the six commonly conserved motifs: P-loop, RNBS-A, Kinase-2, Kinase-3a, RNBS-C and GLPL. We revealed the existence of 11 distinct distribution patterns of these motifs along the NBS domain. Four additional conserved motifs were shown to be significantly present in all 199 sequences. Phylogenetic analyses, based on genetic distance and parsimony, revealed a significant overlap between Triticeae sequences and Coiled coil-Nucleotide binding site-Leucine rich repeat (CNL)-type functional genes from monocotyledons. Furthermore, several Triticeae sequences belonged to clades containing functional homologs from non Triticeae species, which has allowed for these sequences to be functionally assigned. The findings reported, in this study, will provide a strong groundwork for the isolation of candidate R-genes in Triticeae crops and the understanding of their evolution.

Background: Lipoblastoma is a rare benign mesenchymal tumour of embryonal fat that occurs almost exclusively in infants and children. This determined the epidemiological, clinical and therapeutic aspect of this disease. Materials and Methods: A total of 10 cases of pathologically proven lipoblastoma from 2003 to 2012 were reviewed. Results: There were six boys and four girls ranging in age from 7 months to 9 years. A soft-tissue mass was the main complain in nine patients. The various locations of the mass were mediastinal, thigh, buttock, inguino-scrotal, the greater omentum and the Latissimus dorsi. Lesions measured 5-15 cm. complete excision was done. The median time of follow-up was 42 months (ranges between 18 and 84 months). There were no recurrences. Conclusion: It is important to consider lipoblastoma in the diagnosis of a rapidly enlarging fatty mass in children. Complete resection is the only definitive treatment and should not be delayed when impingement on surrounding structures is imminent. There is a tendency for these lesions to recur despite presumed complete excision. Therefore, follow-up for a minimum of 5 years is recommended.

Background: Liver hydatid cyst affects approximately 95% of the world's echinococcosis cases. Despite advances in treatment, the recurrence rate remains high and is influenced by several factors that are yet to be determined. The objective of this study was to identify the predictive factors of liver hydatid cyst recurrence following surgery in children and to establish a treatment regimen aimed at preventing this postoperative morbidity., Methods: A bi-centric retrospective descriptive and analytic study was conducted involving 122 children who underwent surgery for liver hydatid cysts between January 1st, 2009, and December 31st, 2017. All factors that could potentially contribute to recurrence were thoroughly investigated. The data was processed using SPSS.v21, and a significant level of p-value 0.05 was applied., Results: Out of the 122 children, 20 patients experienced cyst recurrence (16.39%). Among them, there were nine girls and eleven boys. The median time of recurrence was 16.5 months. Abdominal ultrasonography demonstrated efficacy in detecting recurrence. Several factors were identified as predictors of postoperative recurrence, including intimate contact of the hydatid cyst with the large vessels (p = 0.031), intraperitoneal effusion (p = 0.042), bile duct dilation (p = 0.032), and postoperative spontaneous discontinuation of medical treatment (p = 0.010). Among these factors, two independent risk factors for recurrence were identified: intimate contact of the hydatid cyst with the large vessels (p = 0.011) and the presence of an intraperitoneal effusion (p = 0.018)., Conclusion: Our study has identified several predictors of postoperative recurrence, including two previously undocumented risk factors in the literature. Awareness of these risk factors can assist surgeons in implementing preventive measures to avoid the recurrence of hydatid cysts., Level of Evidence: Prognosis study Level II., (Copyright © 2023 Elsevier Inc. All rights reserved.)

We report the a case of a four-year old male child with a glans amputation secondary to circumcision, in whom a spongiocavernosal shunt, also called "winter shunt" was practiced. The aim of this report is to review the role of this technique in postoperative viability., Competing Interests: Declaration of Competing Interest No potential conflict of interest relevant to this article was reported., (Copyright © 2020 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

In plant cells, the manganese superoxide dismutase (Mn-SOD) plays an elusive role in the response to oxidative stress. In this study, we describe the isolation and functional characterization of a novel Mn-SOD from durum wheat (Triticum turgidum L. subsp. Durum), named TdMnSOD. Molecular phylogeny analysis showed that the durum TdMnSOD exhibited high amino acids sequence identity with other Mn-SOD plants. The three-dimensional structure showed that TdMnSOD forms a homotetramer and each subunit is composed of a predominantly α-helical N-terminal domain and a mixed α/β C-terminal domain. TdMnSOD gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdMnSOD enhances tolerance of the transformed yeast cells to salt, osmotic, cold and H2O2-induced oxidative stresses. Moreover, the analysis of TdMnSOD transgenic Arabidopsis plants subjected to different environmental stresses revealed low H2O2 and high proline levels as compared to the wild-type plants. Compared with the non-transformed plants, an increase in the total SOD and two other antioxidant enzyme activities including catalase (CAT) and peroxidases (POD) was observed in the three transgenic lines subjected to abiotic stress. Taken together, these data provide evidence for the involvement of durum wheat TdMnSOD in tolerance to multiple abiotic stresses in crop plants., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

Ecthyma gangrenosum is a characteristic lesion of Pseudomonas aeruginosa sepsis in immunocompromised patients. Only eight cases of ecthyma gangrenosum caused by Escherichia coli have been reported. We report a case of ecthyma gangrenosum due to E. coli without bacteremia in a previously healthy girl., (© 2015 Wiley Periodicals, Inc.)