A Delayed Black and Scholes Formula I

In this article we develop an explicit formula for pricing European options when the underlying stock price follows a non-linear stochastic differential delay equation (sdde). We believe that the proposed model is sufficiently flexible to fit real market data, and is yet simple enough to allow for a closed-form representation of the option price. Furthermore, the model maintains the no-arbitrage property and the completeness of the market. The derivation of the option-pricing formula is based on an equivalent martingale measure

Pediatric recurrent respiratory tract infections: when and how to explore the immune system? (About 53 cases)

Recurrent respiratory tract infections are one of the most frequent reasons for pediatric visits and hospitalization. Causes of this pathology are multiple ranging from congenital to acquired and local to general. Immune deficiencies are considered as underlying conditions predisposing to this pathology. Our work is about to determine when and how to explore the immune system when facing recurrent respiratory infections. This was based on the records of 53 children hospitalized at the pediatrics unit of Hassan II University Hospital, Fez Morocco. Thirty boys and 23 girls with age ranging from 5 months to 12 years with an average age of 2 years were involved in this study. Bronchial foreign body was the main etiology in children of 3 to 6 year old. Gastro-esophageal reflux, which in some cases is a consequence of chronic cough, as well as asthma were most frequent in infants (17 and 15% respectively). Immune deficiency was described in 7.5% of patients and the only death we deplored in our series belongs to this group. Recurrent respiratory tract infections have multiple causes. In our series they are dominated by foreign body inhalation and gastroesophageal reflux, which in some cases is a consequence of a chronic cough. Immune deficiency is not frequent but could influence the prognosis. Therefore immune explorations should be well codified.Pan African Medical Journal 2016; 2

Moroccan Leishmania infantum: Genetic Diversity and Population Structure as Revealed by Multi-Locus Microsatellite Typing

Leishmania infantum causes Visceral and cutaneous leishmaniasis in northern Morocco. It predominantly affects children under 5 years with incidence of 150 cases/year. Genetic variability and population structure have been investigated for 33 strains isolated from infected dogs and humans in Morocco. A multilocus microsatellite typing (MLMT) approach was used in which a MLMtype based on size variation in 14 independent microsatellite markers was compiled for each strain. MLMT profiles of 10 Tunisian, 10 Algerian and 21 European strains which belonged to zymodeme MON-1 and non-MON-1 according to multilocus enzyme electrophoresis (MLEE) were included for comparison. A Bayesian model-based approach and phylogenetic analysis inferred two L.infantum sub-populations; Sub-population A consists of 13 Moroccan strains grouped with all European strains of MON-1 type; and subpopulation B consists of 15 Moroccan strains grouped with the Tunisian and Algerian MON-1 strains. Theses subpopulations were significantly different from each other and from the Tunisian, Algerian and European non MON-1 strains which constructed one separate population. The presence of these two sub-populations co-existing in Moroccan endemics suggests multiple introduction of L. infantum from/to Morocco; (1) Introduction from/to the neighboring North African countries, (2) Introduction from/to the Europe. These scenarios are supported by the presence of sub-population B and sub-population A respectively. Gene flow was noticed between sub-populations A and B. Five strains showed mixed A/B genotypes indicating possible recombination between the two populations. MLMT has proven to be a powerful tool for eco-epidemiological and population genetic investigations of Leishmania.The fieldwork and data collection was granted by Pastur Institute in Morocco for Dr. Meryem Lemrani. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Effect of gold-nanoparticle size on microfiber saturable absorber for mode-locked erbium-doped fiber lasers

Effect of gold-nanoparticle size on microfiber saturable absorber for mode-locked erbium-doped fiber lasers The optical performance of passively mode-locked erbium-doped fiber laser incorporating gold-nanoparticles (Au-NPs) of different sizes as saturable absorbers (SAs) was compared. A composite of Au-NPs with polydimethylsiloxane was spin coated on the surface of a microfiber waveguide. The fabricated Au-NP-based SA was deployed in a ring cavity erbium-doped fiber laser and its lasing performance was evaluated by comparing SA characteristics as well as pulse qualities among the different Au-NP sizes. The optimum pulse performance was realized when the SA was fabricated with 20 and 40 nm Au-NP size. For the former, time-bandwidth product of 0.34 was demonstrated which was the closest to its bandwidth-limited pulse. As for the latter, the fabricated SA exhibited 4.0% modulation depth and an average pulse duration of 886.7 fs. The research work has demonstrated the functionality of Au-NPs as a saturable absorption material for ultrashort pulses generation. In addition, the influence of nanomaterial size towards the characteristics of saturable absorbers, ergo the quality of laser pulse, was verified. This finding is also valuable in customizing ultrashort pulse output that can effectively suit system performance need

Clinicopathological and prognostic significance of EGFR, VEGF, and HER2 expression in cholangiocarcinoma

Epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), and human epidermal growth factor receptor 2 (HER2) have been considered as potential therapeutic targets in cholangiocarcinoma, but no studies have yet clarified the clinicopathological or prognostic significance of these molecules. Immunohistochemical expression of these molecules was assessed retrospectively in 236 cases of cholangiocarcinoma, as well as associations between the expression of these molecules and clinicopathological factors or clinical outcome. The proportions of positive cases for EGFR, VEGF, and HER2 overexpression were 27.4, 53.8, and 0.9% in intrahepatic cholangiocarcinoma (IHCC), and 19.2, 59.2, and 8.5% in extrahepatic cholangiocarcinoma (EHCC), respectively. Clinicopathologically, EGFR overexpression was associated with macroscopic type (P=0.0120), lymph node metastasis (P=0.0006), tumour stage (P=0.0424), lymphatic vessel invasion (P=0.0371), and perineural invasion (P=0.0459) in EHCC, and VEGF overexpression with intrahepatic metastasis (P=0.0224) in IHCC. Multivariate analysis showed that EGFR expression was a significant prognostic factor (hazard ratio (HR), 2.67; 95% confidence interval (CI), 1.52–4.69; P=0.0006) and also a risk factor for tumour recurrence (HR, 1.89; 95% CI, 1.05–3.39, P=0.0335) in IHCC. These results suggest that EGFR expression is associated with tumour progression and VEGF expression may be involved in haematogenic metastasis in cholangiocarcinoma

The scent of roses, a bouquet of fragrance diversity

International audienceAbstract Roses have been domesticated since antiquity for their therapeutic, cosmetic, and ornamental properties. Their floral fragrance has great economic value, which has influenced the production of rose varieties. The production of rose water and essential oil is one of the most lucrative activities, supplying bioactive molecules to the cosmetic, pharmaceutical, and therapeutic industries. In recent years, major advances in molecular genetics, genomic, and biochemical tools have paved the way for the identification of molecules that make up the specific fragrance of various rose cultivars. The aim of this review is to highlight current knowledge on metabolite profiles, and more specifically on fragrance compounds, as well as the specificities and differences between rose species and cultivars belonging to different rose sections and how they contribute to modern roses fragrance

Children’s poisoning profile during the Covid-19 pandemic – Experience of Hassan II University Hospital in Fez, MOROCCO

Introduction. —The Covid-19 pandemic and the containment situation, has generated enormous risks for children. Indeed, with the closure of schools, children, forced to stay at home, found themselves in permanent contact with dangerous products (drugs, disinfectants, plants) exposing them to accidental poisoning. Objective. —To describe the epidemiological, clinical and evolutionary aspects of the cases of pediatric intoxications in the UHC during the period of Covid-19, in order to assess the repercussions of this pandemic on the profile of these intoxications, in terms of number and incriminated products. Material and method. — This is a retrospective descriptive comparative study of intoxication cases admitted to the pediatric emergency department of the University Hospital of Fez spread over 2 years; from March 1, 2019 to February 2021; comparing intoxications admitted during the period of Covid-19 with the previous year. Results. — The emergency department recorded 132 cases of intoxication during the Covid-19 period (compared to 104 cases in 2019). Fez was always the most concerned city (66.21% against 69.02% in 2019). The cases emanated from the urban environment in (58.78%). The accidental circumstance was the most frequent, with an increase from 77.88% in 2019 to 82.02%. The rate of cases of envenomation that consulted was almost similar; children are more exposed to scorpion stings (73.52%) than snake bites. The analysis of incriminated products was marked by the increase of Caustics (20.38% in 2019 to 24.24% in 2020), and the decrease of pesticides (19.41% in 2019 to 13.63%). The symptomatology was dominated by neurological signs in 25.75% of cases, followed by respiratory disorders (18.18%). The evolution was favorable in 95.46%, and death occurred in 4.54% of cases compared to 3.84% in2019. The Covid-19 pandemic has changed the use of antidotes

Estimated population structure for 33 Moroccan <i>L. infantum</i> strains as inferred by STRUCTURE software on the basis of data for 14 microsatellite markers.

<p>Each of the strains is represented by a single vertical line divided into K colors, where K is the number of populations assumed. Each color represents one population, and the length of the colors segment shows the strain’s estimated proportion of membership in that population.(A) the two main populations derived from the whole dataset which divided strains into MON-1 and non-MON-1 populations. (B) Sub-population analysis of <b>Population 1</b> (MON-1 group) shows two sub-populations. K represents the true number of populations and sub-populations.</p

Map of Morocco with all areas endemic for VL (shadowed areas).

<p>Map of Morocco with all areas endemic for VL (shadowed areas).</p