Monte-Carlo methods for the pricing of American options: a semilinear BSDE point of view

We extend the viscosity solution characterization proved in [5] for call/put American option prices to the case of a general payoff function in a multi-dimensional setting: the price satisfies a semilinear re-action/diffusion type equation. Based on this, we propose two new numerical schemes inspired by the branching processes based algorithm of [8]. Our numerical experiments show that approximating the discontinu-ous driver of the associated reaction/diffusion PDE by local polynomials is not efficient, while a simple randomization procedure provides very good results

Triceps skin fold thickness as a measure of body fat in Nigerian adolescents

Background: Skin fold thickness (SFT) at selected areas offers a simple method of subcutaneous fat assessment and provides a good estimate of obesity and body fat distribution. The triceps SFT has been shown to be one of the best and most popular sites for SFT measurement in children.Objective: To assess the body fat of school adolescents and to comparethe performance of triceps SFT with Bioelectrical impedance method in the detection of overweight (OW) and obesity (OB) among the subjectsMethods: The study was cross sectional; involving secondary schoolstudents within Sokoto metropolis. Subjects were selected by a multistagerandom sampling method. Harpenden skin fold caliper (ASSIST Creative Resources Ltd, LL13 9UG, UK) and Tanita Body fat scale (model UM-030, Tanita, UK Ltd; 2004) were used respectively to measure the triceps SFTand body fat content (%) according to the manufacturer’s instructions. Results: The mean triceps SFT values were 8.9mm (±4.7) for malesand 12.9mm (±4.6) for the females (p<0.001). Mean % BF values were8.2 ± 4.1% for the males, and 20.0 ± 6.8% for the females (p<0.001).The triceps SFT gave a prevalence of overweight of 2.5%, while that of obesity was 0.8%. With the BIA method, 2.5% of the subjects wereclassified as overweight and 1.7% as obese.Conclusion: Triceps SFT remain a fair surrogate for the assessment ofadiposity, the component of overweight that leads to pathology.Key words: Skin fold thickness, bioelectrical impedance analysis, body fat, obesity, adolescent

Ru-Catalyzed, cis-Selective Living Ring-Opening Metathesis Polymerization of Various Monomers, Including a Dendronized Macromonomer, and Implications to Enhanced Shear Stability

An unsaturated polymer’s cis/trans-olefin content has a significant influence on its properties. For polymers obtained by ring-opening metathesis polymerization (ROMP), the cis/trans-olefin content can be tuned by using specific catalysts. However, cis-selective ROMP has suffered from narrow monomer scope and lack of control over the polymerization (giving polymers with broad molecular weight distributions and prohibiting the synthesis of block copolymers). Herein, we report the versatile cis-selective controlled living ROMP of various endo-tricyclo[4.2.2.0^(2,5)]deca-3,9-diene and various norbornene derivatives using a fast-initiating dithiolate-chelated Ru catalyst. Polymers with cis-olefin content as high as 99% could be obtained with high molecular weight (up to M_n of 105.1 kDa) and narrow dispersity (<1.4). The living nature of the polymerization was also exploited to prepare block copolymers with high cis-olefin content for the first time. Furthermore, owing to the successful control over the stereochemistry and narrow dispersity, we could compare cis- and trans-rich polynorbornene and found the former to have enhanced resistance to shear degradation

Monte-Carlo methods for the pricing of American options: a semilinear BSDE point of view

We extend the viscosity solution characterization proved in [5] for call/put American option prices to the case of a general payoff function in a multi-dimensional setting: the price satisfies a semilinear re-action/diffusion type equation. Based on this, we propose two new numerical schemes inspired by the branching processes based algorithm of [8]. Our numerical experiments show that approximating the discontinu-ous driver of the associated reaction/diffusion PDE by local polynomials is not efficient, while a simple randomization procedure provides very good results

Barriers and facilitators to human immunodeficiency virus sero-status disclosure in a tertiary health facility in Kano, Nigeria

Disclosure of Human Immunodeficiency Virus (HIV) sero-status to sexual partners, family and friends is essential in preventing HIV transmission. An array of benefits has been associated with disclosure; such as early referral to care and treatment, reduced stigma and increased social support. Objectives: We determined the prevalence, barriers and facilitators to HIV sero-status disclosure among clients attending the Antiretroviral (ARV) clinic in AminuKano-Teaching Hospital, Kano. Method: A descriptive cross-sectional study was conducted among 231 HIV positive patients attending ARV clinic at AKTH using a systematic sampling technique. Interviewer-administered semi-structured questionnaire was used to obtain respondent's socio-demographic characteristics, disclosure status, barriers and facilitators of HIV sero-status disclosure. We conducted univariate, bivariate and multivariate analysis using SPSS version 22, and a p- value ≤0.05 was considered as the level of significance. Results: The mean age of the respondents was 35 ± 8.64 years with a male to female sex distribution of 53% to 47 % respectively. Majority were not married (74.0%) and two thirds (67%) were Muslims. This study found that 60% of the respondents had disclosed their HIV sero-status and 97% of them had done so voluntarily. The fear of divorce/neglect (p&lt;0.01, aOR=0.017, 95% CI=0.02-0.15) and fear of stigma (p&lt;0.01, aOR=0.03, 95% CI= 0.00-0.03) were found as barriers to HIV sero-status disclosure. Financial difficulties (p&lt;0.01, aOR=3.03, 95% CI=1.16-5.61) and the need for improved access to necessary medical care (p=0.04, aOR=6.52, 95% CI=1.85-23.15) were found to facilitate HIV sero status disclosure. Conclusion: The study found a low HIV sero-status disclosure in Kano. Disclosure being major recommendation by World Health Organisation and the Centres for Disease Control and Prevention requires strengthening during patients counselling and education sessions

Improvement of Subjective Well-Being by Ranolazine in Patients with Chronic Angina and Known Myocardial Ischemia (IMWELL Study)

Introduction: We aimed to assess if ranolazine would improve angina symptoms among patients with documented myocardial ischemia. Methods: Eligible subjects had chronic stable angina and at least one coronary stenosis with fractional flow reserve (FFR) ≤0.80 or at least one chronic total occlusion (CTO) without attempted revascularization. Subjects were randomized to oral ranolazine 500 mg twice daily for 1 week, then ranolazine 1000 mg twice daily for 15 weeks versus matching placebo. The primary end point was change in angina at 16 weeks as assessed by the Seattle Angina Questionnaire (SAQ). Results: Between September 2014 and January 2016, 25 subjects were randomized to ranolazine versus 25 to placebo. The most common reason for eligibility was CTO (72%), while the remainder had myocardial ischemia documented by low FFR. The mean FFR was 0.57 ± 0.12. Sixty-eight percent of subjects were on two or more anti-angina medications at baseline. Study medication was discontinued in 32% (eight of 25) of the ranolazine group versus 36% (nine of 25) of the placebo group. By intention-to-treat, 46 subjects had baseline and follow-up SAQ data completed. Ranolazine was not associated with an improvement in angina compared with placebo at 16 weeks. The results were similar among 33 subjects that completed study medication. The incidence of ischemia-driven hospitalization or catheterization was 12% (three of 25) of the ranolazine group versus 20% (five of 25) in the placebo group (p \u3e 0.05). Conclusions: In subjects with chronic stable angina and documented myocardial ischemia, ranolazine did not improve angina symptoms at 16 weeks

The Plasmodium knowlesi Pk41 surface protein diversity, natural selection, sub population and geographical clustering: a 6-cysteine protein family member

Introduction The zoonotic malaria parasite Plasmodium knowlesi has currently become the most dominant form of infection in humans in Malaysia and is an emerging infectious disease in most Southeast Asian countries. The P41 is a merozoite surface protein belonging to the 6-cysteine family and is a well-characterized vaccine candidate in P. vivax and P. falciparum; however, no study has been done in the orthologous gene of P. knowlesi. This study investigates the level of polymorphism, haplotypes and natural selection of pk41 genes in clinical isolates from Malaysia. Method Thirty-five full-length pk41 sequences from clinical isolates of Malaysia along with four laboratory lines (along with H-strain) were downloaded from public databases. For comparative analysis between species, orthologous P41 genes from P. falciparum, P. vivax, P. coatneyi and P. cynomolgi were also downloaded. Genetic diversity, polymorphism, haplotype and natural selection were determined using DnaSP 5.10 software. Phylogenetic relationships between Pk41 genes were determined using MEGA 5.0 software. Results Analysis of 39 full-length pk41 sequences along with the H-strain identified 36 SNPs (20 non-synonymous and 16 synonymous substitutions) resulting in 31 haplotypes. Nucleotide diversity across the full-length gene was low and was similar to its ortholog in P. vivax; pv41. Domain-wise amino acid analysis of the two s48/45 domains indicated low level of polymorphisms for both the domains, and the glutamic acid rich region had extensive size variations. In the central domain, upstream to the glutamate rich region, a unique two to six (K-E)n repeat region was identified within the clinical isolates. Overall, the pk41 genes were indicative of negative/purifying selection due to functional constraints. Domain-wise analysis of the s48/45 domains also indicated purifying selection. However, analysis of Tajima’s D across the genes identified non-synonymous SNPs in the s48/45 domain II with high positive values indicating possible epitope binding regions. All the 6-cysteine residues within the s48/45 domains were conserved within the clinical isolates indicating functional conservation of these regions. Phylogenetic analysis of full-length pk41 genes indicated geographical clustering and identified three subpopulations of P. knowlesi; one originating in the laboratory lines and two originating from Sarawak, Malaysian Borneo. Conclusion This is the first study to report on the polymorphism and natural selection of pk41 genes from clinical isolates of Malaysia. The results reveal that there is low level of polymorphism in both s48/45 domains, indicating that this antigen could be a potential vaccine target. However, genetic and molecular immunology studies involving higher number of samples from various parts of Malaysia would be necessary to validate this antigen’s candidacy as a vaccine target for P. knowlesi

Moisture computing-based internet of vehicles (IoV) architecture for smart cities

Recently, the concept of combining 'things' on the Internet to provide various services has gained tremendous momentum. Such a concept has also impacted the automotive industry, giving rise to the Internet of Vehicles (IoV). IoV enables Internet connectivity and communication between smart vehicles and other devices on the network. Shifting the computing towards the edge of the network reduces communication delays and provides various services instantly. However, both distributed (i.e., edge computing) and central computing (i.e., cloud computing) architectures suffer from several inherent issues, such as high latency, high infrastructure cost, and performance degradation. We propose a novel concept of computation, which we call moisture computing (MC) to be deployed slightly away from the edge of the network but below the cloud infrastructure. The MC-based IoV architecture can be used to assist smart vehicles in collaborating to solve traffic monitoring, road safety, and management issues. Moreover, the MC can be used to dispatch emergency and roadside assistance in case of incidents and accidents. In contrast to the cloud which covers a broader area, the MC provides smart vehicles with critical information with fewer delays. We argue that the MC can help reduce infrastructure costs efficiently since it requires a medium-scale data center with moderate resources to cover a wider area compared to small-scale data centers in edge computing and large-scale data centers in cloud computing. We performed mathematical analyses to demonstrate that the MC reduces network delays and enhances the response time in contrast to the edge and cloud infrastructure. Moreover, we present a simulation-based implementation to evaluate the computational performance of the MC. Our simulation results show that the total processing time (computation delay and communication delay) is optimized, and delays are minimized in the MC as apposed to the traditional approaches

Monte-Carlo methods for the pricing of American options: a semilinear BSDE point of view

We extend the viscosity solution characterization proved in [5] for call/put American option prices to the case of a general payoff function in a multi-dimensional setting: the price satisfies a semilinear reaction/diffusion type equation. Based on this, we propose two new numerical schemes inspired by the branching processes based algorithm of [8]. Our numerical experiments show that approximating the discontinuous driver of the associated reaction/diffusion PDE by local polynomials is not efficient, while a simple randomization procedure provides very good results