On the Complexity of Solving Zero-Dimensional Polynomial Systems via Projection

Given a zero-dimensional polynomial system consisting of n integer polynomials in n variables, we propose a certified and complete method to compute all complex solutions of the system as well as a corresponding separating linear form l with coefficients of small bit size. For computing l, we need to project the solutions into one dimension along O(n) distinct directions but no further algebraic manipulations. The solutions are then directly reconstructed from the considered projections. The first step is deterministic, whereas the second step uses randomization, thus being Las-Vegas. The theoretical analysis of our approach shows that the overall cost for the two problems considered above is dominated by the cost of carrying out the projections. We also give bounds on the bit complexity of our algorithms that are exclusively stated in terms of the number of variables, the total degree and the bitsize of the input polynomials

The behavior of the concretes and mortars reinforced by metallic fibers wastes as substitution of cement

Abstract The main objective of this work is to study the behavior of the mortar and the concretes obtained by substituting the cement by the metallic fibers wastes. Several materials were carried out by substituting the cement with different amount of fibers (0, 10, 20 and 30 wt %). Mechanical properties of the two obtained materials (mortar and concrete) as flexural and compressive strengths were studied. Physical properties as shrinkage, the swelling effect, loss in mass, slump concretes and porosity were evaluated. However, the addition of 10 wt % of the fibers in the mixtures of the mortar and the concretes is possible, due that its compressive strengths are respectively 40.9 and 27.4 MPa. The environmental risks of the incorporation of the metallic fibers rich in heavy metals (Zn and Cu) into the mixtures were evaluated by leaching tests of the obtained materials. The results indicated a very slight release of the pollutants. The obtained materials have a good performance and they are suitable for use in practice

Extraction of the Volatile Oils of Dictyopteris membranacea Batters 1902 by Focused Microwave-assisted Hydrodistillation and Supercritical Carbon Dioxide: Empirical Kinetic Modelling Approach, Apparent Solubility and Rate Constants

Supercritical carbon dioxide extraction (SCCO2) and focused microwave-assisted hydrodistillation (FMAHD) were used comparatively to isolate the volatile oils of the brown alga Dictyopteris membranacea from the crude ether extract. The volatiles fractions were analysed by GC/MS, the major compounds were: dictyopterene A, 6-butyl-1,4-cycloheptadiene, 1-undecen-3-one, 1,4-undecadien-3-one, (3-oxoundec-4-enyl) sulphur, tetradecanoic acid, hexadecanoic acid, 3-hexyl-4,5-dithiacycloheptanone, and albicanol. A kinetics study of the extraction of the volatile fractions obtained by the two processes was carried out, an external calibration allowed to quantify the content of the main metabolites. Empirical models were applied to adjust the experimental kinetics values but also to determine the values of apparent solubilities for SCCO2 and the rate constants for FMAHD. The results obtained revealed that the SCCO2 process was characterized by the coexistence of three distinct phases. For FMAHD, the extraction mechanism included two steps. This work is licensed under a Creative Commons Attribution 4.0 International License

Syringomatous carcinoma: Case report of a rare tumor entity

Syringomatous carcinoma is a rare cutaneous neoplasm, most frequently situated on the face and scalp and histologically characterised by aninfiltrative pattern of basaloid or squamous cells, a desmoplastic stromal reaction and keratin filled cysts. We report the case of a 76-year-oldwoman who presented an ulcerative interscapular lesion measuring 3x4cm. After resection, the histological examinations of the specimens haveidentified a basal cell carcinoma. However, a local recurrence was observed 18 months later; histopathological findings showed a syringomatouspattern and neoplastic epithelial cells arranged in interconnecting cords with microcystic areas. Nests, cords, and tubules of the tumour extendedinto the dermis and into the adjacent muscle. Sclerosis of stroma around the cords was present. Tumour cells were not connected to the epidermis. The immunohistochemical analysis showed positivity for anti-CK7, AE1/AE3 and negativity for anti CEA and anti CK20. These histological and immunohistochemical analyses were consistent with the diagnosis of syringomatous eccrine carcinoma. Syringomatous carcinoma is an extremely invasive tumor, locally destructive and slowly growing adnexal tumour, derived from eccrine sweat glands. It is often mistaken, both clinically and microscopically, for other benign and malignant entities. The tumour recurrence is high due to extensive perineural invasion, butregional or distant metastases are rare. The local aggressive nature of the tumour and the high recurrence rate may necessitate mutilating procedures. Optimal treatment consists of a complete microscopically controlled surgical excision with clear surgical margins. Key words: Syringomatous carcinoma, histopathology, immunohistochemistry, differential diagnosi

Surface Optical Waves at Air/Metal Interfaces: Surface Plasmon Polaritons

The surface plasmon resonance (SPR) phenomenon has been known for nearly five decades now; since then this method has made great advances in terms of instrumentation development and applications, and it still attracts researchers because of certain subtle issues that could benefit from it mainly detection and analysis of chemical and biochemical substances in different areas including medicine, environmental monitoring, biotechnology and drug and food monitoring. Our interest is focused on the use of this technique for studying thin coating and some application in nanophotonics. In this paper, we discuss the configuration of surface plasmons at air/metal interface by Atenuated total reflection (ATR) technique in the Kretchman configuration, and we present preliminary experimental results on surface plasmons at a Ag/air interface that we obtained in our laboratory.The surface plasmon resonance (SPR) phenomenon has been known for nearly five decades now; since then this method has made great advances in terms of instrumentation development and applications, and it still attracts researchers because of certain subtle issues that could benefit from it mainly detection and analysis of chemical and biochemical substances in different areas including medicine, environmental monitoring, biotechnology and drug and food monitoring. Our interest is focused on the use of this technique for studying thin coating and some application in nanophotonics. In this paper, we discuss the configuration of surface plasmons at air/metal interface by Atenuated total reflection (ATR) technique in the Kretchman configuration, and we present preliminary experimental results on surface plasmons at a Ag/air interface that we obtained in our laboratory

Baseline PI susceptibility by HIV-1 Gag-protease phenotyping and subsequent virological suppression with PI-based second-line ART in Nigeria

Objectives: Previous work showed that gag-protease-derived phenotypic susceptibility to PIs differed between HIV-1 subtype CRF02_AG/subtype G-infected patients who went on to successfully suppress viral replication versus those who experienced virological failure of lopinavir/ritonavir monotherapy as first-line treatment in a clinical trial. We analysed the relationship between PI susceptibility and outcome of second-line ART in Nigeria, where subtypes CRF02_AG/G dominate the epidemic. Methods: Individuals who experienced second-line failure with ritonavir-boosted PI-based ART were matched (by subtype, sex, age, viral load, duration of treatment and baseline CD4 count) to those who achieved virological response (‘successes’). Successes were defined by viral load <400 copies of HIV-1 RNA/mL by week 48. Full-length Gag-protease was amplified from patient samples for in vitro phenotypic susceptibility testing, with PI susceptibility expressed as IC50 fold change (FC) relative to a subtype B reference strain. Results: The median (IQR) lopinavir IC50 FC was 4.04 (2.49–7.89) for virological failures and 4.13 (3.14–8.17) for virological successes (P = 0.94). One patient had an FC >10 for lopinavir at baseline and experienced subsequent virological failure with ritonavir-boosted lopinavir as the PI. There was no statistically significant difference in single-round replication efficiency between the two groups (P = 0.93). There was a moderate correlation between single-round replication efficiency and FC for lopinavir (correlation coefficient 0.32). Conclusions: We found no impact of baseline HIV-1 Gag-protease-derived phenotypic susceptibility on outcomes of PI-based second-line ART in Nigeria

Hepatitis delta virus testing, epidemiology and management: A multicentre cross-sectional study of patients in London

AbstractBackgroundHepatitis delta virus (HDV) testing is recommended for all patients with hepatitis B virus (HBV) infection. HDV infection is associated with severe liver disease and interferon is the only available treatment.ObjectivesTo determine the rate of anti-HDV antibody testing in HBV patients; and to describe the epidemiology, clinical characteristics and management of HDV-infected patients at four hospitals in London.Study designThe anti-HDV testing rate was estimated by reviewing clinical and laboratory data. Cross-sectional data collection identified HDV-infected patients who had attended the study centres between 2005 and 2012.ResultsAt a centre with clinic-led anti-HDV testing, 40% (67/168) of HBV patients were tested. Recently diagnosed HBV patients were more likely to be screened than those under long-term follow-up (62% vs 36%, P=0.01). At a centre with reflex laboratory testing, 99.4% (3543/3563) of first hepatitis B surface antigen positive samples were tested for anti-HDV. Across the four study centres there were 55 HDV-infected patients, of whom 50 (91%) had immigrated to the UK and 27 (49%) had evidence of cirrhosis. 31 patients received interferon therapy for HDV with an end of treatment virological response observed in 10 (32%).ConclusionsThe anti-HDV testing rate was low in a centre with clinic-led testing, but could not be evaluated in all centres. The HDV-infected patients were of diverse ethnicity, with extensive histological evidence of liver disease and poor therapeutic responses. Future recommendations include reflex laboratory testing algorithms and a prospective cohort study to optimise the investigation and management of these patients

Three-Dimensional Multi-Relaxation Time (MRT) Lattice-Boltzmann Models for Multiphase Flow

In this paper, three-dimensional (3D) multi-relaxation time (MRT) lattice-Boltzmann (LB) models for multiphase flow are presented. In contrast to the Bhatnagar-Gross-Krook (BGK) model, a widely employed kinetic model, in MRT models the rates of relaxation processes owing to collisions of particle populations may be independently adjusted. As a result, the MRT models offer a significant improvement in numerical stability of the LB method for simulating fluids with lower viscosities. We show through the Chapman-Enskog multiscale analysis that the continuum limit behavior of 3D MRT LB models corresponds to that of the macroscopic dynamical equations for multiphase flow. We extend the 3D MRT LB models developed to represent multiphase flow with reduced compressibility effects. The multiphase models are evaluated by verifying the Laplace-Young relation for static drops and the frequency of oscillations of drops. The results show satisfactory agreement with available data and significant gains in numerical stability.Comment: Accepted for publication in the Journal of Computational Physic

Deep sequencing of HIV-1 reveals extensive subtype variation and drug resistance after failure of first-line antiretroviral regimens in Nigeria

BACKGROUND: Deep sequencing could improve understanding of HIV treatment failure and viral population dynamics. However, this tool is often inaccessible in low- and middle-income countries. OBJECTIVES: To determine the genetic patterns of resistance emerging in West African HIV-1 subtypes during first-line virological failure, and the implications for future antiretroviral options. PATIENTS AND METHODS: Participants were selected from a Nigerian cohort of people living with HIV who had failed first-line ART and subsequently switched to second-line therapy. Whole HIV-1 genome sequences were generated from first-line virological failure samples with Illumina MiSeq. Mutations detected at ≥2% frequency were analysed and compared by subtype. RESULTS: HIV-1 sequences were obtained from 101 participants (65% female, median age 30 years, median 32.9 months of nevirapine- or efavirenz-based ART). Thymidine analogue mutations (TAMs) were detected in 61%, other core NRTI mutations in 92% and NNRTI mutations in 99%. Minority variants (<20% frequency) comprised 18% of all mutations. K65R was more prevalent in CRF02_AG than G subtypes (33% versus 7%; P = 0.002), and ≥3 TAMs were more common in G than CRF02_AG (52% versus 24%; P = 0.004). Subtype G viruses also contained more RT cleavage site mutations. Cross-resistance to at least one of the newer NNRTIs, doravirine, etravirine or rilpivirine, was predicted in 81% of participants. CONCLUSIONS: Extensive drug resistance had accumulated in people with West African HIV-1 subtypes, prior to second-line ART. Deep sequencing significantly increased the detection of resistance-associated mutations. Caution should be used if considering newer-generation NNRTI agents in this setting

Strabisme aigu révélant une hypertension intracrânienne idiopathique associée à l’hormone de croissance Acute Strabismus Revealing Idiopathic Intracranial Hypertension Associated with Growth Hormone

Introduction : l’hypertension intracrânienne idiopathique associée l’hormone de croissance recombinant (rhGH)  est rare. Son  diagnostic nécessite l’élimination de  toutes les étiologies d’hypertension intracrânienne. But : attirer  l’attention des neuro-ophtalmologistes pédiatres  sur les différentes présentations cliniques et les  complications ophtalmologiques possible de cette pathologie.Observation : fille âgé de 11 ans suivie pour syndrome polyuropolydipsique et un retard staturopondéral secondaire à un déficit en hormone de croissance. L’exploration neuroradiologique a montré une  interruption de la tige pituitaire. Elle a été mise sous desmopressine depuis 5 ans remplacée  par   somatropine  durant les   6 derniers   mois.La patiente a présenté de façon aigue un tableau d’hypertension intracrânienne idiopathique. L’évolution a été  favorable dès le quinzième jour après arrêt initial de rhGH associé à l’acétazolamide.  A partir du troisième mois une  réintroduction  de l’hormone a été effectuée à des doses plus faibles sans récidive après un an de reculConclusion : l’hormone de croissance expose au risque d’HICI qui peut mettre en jeu  la fonction visuelle, s’elle n’est pas  traitée précocement. D’ou l’intérêt d’un suivi ophtalmologique chez les patients recevant ce traitemen