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A new method is proposed to estimate the self-similarity exponent. Instead of applying finite moment(s) methods, a goodness-of-fit statistic is designed to test whether two rescaled sequences are drawn from the same distribution, which is the definition of self-similarity. The test is the empirical likelihood ratio, which is robust with respect to processes with dependence. We provide a closed formula for fractional Brownian motion and prove that the distance between two rescaled sequences is zero iff the scaling exponent equals the true one. According to our results, the method we propose can identify self-similarity and effectively estimate the corresponding exponent. [ABSTRACT FROM AUTHOR]

The last systemic financial crisis has reawakened the debate on the efficient nature of financial markets, traditionally described as semimartingales. The standard approaches to endow the general notion of efficiency of an empirical content turned out to be somewhat inconclusive and misleading. We propose a topological-based approach to quantify the informational efficiency of a financial time series. The idea is to measure the efficiency by means of the pointwise regularity of a (stochastic) function, given that the signature of a martingale is that its pointwise regularity equals 1 2. We provide estimates for real financial time series and investigate their (in)efficient behavior by comparing three main stock indexes. [ABSTRACT FROM AUTHOR]

Real-world financial dynamics daily do challenge the credibility of the Efficient Market Hypothesis, the pillar of the whole martingale-based modern financial theory stating that at any time asset prices discount all past information. As a matter of fact, the empirical evidence accumulated so far indicates that current models cannot explain the complexity of financial market movements, to the extent that a strand of skeptical thought, the Behavioral Finance, has been booming. The question whether a model exists which is able to make consistent the two paradigms is a living matter that financial markets demand to address. The paper deals with a parsimonious stochastic model able to include as special cases both market efficiency and "psychological" phenomena such as the underreaction and the overreaction, peculiar features of the behavioral finance. The great readability of the model, its capability to agree the controversial results provided by literature on efficient markets and the simplicity of the financial intuition it offers are discussed. [ABSTRACT FROM AUTHOR]

The 2010 reform of the legal regime regulating Palestinians’ access to the labour market in Lebanon ignited a heated debate among Lebanese, Palestinians, and international political actors. This article analyses the advocacy initiatives preceding the reform to answer the following question: what signifiers of Palestinian-ness have Palestinian political entrepreneurs mobilised? In a nutshell, it shows how a group of non-governmental organizations working with Palestinian refugees in Lebanon re-shaped the references to “Return” and “Dignity” in order to create an intellectual environment favourable to their demands for legal reform. However, these two signifiers not only concern the issue of the work-related rights of Lebanon’s Palestinians, but they also envisage a specific form of emplacement of the Palestinian community in that country. From this perspective, they are the constitutive elements of a “diasporic project” of emplacement in which Palestinians collectively exist in an in-between (imagined) space situated somewhere between their host society and their homeland. [ABSTRACT FROM PUBLISHER]

As an approach to determining the aetiology of chronic lymphocytic leukaemia ( CLL), we searched for a virus expressed in human CLL B-cells by combining high-throughput sequencing and digital subtraction. Pooled B-cell m RNA transcriptomes from five CLL patients and five healthy donors were sequenced with 454 Life Sciences technology. Human reads were excluded by BLAST ( Basic Local Alignment Search Tool) and BLAT ( BLAST-like alignment tool) searches. Remaining reads were screened with BLAST against viral databases. Purified B-cells from two CLL patients, with and without stimulation by phorbol-esters, were sequenced using Illumina technology to achieve depth of sequencing. Burrows- Wheeler Aligner mapping and BLAST searches were used for the Illumina data. Pyrosequencing resulted in about 400 000 reads per sample. No viral candidate could be found. Illumina single-end sequencing for 115 cycles yielded an average of 26 ± 2·5 million filtered reads per sample, of which 2·2 ± 0·6 million remained unmapped to human references. BLAST searches of these reads against viral and human databases assigned nine reads to an Epstein- Barr virus origin, in one sample following phorbol-ester stimulation. Other reads showing a putative viral origin were dismissed after further analysis. Despite an in-depth analysis of the CLL transcriptome reaching more than 100 million sequences, we have not found evidence for a putative viral candidate in CLL. [ABSTRACT FROM AUTHOR]

B-cell chronic lymphocytic leukemia (CLL) is characterized by the accumulation of long-lived circulating clonal leukemic B-cells, although the etiopathogenesis remains unclear. The incidence of CLL is variable in different regions around the world. While it is the most frequent chronic leukemia in Western countries, it has a low incidence in Asia. In this work we have investigated the immunoglobulin heavy chain gene rearrangements and mutational status in 80 Uruguayan patients with CLL, and compared these results with those obtained in other geographic regions. Our results demonstrate that Uruguayan patients with CLL display an IGHV gene usage which resembles that observed in Mediterranean countries and exhibits certain differences compared with Brazilian and Asian series, as expected, considering the ethnic basis of the Uruguayan population. This suggests that genetic influences could be important in the development and etiopathogenesis of CLL, but larger studies are necessary to substantiate this possibility. [ABSTRACT FROM AUTHOR]

The scaling properties of two alternative fractal models recently proposed to characterize the dynamics of stock market prices are compared. The former is the Multifractal Model of Asset Return (MMAR) introduced in 1997 by Mandelbrot, Calvet and Fisher in three companion papers. The latter is the multifractional Brownian motion (mBm), defined in 1995 by Péltier and Lévy Véhel as an extension of the very well-known fractional Brownian motion (fBm). We argue that, when fitted on financial time series, the partition function as well as the scaling function of the mBm, i.e. of a generally non-multifractal process, behave as those of a genuine multifractal process. The analysis, which concerns the daily closing prices of eight major stock indexes, suggests to evaluate prudently the recent findings about the multifractal behaviour in finance and economics. [ABSTRACT FROM AUTHOR]

In studying the scale invariance of an empirical time series a twofold problem arises: it is necessary to test the series for self-similarity and, once passed such a test, the goal becomes to estimate the parameter H0 of self-similarity. The estimation is therefore correct only if the sequence is truly self-similar but in general this is just assumed and not tested in advance. In this paper we suggest a solution for this problem. Given the process {X(t),t∈T}, we propose a new test based on the diameter δ of the space of the rescaled probability distribution functions of X(t). Two necessary conditions are deduced which contribute to discriminate self-similar processes and a closed formula is provided for the diameter of the fractional Brownian motion (fBm). Furthermore, by properly choosing the distance function, we reduce the measure of self-similarity to the Smirnov statistics when the one-dimensional distributions of X(t) are considered. This permits the application of the well-known two-sided test due to Kolmogorov and Smirnov in order to evaluate the statistical significance of the diameter δ, even in the case of strongly dependent sequences. As a consequence, our approach both tests the series for self-similarity and provides an estimate of the self-similarity parameter. [ABSTRACT FROM AUTHOR]

SSL, the lectin isolated from Salvia sclarea seeds, recognizes the Tn antigen (GalNAcα-O-Ser/Thr), a specific marker of many human carcinomas. Two-dimensional electrophoresis, amino-acid and amino-sugar analysis, and MALDI-TOF MS showed that SSL is an acidic (pI 5.5), 60-61-kDa dimeric glycoprotein composed of apparently identical subunits linked by a single disulfide bond. The apparent molecular mass of SSL in solution determined by equilibrium sedimentation analytical ultracentrifugation was 59 ± 9 kDa. This value did not change in the pH range 2.5-8.5, indicating that SSL does not associate into higher order structures. Tandem mass spectrometry and methylation analysis of N-glycans released from SSL by hydrazinolysis indicated that SSL possesses 2-3 glycosylation sites occupied with the typical plant glycans Manαl-6[(Manαl-3)(Xylβ1-2)]Manβ1-4-GlcNAcβ1-4( Fucαl-3)GlcNAc and [(Manα1-3/6)(Xylβ1-2)]Manβ1-4-GlcNAcβ1-4(Fucα1 -3)GlcNAc. The influence of adjacent Tn structures on the binding of two Tn-specific lectins (SSL and the isolectin B4 from Vicia villosa) and an anti-Tn monoclonal antibody (mAb 83D4) was evaluated using synthetic Tn glycopeptides. The binding of both lectins to the synthetic Tn glycopeptides was independent of the density of Tn structures. On the other hand, mAb 83D4 only reacted with glycopeptides displaying two or three consecutive Tn structures. [ABSTRACT FROM AUTHOR]

The Bovine Leukemia Virus (BLV) Envelope (Env) glycoprotein complex is instrumental in viral infectivity and shapes the host’s immune response. This study presents the production and characterization of a soluble furin-mutated BLV Env ectodomain (sBLV-EnvFm) expressed in a stable S2 insect cell line. We purified a 63 kDa soluble protein, corresponding to the monomeric sBLV-EnvFm, which predominantly presented oligomannose and paucimannose N-glycans, with a high content of core fucose structures. Our results demonstrate that our recombinant protein can be recognized from specific antibodies in BLV infected cattle, suggesting its potential as a powerful diagnostic tool. Moreover, the robust humoral immune response it elicited in mice shows its potential contribution to the development of subunit-based vaccines against BLV. [ABSTRACT FROM AUTHOR]

We combine two existing estimators of the local Hurst exponent to improve both the goodness of fit and the computational speed of the algorithm. An application with simulated time series is implemented, and a Monte Carlo simulation is performed to provide evidence of the improvement. [ABSTRACT FROM AUTHOR]

El artículo discurre sobre el estado de los refugiados somalíes durante principios del siglo 21. Los autores comentan sobre los pensamientos de los refugiados acerca de su regreso a su país natal. También se consideran las condiciones sociales y sanitarias experimentadas por los refugiados durante este periodo.

The article focuses on the August 2013 survey conducted by Médecins Sans Frontières (MSF) in its health facilities to highlight the living conditions and health issues experienced by refugees and their views regarding possible repatriation to Somalia. Living conditions were found to be worse than the ones experienced between 2007 and 2010, with problems in overcrowding, sanitation, and water. Only 20 percent wanted to go back to Somalia under present conditions.

• CoronaVac-BNT162b2 scheme shows significant increase in IgG levels after booster. • IgG levels drop ten weeks after booster but remain higher than those after priming. • Specific IgG levels correlate with neutralizing activity and Fc-mediated functions. Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has proven to be a successful strategy for prevent severe infections. CoronaVac and BNT162b2 are the most used vaccines worldwide, but their use in heterologous vaccination schedules is still subjected to evaluation. Fifty healthy individuals who received heterologous prime-boost vaccination with CoronaVac and BNT162b2 were enrolled in a post-vaccination serological follow-up longitudinal prospective study. We evaluated specific serum anti-receptor binding domain (RBD) IgG antibody levels, and their capacity to block RBD-ACE2 interaction with a surrogate neutralization assay. In 20 participants, we assessed antibody binding kinetics by surface plasmon resonance, and Fc-mediated functions by ADCC and ADCP reporter assays. Our baseline seronegative cohort, displayed seroconversion after two doses of CoronaVac and an important decrease in serum anti-RBD IgG antibodies levels 80 days post-second dose. These levels increased significantly early after the third dose with BNT162b2, but 73 days after the booster we found a new fall. Immunoglobulin functionalities showed a similar behavior. The heterologous prime-boost vaccination with CoronaVac and BNT162b2 generated an impressive increase in serum anti-RBD specific antibody levels followed by a drop. Nevertheless, these titers remained well above those found in individuals only vaccinated with CoronaVac in the same elapsed time. Serum IgG levels showed high correlation with antibody binding analysis, their capacity to block RBD-ACE2 interaction, and Fc-effectors mechanisms. Our work sheds light on the humoral immune response to heterologous vaccination with CoronaVac and BNT162b2, to define a post-vaccination correlate of protection against SARS-CoV-2 infection and to discuss the scheduling of future vaccine boosters in general population. [ABSTRACT FROM AUTHOR]

The retropepsin (PR) of the Bovine leukemia virus (BLV) plays, as in other retroviruses, a crucial role in the transition from the non-infective viral particle to the infective virion by processing the polyprotein Gag. PR is expressed as an immature precursor associated with Gag, after an occasional −1 ribosomal frameshifting event. Self-hydrolysis of PR at specific N- and C-terminal sites releases the monomer that dimerizes giving rise to the active protease. We designed a strategy to express BLV PR in E. coli as a fusion protein with maltose binding protein, with a six-histidine tag at its N-terminal end, and bearing a tobacco etch virus protease hydrolysis site. This allowed us to obtain soluble and mature recombinant PR in relatively good yields, with exactly the same amino acid composition as the native protein. As PR presents relative promiscuity for the hydrolysis sites we designed four fluorogenic peptide substrates based on Förster resonance energy transfer (FRET) in order to characterize the activity of the recombinant enzyme. These substrates opened the way to perform kinetic studies, allowing us to characterize the dimer-monomer equilibrium. Furthermore, we obtained kinetic evidence for the existence of a conformational change that enables the interaction with the substrate. These results constitute a starting point for the elucidation of the kinetic properties of BLV-PR, and may be relevant not only to improve the chemical warfare against this virus but also to better understand other viral PRs. [ABSTRACT FROM AUTHOR]

Abstract: The sustainability of a pay-as-you-go pension system strongly depends on the underlying demographic process determining the inverse old-age dependency ratio (the proportion of the active subpopulation to pensioners), considered as a sustainability index. Based on the classical Leslie population model, a dynamic demographic model including a controlled immigration is set up. A convergent algorithm is given which steers the population towards a demographic equilibrium with a better sustainability index, and at the same time minimizes the yearly immigration. In addition, simulations are provided for Italian data, comparing the demographic dynamics corresponding to different decision scenarios. [Copyright &y& Elsevier]

In this paper, we investigate a wireless communication scenario, where polarization multiplexing is exploited to increase the spectral efficiency. Independent modems over each polarization are considered, with communication links affected by phase noise and cross-polarization interference (XPI). We devise a novel per-polarization soft decision-directed iterative receiver with separate a posteriori probability-based synchronization and decoding. The synchronization algorithm relies on a minimum mean square error-based master–slave phase estimation followed by the cancellation of the XPI on the polarization of interest and requires no statistical knowledge of the phase noise process. The performance of the proposed iterative receiver is investigated for a pilot symbol-assisted low-density parity-check-coded quadrature amplitude modulation scheme. [ABSTRACT FROM AUTHOR]

Bovine leukaemia virus (BLV) is an oncogenic member of the genus Deltaretrovirus of the family Retroviridae. Recent studies revealed that BLV strains can be classified into six different genotypes and raised the possibility that another genotype may exist. In order to gain insight into the degree of genetic variability of BLV strains circulating in the South American region, a phylogenetic analysis was performed using gp51 env gene sequences. The results of these studies revealed the presence of seven BLV genotypes in this geographic region and the suitability of partial gp51 env gene sequences for phylogenetic inference. A significant number of amino acid substitutions found in BLV strains isolated in South America map to the second neutralization domain of gp51. A 3D molecular model of BLV gp51 revealed that these substitutions are located on the surface of the molecule. This may provide a selective advantage to overcome immune host neutralization. [ABSTRACT FROM AUTHOR]

An abstract of the article "In vitro characterisation of Bovine Leukemia Virus capsid protein self-assembly," by Gonzalo Obal and colleagues is presented.

An abstract of the research paper titled "Development of a Real time PCR Assay Using SYBR Green Chemistry for Bovine Leukemia Virus Detection," by Gonzalo Rama, Sergio Bianchi, Federico Carrion, Ana Meikle and others is presented.