Programmable axial apodizing and hyperresolving amplitude filters with a liquid-crystal spatial light modulator

Amplitude-transmitting filters for apodizing and hyperresolving applications can be easily implemented by use of a two-dimensional programmable liquid-crystal spatial light modulator operating in a transmission-only mode. Experimental results are in excellent agreement with theoretical predictions. This approach can permit the analysis of various filter designs and can allow the filters to be changed rapidly to modify the response of an optical system

Selective IgA deficiency and presumptive polyclonal spike in the beta fraction in a dog with leishmaniosis

A 1-year-old, entire, crossbred, female dog examined for apathy, lethargy, unilateral nosebleed of 2-month duration and the presence of symmetrical ulcerative dermatitis (small ulcers covered by a haemorrhagic crust and surrounded by alopecia on the tip of the ear pinna). Laboratory alterations included anaemia and hyperglobulinemia with a presumptive polyclonal spike in the beta fraction. High antibody levels to Leishmania infantum were detected by enzyme-linked immunosorbent assay. An anti-Leishmania therapeutic protocol was established and a reduction of the anti-Leishmania antibodies was detected by an end point sera dilution enzyme-linked immunosorbent assay during the first weeks of therapeutic protocol, while C-reactive protein concentration was reduced during the period of time when meglumine antimoniate was administered. A good clinical response to the treatment was detected after initiating the anti-Leishmania treatment. Quantitative serology is useful in the short-term, because using a two-fold serial dilution technique correlates with the clinical response. © 2022 British Veterinary Association

Combined Mueller and Jones matrix method for the evaluation of the complex modulation in a liquid-crystal-on-silicon display

We apply the polar decomposition of the Mueller matrix describing a liquid-crystal-on-silicon display to identify the diattenuator, depolarizer, and retarder contributions as a function of the gray level. The retarder contribution is expressed in terms of the equivalent Jones matrix to apply previous techniques to evaluate the phase modulation. This allows searching for optimized polarization configurations for phase- or amplitude-only modulation responses. We present results for =633 nm showing a phase-only modulation up to 2 rad and flat intensity modulation.Fil: Moreno, I.. Universidad Miguel Hernandez - Elche; EspañaFil: Lizana, A.. Universidad Autonoma de Barcelona. Facultad de Física; EspañaFil: Campos, J.. Universidad Autonoma de Barcelona. Facultad de Física; EspañaFil: Márquez, A.. Universidad de Alicante. Facultad de Ciencias; EspañaFil: Iemmi, Claudio César. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Yzuel, M. J.. Universidad Autonoma de Barcelona. Facultad de Física; Españ

Integration in the Fourier domain for restoration of a function from its slope : comparison of four methods

Altres ajuts: European Community project CTB556-01-4175.In some measurement techniques the profile, f(x), of a function should be obtained from the data on measured slope f'(x) by integration. The slope is measured in a given set of points, and from these data we should obtain the profile with the highest possible accuracy. Most frequently, the integration is carried out by numerical integration methods [Press et al., Numerical Recipes: The Art of Scientific Computing (Cambridge U. Press, Cambridge, 1987)] that assume different kinds of polynomial approximation of data between sampling points. We propose the integration of the function in the Fourier domain, by which the most-accurate interpolation is automatically carried out. Analysis of the integration methods in the Fourier domain permits us to easily study and compare the methods' behavior

Evaluation of the performance of three serological tests for diagnosis of Leishmania infantum infection in dogs using latent class analysis

Canine leishmaniasis (CanL) is a disease caused by Leishmania infantum. Serological methods are the most common diagnostic techniques used for the diagnosis of the CanL. The objective of our study was to estimate the sensitivity and specificity of one in-house ELISA kit (ELISA UNIZAR) and three commercially available serological tests (MEGACOR Diagnostik GmbH) including an immunochromatographic rapid test (FASTest LEISH®), an immunofluorescent antibody test (MegaFLUO LEISH®) and an enzyme-linked immunosorbent assay (MegaELISA LEISH®), using latent class models in a Bayesian analysis. Two hundred fifteen serum samples were included. The highest sensitivity was achieved for FASTest LEISH® (99.38%), ELISA UNIZAR (99.37%), MegaFLUO LEISH® (99.36%) followed by MegaELISA LEISH® (98.49%). The best specificity was obtained by FASTest LEISH® (98.43%), followed by ELISA UNIZAR (97.50%), whilst MegaFLUO LEISH® and MegaELISA LEISH® obtained the lower specificity (91.94% and 91.93%, respectively). The results of present study indicate that the immunochromatographic rapid test evaluated FASTest LEISH® show similar levels of sensitivity and specificity to the quantitative commercial tests. Among quantitative serological tests, sensitivity and specificity were similar considering ELISA or IFAT techniques. A leishmaniose canina (Lcan) é uma doença causada pela Leishmania infantum. Os métodos sorológicos são as técnicas diagnósticas mais utilizadas para o diagnóstico da leishmaniose canina. O objetivo do nosso estudo foi estimar a sensibilidade e a especificidade de um kit ELISA interno (ELISA UNIZAR) e de três testes sorológicos disponíveis comercialmente, feitos pelo mesmo fabricante (MEGACOR Diagnostik GmbH), incluindo um teste rápido imunocromatográfico (FASTest LEISH®), um teste de anticorpos imunofluorescentes (Megafluo LEISH®) e um ensaio de imunoabsorção enzimática (Megaelisa LEISH®), utilizando-se modelos de classe latentes numa análise bayesiana. Foram incluídas duzentas e quinze amostras de soro. A maior sensibilidade foi alcançada para Fastest LEISH® (99, 38%), ELISA UNIZAR (99, 37%), Megafluo LEISH® (99, 36%) seguida por Megaelisa LEISH® (98, 49%). A melhor especificidade foi obtida por FASTest LEISH® (98, 43%), seguida por ELISA UNIZAR (97, 50%), enquanto Megafluo LEISH® e Megaelisa LEISH® obtiveram a menor especificidade (91, 94% e 91, 93%, respectivamente). Os resultados do presente estudo indicam que o teste rápido imunocromatográfico, avaliado por FASTest LEISH® mostra níveis similares de sensibilidade e especificidade aos testes comerciais quantitativos incluídos. Entre os testes sorológicos quantitativos, a sensibilidade e a especificidade foram semelhantes, considerando-se as técnicas de ELISA ou IFI

Clinical leishmaniosis in a domestic ferret (Mustela putorius furo) treated with miltefosine plus allopurinol: Serological and clinical follow-up

The published information on the treatment of mustelid leishmaniosis is extremely scarce because there are only two case reports available. In one case, a domestic ferret (Mustela putorius furo) was treated with a combination of meglumine antimoniate plus allopurinol and, in the other case, a therapeutic regimen with allopurinol was administrated to a Eurasian otter (Lutra lutra). This article describes for the first time a combined therapeutic protocol with miltefosine (2 mg/kg once a day during 28 days per os), and allopurinol (10 mg/kg twice a day PO sine die) in a domestic ferret with splenomegaly, lymphadenomegaly and a facial pyogranulomatous dermatitis, with a moderate level of antibodies to Leishmania infantum. © 2021 Elsevier B.V

A cross-sectional study of Leishmania infantum infection in stray cats in the city of Zaragoza (Spain) using serology and PCR

Background: Feline leishmaniosis is a vector-borne parasitic disease caused by Leishmania spp. Leishmania infection in dogs is prevalent in the Mediterranean basin, but in other animals, such as cats, it could also play a role in the epidemiology of the disease. Information on the geographical distribution and epidemiological features of L. infantum infection in cats is scarce, particularly in urban stray cats living in regions where canine leishmaniosis is endemic. As diagnosis can be challenging, combining different serological and molecular methods is a useful approach. Our aim was to investigate the prevalence of infection of L. infantum in apparently healthy stray cats in an endemic region of Spain (Zaragoza city) using serological and molecular methods, and to compare the results of the different techniques. Methods: The prevalence of Leishmania infection was studied in stray cats captured in urban and peri-urban areas of Zaragoza. Blood was collected from each animal for serology and molecular analysis. Three serological methods, namely the immunofluorescent antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA) and western blot (WB), were used to detect L. infantum antibodies and a real-time PCR (qPCR) assay was used to detect L. infantum DNA. The results were analyzed by Fisher’s exact test and Cohen’s kappa statistic (¿) to assess the level of agreement between the diagnostic techniques. Results: Serological analysis of blood samples from 180 stray cats revealed 2.2% (4/179) Leishmania infection positivity by IFAT, 2.8% (5/179) by ELISA and 14.5% (26/179) by WB. Leishmania DNA was detected by qPCR in 5.6% (10/179) of the cats. Sixteen cats (8.9%) tested positive by only one serological technique and four tested positive by all three serological methods used. The overall rate of infected cats (calculated as the number of cats seropositive and/or qPCR positive) was 15.6%, and only two cats tested positive by all the diagnostic methods. A significant association was found between male cats and a positive qPCR result. Comparison of the techniques revealed a fair agreement in seropositivity between blood qPCR and IFAT (¿ = 0.26), blood qPCR and ELISA (¿ = 0.24), WB and ELISA (¿ = 0.37) and WB and IFAT (¿ = 0.40). The highest agreement between seropositive results was between IFAT and ELISA (¿ = 0.89), and the lowest was between blood qPCR and WB (¿ = 0.19). The prevalence of the feline leukemia virus antigen was 4.49% (8/178 cats) and that of the feline immunodeficiency virus (FIV) antibody was 6.74% (12/178), while co-infection with both retroviruses was observed in one female cat (1/178). Leishmania ELISA and IFAT seropositivity were statistically associated with FIV status by the chi-square test. Conclusions: The results obtained in this study, using serological tests and qPCR, indicate the existence of L. infantum asymptomatic infection in apparently healthy stray cats in the city of Zaragoza, an endemic area in Spain. [Figure not available: see fulltext.

Wavelength dependence of polarimetric and phase-shift characterization of a liquid crystal on silicon display

We present a full characterization of a liquid-crystal-on-silicon (LCoS) display, including a polarimetric analysis based on the Mueller-Stokes formalism, and a phase shift modulation calibration. Results for different wavelengths are compared. The goal of this work is two fold. On one side, previous papers dealing with the illumination wavelength 633 nm have shown that LCoS produce a non negligible amount of depolarized light. This may have a negative impact in certain applications. Here we want to establish how this depolarization varies with the wavelength. On the other side, to use the LCoS as a spatial light modulator (SLM) we need to obtain optimal configurations enabling for phase-only or for amplitude-only modulation. Here we show how phase-only modulation is obtained, and how it evolves with the wavelength. In principle, for shorter wavelengths the phase modulation depth increases and the energy throughput may also be increased. However, these phase-only configurations may be partially degraded by the presence of depolarization at certain gray levels. Thus, the Mueller-Stokes formalism is necessary to get a full picture of the performance exhibited by the LCoS at each wavelengt

First report on natural infection with Leishmania infantum in a domestic ferret (Mustela putorius furo) in Spain

A pet domestic ferret (Mustela putorius furo) with a papular lesion involving the right pinna was diagnosed with chronic pyogranulomatous dermatitis by histopathologic examination. Intralesional, intracytoplasmic oval microorganisms compatible with Leishmania spp. or Histoplasma spp. were observed in macrophages and multinucleate giant cells. Leishmania infantum (L. infantum) infection was diagnosed by PCR, culture in Novy-MacNeal-Nicolle medium, and immunohistochemistry. Abnormal clinicopathological results included increased alanine transferase, alkaline phosphatase, serum gamma glutamyl transferase and polyclonal gammpathy. Anti-Leishmania antibodies were detected by enzyme-linked immunosorbent assay, immunofluorescence antibody test and western blot using L. infantum antigen. Immunoreactivity against the 16 kDa specific L. infantum antigen fraction was observed by western blot. PCR performed in blood samples obtained from this patient after positive parasite isolation detected L. infantum DNA. To the authors' knowledge, this is the first diagnosis and isolation of L. infantum in a domestic ferret naturally infected in an endemic region (Spain) where canine and feline leishmaniosis is frequently detected. According to these findings, ferrets should be included as potential reservoir hosts of L. infantum. Future investigations should analyze the epidemiological role of ferrets in L. infantum infection including the prevalence of infection

Tailoring the depth of focus for optical imaging systems using a Fourier transform approach

We show how to tailor the depth of focus for an optical system using pupil functions obtained from a Fourier transform approach. These complex amplitude and phase pupil functions are encoded onto a single liquid-crystal spatial light modulator. Experimental results show excellent agreement with theory and indicate the power of this approach