Cherenkov Light Emission in Pure Cherenkov Emitters for Prompt Gamma Imaging.

Proton range verification (PRV) in proton therapy by means of prompt-gamma detection is a promising but challenging approach. High count rates, energies ranging between 1 MeV and 7 MeV, and a strong background complicate the detection of such particles. In this work, the Cherenkov light generated by prompt-gammas in the pure Cherenkov emitters TlBr, TlCl and PbF2 was studied. Cherenkov light in these crystals can provide a very fast timing signal with the potential to achieve very high count rates and to discern between prompt-gammas and background signals. Crystals of 1×1 cm2 and thicknesses of 1 cm, 2 cm, 3 cm and 4 cm were simulated. Different photodetector configurations were studied for 2.3 MeV, 4.4 MeV, and 6.1 MeV prompt-gammas. TlCl achieved the greatest number of detected Cherenkov photons for all energies, detector dimensions, and photodetector efficiency modeling. For the highest prompt-gamma energy simulated, TlCl yielded approximately 250 Cherenkov detected photons, using a hypothetical high-performance photodetector. Results show the crystal blocks of 1 cm × 1 cm × 1 cm have greater prompt-gamma detection efficiency per volume and a comparable average number of detected Cherenkov photons per event.

A guideline proposal for mice preparation and care in 18F-FDG PET imaging.

The experimental outcomes of small-animal positron emission tomography (PET) imaging with 18F-labelled fluorodeoxyglucose (18F-FDG) can be particularly compromised by animal preparation and care. Several works intend to improve research reporting and amplify the quality and reliability of published research. Though these works provide valuable information to plan and conduct animal studies, manuscripts describe different methodologies-standardization does not exist. Consequently, the variation in details reported can explain the difference in the experimental results found in the literature. Additionally, the resources and guidelines defining protocols for small-animal imaging are scarce, making it difficult for researchers to obtain and compare accurate and reproducible data. Considering the selection of suitable procedures key to ensure animal welfare and research improvement, this paper aims to prepare the way for a future guideline on mice preparation and care for PET imaging with 18F-FDG. For this purpose, a global standard protocol was created based on recommendations and good practices described in relevant literature.

New Enclosure for in vivo Medical Imaging of Zebrafish With Vital Signs Monitoring.

Lately, the use of zebrafish has gained increased interest in the scientific community as an animal model in preclinical research. However, there is a lack of in vivo imaging tools that ensure animal welfare during acquisition procedures. The use of functional imaging techniques, like Positron Emission Tomography (PET), in zebrafish is limited since it requires the animal to be alive, representing a higher instrumentation complexity when compared to morphological imaging systems. In the present work, a new zebrafish enclosure was developed to acquire in vivo images while monitoring the animal's welfare through its heartbeat. The temperature, dissolved oxygen, and pH range in a closed aquatic environment were tested to ensure that the conditions stay suitable for animal welfare during image acquisitions. The developed system, based on an enclosure with a bed and heartbeat sensors, was tested under controlled conditions in anesthetized fishes. Since the anesthetized zebrafish do not affect the water quality over time, there is no need to incorporate water circulation for the expected time of PET exams (about 30 min). The range of values obtained for the zebrafish heart rate was 88-127 bpm. The developed system has shown promising results regarding the zebrafish's heart rate while keeping the fish still during the long imaging exams. The zebrafish enclosure ensures the animal's well-being during the acquisition of in vivo images in different modalities (PET, Computer Tomography, Magnetic Resonance Imaging), contributing substantially to the preclinical research.

Spectroscopic analysis of LYSO:Ce crystals.

Rare earth orthosilicates are among the most widely used scintillator materials in the last decades. Particularly, lutetium-yttrium oxyorthosilicate (LYSO) is known to exhibit great potentialities in the field of radiation detectors for medical imaging. Consequently, an in-depth knowledge of the material properties is of utmost interest for the mentioned applications. In this work the spectroscopic properties of commercial cerium doped lutetium-yttrium oxyorthosilicate crystals (LYSO:Ce) were investigated by Raman spectroscopy, steady state photoluminescence, photoluminescence excitation and time resolved photoluminescence. Site selective excitation was used under steady state (325nm) and pulsed (266nm) conditions to separately investigate the temperature dependence of the 5d→4f Ce1 and Ce2 luminescence, allowing to establish the thermal quenching dependence of the Ce2 optical center. In the case of the Ce1 optical center, a luminescence quantum efficiency of 78% was obtained from 14K to room temperature with 266nm photon excitation.

Genetic divergence of common bean cultivars.

The aim of this study was to evaluate genetic divergence in the 'Carioca' (beige with brown stripes) common bean cultivar used by different institutions and in 16 other common bean cultivars used in the Rede Cooperativa de Pesquisa de Feijão (Cooperative Network of Common Bean Research), by using simple sequence repeats associated with agronomic traits that are highly distributed in the common bean genome. We evaluated 22 polymorphic loci using bulks containing DNA from 30 plants. There was genetic divergence among the Carioca cultivar provided by the institutions. Nevertheless, there was lower divergence among them than among the other cultivars. The cultivar used by Instituto Agronômico do Paraná was the most divergent in relation to the Carioca samples. The least divergence was observed among the samples used by Universidade Federal de Lavras and by Embrapa Arroz e Feijão. Of all the cultivars, 'CNFP 10104' and 'BRSMG Realce' showed the greatest dissimilarity. The cultivars were separated in two groups of greatest similarity using the Structure software. Genetic variation among cultivars was greater than the variation within or between the groups formed. This fact, together with the high estimate of heterozygosity observed and the genetic divergence of the samples of the Carioca cultivar in relation to the original provided by Instituto Agronômico de Campinas, indicates a mixture of cultivars. The high divergence among cultivars provides potential for the utilization of this genetic variability in plant breeding.

Identification of QTLs of resistance to white mold in common bean from multiple markers by using Bayesian analysis.

In this study, we identified simple sequence repeat, ampli-fied fragment length polymorphism, and sequence-related amplified poly-morphism markers linked to quantitative trait loci (QTLs) for resistance to white mold disease in common bean progenies derived from a cross between lines CNFC 9506 and RP-2, evaluated using the oxalic acid test and using Bayesian analysis. DNA was extracted from 186 F2 plants and their parental lines for molecular analysis. Fifteen experiments were car-ried out for phenotypic analysis, which included 186 F2:4 progenies, the F1 generation, the F2 generation, and the lines CNFC 9506, RP-2, and G122 as common treatments. A completely randomized experimental design with 3 replications was used in controlled environments. The adjusted means for the F2:4 generation were to identify QTLs by Bayesian shrink-age analysis. Significant differences were observed among the progenies for the reaction to white mold. The moving away method under the Bayes-ian approach was effective for identifying QTLs when it was not possible to obtain a genetic map because of low marker density. Using the Wald test, 25 markers identified QTLs for resistance to white mold, as well as 16 simple sequence repeats, 7 amplified fragment length polymorphisms, and 2 sequence-related amplified polymorphisms. The markers BM184, BM211, and PV-gaat001 showed low distances from QTLs related white mold resistance. In addition, these markers showed, signal effects with increasing resistance to white mold and high heritability in the analysis with oxalic acid, and thus, are promising for marker-assisted selection.

Properties of capsaicinoids for the control of fungi and oomycetes pathogenic to pepper.

Capsaicinoids are pungent compounds found in pepper (Capsicum spp.) fruits. Capsaicin showed antimicrobial activity in plate assays against seven isolates of five species of fungi and nine isolates of two species of oomycetes. The general trend was that oomycetes were more inhibited than fungi. Assays of capsaicin biosynthetic precursors suggest that the lateral chain of capsaicinoids has more inhibitory activity than the phenolic part. In planta tests of capsaicinoids (capsaicin and N-vanillylnonanamide) applied to the roots demonstrated that these compounds conferred protection against the pathogenic fungus Verticillium dahliae and induced both chitinase activity and expression of several defence-related genes, such as CASC1, CACHI2 and CABGLU. N-Vanillylnonanamide infiltrated into cotyledons confers systemic protection to the upper leaves of pepper against the fungal pathogen Botrytis cinerea. In wild-type tomato plants such cotyledon infiltration has no protective effect, but is effective in the Never-ripe tomato mutant impaired in ethylene response. A similar effect was observed in tomato after salicylic acid infiltration.

Induced resistance to Botrytis cinerea in Capsicum annuum by a Fusarium crude elicitor fraction, free of proteins.

Fusarium oxysporum f. sp. lycopersici (FOL) induces resistance in pepper against the airborne pathogen Botrytis cinerea and the soil-borne pathogen Verticillium dahliae. However, its practical use is limited due to its pathogenicity to other crops. In this study we tested several fractions of a heat-sterilised crude FOL-elicitor preparation to protect pepper against B. cinerea and V. dahliae. Only the protein-free insoluble fraction of the preparation reduced B. cinerea infection. However, none of the fractions reduce V. dahliae symptoms. The insoluble protein-free fraction induced expression of defence genes in the plant, namely a chitinase (CACHI2), a peroxidase (CAPO1), a sesquiterpene cyclase (CASC1) and a basic PR1 (CABPR1). Even though the CASC1 gene was not induced directly after treatment with the insoluble fraction in the leaves, it was induced after B. cinerea inoculation, showing a priming effect. The insoluble protein-free FOL-elicitor protected pepper against the airborne pathogen through a mechanism that involves induced responses in the plant, but different to the living FOL.

ABO-incompatible liver transplantation in acute liver failure: a single Portuguese center study.

INTRODUCTION: ABO-incompatible liver transplantation (ABOi LT) is considered to be a rescue option in emergency transplantation. Herein, we have reported our experience with ABOi LT including long-term survival and major complications in these situations. PATIENT AND METHODS: ABOi LT was performed in cases of severe hepatic failure with imminent death. The standard immunosuppression consisted of basiliximab, corticosteroids, tacrolimus, and mycophenolate mofetil. Pretransplantation patients with anti-ABO titers above 16 underwent plasmapheresis. If the titer was above 128, intravenous immunoglobulin (IVIG) was added at the end of plasmapheresis. The therapeutic approach was based on the clinical situation, hepatic function, and titer evolution. A rapid increase in titer required five consecutive plasmapheresis sessions followed by administration of IVIG, and at the end of the fifth session, rituximab. RESULTS: From January 2009 to July 2012, 10 patients, including 4 men and 6 women of mean age 47.8 years (range, 29 to 64 years), underwent ABOi LT. At a mean follow-up of 19.6 months (range, 2 days to 39 months), 5 patients are alive including 4 with their original grafts. One patient was retransplanted at 9 months. Major complications were infections, which were responsible for 3 deaths due to multiorgan septic failure (2 during the first month); rejection episodes (4 biopsy-proven of humoral rejections in 3 patients and 1 cellular rejection) and biliary. CONCLUSION: The use of ABOi LT as a life-saving procedure is justifiable in emergencies when no other donor is available. With careful recipient selection close monitoring of hemagglutinins and specific immunosuppression we have obtained acceptable outcomes.

Is the proton radius a player in the redefinition of the International System of Units?

It is now recognized that the International System of Units (SI units) will be redefined in terms of fundamental constants, even if the date when this will occur is still under debate. Actually, the best estimate of fundamental constant values is given by a least-squares adjustment, carried out under the auspices of the Committee on Data for Science and Technology (CODATA) Task Group on Fundamental Constants. This adjustment provides a significant measure of the correctness and overall consistency of the basic theories and experimental methods of physics using the values of the constants obtained from widely differing experiments. The physical theories that underlie this adjustment are assumed to be valid, such as quantum electrodynamics (QED). Testing QED, one of the most precise theories is the aim of many accurate experiments. The calculations and the corresponding experiments can be carried out either on a boundless system, such as the electron magnetic moment anomaly, or on a bound system, such as atomic hydrogen. The value of fundamental constants can be deduced from the comparison of theory and experiment. For example, using QED calculations, the value of the fine structure constant given by the CODATA is mainly inferred from the measurement of the electron magnetic moment anomaly carried out by Gabrielse's group. (Hanneke et al. 2008 Phys. Rev. Lett. 100, 120801) The value of the Rydberg constant is known from two-photon spectroscopy of hydrogen combined with accurate theoretical quantities. The Rydberg constant, determined by the comparison of theory and experiment using atomic hydrogen, is known with a relative uncertainty of 6.6×10(-12). It is one of the most accurate fundamental constants to date. A careful analysis shows that knowledge of the electrical size of the proton is nowadays a limitation in this comparison. The aim of muonic hydrogen spectroscopy was to obtain an accurate value of the proton charge radius. However, the value deduced from this experiment contradicts other less accurate determinations. This problem is known as the proton radius puzzle. This new determination of the proton radius may affect the value of the Rydberg constant . This constant is related to many fundamental constants; in particular, links the two possible ways proposed for the redefinition of the kilogram, the Avogadro constant N(A) and the Planck constant h. However, the current relative uncertainty on the experimental determinations of N(A) or h is three orders of magnitude larger than the 'possible' shift of the Rydberg constant, which may be shown by the new value of the size of the proton radius determined from muonic hydrogen. The proton radius puzzle will not interfere in the redefinition of the kilogram. After a short introduction to the properties of the proton, we will describe the muonic hydrogen experiment. There is intense theoretical activity as a result of our observation. A brief summary of possible theoretical explanations at the date of writing of the paper will be given. The contribution of the proton radius puzzle to the redefinition of SI-based units will then be examined.

Combined use of Paracoccidioides brasiliensis recombinant rPb27 and rPb40 antigens in an enzyme-linked immunosorbent assay for immunodiagnosis of paracoccidioidomycosis.

Paracoccidioidomycosis (PCM) is one of the most important endemic mycoses in Latin America; it's usually diagnosed by observation and/or isolation of the etiologic agent, Paracoccidioides brasiliensis, as well as by a variety of immunological methods, such as complement fixation and immunodiffusion. Although these approaches are useful, historically their sensitivity and specificity have often been compromised by the use of complex mixtures of undefined antigens. The use of combinations of purified, well-characterized antigens appears preferable and may yield good results. In the present study combinations of the previously described 27-kDa recombinant antigen (rPb27) and a recombinant 40-kDa-molecular-mass antigen (rPb40) from this fungus, that was identified by Goes et al. (2005) through the AST strategy as a homolog of Neurospora crassa calcineurin B, were used in an indirect enzyme linked immunosorbent assay (ELISA) for diagnosis and follow-up of patients with PCM. The complete coding cDNA of rPb40 and rPb27 were cloned into a pET-21a and a pET-DEST 42 plasmid, respectively, expressed in E. coli with a his-tag and purified by affinity chromatography. Among 109 PCM serum samples analyzed, a homogeneous IgG response to these proteins was observed. 62 serum samples from patients with other diseases, 18 from patients with other mycosis and 23 from healthy individuals were also studied. Detection of anti-rPb27 and anti-rPb40 antibodies in sera of patients with PCM by ELISA using a combination of the two purified proteins showed a sensitivity of 96% with a specificity of 100% in relation to control normal human sera and to sera from patients with other systemic mycosis and 93.5% to sera from patients with diverse infections. The use of this two proteins combination provided an excellent immunodiagnosis assay with great values of sensitivity and specificity, even in relation to sera from patients with other mycosis, making possible the standardization of a new methodology to diagnose this important mycosis, with a good confiability and reprodutibility.

Precision determination of the dpi<-->NN transition strength at threshold.

An unusual but effective way to determine at threshold the dpi<-->NN transition strength alpha is to exploit the hadronic ground-state broadening Gamma(1s) in pionic deuterium, accessible by x-ray spectroscopy. The broadening is dominated by the true absorption channel dpi(-)-->nn, which is related to s-wave pion production pp-->dpi(+) by charge symmetry and detailed balance. Using the exotic atom circumvents the problem of Coulomb corrections to the cross section as necessary in the production experiments. Our dedicated measurement finds Gamma(1s)=(1171(-49)(+23)) meV yielding alpha=(252(-11)(+5)) microb.

American cutaneous leishmaniasis in dogs from an endemic urban area in Cianorte municipality, Paraná State, Brazil

American cutaneous leishmaniasis (ACL) was investigated in dogs from an urban endemic area in Cianorte, Paraná state, Brazil. Of 169 studied dogs, none presented suspected ACL lesions. Eleven animals (6.6 percent) had anti-Leishmania braziliensis antibodies (titers > 40) detected by the immunofluorescent antibody test (IFAT) while four (2.4 percent) showed L. braziliensis-complex DNA by the polymerase chain reaction (PCR). Although no associations were found between IFAT or PCR results and age, sex, origin, free-roaming animals or length of residence at the address, the majority of IFAT- or PCR-positive dogs were from the urban area of the city and were allowed to roam freely beyond their neighborhood. The presence of anti-Leishmania braziliensis antibodies and L. braziliensis-complex DNA in dogs from this urban area near a native-forest park indicates the importance of following up on these dogs to confirm the ACL diagnosis.

EDXRF imaging of Pb in glazed ceramics using a micropattern gas detector.

A new system for energy-resolved X-ray fluorescence imaging using a microhole and strip plate (MHSP), a new type of micropattern gas detector (MPGD), is proposed. It works as a single photon counting detector with position and energy detection capability. The interaction of X-rays with the gas medium produces electrons via the photoelectric effect, and the number of electrons is proportional to the absorbed X-ray energy. These electrons are further multiplied in the MHSP. Position detection is achieved using the charge division method. The detector has an active area of 28 x 28 mm(2) and shows good position resolution, about sigma = 125 microm, an intrinsic energy resolution of about 14% FWHM for 5.9 keV X-rays, and a counting rate capability of up to 0.5 MHz. The system has shown good properties for energy-dispersive X-ray fluorescence (EDXRF) applications, since it allows efficient energy and position detection of fluorescence X-rays from multielemental samples. In this work, the system was used to study lead depth distributions in eighteenth-century Portuguese faiences from the Santa Clara-a-Velha monastery. The fluorescence images were obtained by irradiating the samples, with a pinhole placed between the sample and the detector to focus the radiation into the detector. The results are presented here, including the elemental map distributions for different samples.

Efeito do intervalo de recuperação entre séries de extensões isocinéticas de joelho em homens jovens destreinados / Effect of recovery interval between sets of isokinetic knee extensions among untrained young men

OBJETIVO: Avaliar o efeito de dois diferentes Intervalos de Recuperação (IR) entre séries de extensões isocinéticas de joelho no Pico de Torque (PT) e no Trabalho Total (TT) em jovens destreinados. MÉTODOS: Dezoito homens (24,22±2,58 anos; 80,42±11,41 kg) realizaram três séries de 10 extensões isocinéticas com o joelho direito a 60° e 180°/s. O IR entre as séries foram de 1 e 2 minutos, contrabalanceados entre os dois dias de teste, separados por, no mínimo, 48 horas. A taxa de trabalho-recuperação foi de 1:3 e 1:6 para 60°/s e 1:6 e 1:12 para 180°/s. Os voluntários não participavam de programas de treinamento resistido há pelo menos 6 meses. A análise estatística foi a ANOVA de medidas repetidas 2 x 3 [IR (1 e 2 minutos) x série (1ª, 2ª e 3ª)]. O nível de significância foi a<0,05. RESULTADOS: Tanto 1 como 2 minutos não conseguiram manter o PT e o TT ao longo das três séries (p<0,05). Porém, a 60°/s, 2 minutos de IR possibilitaram um melhor PT e TT na segunda e na terceira série que 1 minuto (p<0,05). Já a 180°/s, 2 minutos só foi superior (p<0,05) a 1 minuto na terceira série para o TT. CONCLUSÃO: O estudo indicou que durante um protocolo de treinamento isocinético, homens jovens necessitam mais de 2 minutos para recuperar totalmente o PT a 60°/s, e totalmente o TT a 60° e 180°/s. Entretanto, uma melhor recuperação do PT pode ser alcançada com uma taxa de trabalho-recuperação de 1:12 a 180°/s.

OBJECTIVE: To assess the effect of two recovery intervals (RIs) between sets of isokinetic knee extension exercises on peak torque (PT) and total work (TW), among untrained young men. METHODS: Eighteen men (24.22±2.58 years; 80.42±11.41 kg) performed three sets of ten isokinetic extensions of the right knee, at 60° and 180°/s. The RIs between the sets were one and two minutes long, spread over two test days separated by a minimum of 48 hours. The work-to-recovery ratio was 1:3 and 1:6 for 60°/s, and 1:6 and 1:12 for 180°/s. The subjects had not participated in any resistance training programs within the last six months. The statistical analysis consisted of 2 x 3 repeated-measures ANOVA [RI (one or two minutes) x set (1st, 2nd or 3rd)]. The significance level was a<0.05. RESULTS: Neither one minute nor two minutes RIs maintained the PT and TW throughout the three sets (p<0.05). However, at 60°/s, two minutes RIs enabled better PT and TW in the second and third sets than one minute RIs (p<0.05). At 180°/s, two minutes RIs were only better (p<0.05) than one minute RIs for TW in the third set. CONCLUSION: This study indicated that, during an isokinetic training protocol, young men require more than two minutes of RI for full PT recovery at 60°/s and full TW recovery at 60°/s and 180°/s. However, better PT recovery can be attained with a 1:12 work-to-recovery ratio at 180°/s.

Line shape of the microH(3p-1s) hyperfine transitions.

The (3p-1s) x-ray transition to the muonic hydrogen ground state was measured with a high-resolution crystal spectrometer. A Doppler effect broadening of the x-ray line was established which could be attributed to different Coulomb deexcitation steps preceding the measured transition. The assumption of a statistical population of the hyperfine levels of the muonic hydrogen ground state was directly confirmed by the experiment, and measured values for the hyperfine splitting can be reported. The results allow a decisive test of advanced cascade model calculations and establish a method to extract fundamental strong-interaction parameters from pionic hydrogen experiments.

Bagaço de mandioca (Manihot esculenta, Crantz) na dieta de vacas leiteiras: consumo de nutrientes / Cassava bagasse (Manihot esculenta, Crantz) in the diet of lactating cows: intake of nutrients

Avaliou-se o efeito da inclusão de diferentes níveis (0, 5, 10 e 15 por cento) de bagaço de mandioca à dieta de 12 vacas mestiças leiteiras Holandês x Zebu (composição racial com variação de » a ¾ de sangue H x Z) com 478,5kg de peso corporal médio e com 100 a 150 dias de lactação, distribuídas em três Quadrados Latinos 4 x 4. Foi avaliado o consumo de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), extrato etéreo (EE), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), carboidratos totais (CHT), carboidratos não-fibrosos (CNF) e nutrientes digestíveis totais (NDT). Forneceu-se silagem de capim-elefante como fonte de volumoso. As relações volumoso:concentrado utilizadas foram de 65,19:34,81; 61,59:38,41; 59,08:40,92 e 54,76:45,24. Formularam-se as dietas isoprotéicas e isoenergéticas. Houve aumento linear do consumo de MS, MO, PB, CHT, CNF e NDT, efeito quadrático do consumo de EE e redução do consumo de FDA com o aumento do BM, enquanto o consumo de FDN não diferiu entre os tratamentos.O bagaço de mandioca pode ser utilizado até o nível de 15 por cento de inclusão na dieta total de vacas mestiças leiteiras sem trazer transtornos fisiológicos ou nutricionais aos animais.

The effect of different inclusion levels (0, 5, 10, and 15 percent) of cassava bagasse to the diet of 12 Holstein x Zebu crossbred dairy cows (breed composition varying from » to ¾ H x Z blood), averaging 478.5kg body weight and 100 to 150 days in milk was evaluated. Cows were distributed in three 4 x 4 latin squares. The intake of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), acid detergent fiber (ADF), total carbohydrates (TC), non fiber carbohydrates (NFC), and total digestible nutrients (TDN) were evaluated. Elephant grass silage was provided as roughage source. The roughage:concentrate ratios were 65.19:34.81; 61.59:38.41; 59.08:40.92; and 54.76:45.24. Isonitogen and isoenergetic diets were formulated. There was a linear increase in DM, OM, CP, TC, NFC, and TDN intakes, quadratic effect of EE intake, and a reduction of ADF intake with the increase of the BM; while no diference among treatments was observed for NDF intake. The cassava bagasse can be used until 15 percent inclusion level in the total diet of crossbred dairy cows without physiological or nutritional damage.