Effect of pre-cooling on the shelf-life and quality of formosa papaya.

Papaya is a climacteric fruit, rapidly ripening after harvesting due to ethylene production and increased respiratory rate. This swift ripening results in softening of fruit tissues, shortening the fruit shelf life. Pre-cooling serves as an alternative to minimize fruit ripening and post-harvest losses by reducing metabolism. This study aimed to evaluate the effect of pre-cooling on the quality and conservation of Formosa 'Tainung I' papaya. Papayas at maturation stage II were obtained from a commercial orchard with conventional production. The experimental design was a completely randomized 4×6 split-plot scheme, with pre-cooling treatments (Control, without pre-cooling treatment; pre-cooling at 15 °C in a cold chamber; pre-cooling at 7 °C in a cold chamber; and forced-air cooling at 7 °C) in the plot, and days of storage (0, 7, 14, 21, 28, and 35 days) in the subplot. Pre-cooling effectively delayed the ripening and senescence of Formosa papaya, reducing the loss of green color and firmness. Regardless of the treatment used, chilling injury and incidence of fungi from the genus Fusarium and Alternaria limited the shelf life of Formosa 'Tainung I' papaya up to 21 days of storage. Additionally, the appearance of hardened regions in the pulp compromised the sensory quality of the fruits, necessitating further investigation into the causes of this disorder.

Maturation and antioxidant activity of 'Giombo' and 'Rama Forte' persimmons produced in the Brazilian semiarid.

The objective of this work was characterizing persimmons of the 'Giombo' and 'Rama Forte' cultivars harvested at different ripening stages in the Brazilian semiarid. Fruits were harvested at three ripening stages - green, semi-ripe and ripe - then evaluated for the following characteristics: fruit weight and diameter, skin and pulp color, fruit firmness, pulp pH, soluble solids content, titratable acidity, SSC/TA ratio, total soluble sugars, reducing sugars, astringency index, and the contents of tannin, vitamin C, carotenoid, ß-carotene, and total extractable polyphenols. Also, total antioxidant activity by the DPPH and ABTS methods and pectin methylesterase, and polygalacturonase enzyme activities were evaluated. Two experiments were carried out in a completely randomized design, one for each cultivar, with treatments consisting of different stages of maturation, with five replications of three fruits each. Data were submitted to analysis of variance and the differences between the means were compared using the Tukey test at 5% probability. Fruit firmness and soluble solids content did not vary between maturation stages for any of the cultivars. However, the skin color index increased with advancing maturation for both 'Giombo' and 'Rama Forte'. The astringency index, the content of total extractable polyphenols, soluble tannins and the antioxidant capacity were lower in fruits harvested at the ripe stage, for both cultivars. It can be concluded that persimmons of the 'Giombo' and 'Rama Forte' cultivars present better physicochemical quality characteristics when harvested when ripe, with a totally yellow skin.

Pressure-Induced Phase Transformations of Quasi-2D Sr3Hf2O7.

We present an abinitio study of the quasi-2D layered perovskite Sr3Hf2O7 compound, performed within the framework of the density functional theory and lattice dynamics analysis. At high temperatures, this compound takes a I4/mmm centrosymmetric structure (S.G. n. 139); as the temperature is lowered, the symmetry is broken into other intermediate polymorphs before reaching the ground-state structure, which is the Cmc21 ferroelectric phase (S.G. n. 36). One of these intermediate polymorphs is the Ccce structural phase (S.G. n. 68). Additionally, we have probed the C2/c system (S.G n. 15), which was obtained by following the atomic displacements corresponding to the eigenvectors of the imaginary frequency mode localized at the Γ-point of the Ccce phase. By observing the enthalpies at low pressures, we found that the Cmc21 phase is thermodynamically the most stable. Our results show that the I4/mmm and C2/c phases never stabilize in the 0-20 GPa range of pressure values. On the other hand, the Ccce phase becomes energetically more stable at around 17 GPa, surpassing the Cmc21 structure. By considering the effect of entropy and the constant-volume free energies, we observe that the Cmc21 polymorph is energetically the most stable phase at low temperature; however, at 350 K, the Ccce system becomes the most stable. By probing the volume-dependent free energies at 19 GPa, we see that Ccce is always the most stable phase between the two structures and also throughout the studied temperature range. When analyzing the phonon dispersion frequencies, we conclude that the Ccce system becomes dynamically stable only around 19-20 GPa and that the Cmc21 phase is metastable up to 30 GPa.

Ecological importance of lepidopteran defoliators on eucalyptus plantations based in faunistic and natural enemy analyses.

Areas planted with Eucalyptus urophylla S.T. Blake variety platyphylla F. Muell. (Myrtaceae) expand annually in most regions of Brazil. Many lepidopteran species defoliate this plant, but with damage varying per species. The objective of this study was to identify the pest status of lepidopteran defoliators based in the faunistic analysis of these insects and of their natural enemies on E. urophylla variety platyphylla plantations in a representative producing region of Brazil. Adult moths of lepidopterans and of their natural enemies were captured using a light trap, installed every two weeks, from September 2016 to August 2018. A total of 183, 10, three and 139 lepidopteran species was captured and classified as primary, secondary, without defined importance to eucalypt plants and non-identified with 1,419, seven, 465 and 876 individuals, respectively. Two primary pest species were constants, two accessories and six accidentals and all secondary ones were accidentals. Six primary pest species were common and dominant and four non-dominants. Faunistic indices indicated the main lepidopteran species that should be monitored in pest management programs. Seven hymenopteran species (65 individuals), three dipterans (49 individuals) and two hemipterans (four individuals) were the natural enemies collected using light traps. The monitoring of lepidopteran pests with light traps can contribute to the management and to reduce damage and control costs for these species, besides identifying natural enemies for biological control programs in Eucalyptus plantations.

Risk factors for developmental defects of enamel in children from southeastern Brazil.

INTRODUCTION: Developmental Defects of Enamel (DDEs) comprise qualitative and/or quantitative changes to the enamel during amelogenesis. The aetiology of DDE remains inconclusive. AIM: To determine the association of pre, peri, and postnatal factors with the presence of DDE. DESIGN: Cross-sectional study with 353 children (8 to 11 years-old) in a Brazilian town. METHODS: One calibrated dentist assessed DDE using the Developmental Defects of Enamel Index and a questionnaire collected medical and sociodemographic data. MAIN OUTCOMES: Children with at least one type of DDE were categorized into the DDE group. Subtypes of DDE were also recorded. RESULTS: 63.1% of children had at least one type of DDE. Diffuse opacity was present in 36.7%, demarcated opacity in 14.8%, and hypoplasia in 5.83% of the children. In multivariate analysis, demarcated opacities and hypoplasia were associated with birth weight ⟨ 2500g (OR = 4.82; 95% CI 1.23-1.95). CONCLUSION: Low birth weight predicted DDE.

Oral administration of Hsp65-producing Lactococcus lactis attenuates allergic asthma in a murine model.

AIMS: Allergic asthma is a chronic inflammatory lung disease characterized by a Th2-type immune response pattern. The development of nonspecific immunotherapy is one of the primary goals for the control of this disease. METHODS AND RESULTS: In this study, we evaluated the therapeutic effects of Lactococcus lactis-producing mycobacterial heat shock protein 65 (LLHsp65) in an ovalbumin (OVA)-induced allergic asthma model. OVA-challenged BALB/c mice were orally administrated with LLHsp65 for 10 consecutive days. The results demonstrate that LLhsp65 attenuates critical features of allergic inflammation, like airway hyperresponsiveness and mucus production. Likewise, the treatment decreases the pulmonary eosinophilia and the serum level of OVA-specific IgE. In addition to deviating immune responses towards Th1-cytokine profile, increase regulatory T cells, and cytokine levels, such as IL-6 and IL-10. CONCLUSIONS: Our results reveal that the mucosal immunotherapy of LLHsp65 significantly reduces the overall burden of airway allergic inflammation, suggesting a promising therapeutic strategy for allergic asthma treatment. SIGNIFICANCE AND IMPACT OF THE STUDY: This research reveals new perspectives on nonspecific immunotherapy based on the delivery of recombinant proteins by lactic acid bacteria to treat of allergic disorders.

Dynamical aspects of supercooled TIP3P-water in the grooves of DNA.

We investigate by molecular dynamics simulations the mobility of the water located at the DNA minor and major grooves. We employ the TIP3P water model, and our system is analyzed for a range of temperatures 190-300 K. For high temperatures, the water at the grooves shows an Arrhenius behavior similar to that observed in the bulk water. At lower temperatures, a departure from the bulk behavior is observed. This slowing down in the dynamics is compared with the dynamics of the hydrogen of the DNA at the grooves and with the autocorrelation functions of the water hydrogen bonds. Our results indicate that the hydrogen bonds of the water at the minor grooves are highly correlated, which suggests that this is the mechanism for the slow dynamics at this high confinement.

Responses of the weed Bidens pilosa L. to exogenous application of the steroidal saponin protodioscin and plant growth regulators 24-epibrassinolide, indol-3-acetic acid and abscisic acid.

The exogenous application of plant hormones and their analogues has been exploited to improve crop performance in the field. Protodioscin is a saponin whose steroidal moiety has some similarities to plant steroidal hormones, brassinosteroids. To test the possibility that protodioscin acts as an agonist or antagonist of brassinosteroids or other plant growth regulators, we compared responses of the weed species Bidens pilosa L. to treatment with protodioscin, brassinosteroids, auxins (IAA) and abscisic acid (ABA). Seeds were germinated and grown in agar containing protodioscin, dioscin, brassinolides, IAA and ABA. Root apex respiratory activity was measured with an oxygen electrode. Malondialdehyde (MDA) and antioxidant enzymes activities were assessed. Protodioscin at 48-240 µm inhibited growth of B. pilosa seedlings. The steroidal hormone 24-epibrassinolide (0.1-5 µm) also inhibited growth of primary roots, but brassicasterol was inactive. IAA at higher concentrations (0.5-10.0 µm) strongly inhibited primary root length and fresh weight of stems. ABA inhibited all parameters of seedling growth and also seed germination. Respiratory activity of primary roots (KCN-sensitive and KCN-insensitive) was activated by protodioscin. IAA and ABA reduced KCN-insensitive respiration. The content of MDA in primary roots increased only after protodioscin treatment. All assayed compounds increased APx and POD activity, with 24-epibrassinolide being most active. The activity of CAT was stimulated by protodioscin and 24-epibrassinolide. The results revealed that protodioscin was toxic to B. pilosa through a mechanism not related to plant growth regulator signalling. Protodioscin caused a disturbance in mitochondrial respiratory activity, which could be related to overproduction of ROS and consequent cell membrane damage.

Temperature of maximum density and excess properties of short-chain alcohol aqueous solutions: A simplified model simulation study.

We perform an extensive computational study of binary mixtures of water and short-chain alcohols resorting to two-scale potential models to account for the singularities of hydrogen bonded liquids. Water molecules are represented by a well studied core softened potential which is known to qualitatively account for a large number of water's characteristic anomalies. Along the same lines, alcohol molecules are idealized by dimers in which the hydroxyl groups interact with each other and with water with a core softened potential as well. Interactions involving non-polar groups are all deemed purely repulsive. We find that the qualitative behavior of excess properties (excess volume, enthalpy, and constant pressure heat capacity) agrees with that found experimentally for alcohols such as t-butanol in water. Moreover, we observe that our simple solute under certain conditions acts as a "structure-maker," in the sense that the temperature of maximum density of the bulk water model increases as the solute is added, i.e., the anomalous behavior of the solvent is enhanced by the solute.

Lattice model for water-solute mixtures.

A lattice model for the study of mixtures of associating liquids is proposed. Solvent and solute are modeled by adapting the associating lattice gas (ALG) model. The nature of interaction of solute/solvent is controlled by tuning the energy interactions between the patches of ALG model. We have studied three set of parameters, resulting in, hydrophilic, inert, and hydrophobic interactions. Extensive Monte Carlo simulations were carried out, and the behavior of pure components and the excess properties of the mixtures have been studied. The pure components, water (solvent) and solute, have quite similar phase diagrams, presenting gas, low density liquid, and high density liquid phases. In the case of solute, the regions of coexistence are substantially reduced when compared with both the water and the standard ALG models. A numerical procedure has been developed in order to attain series of results at constant pressure from simulations of the lattice gas model in the grand canonical ensemble. The excess properties of the mixtures, volume and enthalpy as the function of the solute fraction, have been studied for different interaction parameters of the model. Our model is able to reproduce qualitatively well the excess volume and enthalpy for different aqueous solutions. For the hydrophilic case, we show that the model is able to reproduce the excess volume and enthalpy of mixtures of small alcohols and amines. The inert case reproduces the behavior of large alcohols such as propanol, butanol, and pentanol. For the last case (hydrophobic), the excess properties reproduce the behavior of ionic liquids in aqueous solution.

Influence of ßS-Globin Haplotypes and Hydroxyurea on Arginase I Levels in Sickle Cell Disease.

Introduction. Sickle cell disease (SCD) is characterized by hemoglobin S homozygosity, leading to hemolysis and vasoocclusion. The hemolysis releases arginase I, an enzyme that decreases the bioavailability of nitric oxide, worsening the symptoms. The different SCD haplotypes are related to clinical symptoms and varied hemoglobin F (HbF) concentration. The aim of this study was to evaluate the impact of the ßS gene haplotypes and HbF concentration on arginase I levels in SCD patients. Methods. Fifty SCD adult patients were enrolled in the study and 20 blood donors composed the control group. Arginase I was measured by ELISA. The ßS haplotypes were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Statistical analyses were performed with GraphPad Prism program and the significance level was p < 0.05. Results. Significant increase was observed in the arginase I levels in SCD patients compared to the control group (p < 0.0001). The comparison between the levels of arginase I in three haplotypes groups showed a difference between the Bantu/Bantu × Bantu/Benin groups; Bantu/Bantu × Benin/Benin, independent of HU dosage. An inverse correlation with the arginase I levels and HbF concentration was observed. Conclusion. The results support the hypothesis that arginase I is associated with HbF concentration, also measured indirectly by the association with haplotypes.

Influence of disordered porous media on the anomalous properties of a simple water model.

The thermodynamic, dynamic, and structural behavior of a water-like system confined in a matrix is analyzed for increasing confining geometries. The liquid is modeled by a two-dimensional associating lattice gas model that exhibits density and diffusion anomalies, similar to the anomalies present in liquid water. The matrix is a triangular lattice in which fixed obstacles impose restrictions to the occupation of the particles. We show that obstacles shorten all lines, including the phase coexistence, the critical and the anomalous lines. The inclusion of a very dense matrix not only suppresses the anomalies but also the liquid-liquid critical point.

Reliability of measurements made on scanned cast models using the 3 Shape R 700 scanner.

OBJECTIVES: In dentistry, the latest technological advancements have been incorporated primarily into diagnostic tools such as virtual dental models. The aim of this study was to evaluate the reliability of measurements made on digital cast models scanned in the 3 Shape R 700 scanner (3 Shape, Copenhagen, Denmark) that uses a non-destructive laser beam to reproduce model surfaces so that the plaster model is not destroyed. METHODS: The sample consisted of 26 cast models, and 6 linear measurements were made on the cast models and compared with the same measurements on digital models. The measurements assessed were: (1) distance between mandibular canines; (2) distance between mandibular molars; (3) distance between canine and maxillary molar; (4) buccal-lingual diameter of maxillary central incisor; (5) distance between two points of the incisive papillae of maxillary and mandibular central incisors; and (6) distance between the buccal surface of the maxillary central incisor and the buccal surface of the mandibular antagonist (overjet). The Student's t-test or Wilcoxon test was used at 5% and the Lin's concordance test at 95% confidence interval. RESULTS: The overjet measurement was the only one that showed a statistically significant difference (p < 0.05). A high level of concordance was found for all measurements. CONCLUSIONS: The digital models obtained from the 3 Shape R 700 scanner are reliable and can be considered an alternative to cast models for performing measurements and analyses in orthodontic practice.

[Descriptive analysis of pelvic asymmetry in an asymptomatic population]. / Análisis descriptivo de la asimetría pélvica en una población asintomática.

INTRODUCTION: Pelvic tilt is clinically assessed based on its relationship with spinal conditions, but there is little evidence from the asymptomatic-population for comparison purposes. OBJECTIVE: To analyze an asymptomatic population focusing,on pelvic asymmetries using photogrammetry. MATERIAL AND METHODS: 92 subjects (18-35 years old) underwent marking of the anterior and posterior iliac spines and were photographed. Alcimage software was used to measure the pelvic tilt angle. Other tests included: the Kolmogorov normality test, t test, Wilcoxon test, and Pearson coefficient to measure the correlation. RESULTS: 11.96% of males had anteversion and 34.78% normality; 38.04% of females had anteversion and 15.22% normality. Angles between iliacs for bilateral tilt showed no difference, but a difference was seen with the predominance of one side. For unilateral tilt a difference between illacs was seen. Good correlation of predominance versus anteversion was observed, and correlation was poor for side angles. The rest showed a weak or non-significant correlation. CONCLUSION: Tilt cannot be used individually to characterize pelvic dysfunction or pathology.

Ion fluxes through nanopores and transmembrane channels.

We introduce an implicit solvent Molecular Dynamics approach for calculating ionic fluxes through narrow nanopores and transmembrane channels. The method relies on a dual-control-volume grand-canonical molecular dynamics (DCV-GCMD) simulation and the analytical solution for the electrostatic potential inside a cylindrical nanopore recently obtained by Levin [Europhys. Lett. 76, 163 (2006)]. The theory is used to calculate the ionic fluxes through an artificial transmembrane channel which mimics the antibacterial gramicidin A channel. Both current-voltage and current-concentration relations are calculated under various experimental conditions. We show that our results are comparable to the characteristics associated to the gramicidin A pore, especially the existence of two binding sites inside the pore and the observed saturation in the current-concentration profiles.

cDNA cloning, expression and characterization of a Boophilus microplus paramyosin.

The tick Boophilus microplus is a 1-host tick that causes important losses to bovine herds, and protective antigens are being investigated in order to develop vaccines that avoid the use of acaricides. Paramyosins are multi-functional invertebrate muscle proteins, whose roles may include host immunomodulation, and seem to be a prominent candidate in a schistosomiasis vaccine. We report here the cloning, expression and characterization of a B. microplus paramyosin (BmPRM). Sequence analysis of the full length coding sequence cDNA shows high identity to other arthropod paramyosin sequences, and the predicted molecular weight, pI and secondary structure are consistent with a typical paramyosin. Western-blot expression analysis indicates the presence of BmPRM in all tissues and developmental stages tested, but not in saliva. The recombinant protein (rBmPRM) was shown to bind both IgG and collagen. Possible implications of these activities with host evasion mechanisms are discussed.

Dredging and disposal of fine sediments in the state of Rio de Janeiro, Brazil.

Dredging is employed quite frequently in the state of Rio de Janeiro, especially for the installation and upkeep of commercial ports and rehabilitation of the hydraulic section of silted bodies of water. Until recently, all dredged material with no economic use was destined for marine disposal or stored at the edge of the water body. Since the 1990s, however, a new approach has been adopted for dredging as a result of pressure from the environmental organisations, encouraging closer interaction in Rio de Janeiro between the local and state public authorities and the universities on issues relating to licensing of this kind of activity. The recent experiments of the Civil and Ocean Engineering Programs of COPPE-UFRJ (Federal University of Rio de Janeiro) described herein are included in this context. The state of Rio de Janeiro has three bays, several coastal lagoon systems and a number of small and medium sized rivers in or close to urban areas, with a gentle slope as they near the sea. This is, then, a region highly susceptible to silting processes of water bodies, and therefore, to maintenance and/or environmental rehabilitation. As discussed in the article, fine and almost always organic sediments prevail, which is a considerable obstacle to the end disposal and possibility of reuse.

Criticality in confined ionic fluids.

A theory of a confined two-dimensional electrolyte is presented. The positive and negative ions, interacting by a 1/r potential, are constrained to move on an interface separating two solvents with dielectric constants epsilon(1) and epsilon(2). It is shown that the Debye-Hückel type of theory predicts that this two-dimensional Coulomb fluid should undergo a phase separation into a coexisting liquid (high-density) and gas (low-density) phases. We argue, however, that the formation of polymerlike chains of alternating positive and negative ions can prevent this phase transition from taking place.

Avaliação da qualidade de folhas de boldo-do-chile (Peumus boldus Molina) comercializadas em Curitiba, PR

Foi realizada a avaliação da qualidade de amostras de boldo-do-chile (Peumus boldus Molina) comercializadas na Região Metropolitana de Curitiba. Os resultados mostraram que todas as amostras são autênticas, mas os resultados das análises físico-químicas mostraram-se discrepantes em relação aos parametros da Farmacopéia Brasileira e outras bibliografias de referência.

Samples of boldo-do-chile (Peumus boldus Molina) commercialized at the metropolitan area of Curitiba/PR were evaluated to establish their quality control patterns. The results showed that all samples are authentic but the data obtained for the physico-chemical parameters differ from those related at the Brazilian Pharmacopoeia IV ed.

[Approach in acute respiratory tract disfunction] / Abordagem na disfunção respiratória aguda.

OBJECTIVE: To present a review of the current diagnostic and therapeutic approach to the major conditions found in pediatric emergency department, which course with acute respiratory tract disfunction, stressing some clinical and epidemiological characteristics that are useful to the pediatrician in the differential diagnosis.METHODS: Outstanding articles related to the subject were selected after literature review of the last 20 years, using Md Consult, Medline and Lilacs databases.RESULTS: Many diseases can produce respiratory disfunction. Taking into account only those with acute symptoms, infectious and/or inflammatory causes predominate. History, examination findings and at least a chest X-ray are almost always sufficient for the diagnosis, but, sometimes other complimentary tests are necessary.CONCLUSIONS: If not properly treated, acute respiratory emergencies can result in significant morbidity and mortality. Any pediatrician taking part in an emergency team has to obtain respiratory management skills and knowledge concerning distinctive aspects and severity estimation of the several respiratory diseases.