Experimental transonic flutter characteristics of two 72 deg-sweep delta-wing models

Transonic flutter boundaries are presented for two simple, 72 deg. sweep, low-aspect-ratio wing models. One model was an aspect-ratio 0.65 delta wing; the other model was an aspect-ratio 0.54 clipped-delta wing. Flutter boundaries for the delta wing are presented for the Mach number range of 0.56 to 1.22. Flutter boundaries for the clipped-delta wing are presented for the Mach number range of 0.72 to 0.95. Selected vibration characteristics of the models are also presented

Agaricus blazei, supstrat za proizvodnju β-1,3-glukanaze s pomoću Trichoderma harzianum Rifai

Extracellular β-1,3-glucanase was produced by Trichoderma harzianum Rifai cultivated in the Agaricus blazei (Agaricus brasiliensis) extract as a substrate in submerged fermentation. A 2²-central composite factorial design was developed using the time of culture (x1/day) and Agaricus blazei extract concentration (x2/(g/L)) as variables, and the results were analyzed using response surface methodology (RSM). The results showed that the Agaricus blazei extract concentration was the most important variable in the production of β-1,3-glucanase, and the maximum β-1,3-glucanase activity (0.77 U/mL) was obtained in one day of cultivation. The β-glucan present in the cell wall of Agaricus blazei mushroom proved to be a good substrate for inducing the production of specific β-1,3-glucanase by Trichoderma harzianum Rifai.Ekstrakt gljive Agaricus blazei (Agaricus brasiliensis) upotrijebljen je kao supstrat za proizvodnju β-1,3-glukanaze submerznim uzgojem plijesni Trichoderma harzianum Rifai. Centralno složeni 22 faktorijalni dizajn razvijen je primjenom ovih varijabla: vrijeme uzgoja (x1/dan) i koncentracija ekstrakta Agaricus blazei (x2/(g/L)), a rezultati su analizirani metodom odzivnih površina (RSM). Rezultati pokazuju da je koncentracija ekstrakta Agaricus blazei najvažnija varijabla za proizvodnju β-1,3-glukanaze, a maksimalna je aktivnost enzima od 0,77 U/mL dobivena nakon prvoga dana uzgoja. β-Glukan u staničnoj stijenci gljive Agaricus blazei dobar je supstrat za proizvodnju specifične β-1,3-glukanaze s pomoću Trichoderma harzianum Rifai

Osmotic Dehydration as a Tool for Insdustrialization of Jabuticaba Peel (Myrciaria jabuticaba)

This study evaluated the osmotic dehydration of jabuticaba peel for use as a by-product, with development of new food products. Response surface methodology was used, considering temperature and sucrose concentration as independent variables, assessing their effects on water loss, solid gain, mass loss, and solid gain rate. Sucrose concentration had a greater influence on osmotic process. Temperature increase is necessary in osmotic dehydration, once it leads to tissue softening, which is essential for dehydration of jabuticaba peel. Therefore, the best osmotic dehydration conditions were set at 60°C and 70 °Brix. With respect to the physicochemical characterization of the bioactive compounds of dehydrated jabuticaba peel, considerable amounts of sugars, anthocyanins, and phenolic compounds were observed, besides the antioxidant potential. Thus, dehydration of jabuticaba peel is a viable alternative to minimize the waste generated during harvest, being a product with high nutritional value

A spontaneous increase in intracellular Ca2+ in metaphase II human oocytes in vitro can be prevented by drugs targeting ATP-sensitive K+ channels

STUDY QUESTION: Could drugs targeting ATP-sensitive K+ (KATP) channels prevent any spontaneous increase in intracellular Ca2+ that may occur in human metaphase II (MII) oocytes under in vitro conditions? SUMMARY ANSWER: Pinacidil, a KATP channel opener, and glibenclamide, a KATP channel blocker, prevent a spontaneous increase in intracellular Ca2+ in human MII oocytes. WHAT IS KNOWN ALREADY: The quality of the oocyte and maintenance of this quality during in vitro processing in the assisted reproductive technology (ART) laboratory is of critical importance to successful embryo development and a healthy live birth. Maintenance of Ca2+ homeostasis is crucial for cell wellbeing and increased intracellular Ca2+ levels is a well-established indicator of cell stress. STUDY DESIGN, SIZE, DURATION: Supernumerary human oocytes (n = 102) collected during IVF/ICSI treatment that failed to fertilize were used from October 2013 to July 2015. All experiments were performed on mature (MII) oocytes. Dynamics of intracellular Ca2+ levels were monitored in oocytes in the following experimental groups: (i) Control, (ii) Dimethyl sulfoxide (DMSO; used to dissolve pinacidil, glibenclamide and 2,4-Dinitrophenol (DNP)), (iii) Pinacidil, (iv) Glibenclamide, (v) DNP: an inhibitor of oxidative phosphorylation, (vi) Pinacidil and DNP and (vii) Glibenclamide and DNP. PARTICIPANTS/MATERIALS/SETTINGS/METHODS: Oocytes were collected under sedation as part of routine treatment at an assisted conception unit from healthy women (mean ± SD) age 34.1 ± 0.6 years, n = 41. Those surplus to clinical use were donated for research. Oocytes were loaded with Fluo-3 Ca2+-sensitive dye, and monitored by laser confocal microscopy for 2 h at 10 min intervals. Time between oocyte collection and start of Ca2+ monitoring was 80.4 ± 2.1 h. MAIN RESULTS AND THE ROLE OF CHANCE: Intracellular levels of Ca2+ increased under in vitro conditions with no deliberate challenge, as shown by Fluo-3 fluorescence increasing from 61.0 ± 11.8 AU (AU = arbitrary units; n = 23) to 91.8 ± 14.0 AU (n = 19; P <0.001) after 2 h of monitoring. Pinacidil (100 µM) inhibited this increase in Ca2+ (85.3 ± 12.3 AU at the beginning of the experiment, 81.7 ± 11.0 AU at the end of the experiment; n = 13; P = 0.616). Glibenclamide (100 µM) also inhibited the increase in Ca2+ (74.7 ± 10.6 AU at the beginning and 71.8 ± 10.9 AU at the end of the experiment; n = 13; P = 0.851. DNP (100 mM) induced an increase in intracellular Ca2+ that was inhibited by glibenclamide (100 µM; n = 9) but not by pinacidil (100 µM; n = 5). LIMITATIONS, REASONS FOR CAUTION: Owing to clinical and ethical considerations, it was not possible to monitor Ca2+ in MII oocytes immediately after retrieval. MII oocytes were available for our experimentation only after unsuccessful IVF or ICSI, which was, on average, 80.4 ± 2.1 h (n = 102 oocytes) after the moment of retrieval. As the MII oocytes used here were those that were not successfully fertilized, it is possible that they may have been abnormal with impaired Ca2+ homeostasis and, furthermore, the altered Ca2+ homeostasis might have been associated solely with the protracted incubation. WIDER IMPLICATIONS OF THE FINDINGS: These results show that maintenance of oocytes under in vitro conditions is associated with intracellular increase in Ca2+, which can be counteracted by drugs targeting KATP channels. As Ca2+ homeostasis is crucial for contributing to a successful outcome of ART, these results suggest that KATP channel openers and blockers should be tested as drugs for improving success rates of ART

LC-ESI-MS determination of quassinoids isobrucein B and neosergeolide in Picrolemma sprucei stem infusions

Infusions of the stems of Picrolemma sprucei (pseudonym: P. pseudocoffea) are used in the Amazon regions of Peru, Brazil and French Guiana as antimalarials among other uses. They contain the bitter quassinoids isobrucein B (1) and neosergeolide (2) that have important antimalarial and toxic properties among others. In this study, an LC-(+)-ESI-MS/MS method was developed and applied to the determination of 1 and 2 in a common remedy prepared by infusing 1 g of dry, powdered stems of P. sprucei in 1 L of boiling water. Isolated 1 and 2 were used in calibration ranges of 0.25 to 5 µg mL-1 and 0.5 to 10 µg mL-1, respectively, with the internal standard phloroglucinol at 4.0 µg mL-1. Good linearity, precision and accuracy were observed for both compounds. The concentrations of 1 and 2 in the stem infusions were found to be 60.1 and 774 µg L-1, respectively.Infusões dos caules de Picrolemma sprucei (pseudônimo: P. pseudocoffea) são principalmente utilizadas como antimaláricos em toda região amazônica. Desta espécie foram isolados os quassinoides isobruceína B e neosergeolida, os quais apresentam atividade antimalárica e citotóxica. Neste estudo, apresentamos o desenvolvimento de uma metodologia analítica por LC-(+)-ESI-MS/MS visando a determinação dos principais quassinoides desta espécie. O método desenvolvido foi empregado para análise de uma formulação artesanal (infusão de 1 g de matéria seca - caules pulverizados de P. sprucei em 1 L de água fervente). Padrões previamente isolados de isobruceína B e neosergeolida foram utilizados para a determinação da linearidade na faixa de calibração entre 0,25 to 5 µg mL-1 e 0,5 a 10 µg mL-1, respectivamente. Como padrão interno foi utilizada a substância fluoroglucinol na concentração de 4,0 µg mL-1. Ambos os compostos apresentaram boa linearidade, precisão e exatidão e as concentrações de isobruceína B e neosergeolida obtidas nas infusões foram de 60,1 e 774 µg L-1, respectivamente

Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection

Cross-reactive antibodies elicited by dengue virus (DENV) infection might affect Zika virus infection and confound serologic tests. Recent data demonstrate neutralization of Zika virus by monoclonal antibodies or human serum collected early after DENV infection. Whether this finding is true in late DENV convalescence (>6 months after infection) is unknown. We studied late convalescent serum samples from persons with prior DENV or Zika virus exposure. Despite extensive cross-reactivity in IgG binding, Zika virus neutralization was not observed among primary DENV infections. We observed low-frequency (23%) Zika virus cross-neutralization in repeat DENV infections. DENV-immune persons who had Zika virus as a secondary infection had distinct populations of antibodies that neutralized DENVs and Zika virus, as shown by DENV-reactive antibody depletion experiments. These data suggest that most DENV infections do not induce durable, high-level Zika virus cross-neutralizing antibodies. Zika virus–specific antibody populations develop after Zika virus infection irrespective of prior DENV immunity

Bordetella holmesii-like organisms isolated from Massachusetts patients with pertussis-like symptoms.

We isolated Bordetella holmesii, generally associated with septicemia in patients with underlying conditions, from nasopharyngeal specimens of otherwise healthy young persons with a cough. The proportion of B. holmesii-positive specimens submitted to the Massachusetts State Laboratory Institute increased from 1995 to 1998

A questão ambiental na origem do problema agrário brasileiro e o caso da região Sul.

A especificidade do processo de apropriação privada de terras públicas no Brasil, após 1850, é o ponto de origem dos problemas ambientais atuais no espaço rural, isso porque foi desse período em diante que a ausência de limites ambientais se tornou a regra principal da aliança entre a concentração fundiária e o progresso técnico aplicado à agricultura, comprometendo dramaticamente outras formas de acesso, bem como o uso produtivo ou não produtivo das terras e seus recursos naturais. O estudo de caso realizado na região sudoeste do Paraná, no Sul do Brasil, no entanto, demonstra que, apesar de uma estrutura agrária mais democrática, a regra de ausência de limites ambientais também é reiterada. Naquela região, o impulso básico à degradação ambiental deve-se ao fato de as estratégias de reprodução da agricultura familiar estarem estreitamente associadas aos imperativos do mercado exportador de grãos