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Public health concerns exist surrounding the epidemic of the Zika virus (ZIKV) and the rapid growth of transplantation in developing countries, including endemic zones of active arbovirus transmission, as well as travel to such regions by potential organ donors and recipients. Few data exist regarding the clinical characteristics of ZIKVinfection in immunocompromised hosts. Laboratory screening protocols for transplantation to differentiate ZIKVinfections from other endemic viral diseases and for the detection of possible donor‐derived infection have not been stated. The diagnosis of ZIKVinfection remains a challenge, fueled by the lack of standardized commercially available diagnostic tests and validated reference diagnostic laboratories, as well as the limited duration of ZIKVviremia. In this small series, ZIKVinfection in renal and liver recipients presented without rash, conjunctivitis, or neurological symptoms, and with abnormal graft function, thrombocytopenia, and bacterial superinfection. We report the first case series of ZIKVinfection in solid organ recipients, with a description of clinical and laboratory features and therapeutic management. In this study, the authors describe the features of Zika infection in solid organ transplant. See the editorial from Blumberg and Fishman on page 599.

Crystalline carbon-based materials are intrinsically chemically inert and good heat conductors, allowing their applications in a great variety of devices. A technological step forward in heat dissipators production can be given by tailoring the carbon phase microstructure, tuning the CVD synthesis conditions. In this work, a rapid bottom-up synthesis of vertically aligned hybrid material comprising diamond thin platelets covered by a crystalline graphite layer was developed. A single run was designed in order to produce a high aspect ratio nanostructured carbon material favoring the thermal dissipation under convection-governed conditions. The produced material was characterized by multiwavelength Raman spectroscopy and electron microscopy (scanning and transmission), and the macroscopic heat flux was evaluated. The results obtained confirm the enhancement of heat dissipation rate in the developed hybrid structures, when compared to smooth nanocrystalline diamond films.

The effect of potassium permanganate (KMnO4) on the ripening process of papaya fruits by monitoring the ethylene emission rates is reported. The ethylene emission was monitored by a photoacoustic spectrometer. Two experimental conditions were applied, being one of them just putting the fruit alone inside the sampling chamber and the second, modifying the atmosphere by the presence of KMnO4. The use of the ethylene absorber reduces the autocatalytic process of ethylene during papaya fruit ripening. For 20 g of KMnO4the maximal intensity of the ethylene emission decreases by a factor two. Using the same amount of KMnO4, a reduction of about 2.2% in the concentration of ethylene for a mixture of 1ppmv of ethylene in synthetic air was observed.

Three different types of metallic bipolar plates (commercial stainless steels, Ni-based alloys, and nitride-coated steels) were investigated in terms of their interface contact resistance (ICR) and corrosion resistance in conditions typical of a proton exchange membrane fuel cell environment. The results showed that stainless steels are unsuitable because of the formation of nonconductive oxide that leads to high ICR. Ni-based alloys showed to be prone to corrosion in acidic medium, although they have an ICR comparable to commercially available graphite. Endurance tests carried out on nitride-coated stainless-steel specimens showed a low ICR and very good corrosion resistance of this material.

Three different types of metallic bipolar plates (commercial stainless steels, Ni-based alloys, and nitride-coated steels) were investigated in terms of their interface contact resistance (ICR) and corrosion resistance in conditions typical of a proton exchange membrane fuel cell environment. The results showed that stainless steels are unsuitable because of the formation of nonconductive oxide that leads to high ICR. Ni-based alloys showed to be prone to corrosion in acidic medium, although they have an ICR comparable to commercially available graphite. Endurance tests carried out on nitride-coated stainless-steel specimens showed a low ICR and very good corrosion resistance of this material.

Three different types of metallic bipolar plates (commercial stainless steels, Ni-based alloys, and nitride-coated steels) were investigated in terms of their interface contact resistance (ICR) and corrosion resistance in conditions typical of a proton exchange membrane fuel cell environment. The results showed that stainless steels are unsuitable because of the formation of nonconductive oxide that leads to high ICR. Ni-based alloys showed to be prone to corrosion in acidic medium, although they have an ICR comparable to commercially available graphite. Endurance tests carried out on nitride-coated stainless-steel specimens showed a low ICR and very good corrosion resistance of this material.

The effect of the intensity of the direct electrical current on the morphology and properties of superconducting BSCCO fibres grown by the electrically assisted laser floating zone (EALFZ) technique is presented. Stereological analysis and x-ray diffraction (XRD) pole plots reveal textural enhancement and crystal refinement as the main features when the current intensity increases. Analysis with scanning electron microscopy/energy dispersive x-ray spectroscopy also discloses changes in the phase fraction and nature. Improvement of the grain alignment is a result of the intensification of ionic migration in the solid–melt interface along the fibre axis. This leads to a net increase in the length of primary dendrites and a reduction in dendrite thickness and interdendritic spacing. The increase in current intensity also favours the vanishing of the 2201 phase and of the residual melt. The development of the 2223 phase during isothermal annealing is very pronounced for the EALFZ fibres grown under high current intensities due to the refinement of the reactant phases. The current transport capability after isothermal annealing of fibres is improved with application of a low current intensity (50mA), reflecting a net change of the morphological characteristics. However, when a high current intensity (200mA) is applied the unfavourable orientation of the newly formed 2223 crystals and the loss of crystallite quality of the 2212 phase due to intergrowth of 2223 structure in the original 2212 structure lead to poor superconducting properties.

The effect of the intensity of the direct electrical current on the morphology and properties of superconducting BSCCO fibres grown by the electrically assisted laser floating zone (EALFZ) technique is presented. Stereological analysis and x-ray diffraction (XRD) pole plots reveal textural enhancement and crystal refinement as the main features when the current intensity increases. Analysis with scanning electron microscopy/energy dispersive x-ray spectroscopy also discloses changes in the phase fraction and nature. Improvement of the grain alignment is a result of the intensification of ionic migration in the solid-melt interface along the fibre axis. This leads to a net increase in the length of primary dendrites and a reduction in dendrite thickness and interdendritic spacing. The increase in current intensity also favours the vanishing of the 2201 phase and of the residual melt. The development of the 2223 phase during isothermal annealing is very pronounced for the EALFZ fibres grown under high current intensities due to the refinement of the reactant phases. The current transport capability after isothermal annealing of fibres is improved with application of a low current intensity (50 mA), reflecting a net change of the morphological characteristics. However, when a high current intensity (200 mA) is applied the unfavourable orientation of the newly formed 2223 crystals and the loss of crystallite quality of the 2212 phase due to intergrowth of 2223 structure in the original 2212 structure lead to poor superconducting properties.

The application of an electric current of 200 mA through the molten zone of BSCCO superconducting fibres during laser floating zone processing constitutes an upgrade for improving the grain alignment. When a direct electric current (positively polarized fibre) passes through the solidification interface, the solidification conditions approach equilibrium, favouring the development of a higher amount of 2212 and 14/24 stable phases. The new electrically assisted laser floating zone (EALFZ) technique also improves the 2223 phase formation in fibres heat treated at high temperatures (860?°C). However, the 2223 crystals grow perpendicularly to the fibre axis at the interface between the 2212 and 14/24 phases, crossing the crystals of the main phase responsible for the current transport, cancelling the alignment effect. The resultant current density and critical temperature values were Jc77 K= 230 A cm?2and Tc= 85 K, respectively. When a lower heat treatment temperature was accomplished (820?°C), the 2223 transverse crystals do not develop and a higher current density value of Jc77 K= 510 A cm?2was achieved, although with a critical temperature of Tc= 90 K.

Abstract ß-spodumene (LiAlSi2O6) is one of the crystalline phase of the lithium aluminosilicate (LAS) glass-ceramics, having a low thermal expansion coefficient. The sol–gel process is an advantageous processing route for LAS materials, compared to melting, as it avoids lithium oxide losses and formation of undesired crystalline phases. It is very important to understand the crystallisation kinetics in order to assess the amount of the different crystalline phases formed for a given thermal cycle. This study reports the application of the non-isothermic method for evaluation of crystallization kinetic parameters, based on differential thermal analysis (DTA) experiments under constant heating rates (10, 12, 15 and 20°C min-1) up to 1000°C. The Johnson-Mehl-Avrami (JMA) theory, modified with distinct approaches, lead to Avrami coefficients, n, in the range of 2.1–2.4 and apparent activation energies, Ea, of 345–362 kJ mol-1. A simultaneous tridimensional and bidimensional crystal growth mechanism for a constant number of nuclei is proposed for ß -spodumene crystallization.

A new method for preparing highly stable Pt–Ru/C catalysts at low temperature is reported. Pt–Ru supported on high surface carbon was prepared from Pt(NH 3) 4Cl 2, RuNO(NO 3) x(OH) y and borohydride as a reducing agent. Simultaneous reduction of both metals was done by heat treatment and small and homogeneously dispersed catalyst particles were obtained with increased stability, as observed from solubility tests. Catalysis, XRD and TG data gave clear evidence of the different chemical states between the material produced and the commercially available sample. The electrochemical measurements showed that the novel catalysts have a performance similar to that of E-Tek samples.

We developed a positive selection method for recovering Marek's disease virus (MDV) recombinants. The Escherichia coli xanthine-guanine phosphoribosyltransferase gene (gpt), under the control of the major immediate-early promoter from cytomegalovirus, was inserted into the inverted repeats flanking the unique long (UL) region of a non-pathogenic serotype 2 MDV strain 281 MI/1. In a second demonstration of the usefulness of the positive selection system, the gpt gene was inserted into the inverted repeats flanking the unique short (US) region of the turkey herpesvirus (HVT) strain FC 126. The targeted insertion site in 281 MI/1 was in a previously established nonessential site for virus replication. The targeted insertion site for FC126, at the junction of the UL and US regions, is a nonessential site for in vitro replication of herpes simplex virus. Recombinant viruses were easily selected by incubating the transfected cells in mycophenolic acid (MPA)-containing medium. Purification of recombinants resulted from a series of trypsinization and sonication steps combined with the culturing of virus in MPA-containing medium to inhibit wildtype virus replication. This simple technique for recovering MDV and HVT recombinants should increase the efficiency of identifying nonessential sites and gene function analysis by insertional mutagenesis. Copyright 1993, 1999 Academic Press

We have analyzed the avian myeloblastosis virus proteins in two types of leukemic myeloblasts: established myeloblastic cell lines (DU 1765 and DU 11157) and leukemic myeloblasts obtained from the peripheral blood of a leukemic C/E Spafas chicken (no. 21957). Using monospecific antisera for immunoprecipitation and polyacrylamide gel electrophoresis, we have detected gag gene-related proteins in the myeloblasts. The DU 1765 and DU 11157 cells contained a p100 protein which possessed antigenic determinants of the viral proteins p27, p19, p15, and p12. The p100 was not found in leukemic myeloblasts from Spafas chickens, and pulse-chase experiments showed that the p100 was not a precursor for the viral proteins. However, the p100 is present in uninfected line 15 chicken embryos. A pr76-like protein was identified in DU 1765 cells but migrated slightly further into gels than the pr76 of Spafas-derived leukemic myeloblasts. The Spafas-derived myeloblasts produced a pr60, whereas the DU 1765 cells contained instead a related protein of 62,000 daltons. Using anti-avian myeloblastosis virus gp85 sera, a glycoprotein of 120,000 daltons (gp120) was detected in all the tested leukemic myeloblasts. The gp120 was also present, in low amounts, in uninfected embyonic spleen and yolk sac cells. The anti-gp85 sera also precipitated a 27,000-dalton protein (h27) in these same cells. Both the gp120 and h27 could not be detected in either uninfected or myeloblastosis-associated virus-infected fibroblasts. Limited peptide hydrolysis revealed that h27 is different from the viral structural protein p27. In conclusion, monospecific antisera for gag and env gene products of avian myeloblastosis virus did not precipitate any unique or aberrant avian myeloblastosis virus protein from leukemic myeloblasts.

Our objective was to identify an optimal single set of conditions for use in both indirect immunofluorescence assays (IFA) and in situ hybridization (ISH) to detect viral proteins and nucleic acids in avian lymphoid and neural tissues. Various fixatives were evaluated for use with IFA to detect turkey Herpesvirus (HVT) glycoprotein B (gB) and ISH to identify HVT mRNA in chicken tissues. A precipitating fixative (acetone) was compared to crosslinking fixatives [buffered glutaraldehyde-picric acid (BGPA), 10% formalin, and 4% paraformaldehyde] for both IFA and ISH using spleen, thymus, bursa, sciatic plexus, and brachial plexus of 28-day-old chickens. Four percent paraformaldehyde was found to be the optimal fixative for preservation of all chicken tissues examined with both IFA and ISH. Glass slide preparation, incubation temperatures, and tissue processing were each individually evaluated for ISH and IFA. Silylated slides provided the best retention of tissue sections for both procedures. For IFA, 37 degrees C was the ideal incubation temperature tested, whereas the optimal incubation temperature tested for ISH was 47 degrees C. Of the blocking agents compared, Evans blue dye prevented background fluorescence to a greater extent than either calf serum or bovine serum albumin. These findings provide a technical basis for investigations into various aspects of the molecular pathology of avian diseases.

The Vickers hardness of dense Si3N4 ceramics of the Si-Ce-Al-O-N system was investigated from room temperature to 1200°C. A sloppy decrease of hot hardness occurred above 850–900°C. A compensation law was observed between the pre-exponential factors of the hot-hardness dependence on the reciprocal of absolute temperature, and the values of the activation energy of hardness. This relationship shows that the low-temperature deformation mechanism, such as microplasticity, is competing in parallel with a grain-boundary diffusion-controlled creep process in the high-temperature range.

Gross and microscopic examinations of affected tissues from chickens of two commercial broiler breeder flocks aged 27 and 31 weeks revealed lesions of visceral lymphomas with bursal involvement in some chickens. Reticuloendotheliosis virus (REV), but not avian leukosis virus (ALV), was isolated from blood of affected chickens. Furthermore, DNA extracted from tumours tested positive for REV, but not for ALV or Marek's disease virus by polymerase chain reaction (PCR) test. Attempts to determine the source of REV infection included testing a commercial fowlpox (FP) vaccine used to immunize flocks at 7 days of age. Chicken-embryo fibroblasts inoculated with the FP vaccine tested positive for REV by PCR and immunofluorescent tests. REV was also isolated from plasma of pathogen-free chickens experimentally inoculated with FP vaccine at hatch; two of eight (25%) inoculated chickens developed lymphomas by 34 weeks of age. Antigenic characterization of REV isolated from commercial broiler breeder chickens and from FP vaccine, using monoclonal antibodies, revealed that both isolates belong to subtype 3 of REV. The data represent the first report of an outbreak of REV-induced lymphomas in commercial chickens. The data also indicate that the source of REV infection is an REV-contaminated commercial FP vaccine.

Previously, we isolated a replicon from a defective Marek's disease virus (MDV), analogous to defective herpes simplex viruses (amplicons). Defective viruses contain cis-acting elements required for DNA synthesis and virus propagation such as an origin of DNA replication and a packaging-cleavage signal site. In this report, the MDV replicon was utilized to locate an origin of MDV DNA replication. A comparison of MDV replicon sequences with other herpesvirus replication origin sequences revealed a 90-bp sequence containing 72% identity to the lytic origin (oris) of herpes simplex virus type 1. This 90-bp sequence displayed no similarity to betaherpesvirus or gammaherpesvirus replication origins. The 90-bp sequence is arranged as an imperfect palindrome centered around an A+T-rich region. This sequence also contains a 9-bp motif (5'CGTTCGCAC3') highly conserved in alphaherpesvirus replication origins. To test functionality of the 90-bp putative MDV replication origin, we conducted DpnI replication assays with subclones generated from the 4-kbp MDV replicon. A 700-bp MDV replicon subfragment containing the 90-bp putative MDV replication origin sequence is capable of replicating in chicken embryo fibroblast cells cotransfected with helper virus DNA. In conclusion, we identified a functional origin of DNA replication in MDV. Similarity of MDV origin sequences to those of alphaherpesviruses supports the current contention that MDV is more closely related to alphaherpesviruses than to gammaherpesviruses.

A biologically active myeloblastosis-associated virus (MAV) provirus was cloned from a bacteriophage recombinant library constructed from leukemic chicken myeloblast DNA. The restriction endonuclease map of this clone was consistent with that of a type 1 MAV (MAV-1). Interference assays of virus recovered from cultured chicken embryo fibroblasts after DNA transfection established that the provirus was infectious and confirmed that it belonged to avian retrovirus subgroup A (type 1). Antipeptide antibodies raised against the env-encoded carboxyl terminus of p48myb, the transforming protein of avian myeloblastosis virus, specifically immunoprecipitated the gp37env from quail cells transfected with MAV-1 proviral DNA but not from cells infected with MAV-2. This suggests that MAV-1 rather than MAV-2 is the progenitor helper virus from which avian myeloblastosis virus arose by the transduction of cellular proto-oncogene sequences.