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  • Author: A.I. Popov x
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New Records of Hoverflies (Diptera, Syrphidae) from Ukraine. III. Pipizinae and Syrphinae

Abstract

Five species of hoverflies of the subfamilies Pipizinae and Syrphinae: Pipiza accola Violovitsh, 1985, Platycheirus nielseni Vockeroth, 1990, P. occultus Goeldlin, Maibach and Speight, 1990, Epistrophe olgae Mutin, 1990, and Xanthogramma laetum (Fabricius, 1794) are recorded from Ukraine for the first time. Distributions of these species are summarized and diagnoses of the species are provided.

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New Records of Hoverflies (Diptera, Syrphidae) from Ukraine. II. Brachyopini and Merodontini

Abstract

Seven hoverfly species of the tribes Brachyopini and Merodontini (subfamily Eristalinae): Brachyopa maculipennis Thompson, 1980, B. plena Collin, 1939, B. vittata (Zetterstedt, 1843), Myolepta obscura Becher, 1882, Orthonevra geniculata (Meigen, 1830), Merodon moenium (Wiedemann in Meigen, 1822) and Psilota atra (Fallén, 1817) are recorded from Ukraine for the first time. Distributions of these species are summarized and diagnoses of the species are provided.

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New Records of Hoverflies (Diptera, Syrphidae) from Ukraine. I. Milesiini and Rhingiini

Abstract

Five species of hoverflies of the subfamily Eristalinae (tribes Milesiini and Rhingiini): Criorhina floccosa (Meigen, 1822), Chalcosyrphus eunotus (Loew, 1873), Pocota personata (Harris, 1780), Cheilosia psilophthalma Becker, 1894 and C. reniformis Hellén, 1930, are recorded from Ukraine for the first time. Distribution of these species is discussed and diagnoses of Cheilosia species are provided.

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Computer Simulations of the Band Structure and Density of States of the Linear Chains of NaCl Ions

Abstract

The paper presents the results of first-principles computer simulations of the band structure, the density of states, and the total energy of NaCl (NaCl, Na2Cl2, Na3Cl3, Na4Cl4, Na6Cl6) linear chains of atoms. Modelling of the specified characteristics is realised in the computer code Atomistix ToolKit combined with Virtual NanoLab. The total energy depends on the number of ions in the nanoobject under study, but practically does not depend on the geometric arrangement of ions.

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Luminescence Properties and Decay Kinetics of Mn2+ and Eu3+ Co-Dopant Ions In MgGa2O4 Ceramics

Abstract

The MgGa2O4 ceramics co-doped with Mn2+ and Eu3+ ions were synthesized via a high-temperature solid-state reaction technique. The samples with various Eu3+ concentrations were characterised using high-resolution photoluminescence (PL) spectroscopy. The PL spectra show weak matrix emission in a blue spectral region with dominant excitation band around 380 nm. Manganese ions are highly excited deeply in UV region and exhibit emission band peaked at 502 nm. The Eu3+ ions show characteristic f-f excitation and emission lines. The energy transfer between host defects and activator ions was observed. Luminescence decay curves of Mn2+ and Eu3+ emission showed complex kinetics with both Eu3+-ion concentration and excitation wavelength changes.

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Psychomotor Development After Ganciclovir Selectively Treated Congenital And Perinatal Cytomegalovirus Infection

Abstract

AIM: To study the development of children with selectively treated cytomegalovirus infection.

PATIENTS AND METHODS: We studied prospectively a risk group of 12 children with cytomegalovirus infection. These children were diagnosed by serological screening in the first three months after birth and are defined as congenital and perinatal infections. Thirteen infants with no serological evidence of previous or present cytomegalovirus infection at 4 - 12 months of age were used as controls. Ganciclovir in a dose of 10-15 mg/kg/day for at least 2 weeks followed by 5-7.5 mg/kg/day administered intravenously for at least 2 weeks more was given to 4 children from the risk group with PCR confirmed cytomegalovirus infection: to one with suspected congenital infection that presented with encephalitis, to two children with abnormal auditory evoked potentials (AEPs) and other non-neurological symptoms of a suspected congenital infection, and to one child with proven congenital infection with systemic manifestations. There was no infant with cytomegalic inclusion disease in the study. All other children in the risk group that had clinically manifested infection received isoprinosine in a dose of 50 mg/kg for one month.

RESULTS: Psychomotor development delay at age three was found in two children from the risk group and in one child in the control group. There was no difference between the two groups regarding the frequency of paroxysmal events, sensory deficiency or frequent illnesses.

CONCLUSIONS: The prognosis in cases of cytomegalovirus infection diagnosed at three years of age and treated selectively can be similar to that in infection free 3-year-old children (if there are no cases of CMV inclusion disease).

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