Anisotropic Magnetoconductance in Quench-Condensed Ultrathin Beryllium Films

Near the superconductor-insulator (S-I) transition, quench-condensed ultrathin Be films show a large magnetoconductance which is highly anisotropic in the direction of the applied field. Film conductance can drop as much as seven orders of magnitude in a weak perpendicular field (< 1 T), but is insensitive to a parallel field in the same field range. We believe that this negative magnetoconductance is due to the field de-phasing of the superconducting pair wavefunction. This idea enables us to extract the finite superconducting phase coherence length in nearly superconducting films. Our data indicate that this local phase coherence persists even in highly insulating films in the vicinity of the S-I transition.Comment: 4 pages, 4 figure RevTex, Typos Correcte

MULTILAYER Mg/NbO NANOSTRUCTURES

Multilayer (Mg/NbO)82 nanostructure has been obtained by ion-beam sputtering of two targets and subsequent deposition on the rotating substrate. Thickness of each layer in the obtained structure as well as resistivity dependence on the bilayer thickness have been measured.Работа выполнена при финансовой поддержке РФФИ (проект 15-02-05920)

Роль детей и взрослых как резервуара возбудителей в период сезонного подъема заболеваемости инфекциями верхних дыхательных путей

Infection caused by the Epstein-Barr virus (EBV) is more common in children and is transmitted through contact with saliva. The role of adults in the epidemic process has not been sufficiently studied.The goal is to study the role of children and adults with catarrhal phenomena in the spread of EBV during the seasonal epidemic rise in the incidence of upper respiratory tract infections (URTI).Materials and methods. In the epidemic season of 201 9—2020, 226 people with catarrhal symptoms (140 adults and 86 children) were examined by PCR for the presence of EBV and other URTI pathogens in their nasal and oropharyngeal smears.Results. Significant differences in the frequency of detection of pathogens in children and adults have not been established. In both groups, EBV was detected as a single pathogen and in combination with other pathogens. The presence of a runny nose, sneezing and coughing is unusual for EBV, but occurs when EBV is combined with other URTI pathogens.Discussion. The presence of EBV in the nasopharynx and oropharynx in children and adults plays an important role in the spread of the pathogen. The combination of EBV with other pathogens that cause runny nose, sneezing, and coughing contributes to the formation of a more concentrated infectious aerosol and its spread over long distances.Conclusions. During the seasonal epidemic upsurge, children and adults are equally involved in URTI epidemic process and are sources of EBV infection with a frequency of 3 1.39 and 37.14 per 1 00 examined and an average concentration of the virus in smears of 31 199 and 33 074 copies/ ml, respectively. In children and adults, EBV was detected in combination with other U RTI pathogens with a frequency of 1 6.28 and 1 8.57 per 1 00 subjects, respectively. The presence of EBV in the upper respiratory tract, together with other pathogens, contributes to the active transmission of EBV during the seasonal epidemic rise of upper respiratory tract infections.Инфекция, вызванная вирусом Эпштейна-Барр (ВЭБ), чаще встречается у детей и передается при контакте со слюной. Роль взрослых в эпидемическом процессе изучена недостаточно.Цель — изучить роль детей и взрослых с катаральными явлениями в распространении ВЭБ в период сезонного эпидемического подъема заболеваемости инфекциями верхних дыхательных путей (ИВДП).Материалы и методы. В эпидемический сезон 2019—2020 гг. методом ПЦР на наличие ВЭБ и других возбудителей ИВДП в мазках их носо- и ротоглотки обследовано 226 человек с катаральными явлениями (140 взрослых и 86 детей).Результаты. Достоверные различия в частоте обнаружения возбудителей у детей и взрослых не установлены. В этих группах ВЭБ выявлялся как единственный возбудитель и в сочетании с другими патогенами. Наличие насморка, чихания и кашля для ВЭБ нехарактерно, но имеет место при сочетании ВЭБ с другими возбудителями ИВДП.Обсуждение. Присутствие ВЭБ в носо- и ротоглотке у детей и взрослых играет важную роль в распространении возбудителя. Сочетание ВЭБ с другими возбудителями, вызывающими насморк, чихание, кашель, способствует формированию более концентрированного инфекционного аэрозоля и распространению его на большие расстояния.Выводы. В период сезонного эпидемического подъема дети и взрослые в равной степени вовлекаются в эпидемический процесс ИВДП и являются источниками ВЭБ-инфекции с частотой 31,39 и 37,14 на 100 обследованных и средней концентрацией вируса в мазках 31 199 и 33 074 копий/мл соответственно. У детей и взрослых ВЭБ выявлялся в сочетании с другими возбудителями ИВДП с частотой 16,28 и 1 8,57 на 100 обследованных соответственно. Присутствие ВЭБ в верхних дыхательных путях совместно с другими патогенами способствует активной передаче ВЭБ в период сезонного эпидемического подъема ИВДП

Treatment and disease progression in a birth cohort of vertically HIV-1 infected children in Ukraine

Background: Ukraine has the highest HIV prevalence (1.6%) and is facing the fastest growing epidemic in Europe. Our objective was to describe the clinical, immunological and virological characteristics, treatment and response in vertically HIV-infected children living in Ukraine and followed from birth.Methods: The European Collaborative Study (ECS) is an ongoing cohort study, in which HIV-1 infected pregnant women are enrolled and followed in pregnancy, and their children prospectively followed from birth. ECS enrolment in Ukraine started in 2000 initially with three sites, increasing to seven sites by 2009.Results: A total of 245 infected children were included in the cohort by April 2009, with a median age of 23 months at most recent follow-up; 33% (n = 77) had injecting drug using mothers and 85% (n = 209) were infected despite some use of antiretroviral prophylaxis for prevention of mother-to-child transmission. Fifty-five (22%) children had developed AIDS, at a median age of 10 months (IQR = 6-19). The most prevalent AIDS indicator disease was Pneumocystis jiroveci pneumonia (PCP). Twenty-seven (11%) children had died (median age, 6.2 months). Overall, 108 (44%) children had started highly active antiretroviral treatment (HAART), at a median 18 months of age; median HAART duration was 6.6 months to date. No child discontinued HAART and 92% (100/108) remained on their first-line HAART regimen to date. Among children with moderate/severe immunosuppression, 36% had not yet started HAART. Among children on HAART, 71% (69/97) had no evidence of immunosuppression at their most recent visit; the median reduction in HIV RNA was 4.69 log10 copies/mL over a median of 10 months treatment. From survival analysis, an estimated 94%, 84% and 81% of children will be alive and AIDS-free at 6, 12 and 18 months of age, respectively. However, survival increased significantly over time: estimated survival rates to 12 months of age were 87% for children born in 2000/03 versus 96% for those born in 2004/08.Conclusion: One in five children had AIDS and one in ten had died. The half of children who received HAART has responded well and survival has significantly improved over time. Earlier diagnosis and prompt initiation of HAART remain key challenges