Atomic structure at 2.5 Å resolution of uridine phosphorylase from E. coli as refined in the monoclinic crystal lattice

AbstractUridine phosphorylase from E. coli (Upase) has been crystallized using vapor diffusion technique in a new monoclinic crystal form. The structure was determined by the molecular replacement method at 2.5 Å resolution. The coordinates of the trigonal crystal form were used as a starting model and the refinement by the program XPLOR led to the R-factor of 18.6%. The amino acid fold of the protein was found to be the same as that in the trigonal crystals. The positions of flexible regions were refined. The conclusion about the involvement in the active site is in good agreement with the results of the biochemical experiments

Tropical and subtropical cloud transitions in weather and climate prediction models: The GCSS/WGNE pacific cross-section intercomparison (GPCI)

International audienceA model evaluation approach is proposed in which weather and climate prediction models are analyzed along a Pacific Ocean cross section, from the stratocumulus regions off the coast of California, across the shallow convection dominated trade winds, to the deep convection regions of the ITCZ-the Global Energy and Water Cycle Experiment Cloud System Study/Working Group on Numerical Experimentation (GCSS/WGNE) Pacific Cross-Section Intercomparison (GPCI). The main goal of GPCI is to evaluate and help understand and improve the representation of tropical and subtropical cloud processes in weather and climate prediction models. In this paper, a detailed analysis of cloud regime transitions along the cross section from the subtropics to the tropics for the season June-July-August of 1998 is presented. This GPCI study confirms many of the typical weather and climate prediction model problems in the representation of clouds: underestimation of clouds in the stratocumulus regime by most models with the corresponding consequences in terms of shortwave radiation biases; overestimation of clouds by the 40-yrECMWFRe-Analysis (ERA-40) in the deep tropics (in particular) with the corresponding impact in the outgoing longwave radiation; large spread between the different models in terms of cloud cover, liquid water path and shortwave radiation; significant differences between the models in terms of vertical cross sections of cloud properties (in particular), vertical velocity, and relative humidity. An alternative analysis of cloud cover mean statistics is proposed where sharp gradients in cloud cover along the GPCI transect are taken into account. This analysis shows that the negative cloud bias of some models and ERA-40 in the stratocumulus regions [as compared to the first International Satellite Cloud Climatology Project (ISCCP)] is associated not only with lower values of cloud cover in these regimes, but also with a stratocumulus-to-cumulus transition that occurs too early along the trade wind Lagrangian trajectory. Histograms of cloud cover along the cross section differ significantly between models. Some models exhibit a quasi-bimodal structure with cloud cover being either very large (close to 100%) or very small, while other models show a more continuous transition. The ISCCP observations suggest that reality is in-between these two extreme examples. These different patterns reflect the diverse nature of the cloud, boundary layer, and convection parameterizations in the participating weather and climate prediction models. © 2011 American Meteorological Society

Stellarator research at IPP KIPT: status and prospects

Features of the recent Uragan-2M campaign are reviewed together with some theoretical advances. They include experiments with B4C limiter, studies of various 1…20 kHz oscillations, development of a new in-situ diagnostics for wall conditions, i.e. the thermal desorption probe, the improved numerical model of RF plasma production in stellarators in the ion cyclotron and electron-cyclotron frequency ranges, a new positive-definite form of timeharmonic Maxwell’s equations and plasma start-up studies.Розглянуто особливості недавньої кампанії Ураган-2М і деякі теоретичні результати. Вони включають у себе експерименти з B4C-лімітером, дослідження різних коливань з частотою 1…20 кГц, розробку нової insitu діагностики стану стінок (термодесорбційний зонд), поліпшену чисельну модель ВЧ-створення плазми в стелараторах в іонному циклотронному і електронному циклотронному діапазонах частот, нову позитивно визначену форму рівнянь Максвелла для однієї частоти та дослідження з високочастотного створення плазмиРассмотрены особенности недавней кампании Ураган-2М и некоторые теоретические результаты. Они включают в себя эксперименты с B4C-лимитером, исследования различных колебаний с частотой 1…20 кГц, разработку новой in-situ диагностики состояния стенок (термодесорбционный зонд), улучшенную численную модель ВЧ-создания плазмы в стеллараторах в ионном циклотроном и электронном циклотронном диапазонах частот, новую положительно определенную форму уравнений Максвелла для одной частоты и исследования по высокочастотному созданию плазмы

The DUNE far detector vertical drift technology. Technical design report

DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

История политических и гражданских прав женщин в Норвегии

The formation and development of women's rights in Europe has a long history, different within each of the states. The publication is devoted to the study of the political and civil rights of women in Norway from the beginning of the 19th to the end of the 20th centuries. The authors consider the development of women's rights against the backdrop of a changing situation within the state. The key milestones in establishing the political and civil rights of women are analysed.Становление и развитие прав женщин в Европе имеет длительную историю, различную внутри каждого из государств. Публикация посвящена изучению политических и гражданских прав женщин в Норвегии в период с начала XIX до конца XX века. Авторы рассматривают развитие прав женщин на фоне меняющейся обстановки внутри государства. Анализируются ключевые вехи в установлении политических и гражданских прав женщин

New derivatives of bacteriopurpurin with thiolated au (I) complexes: Dual dark-and light activated antitumor potency

Background: Conventional antitumor Photosensitizers (PS) are normally low toxic in the dark whereas light activation triggers massive cell death (photodynamic therapy, PDT). Objective: To expand the therapeutic potential of PS to dual potency cytocidal agents, taking advantage of the use of bacteriopurpurin for a deeper tissue penetration of light, and suitability of the tetrapyrrolic macrocycle for chemical modifications at its periphery. Methods: Conjugation of a pro-oxidant thiolate Au (I) moiety to the bacteriopurpurin core and evaluation of cytotoxicity in cell culture and in vivo. Results: New water-soluble derivatives showed micromolar cytotoxicity for cultured human tumor cell lines in the dark, including the subline with an altered drug response due to p53 inactivation. Cellular PDT with the selected conjugate, thiolate Au (I)-dipropoxybacteriopurpurinimide (compound 6) with two triphenylphosphine Au fragments, triggered rapid (within minutes) cell death. Damage to the plasma membrane (necrosis) was a hallmark of cell death by compound 6 both in the dark and upon light activation. Furthermore, one single i.v. injection of compound 6 caused retardation of transplanted syngeneic tumors at the tolerable dose. Illumination of tumors that accumulated compound 6 significantly synergized with the effect of 6 in the dark. Conclusion: Complexes of virtually non-toxic, photoactivatable bacteriopurpurin with the gold-containing organic moiety are considered the dual potency antitumor agents, tentatively applicable for intractable tumors. © 2020 Bentham Science Publishers