Journal articles: 'U2U'

1

Chen, Xu. "A Time-Oscillating Hartree-Type Schrödinger Equation." Abstract and Applied Analysis 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/950132.

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We consider the time-oscillating Hartree-type Schrödinger equationiut+Δu+θωtx-γ*u2u=0, whereθis a periodic function. For the mean valueI(θ)ofθ, we show that the solutionuωconverges to the solution ofiUt+ΔU+Iθx-γ*U2U=0for their local well-posedness and global well-posedness.

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Romann, Michael, Marie Javet, Stephen Cobley, and Dennis-Peter Born. "How Relative Age Effects Associate with Football Players’ Market Values: Indicators of Losing Talent and Wasting Money." Sports 9, no. 7 (July 9, 2021): 99. http://dx.doi.org/10.3390/sports9070099.

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Background: In football, annual age-group categorization leads to relative age effects (RAEs) in talent development. Given such trends, relative age may also associate with market values. This study analyzed the relationship between RAEs and market values of youth players. Methods: Age category, birthdate, and market values of 11,738 youth male football players were obtained from the “transfermarkt.de” database, which delivers a good proxy for real market values. RAEs were calculated using odds ratios (OR) with 95% confidence intervals (95%CI). Results: Significant RAEs were found across all age-groups (p < 0.05). The largest RAEs occurred in U18 players (Q1 [relatively older] v Q4 [relatively younger] OR = 3.1) ORs decreased with age category, i.e., U19 (2.7), U20 (2.6), U21 (2.4), U22 (2.2), and U23 (1.8). At U19s, Q1 players were associated with significantly higher market values than Q4 players. However, by U21, U22, and U23 RAEs were inversed, with correspondingly higher market values for Q4 players apparent. While large typical RAEs for all playing positions was observed in younger age categories (U18–U20), inversed RAEs were only evident for defenders (small-medium) and for strikers (medium-large) in U21–U23 (not goalkeepers and midfielders). Conclusions: Assuming an equal distribution of football talent exists across annual cohorts, results indicate the selection and market value of young professional players is dynamic. Findings suggest a potential biased selection, and undervaluing of Q4 players in younger age groups, as their representation and market value increased over time. By contrast, the changing representations and market values of Q1 players suggest initial overvaluing in performance and monetary terms. Therefore, this inefficient talent selection and the accompanying waste of money should be improved.

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Biehl, Larry L., Lan Zhao, Carol X. Song, and Christopher G. Panza. "Cyberinfrastructure for the collaborative development of U2U decision support tools." Climate Risk Management 15 (2017): 90–108. http://dx.doi.org/10.1016/j.crm.2016.10.003.

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Zhao, Deming, and Jian Wu. "Contribution of Urban Surface Expansion to Regional Warming in Beijing, China." Journal of Applied Meteorology and Climatology 56, no. 6 (June 2017): 1551–59. http://dx.doi.org/10.1175/jamc-d-17-0019.1.

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AbstractThe contribution of urban surface expansion to regional warming as detected from meteorological observational station data may vary with considerable uncertainty because of the spatial heterogeneity of such data—a situation that promotes a requirement for numerical model-based investigations. Satellite-based images from 1980 to 2016 that have fine resolution over three city clusters and that display the urban surface expansion in China from rapid economic development and anthropogenic activity were used to perform 37-yr nested dynamical downscaling using the Weather Research and Forecasting (WRF) Model. The urban surface areas in Beijing, China, expressed marked expansion in the last 37 years. The contribution of urban surface expansion to regional warming was approximately 22% of the overall warming in Beijing and was stronger in the plains areas of Beijing (42%). The contributions to land-use grids that changed from nonurban (in 1980) to urban (in 2016; N2U) were much stronger than those to grids that were classified as urban in both time periods (U2U), which were closer to the values of urban areas (including N2U and U2U) because of the intense increase in urban surface areas. Urban-related warming expressed marked annual variation and was greater in the warm seasons and smaller in the cold seasons. The greater increase in surface air temperature (SAT) minimum and the weaker SAT maximum accounted for the decreased diurnal temperature range.

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Juarez Campos, B., Elena Kaikina, and Hector F. Ruiz Paredes. "Mixed Initial-Boundary Value Problem for the Capillary Wave Equation." Advances in Mathematical Physics 2016 (2016): 1–21. http://dx.doi.org/10.1155/2016/7475061.

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We study the mixed initial-boundary value problem for the capillary wave equation:iut+u2u=∂x3/2u, t>0, x>0; u(x,0)=u0(x), x>0; u(0,t)+βux(0,t)=h(t), t>0, where∂x3/2u=(1/2π)∫0∞sign⁡x-y/x-yuyy(y) dy. We prove the global in-time existence of solutions of IBV problem for nonlinear capillary equation with inhomogeneous Robin boundary conditions. Also we are interested in the study of the asymptotic behavior of solutions.

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Bachellerie, Jean-Pierre, Monique Nicoloso, Liang-Hu Qu, Bernard Michot, Michèle Caizergues-Ferrer, Jérome Cavaille, and Marie-Hélène Renalier. "Novel intron-encoded small nucleolar RNAs with long sequence complementarities to mature rRNAs involved in ribosome biogenesis." Biochemistry and Cell Biology 73, no. 11-12 (December 1, 1995): 835–43. http://dx.doi.org/10.1139/o95-091.

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Recently, several new snoRNAs encoded in introns of genes coding for ribosomal, ribosome-associated, or nucleolar proteins have been discovered. We are presently studying four of these intronic snoRNAs. Three of them, U20, U21, and U24, are closely related to each other on a structural basis. They are included in genes encoding nucleolin and ribosomal proteins L5 and L7a, respectively, in warm-blooded vertebrates. These three metabolically stable snoRNAs interact with nucleolar protein fibrillarin. In addition, they display common features that make them strikingly related to snoRNA U14. U14 contains two tracts of complementarity to 18S rRNA, which are required for the production of 18S rRNA. U20 displays a 21 nucleotide (nt) long complementarity to 18S rRNA. U21 contains a 13 nt complementarity to an invariant sequence in eukaryotic 28S rRNA. U24 has two separate 12 nt long complementarities to a highly conserved tract of 28S rRNA. Phylogenetic evidences support the fundamental importance of the pairings of these three snoRNAs to pre-rRNA, which could be involved in a control of pre-rRNA folding during preribosome assembly. By transfection of mouse cells, we have also analyzed the processing of U20 and found that the -cis acting signals for its processing from intronic RNA are restricted to the mature snoRNA sequence. Finally, we have documented changes of host genes for these three intronic snoRNAs during the evolution of eukaryotes.Key words: snoRNA, pre-rRNA, folding, genes, introns.

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Angel, James R., Melissa Widhalm, Dennis Todey, Ray Massey, and Larry Biehl. "The U2U Corn Growing Degree Day tool: Tracking corn growth across the US Corn Belt." Climate Risk Management 15 (2017): 73–81. http://dx.doi.org/10.1016/j.crm.2016.10.002.

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8

Kambach, C., and I. W. Mattaj. "Nuclear transport of the U2 snRNP-specific U2B'' protein is mediated by both direct and indirect signalling mechanisms." Journal of Cell Science 107, no. 7 (July 1, 1994): 1807–16. http://dx.doi.org/10.1242/jcs.107.7.1807.

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Experiments investigating the nuclear import of the U2 snRNP-specific B'' protein (U2B'') are presented. U2B'' nuclear transport is shown to be able to occur independently of binding to U2 snRNA. The central segment of the protein (amino acids 90–146) encodes an unusual nuclear localization signal (NLS) that is related to that of the U1 snRNP-specific A protein. However, nuclear import of U2B'' does not depend on this NLS. Sequences in the N-terminal RNP motif of the protein are sufficient to direct nuclear transport, and evidence is presented that the interaction of U2B'' with the U2A' protein mediates this effect. This suggests that U2B'' can ‘piggy-back’ to the nucleus in association with U2A’, and thus be imported to the nucleus by two different mechanisms. U2A' nuclear transport, on the other hand, can occur independently of both U2B'' binding and of U2 snRNA.

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9

Ribeiro, Laura Michaella Batista, Ivan Müller, and Leandro Buss Becker. "Communication Interface Manager for Improving Performance of Heterogeneous UAV Networks." Sensors 21, no. 13 (June 22, 2021): 4255. http://dx.doi.org/10.3390/s21134255.

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Exchanging messages with stable connections in missions composed of multiple unmanned aerial vehicles (UAV) remains a challenge. The variations in UAV distances from each other, considering their individual trajectories, and the medium dynamic factors are important points to be addressed.In this context, to increase the stability of UAV-to-UAV (U2U) communication with link quality, this paper presents an interface manager (IM) that is capable of improving communication in multi-UAV networks.Given a predefined set of available individual wireless interfaces, the proposed IM dynamically defines the best interface for sending messages based on on-flight conditions sensed and calculated dynamically from the wireless medium. Different simulation scenarios are generated using a complex and realistic experimental setup composed of traditional simulators such as NS-3, Gazebo, and GzUAV. IEEE 802.11n 2.4 GHz and 802.11p 5 GHz interfaces are used for the IM selection. The IM performance is evaluated in terms of metrics from the medium-access-control (MAC) and physical layers, which aim to improve and maintain the connectivity between the UAVs during the mission, and from the application layer, which targets the reliability in the delivery of messages. The obtained results show that compared with the cases where a single interface is used, the proposed IM is able to increase the network throughput and presents the best proportion of transmitted and received packets, reception power (−60 dBm to −75 dBm), and loss (−80 dB to −85 dB), resulting in a more efficient and stable network connections.

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10

Zhao, Deming, and Jian Wu. "Modelling Daily Mean Surface Air Temperature Calculated from Different Methods and Its Impact on Urban-Related Warming Evaluations over Guangzhou and Shenzhen Using the WRF Model." Atmosphere 10, no. 2 (January 27, 2019): 48. http://dx.doi.org/10.3390/atmos10020048.

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The impacts of urban surface expansion, based on satellite-derived data displaying urban surface expansion in China at different spatial scales from 1980 to 2016, were investigated using nested dynamical downscaling methods with the Weather Research and Forecasting (WRF) regional climate model at a 3.3-km resolution over a city and city cluster scale. Urban-related warming, based on daily mean surface air temperature at 2 m (SAT), calculated from the averages of four time records each day (00, 06, 12, and 18 h UTC, T4) and averages of SAT maximum (Tmax) and minimum (Tmin) (Txn), was evaluated. Differences in urban-related warming contributions calculated using T4 and Txn were small, whereas annual mean SAT and trends calculated using Txn were respectively and significantly larger and smaller than those calculated using T4 over Guangzhou and Shenzhen, excluding the trends over middle-northern Shenzhen. The differences in annual mean SAT calculated using T4 and Txn are attributed to nonlinear or asymmetric variations with time for the diurnal cycle of SAT. Meanwhile, differences in trends between T4 and Txn are interpreted as a strong trend for Tmin and a weak one for Tmax, which mitigated the trend for Txn. The impacts on the evaluations of urban-related warming contributions calculated from different methods were the largest over the areas classified as urban surfaces in both time periods (U2U), especially during intense urban-surface-expansion periods between 2000 and 2016. The subregional performances in the changes in annual mean SAT, trends, and urban-related warming are attributed to urban-surface-expansion, which induced varied changes in the diurnal cycle due to asymmetric warming during the daytime and nighttime over different subregions.

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Song, Shiying, and Yujun Cui. "Multiplicity Solutions for Integral Boundary Value Problem of Fractional Differential Systems." Discrete Dynamics in Nature and Society 2020 (March 12, 2020): 1–10. http://dx.doi.org/10.1155/2020/2651845.

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This paper deals with the existence and multiplicity of solutions for the integral boundary value problem of fractional differential systems: D0+α1u1t=f1t,u1t,u2t,D0+α2u2t=f2t,u1t,u2t,u10=0, D0+β1u10=0, D0+γ1u11=∫01D0+γ1u1ηdA1η,u20=0, D0+β2u20=0, D0+γ2u21=∫01D0+γ2u2ηdA2η,, where fi:0,1×0,∞×0,∞⟶0,∞ is continuous and αi−2<βi≤2,αi−γi≥1,2<αi≤3,γi≥1i=1,2.D0+α is the standard Riemann–Liouville’s fractional derivative of order α. Our result is based on an extension of the Krasnosel’skiĭ’s fixed-point theorem due to Radu Precup and Jorge Rodriguez-Lopez in 2019. The main results are explained by the help of an example in the end of the article.

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Williams, Sandra G., and Kathleen B. Hall. "Binding Affinity and Cooperativity Control U2B″/snRNA/U2A′ RNP Formation." Biochemistry 53, no. 23 (June 5, 2014): 3727–37. http://dx.doi.org/10.1021/bi500438e.

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13

Preußer, Christian, Zsofia Palfi, and Albrecht Bindereif. "Special Sm Core Complex Functions in Assembly of the U2 Small Nuclear Ribonucleoprotein of Trypanosoma brucei." Eukaryotic Cell 8, no. 8 (June 19, 2009): 1228–34. http://dx.doi.org/10.1128/ec.00090-09.

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ABSTRACT The processing of polycistronic pre-mRNAs in trypanosomes requires the spliceosomal small ribonucleoprotein complexes (snRNPs) U1, U2, U4/U6, U5, and SL, each of which contains a core of seven Sm proteins. Recently we reported the first evidence for a core variation in spliceosomal snRNPs; specifically, in the trypanosome U2 snRNP, two of the canonical Sm proteins, SmB and SmD3, are replaced by two U2-specific Sm proteins, Sm15K and Sm16.5K. Here we identify the U2-specific, nuclear-localized U2B″ protein from Trypanosoma brucei. U2B″ interacts with a second U2 snRNP protein, U2-40K (U2A′), which in turn contacts the U2-specific Sm16.5K/15K subcomplex. Together they form a high-affinity, U2-specific binding complex. This trypanosome-specific assembly differs from the mammalian system and provides a functional role for the Sm core variation found in the trypanosomal U2 snRNP.

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Caspary, Friederike, and Bertrand Séraphin. "The yeast U2A′/U2B″ complex is required for pre-spliceosome formation." EMBO Journal 17, no. 21 (November 2, 1998): 6348–58. http://dx.doi.org/10.1093/emboj/17.21.6348.

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15

Iizuka, Jun, Teruyuki Kitabayashi, Yuki Minagawa, and Masaki Yasuè. "Parametrization of Pontecorvo–Maki–Nakagawa–Sakata mixing matrix based on CP-violating bipair neutrino mixing." Modern Physics Letters A 30, no. 05 (February 3, 2015): 1550019. http://dx.doi.org/10.1142/s0217732315500194.

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CP violation in neutrino interactions is described by three phases contained in Pontecorvo–Maki–Nakagawa–Sakata mixing matrix (U PMNS ). We argue that the phenomenologically consistent result of the Dirac CP violation can be obtained if U PMNS is constructed along bipair neutrino mixing scheme, namely, requiring that |U12| = |U32| and |U22| = |U23| (case 1) and |U12| = |U22| and |U32| = |U33| (case 2), where Uij stands for the i × j matrix element of U PMNS . As a result, the solar, atmospheric and reactor neutrino mixing angles θ12, θ23 and θ13, respectively, are correlated to satisfy cos 2θ12 = sin 2 θ23 - tan 2 θ13 (case 1) or cos 2θ12 = cos 2 θ23 - tan 2 θ13 (case 2). Furthermore, if Dirac CP violation is observed to be maximal, θ23 is determined by θ13 to be: [Formula: see text] (case 1) or [Formula: see text] (case 2). For the case of non-maximal Dirac CP violation, we perform numerical computation to show relations between the CP-violating Dirac phase and the mixing angles.

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Jasirwan, Chyntia, Huamin Tang, Akiko Kawabata, and Yasuko Mori. "The human herpesvirus 6 U21-U24 gene cluster is dispensable for virus growth." Microbiology and Immunology 59, no. 1 (January 2015): 48–53. http://dx.doi.org/10.1111/1348-0421.12208.

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Cao, Huaihuo. "Global Solutions in the Species Competitive Chemotaxis System with Inequal Diffusion Rates." Discrete Dynamics in Nature and Society 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/5015246.

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This paper is devoted to studying the two-species competitive chemotaxis system with signal-dependent chemotactic sensitivities and inequal diffusion rates u1t=Δu1-∇·u1χ1v∇v+μ1u11-u1-a1u2, x∈Ω, t>0, u2t=Δu2-∇·u2χ2v∇v+μ2u21-a2u1-u2, x∈Ω, t>0, vt=τΔv-γv+u1+u2, x∈Ω, t>0, under homogeneous Neumann boundary conditions in a bounded and regular domain Ω⊂Rn (n≥1). If the nonnegative initial date (u10,u20,v0)∈(C1(Ω¯))3 and v0∈(v_,v¯) where the constants v¯>v_≥0, the system possesses a unique global solution that is uniformly bounded under some suitable assumptions on the chemotaxis sensitivity functions χ1(v), χ2(v) and linear chemical production function -γv+u1+u2.

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Rubajczyk, Krystian, and Andrzej Rokita. "The Relative Age Effect in Poland's Elite Youth Soccer Players." Journal of Human Kinetics 64, no. 1 (October 15, 2018): 265–73. http://dx.doi.org/10.1515/hukin-2017-0200.

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Abstract The relative age effect (RAE) is related to discrimination against youth athletes born in the last quarter of the calendar year. The current study presents research on the RAE in elite youth soccer players in Poland. Players in the Central Junior League (CLJ) finals represent 0.59% of the 25,756 players under 20 years old (U20). This study analyzed the post-game protocols of the CLJ knockout stage from the 2013/2014 and 2014/2015 seasons as well as the U17-U21 teams during 2015, including only players who played on the field for at least one minute (n = 395). The results revealed the existence of RAE in the examined groups ( CLJ 2013/2014, χ23 = 15.441, p < 0.01, CLJ 2014/2015, χ23 = 20.891, p < 0.001 U17-U21, χ23 = 25.110, p < 0.001). In addition, the results differed by monthly birth distribution in the Polish population (PP) between 1995 and 1999. This study is the first to examine the RAE in youth soccer in Poland. The occurrence of the RAE with regard to the most promising youth and national team players suggests that a similar effect exists among younger age categories. To reduce the RAE related to identifying soccer talent, tools should be implemented to optimize the player-selection process, such as those that consider the biological development of a player.

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Nagengast, A. A. "The Drosophila U2 snRNP protein U2A' has an essential function that is SNF/U2B'' independent." Nucleic Acids Research 29, no. 18 (September 15, 2001): 3841–47. http://dx.doi.org/10.1093/nar/29.18.3841.

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MIYAZAKI, TAKESHI, and JULIAN C. R. HUNT. "Linear and nonlinear interactions between a columnar vortex and external turbulence." Journal of Fluid Mechanics 402 (January 10, 2000): 349–78. http://dx.doi.org/10.1017/s0022112099006990.

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The structure of initially isotropic homogeneous turbulence interacting with a columnar vortex (with circulation Γ and radius σ), idealized both as a solid cylinder and a hollow core model is analysed using the inhomogeneous form of linear rapid distortion theory (RDT), for flows where the r.m.s. turbulence velocity u0 is small compared with Γ/σ. The turbulent eddies with scale Γ are distorted by the mean velocity gradient and also, over a distance Γ from the surface of the vortex, by their direct impingement onto it, whether it is solid or hollow. The distortion of the azimuthal component of turbulent vorticity by the differential rotation in the mean flow around the columnar vortex causes the mean-square radial velocity away from the cylinder to increase as (Γt/2πr2)2 (Γx/r)u20, when (r − σ) > Γx, but on the surface of the vortices ((r − σ) < Γx) where 〈u2r〉 is reduced, 〈u2z〉 increases to the same order, while the other components do not grow. Statistically, while the vorticity field remains asymmetric, the velocity field of small-scale eddies near the vortex core rapidly becomes axisymmetric, within a period of two or three revolutions of the columnar vortex. Calculation of the distortion of small-scale initially random velocity fields shows how the turbulent eddies, as they are wrapped around the columnar vortex, become like vortex rings, with similar properties to those computed by Melander & Hussain (1993) using a fully nonlinear direct numerical simulation. A mechanism is proposed for how interactions between the external turbulence and the columnar vortex can lead to non-axisymmetric vortex waves being excited on the vortex and damped fluctuations in its interior. If the columnar vortex is not significantly distorted by these linear effects, estimates are made of how nonlinear effects lead to the formation of axisymmetric turbulent vortices which move as result of their image vorticity (in addition to the self-induction velocity) at a velocity of order u0tΓ/σ2 parallel to the vortex. Even when the circulation (γ) of the turbulent vortices is a small fraction of Γ, they can excite self-destructive displacements through resonance on a time scale σ/u0.

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Jafar, A. S., I. S. El-Ageli, and H. H. Al-Attar. "Discussion and Comparison of Horizontal-Well Performance in Bouri Field." SPE Reservoir Evaluation & Engineering 3, no. 06 (December 1, 2000): 567–72. http://dx.doi.org/10.2118/68321-pa.

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Summary Seven horizontal wells were drilled in Bouri field, offshore Libya, and put on production between 1989 and 1992. This paper presents the experience gained in producing and monitoring these wells over the past few years. Comparison of well basic characteristics and performances with offset conventional wells indicates their higher productivity and general superior performance. Different monitoring activities conducted on these wells are discussed, including transient test analyses and production logs. Free gas production was found to be related to the combined phenomena of coning and fracture flow mechanism. These discussions show that, in most of the cases, production of water and gas is inevitable as long as economic oil rates are to be maintained. The targets set for these wells in terms of recovery increase and production troubles reduction were at least partially fulfilled. Introduction Bouri field is an elongated E-W-orientated anticline located in the Libyan offshore about 130 km NW of Tripoli. The field was discovered in the 1970s and started on production in 1988, from the eastern two sectors (3 and 4). The pay interval is the uppermost member of the Metlaoui formation from the Early Eocene age, at an average depth of 8,000 ft subsea level, with a lithology dominated by Nummulitic limestones. The reservoir comprises a thick oil ring of around 300 ft overlaid by an extended primary gas cap and underlain by water. The resultant drive mechanism is a combination of aquifer activity and gas-cap expansion. Different fault sets cut the structure with varied local intensity, affecting more dominantly the southern flank, where water advance is mostly appreciated. These faults and their associated network of fractures and microfractures affect the characteristics of the rocks and influence, to one degree or another, the productivity and the flow dynamics in the reservoir. Horizontal Wells Of the 55 wells drilled for field development, seven were drilled as horizontals (HWS). The other wells are conventionals (CWS), comprising slanted wells with up to 65°, and two verticals. The original objective was to efficiently drain the reservoir oil below the gas cap (Fig. 1). Optimizing the production rates while keeping low drawdowns should help to minimize the gas coning tendency. Geological Brief. The particular target of all horizontal drilling in the field was the stratigraphic layer of Metlaoui formation designated as U2. The layer forms the lowermost interval of the pay zone (Fig. 2) and is further divided into three subunits (from bottom to top), U2a, U2b, and U2c. The first subunit represents a zone of good petrophysical properties with an average thickness that exceeds 80 ft in the interested area. Besides having excellent lateral homogeneity, it also contains some 20% of the original oil in place (OOIP) in the developed area. It was the target of most of the HWS in Sector 4. The unit gradually diminishes toward the west, and disappears completely in the Sector 3 area. The intermediate subunit U2b is composed mainly of cemented Nummulitic limestone that forms a compact 20- to 30-ft well traceable layer extending all the way above U2a. It represents a presumed natural barrier to gas expansion, further promoting U2a as a favorable position for the HWS. The upper subunit U2c has a much wider areal extension than the lower two, covering the total developed area with an average thickness of 80 ft and with fairly good properties. It was the target of the two horizontal wells in Sector 3 and one in Sector 4. Relevant well information is found in Table 1. On the other hand, a thick zone of poor-porosity rocks that lies directly below layer U2 was envisaged to hamper the water advancement. The first five horizontals, all in Sector 4, were actually located below the gas cap. The other two were drilled in a part of the field with highly complicated structural setting owing to extensive faulting (Sector 3), thus hitting the pay zone at the edge of the gas cap, as seen in Fig. 1. Completion and Stimulation. The main objectives of completing and stimulating the HWS in the field were to remove the formation damage and to obtain the maximum contributing length along the completed interval. Early experience in the field had highlighted the necessity of acid treatment to start production, as the Nummulitic porosity was being badly damaged by drilling operations. Following the poor experience of the stimulation and the consequent flow profile in the first horizontal (B4-09H), several variations in completion design and stimulation techniques were attempted. Feedback from transient testing and production logging results helped to optimize the implemented specific acid volume as 1 bbl/ft. Spotting acid by coiled tubing with movement along the perforated interval was found very effective. The use of external inflatable casing packers (EICP) with selective stimulation of intervals1 was an extra aid. A summary of data is shown in Table 2, together with the resultant perforation efficiency (PE) defined as the ratio of the contributing to total completed interval. Acid treatments successfully stimulated the HWS to skin factors of -4 (Tables 3 and 4), recalling that the wells were not able to flow initially. Monitoring Activities. Routine Flow Testing and Production Allocation. Flow tests were run on the basis of one test per month with a two-phase separator. In this way, accurate production allocation is allowed by means of continuous updating of deliverability curves, in addition to close observation of any change in well performance caused by free gas or water flow. Produced water shows the tendency to form a strong emulsion with oil. Because of the method of sampling for water-cut determination, oil rate is usually underestimated. Production results in high-water-cut wells are considered less reliable. Static Pressure. Initial static pressure for each well was measured through stabilized buildups. The low frequency of static pressure records on horizontal wells is caused by the long shut-in times required for stabilization, with the corresponding loss of production. Nevertheless, some 26 pressure surveys were run on those wells in total. The magnitude and the trend of decline in pressure (Fig. 3) reflect the reservoir pressure behavior in the field.

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Price, Stephen R., Philip R. Evans, and Kiyoshi Nagai. "Crystal structure of the spliceosomal U2B″–U2A′ protein complex bound to a fragment of U2 small nuclear RNA." Nature 394, no. 6694 (August 1998): 645–50. http://dx.doi.org/10.1038/29234.

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Fei, Weihong, and George A. McMechan. "“CRP-based seismic migration velocity analysis,” Weihong Fei and George A. McMechan, GEOPHYSICS, 71, no. 3, U21–U28." GEOPHYSICS 72, no. 6 (November 2007): Y7. http://dx.doi.org/10.1190/gpysa7.72.y7_2.

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Kriaa, Mouna, Hanen Boukedi, Marwa Ben Rhouma, Yosri Ben Nasr, Slim Tounsi, Lotfi Mellouli, and Radhouane Kammoun. "Overproduction of Glucose Oxidase by Aspergillus tubingensis CTM 507 Randomly Obtained Mutants and Study of Its Insecticidal Activity against Ephestia kuehniella." BioMed Research International 2020 (June 6, 2020): 1–8. http://dx.doi.org/10.1155/2020/9716581.

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In order to enhance the production of glucose oxidase (GOD), random mutagenesis of Aspergillus tubingensis CTM 507 was performed using the chemical and physical mutagens: nitric acid and UV irradiation, respectively. The majority of the isolated mutants showed good GOD production, but only some mutants presented a significant overproduction, as compared with the parent strain. The selected mutants (19 strains), showing an overproduction larger than 200%, are quite stable after three successive subcultures. Among these, six strains revealed an important improvement in submerged fermentation. The insecticidal activity of GOD produced by the wild and the selected mutant strains was evaluated against the third larval instars of E. kuehniella. Mutant strains U11, U12, U20, and U21, presenting the most important effect, displayed an LC50 value of 89.00, 88.51, 80.00, and 86.00 U/cm2, respectively, which was 1.5-fold more important than the wild strain (61 U/cm2). According to histopathology observations, the GOD enzyme showed approximately similar damage on the E. kuehniella midgut including rupture and disintegration of the epithelial layer and cellular vacuolization. The data supports, for the first time, the use of GOD as a pest control agent against E. kuehniella.

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Boelens, Wilbert, Daniel Scherly, Ria P. Beijer, Eric J. R. Jansen, Nina A. Dathan, lain W. Mattaj, and Walther J. van Venrooij. "A weak interaction between the U2A′ protein and U2 snRNA helps to stabilize their complex with the U2B” protein." Nucleic Acids Research 19, no. 3 (1991): 455–60. http://dx.doi.org/10.1093/nar/19.3.455.

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Peixoto, Joicy V. M., Ana L. A. Ribeiro, Gabriel M. Maciel, Camila S. de Oliveira, Rafael R. Finzi, and Emmerson R. de Moraes. "Productivity, acylsugar concentrations and resistance to the two-spotted spider mite in genotypes of salad tomatoes." Revista Brasileira de Engenharia Agrícola e Ambiental 24, no. 9 (September 2020): 596–602. http://dx.doi.org/10.1590/1807-1929/agriambi.v24n9p596-602.

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ABSTRACT The objective of this study was to characterize genotypes of the salad-type tomato with a determinate growth habit and select genotypes resistant to the two-spotted spider mite for higher productivity and fruit quality. The experiment was conducted at the Horticultural Experimental Station (18°42’43.19” S and 47°29’55.8” W, 873 m altitude) of the Universidade Federal de Uberlândia (UFU), Monte Carmelo campus, from January to June 2018. The experimental design was in randomized blocks containing 16 treatments [12 populations of the F3RC2 generation and four controls: two commercial cultivars (Santa Clara and Rio Grande), the recurrent parent (UFU-057) and the wild species Solanum pennellii (LA-716)] with three repetitions. The accessions UFU-057F3RC210#3.6.1 and UFU-057F3RC213#2.1.2 have high potential for genetic improvement regarding resistance to the two-spotted spider mite. The genotypes UFU-13#4.4.1, UFU-7#4.7.1, UFU-7#4.3.2, UFU-13#2.5.2 and UFU-13#2.1.3 present higher acylsugar concentrations than S. pennellii, in addition to higher productivity and number of fruits per plant. It is suggested to explore combinations between those genotypes previously described with UFU-8#2.4.1 to obtain hybrids with high acylsugar concentrations, two-spotted spider mite resistance, high productivity and increased fruit mass.

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Gunning, Vanda, Kyriakos Tzafestas, Helen Sparrow, Emily J. Johnston, Andrew S. Brentnall, Jennifer R. Potts, Elizabeth L. Rylott, and Neil C. Bruce. "Arabidopsis Glutathione Transferases U24 and U25 Exhibit a Range of Detoxification Activities with the Environmental Pollutant and Explosive, 2,4,6-Trinitrotoluene." Plant Physiology 165, no. 2 (April 14, 2014): 854–65. http://dx.doi.org/10.1104/pp.114.237180.

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Casadio, Paolo, Giulia Magnarelli, Mariangela La Rosa, Andrea Alletto, Alessandro Arena, Enrico Fontana, Ciro Morra, et al. "Uterine Fundus Remodeling after Hysteroscopic Metroplasty: A Prospective Pilot Study." Journal of Clinical Medicine 10, no. 2 (January 12, 2021): 260. http://dx.doi.org/10.3390/jcm10020260.

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The septate uterus is the most common congenital uterine malformation and is treated by hysteroscopic metroplasty. There are few studies on the fundal uterine changes that occur after surgery. We designed a pilot prospective observational study to evaluate by three-dimensional transvaginal ultrasound (3D-TVS) the changes not only of the internal fundal uterine profile, but also of the external one, after hysteroscopic metroplasty. Sixty women who underwent hysteroscopic metroplasty for partial or complete uterine septum (U2a and U2b subclasses of ESHRE/ESGE classification) were enrolled. We performed 3D-TVS after surgery confirming optimal removal of the septum. However, at ultrasound follow-up after three months, we observed a significant increase (p < 0.001) in the residual septum (Zr) (3.7 mm (95% CI: 3.1–4.4)), the myometrial wall thickness (Y) (2.5 mm (95% CI: 2.0–3.0)) and the total fundal wall thickness (Y + Zr) (6.2 mm (95% CI: 5.5–6.9)). Forty-three patients (72%) required a second step of hysteroscopic metroplasty. Moreover, the shape of uterine fundus changed in 58% of cases. We actually observed a remodeling of the uterine fundus with modifications of its external and internal profiles. Therefore, we propose to always perform a second ultrasound look at least three months after the metroplasty to identify cases that require a second- step metroplasty.

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Jacinto, Ana Carolina Pires, Aline José da Silveira, Isadora Gonçalves da Silva, Renata Castoldi, Carolina Andrade Franco, Rafael Resende Finzi, Marcus Vinícius Marin, Leila Trevisan Braz, and Gabriel Mascarenhas Maciel. "Comparison of methods to evaluate resistance of lettuce genotypes against Bremia lactucae." AUGUST 2020, no. 14(08):2020 (August 20, 2020): 1283–87. http://dx.doi.org/10.21475/ajcs.20.14.08.p2435.

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For the lettuce crop, there is no specific or standard methodology to evaluate genotype resistance of lettuce against downy mildew. Therefore, the aim of this work was to compare three methodologies for the identification of resistance to downy mildew. The experiment was carried out at Universidade Federal de Uberlândia, Monte Carmelo Campus between 2017 and 2018. The statistical method used was a completely randomized design with 12 treatments (cultivar Solaris, used as a control; and 11 genotypes of lettuce F5: 6: UFU-Crespa 75 # 2, UFU-Crespa 189 # 2, UFU-Crespa 206 # 1, UFU-Lisa 66 # 3, UFU-Lisa 66 # 7, UFU-Lisa 215 # 3, UFU-Lisa 215 # 6, UFU-Lisa 215 # 10, UFU-Lisa 215 # 12, UFU-Lisa 215 # 13, UFU-Lisa 215 # 14) and four replications. The seeding of genotypes was carried out in transparent boxes and after 15 days the inoculation was performed using a spore suspension (1x104 sporangia/ml) and sterile deionized water for the controls. The disease progression was assessed by three methods: Mesquita, Dickinson & Crute and Horsfall & Barrat. The data were standardized and submitted to the univariate analysis of variance by the F test and multivariate analyzes. The univariate clustering results allowed the separation of the genotypes into two distinct resistance groups for the Dickinson & Crute and Mesquita methods. In the multivariate analysis, more formation of groups among genotypes with different levels of resistance to downy mildew in the Mesquita method was observed. The methodology proposed by Mesquita was more efficient in discriminating genotypes with different levels of resistance to downy mildew, separating them in a larger number of groups.

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Lim, Chiaw-Hwee, Shang-Wei Chong, and Yun-Jin Jiang. "Udu Deficiency Activates DNA Damage Checkpoint." Molecular Biology of the Cell 20, no. 19 (October 2009): 4183–93. http://dx.doi.org/10.1091/mbc.e09-02-0109.

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Udu has been shown to play an essential role during blood cell development; however, its roles in other cellular processes remain largely unexplored. In addition, ugly duckling (udu) mutants exhibited somite and myotome boundary defects. Our fluorescence-activated cell sorting analysis also showed that the loss of udu function resulted in defective cell cycle progression and comet assay indicated the presence of increased DNA damage in udutu24 mutants. We further showed that the extensive p53-dependent apoptosis in udutu24 mutants is a consequence of activation in the Atm–Chk2 pathway. Udu seems not to be required for DNA repair, because both wild-type and udu embryos similarly respond to and recover from UV treatment. Yeast two-hybrid and coimmunoprecipitation data demonstrated that PAH-L repeats and SANT-L domain of Udu interacts with MCM3 and MCM4. Furthermore, Udu is colocalized with 5-bromo-2′-deoxyuridine and heterochromatin during DNA replication, suggesting a role in maintaining genome integrity.

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Graf, Solomon A., Chelle L. Wheat, Madeline C. Frost, Keith Sigel, Steven B. Zeliadt, and Emily C. Williams. "Unhealthy alcohol use and toxicity of concurrent chemoradiation for head and neck cancer." Journal of Clinical Oncology 37, no. 15_suppl (May 20, 2019): e17559-e17559. http://dx.doi.org/10.1200/jco.2019.37.15_suppl.e17559.

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e17559 Background: Unhealthy alcohol use (UAU) is an important risk factor for development head and neck squamous cell carcinoma (HNSCC), but any effect on treatment outcomes is not well understood. The Veterans Health Administration (VHA) annually screens outpatients for UAU with the validated Alcohol Use Disorders Identification Test Consumption (AUDIT-C). Methods: Using national VHA data we retrospectively identified patients administered upfront radiation with concurrent systemic therapy (chemo- and/or immuno- therapy) for stage III-IVb HNSCC diagnosed 2008 –2017 and included males with a prior-year AUDIT-C. Regression models were fit to assess associations between AUDIT-C risk groups [low-level use (score 1-3), moderate UAU (4-7), severe UAU (≥ 8)] and treatment toxicity. Models were adjusted for a priori defined covariates including smoking and variables related to demographics, comorbidities, and cancer diagnosis and treatment. Results: Among 3,094 patients, 46.7% screened positive for UAU: 23.9% with moderate UAU and 22.9% with severe UAU. Compared to patients with low-level alcohol use, those with severe UAU were younger (mean age 65 vs 67 years) and more frequently active smokers (63.4% vs 36.2%) and underweight (11.2% vs 3.5%) ( p for all comparisons < 0.05). There was no significant difference between alcohol use groups in race/ethnicity, cancer stage, or systemic treatment agent used. In adjusted models, severe UAU was associated with lower risk of nausea [adjusted odds ratio (AOR) 0.63, 95% CI 0.47 – 0.84], ED visits (AOR 0.79, CI 0.63 – 0.99), and hospitalizations during treatment (AOR 0.78, CI 0.62 – 0.98). UAU was not associated with a composite measure of complications of infection or organ damage (AOR 0.94, CI 0.74 – 1.20), severe weight loss (AOR 0.83, CI 0.66 – 1.05), or mortality within 100 days of completing treatment (AOR 1.01, CI 0.62 – 1.66). Conclusions: In this large cohort of male patients in the VHA treated for locoregionally advanced HNSCC with concurrent chemoradiation, moderate and severe UAU is common. UAU is not associated with increased toxicity of treatment, and future research is required to define its place in treatment selection, supportive care, and counseling.

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Sang, Yurou, Rui Zhang, A. Louise Creagh, Charles A. Haynes, and Suzana K. Straus. "Interactions of U24 from Roseolovirus with WW domains: canonical vs noncanonical." Biochemistry and Cell Biology 95, no. 3 (June 2017): 350–58. http://dx.doi.org/10.1139/bcb-2016-0250.

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U24 is a C-terminal membrane-anchored protein found in both human herpes virus type 6 and 7 (HHV-6 and HHV-7), with an N-terminal segment that is rich in prolines (PPxY motif in both HHV-6A and 7; PxxP motif in HHV-6A). Previous work has shown that U24 interacts strongly with Nedd4 WW domains, in particular, hNedd4L-WW3*. It was also shown that this interaction depends strongly on the nature of the amino acids that are upstream from the PY motif in U24. In this contribution, data was obtained from pull-downs, isothermal titration calorimetry, and NMR to further determine what modulates U24:WW domain interactions. Specifically, 3 non-canonical WW domains from human Smad ubiquitination regulatory factor (Smurf), namely hSmurf2-WW2, hSmurf2-WW3, and a tandem construct hSmurf2-WW2 + 3, were studied. Overall, the interactions between U24 and these Smurf WW domains were found to be weaker than those in U24:Nedd4 WW domain pairs, suggesting that U24 function is tightly linked to specific E3 ubiqitin ligases.

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33

Adeel, Dr Z. "Unu monitor." Global Environmental Change 11, no. 1 (April 2001): 97. http://dx.doi.org/10.1016/s0959-3780(00)00065-0.

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ADEEL, Z. "UNU Monitor." Global Environmental Change 13, no. 1 (April 2003): 61. http://dx.doi.org/10.1016/s0959-3780(03)00002-5.

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MABUYA, L. T. L., C. T. MSIMANG, and M. S. S. Gcumisa. "UCU OLUMHLOPHE." South African Journal of African Languages 16, sup1 (January 1996): 88–98. http://dx.doi.org/10.1080/02572117.1996.10587150.

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Cornille, Jean-Louis. "Ubu Chassé." Nottingham French Studies 37, no. 2 (September 1998): 48–61. http://dx.doi.org/10.3366/nfs.1998-2.005.

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Borgese, Elizabeth Mann. "UNU monitor." Global Environmental Change 4, no. 1 (March 1994): 78–86. http://dx.doi.org/10.1016/0959-3780(94)90023-x.

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Uitto, Juha I. "UNU Monitor." Global Environmental Change 5, no. 1 (March 1995): 65–69. http://dx.doi.org/10.1016/0959-3780(95)00025-j.

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Uitto, Juha I. "UNU monitor." Global Environmental Change 1, no. 5 (December 1991): 407–10. http://dx.doi.org/10.1016/0959-3780(91)90006-f.

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Rasool, S. Ichtiaque. "UNU monitor." Global Environmental Change 2, no. 1 (March 1992): 59–65. http://dx.doi.org/10.1016/0959-3780(92)90036-7.

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Ives, Jack D., and Juha I. Uitto. "UNU monitor." Global Environmental Change 4, no. 3 (September 1994): 261–64. http://dx.doi.org/10.1016/0959-3780(94)90006-x.

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Nicoloso, M., M. Caizergues-Ferrer, B. Michot, M. C. Azum, and J. P. Bachellerie. "U20, a novel small nucleolar RNA, is encoded in an intron of the nucleolin gene in mammals." Molecular and Cellular Biology 14, no. 9 (September 1994): 5766–76. http://dx.doi.org/10.1128/mcb.14.9.5766.

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We have found that intron 11 of the nucleolin gene in humans and rodents encodes a previously unidentified small nucleolar RNA, termed U20. The single-copy U20 sequence is located on the same DNA strand as the nucleolin mRNA. U20 RNA, which does not possess a trimethyl cap, appears to result from intronic RNA processing and not from transcription of an independent gene. In mammals, U20 RNA is an 80-nucleotide-long, metabolically stable species, present at about 7 x 10(3) molecules per exponentially growing HeLa cell. It has a nucleolar localization, as indicated by fluorescence microscopy following in situ hybridization with digoxigenin-labeled oligonucleotides. U20 RNA contains the box C and box D sequence motifs, hallmarks of most small nucleolar RNAs reported to date, and is immunoprecipitated by antifibrillarin antibodies. It also exhibits a 5'-3' terminal stem bracketing the box C-box D motifs like U14, U15, U16, or Y RNA. A U20 homolog of similar size has been detected in all vertebrate classes by Northern (RNA) hybridization with mammalian oligonucleotide probes. U20 RNA contains an extended region (21 nucleotides) of perfect complementarity with a phylogenetically conserved sequence in 18S rRNA. This complementarity is strongly preserved among distant vertebrates, suggesting that U20 RNA may be involved in the formation of the small ribosomal subunit like nucleolin, the product of its host gene.

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Nicoloso, M., M. Caizergues-Ferrer, B. Michot, M. C. Azum, and J. P. Bachellerie. "U20, a novel small nucleolar RNA, is encoded in an intron of the nucleolin gene in mammals." Molecular and Cellular Biology 14, no. 9 (September 1994): 5766–76. http://dx.doi.org/10.1128/mcb.14.9.5766-5776.1994.

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We have found that intron 11 of the nucleolin gene in humans and rodents encodes a previously unidentified small nucleolar RNA, termed U20. The single-copy U20 sequence is located on the same DNA strand as the nucleolin mRNA. U20 RNA, which does not possess a trimethyl cap, appears to result from intronic RNA processing and not from transcription of an independent gene. In mammals, U20 RNA is an 80-nucleotide-long, metabolically stable species, present at about 7 x 10(3) molecules per exponentially growing HeLa cell. It has a nucleolar localization, as indicated by fluorescence microscopy following in situ hybridization with digoxigenin-labeled oligonucleotides. U20 RNA contains the box C and box D sequence motifs, hallmarks of most small nucleolar RNAs reported to date, and is immunoprecipitated by antifibrillarin antibodies. It also exhibits a 5'-3' terminal stem bracketing the box C-box D motifs like U14, U15, U16, or Y RNA. A U20 homolog of similar size has been detected in all vertebrate classes by Northern (RNA) hybridization with mammalian oligonucleotide probes. U20 RNA contains an extended region (21 nucleotides) of perfect complementarity with a phylogenetically conserved sequence in 18S rRNA. This complementarity is strongly preserved among distant vertebrates, suggesting that U20 RNA may be involved in the formation of the small ribosomal subunit like nucleolin, the product of its host gene.

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Maciel, Gabriel M., José MQ Luz, Saulo FB Campos, Rafael R. Finzi, and Breno NR Azevedo. "Heterosis in okra hybrids obtained by hybridization of two methods: traditional and experimental." Horticultura Brasileira 35, no. 1 (March 2017): 119–23. http://dx.doi.org/10.1590/s0102-053620170118.

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ABSTRACT High heterosis values can be obtained using hybrid okra seeds. However, despite high heterotic values, it is very difficult to produce hybrid okra seeds. The objective of this study was to evaluate an experimental methodology of hybridization. Two different methods of hybridization were used: traditional manual hybridization with complete emasculation followed by hand pollination (artificial) and, an experimental methodology, performing manual hybridization with incomplete emasculation followed by entomophilous natural pollination between two inbred lines (UFU-QB-040D and UFU-QB-107G).These inbred lines were obtained from three selection cycles. Three hybrid types were obtained from the two hybridization methods: F1 THM(UFU-QB-040D x UFU-QB-107G), F1 IHM(UFU-QB-107G x UFU-QB-040D) and F1 IHM(UFU-QB-040D x UFU-QB-107G). The resulting hybrid seeds and their parents were evaluated via an experiment set up in a randomized block design with four repetitions. We evaluated fruit production per plant, fruits per plant, number of branchess per plant, superiority of hybrids relative to parents (h) and heterosis (%). At the end of the cycle, morphological characterizations was done of the leaves (pubescence, length and width) and fruit (length, diameter and shape). Heterosis resulting from the incomplete emasculation followed by natural insect pollination was similar to that from the traditional hybrid method, being a viable alternative for the production of hybrid okra seeds without losses in heterosis.

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Rajan, K. Shanmugha, Tirza Doniger, Smadar Cohen-Chalamish, Dana Chen, Oz Semo, Saurav Aryal, Efrat Glick Saar, et al. "Pseudouridines on Trypanosoma brucei spliceosomal small nuclear RNAs and their implication for RNA and protein interactions." Nucleic Acids Research 47, no. 14 (May 31, 2019): 7633–47. http://dx.doi.org/10.1093/nar/gkz477.

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Abstract The parasite Trypanosoma brucei, the causative agent of sleeping sickness, cycles between an insect and a mammalian host. Here, we investigated the presence of pseudouridines (Ψs) on the spliceosomal small nuclear RNAs (snRNAs), which may enable growth at the very different temperatures characterizing the two hosts. To this end, we performed the first high-throughput mapping of spliceosomal snRNA Ψs by small RNA Ψ-seq. The analysis revealed 42 Ψs on T. brucei snRNAs, which is the highest number reported so far. We show that a trypanosome protein analogous to human protein WDR79, is essential for guiding Ψ on snRNAs but not on rRNAs. snoRNA species implicated in snRNA pseudouridylation were identified by a genome-wide approach based on ligation of RNAs following in vivo UV cross-linking. snRNA Ψs are guided by single hairpin snoRNAs, also implicated in rRNA modification. Depletion of such guiding snoRNA by RNAi compromised the guided modification on snRNA and reduced parasite growth at elevated temperatures. We further demonstrate that Ψ strengthens U4/U6 RNA–RNA and U2B"/U2A’ proteins-U2 snRNA interaction at elevated temperatures. The existence of single hairpin RNAs that modify both the spliceosome and ribosome RNAs is unique for these parasites, and may be related to their ability to cycle between their two hosts that differ in temperature.

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Lorković, Zdravko J., Julia Hilscher, and Andrea Barta. "Use of Fluorescent Protein Tags to Study Nuclear Organization of the Spliceosomal Machinery in Transiently Transformed Living Plant Cells." Molecular Biology of the Cell 15, no. 7 (July 2004): 3233–43. http://dx.doi.org/10.1091/mbc.e04-01-0055.

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Although early studies suggested that little compartmentalization exists within the nucleus, more recent studies on metazoan systems have identified a still increasing number of specific subnuclear compartments. Some of these compartments are dynamic structures; indeed, protein and RNA-protein components can cycle between different domains. This is particularly evident for RNA processing components. In plants, lack of tools has hampered studies on nuclear compartmentalization and dynamics of RNA processing components. Here, we show that transient expression of fluorescent protein fusions of U1 and U2 small nuclear ribonucleoprotein particle (snRNP)-specific proteins U1-70K, U2B″, and U2A ′, nucleolar proteins Nop10 and PRH75, and serine-arginine-rich proteins in plant protoplasts results in their correct localization. Furthermore, snRNP-specific proteins also were correctly assembled into mature snRNPs. This system allowed a systematic analysis of the cellular localization of Arabidopsis serine-arginine-rich proteins, which, like their animal counterparts, localize to speckles but not to nucleoli and Cajal bodies. Finally, markers for three different nuclear compartments, namely, nucleoli, Cajal bodies, and speckles, have been established and were shown to be applicable for colocalization studies in living plant protoplasts. Thus, transient expression of proteins tagged with four different fluorescent proteins is a suitable system for studying the nuclear organization of spliceosomal proteins in living plant cells and should therefore allow studies of their dynamics as well.

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Bethune, David N., Angus Chu, and M. Cathryn Ryan. "Passive evaporation of source-separated urine from dry toilets: prototype design and field testing using municipal water." Journal of Water, Sanitation and Hygiene for Development 5, no. 3 (May 22, 2015): 392–401. http://dx.doi.org/10.2166/washdev.2015.158.

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A prototype urine evaporation unit (UEU) that removes water from human urine produced from a urine-diverting dry toilet using passive solar evaporation was designed and field-tested at a meteorological station. Municipal water was evaporated on vertically stacked plastic cafeteria-style trays that create a large evaporation surface with a small land-area footprint. The trays were located inside a Plexiglas® enclosure exposed to UV light while passively heating the UEU like a solar oven. A metal black chimney also heated up in the sun, causing air to enter the UEU at the front of the UEU through a louvered vent, flow across each tray, and then exit at the back up through the chimney. The UEU was field-tested in a semi-arid temperate climate (Calgary, Canada) from 22 August to 5 November 2013. The average UEU evaporation rate was 3.2 L/day (0.66 mm), varying from 0.4 L/day (0.08 mm/day) on a cloudy day to 8.8 L/day (1.82 mm) on a sunny day. A multiple-regression analysis indicates that 63% of the UEU evaporation rate can be explained by changes in air temperature, wind speed and incoming solar radiation, thus allowing for predictions of the UEU's relative evaporation potential in other climates.

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Hetzer, Martin, and Iain W. Mattaj. "An Atp-Dependent, Ran-Independent Mechanism for Nuclear Import of the U1a and U2b′′ Spliceosome Proteins." Journal of Cell Biology 148, no. 2 (January 24, 2000): 293–304. http://dx.doi.org/10.1083/jcb.148.2.293.

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Nuclear import of the two uracil-rich small nuclear ribonucleoprotein (U snRNP) components U1A and U2B′′ is mediated by unusually long and complex nuclear localization signals (NLSs). Here we investigate nuclear import of U1A and U2B′′ in vitro and demonstrate that it occurs by an active, saturable process. Several lines of evidence suggest that import of the two proteins occurs by an import mechanism different to those characterized previously. No cross competition is seen with a variety of previously studied NLSs. In contrast to import mediated by members of the importin-β family of nucleocytoplasmic transport receptors, U1A/U2B′′ import is not inhibited by either nonhydrolyzable guanosine triphosphate (GTP) analogues or by a mutant of the GTPase Ran that is incapable of GTP hydrolysis. Adenosine triphosphate is capable of supporting U1A and U2B′′ import, whereas neither nonhydrolyzable adenosine triphosphate analogues nor GTP can do so. U1A and U2B′′ import in vitro does not require the addition of soluble cytosolic proteins, but a factor or factors required for U1A and U2B′′ import remains tightly associated with the nuclear fraction of conventionally permeabilized cells. This activity can be solubilized in the presence of elevated MgCl2. These data suggest that U1A and U2B′′ import into the nucleus occurs by a hitherto uncharacterized mechanism.

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Ho, Kendall, and Zena Sharman. "E-health and the Universitas 21 organization: 1. Global e-health through synergy." Journal of Telemedicine and Telecare 11, no. 5 (July 1, 2005): 218–20. http://dx.doi.org/10.1258/1357633054471902.

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The Universitas 21 (U21) organization funded a one-year project to examine global e-health. An e-health steering committee surveyed the opinions of e-health researchers at U21 member schools and conducted a literature review. Information about key themes was analysed and the findings were summarized. The steering committee recommended an eight-step strategy to establish a sustainable endeavour in global e-health. This included implementing a dissemination strategy within the U21 organization to engage a progressively larger community of faculty members and others, and translating e-health knowledge into global practice in those areas in which the U21 has special expertise. While the recommendations in the discussion paper are specific to the U21 organization, the e-health steering committee believes they can be generalized and applied to any globally minded educational or research institutions seeking to contribute to e-health.

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Mendes Gimenes, Oliria Mendes. "Educação a distância online na Universidade Federal de Uberlândia: um percurso em consolidação." Revista EDaPECI 14, no. 1 (April 30, 2014): 204–20. http://dx.doi.org/10.29276/redapeci.2014.14.11556.204-220.

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A educação a distância (EaD) desde que foi contemplada na legislação vigente de nosso país, vem conquistando espaço em nossa sociedade e se consolidando como modalidade de ensino. Nessa perspectiva, este trabalho tem como objetivo analisar essa modalidade de ensino na legislação educacional brasileira, bem como apresentar a sua constituição na Universidade Federal de Uberlândia (UFU). Trata-se de um estudo bibliográfico e documental, com coleta de dados no website institucional do Centro de Educação a Distância da UFU (CEaD/UFU). A partir desses levantamentos apresentamos um breve histórico com base na LDB 9394/96 e sua implantação como modalidade de ensino no Brasil, bem como o percurso e sua constituição na UFU. Ao final, consideramos que o percurso na instituição tem avançado e vem conquistando espaço dentro do ambiente acadêmico, confirmando assim, os esforços desenvolvidos pelo CEaD, gestor da EaD na UFU. Palavras-chave: Educação a distância online. Ensino Superior. Sistema UAB.

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Journal articles on the topic 'U2U'

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