Numerical models based on the two‐dimensional shallow water equations (2D‐SWE) are routinely used in flood risk management and inundation studies. However, most of these models do not adequately ...account for vertically confined flow conditions that can appear during inundations, due to the presence of hydraulic structures such as bridges, culverts, or underground river reaches. In this article we propose a new mathematical modification of the standard 2D‐SWE, inspired by the two‐component pressure approach for 1D flows, to address the issue of transient vertically confined flows including transitions between free surface and pressurized conditions. A finite volume discretization to solve the proposed system of equations is proposed and analyzed. Various test cases are used to show the numerical stability and accuracy of the discretization, and to validate the proposed formulation. Results show that the proposed method is numerically stable, accurate, mass conservative, and preserves the C‐property. It can also handle subcritical, supercritical, and transcritical flows under free surface or vertically confined conditions.
Most shallow water models based on the two‐dimensional (2D) Saint Venant equations do not consider the vertical confinement of the flow that commonly appears during inundations caused by the presence of bridges, culverts, or other hydraulic structures. In this article we present a modification of the standard 2D shallow water equations to cope with transient vertically confined flows. We present and analyze a finite volume discretization of the proposed equations that is stable, mass‐conservative, and well balanced.
Controlling the deposition of spin‐crossover (SCO) materials constitutes a crucial step for the integration of these bistable molecular systems in electronic devices. Moreover, the influence of ...functional surfaces, such as 2D materials, can be determinant on the properties of the deposited SCO film. In this work, ultrathin films of the SCO Hofmann‐type coordination polymer Fe(py)2{Pt(CN)4} (py = pyridine) onto monolayers of 1T and 2H MoS2 polytypes are grown. The resulting hybrid heterostructures are characterized by GIXRD, XAS, XPS, and EXAFS to get information on the structure and the specific interactions generated at the interface, as well as on the spin transition. The use of a layer‐by‐layer results in SCO/2D heterostructures, with crystalline and well‐oriented Fe(py)2{Pt(CN)4}. Unlike with conventional Au or SiO2 substrates, no intermediate self‐assembled monolayer is required, thanks to the surface S atoms. Furthermore, it is observed that the higher presence of Fe3+ in the 2H heterostructures hinders an effective spin transition for Fe(py)2{Pt(CN)4} films thinner than 8 nm. Remarkably, when using 1T MoS2, this transition is preserved in films as thin as 4 nm, due to the reducing character of this metallic substrate. These results highlight the active role that 2D materials play as substrates in hybrid molecular/2D heterostructures.
Spin‐crossover Hofmann‐type coordination polymer Fe(py)2{Pt(CN)4} is grown on 1T and 2H molybdenum disulfide (MoS2) monolayers. Detailed analysis of the hybrid heterostructures discloses that the 2D material plays an active role in the formation of the spin‐crossover film, with 1T MoS2 heterostructures preserving the spin transition in thinner films. The findings demonstrate the crucial function of 2D materials in hybrid molecular/2D heterostructures.
El presente artículo es el resultado de una indagación respecto a la obra del músico y productor discográfico de origen británico Daniel Dumile, mejor conocido por su nombre artístico MF DOOM. El ...enfoque fue cualitativo y se empleó el análisis discursivo con base en la semiótica estructural francesa. El objetivo consistió en identificar las strategias de articulación del yo a partir del proceso de enunciación musical de la letra y emparentarlo con otras manifestaciones artísticas del cantante. Se comprueba que el estilo lírico de Dumile depende de un muy delicado juego de desembragues y embragues enunciativos, los cualessirven de base para construir personajes en distintos momentos de sus composiciones y aproximándose lúdicamente al enunciatario.
We report a disease and mortality event involving swans, seals, and a fox at a wildlife rehabilitation center in the United Kingdom during late 2020. Five swans had onset of highly pathogenic avian ...influenza virus infection while in captivity. Subsequently, 5 seals and a fox died (or were euthanized) after onset of clinical disease. Avian-origin influenza A virus subtype H5N8 was retrospectively determined as the cause of disease. Infection in the seals manifested as seizures, and immunohistochemical and molecular testing on postmortem samples detected a neurologic distribution of viral products. The fox died overnight after sudden onset of inappetence, and postmortem tissues revealed neurologic and respiratory distribution of viral products. Live virus was isolated from the swans, seals, and the fox, and a single genetic change was detected as a potential adaptive mutation in the mammalian-derived viral sequences. No human influenza-like illness was reported in the weeks after the event.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Hydrological rehabilitation is widely used to improve soil conditions and promote passive recovery. However, climate variability that is seldom considered in restoration planning can affect ...hydrological rehabilitation goals.
We used long‐term observations to assess the effects of El Niño Southern Oscillation (ENSO) climate variability and hydrologic rehabilitation on tree recruitment and landscape cover changes in a South American mangrove complex.
ENSO climate variability and rehabilitation hydrology measure types collectively explained 88%, 90% and 70% of mangrove cover change rates in the whole mangrove system and porewater salinity in basin and riverine sites, respectively. Therefore, major and detrimental rehabilitation measures counterbalanced or reinforced the effects of ENSO phase intensity on the system. In addition, climate variability explained the rates of change of salinity in the basin site (58%).
Porewater salinity, its rates of change and ENSO explained 28%–75% of propagule density and seedling/sapling growth rates of Rhizophora mangle, Laguncularia racemosa and Avicennia germinans in representative basin and riverine sites.
Tree colonization in the basin site, under high irradiance, was triggered by high seedling/saplings diameter growth rates (0.5–1.6 cm year−1) of L. racemosa and R. mangle generated by strong porewater salinity drop rates during consecutive La Niña episodes, while widespread tree mortality occurred during a strong El Niño. Tree size categories were more stable to ENSO climate variability in the riverine site.
Synthesis and implications. This study shows that hydrologic rehabilitation effectiveness depended on its influence on freshwater flows and on the effects of ENSO climate variability. ENSO, porewater salinity and its rates of change regulated tree recruitment and landscape cover changes. Thus, besides porewater salinity, rates of change of porewater salinity, light availability and climate variability need to be included in monitoring and mangrove restoration planning to better understand and predict mangrove trajectories. Climate‐smart restoration in mangroves should implement the types of hydrological rehabilitation measures that offset or avoid reinforcing ENSO strong phases.
Resumen
La rehabilitación hidrológica es ampliamente utilizada para mejorar las condiciones del suelo y promover una recuperación pasiva de los ecosistemas. Sin embargo, la variabilidad climática que es poco considerada en la planificación de la restauración puede afectar los objetivos de la rehabilitación hidrológica
Se utilizaron observaciones de largo plazo para determinar los efectos de la variabilidad climática asociada a la Oscilación del Niño Sur ENOS y de la rehabilitación hidrológica en el reclutamiento de árboles y los cambios de cobertura del paisaje en un complejo de manglar suramericano
La variabilidad climática asociada a ENOS y los tipos de medidas de rehabilitación hidrológica explicaron en 88%, 90% y 70% las tasas de cambio de cobertura de manglar en todo el sistema y la salinidad intersticial en sitios de cuenca y ribera, respectivamente. Por lo tanto, las medidas de rehabilitación hidrológica más intensas y las medidas perjudiciales contrarrestaron o reforzaron los efectos de la intensidad de las fases ENOS en el sistema. Adicionalmente, la variabilidad climática explicó las tasas de cambio de la salinidad intersticial en el sitio de cuenca (58%)
La salinidad intersticial, sus tasas de cambio, y el ENOS explicaron en 28%–75% la densidad de propágulos y las tasas de crecimiento de plántulas en Rhizophora mangle, Laguncularia racemosa y Avicennia germinans en sitios de cuenca y ribera representativos.
La colonización de árboles en el sitio de cuenca, bajo alta irradiancia, fue desencadenado por altas de tasas de crecimiento diamétricas en las plántulas (0.5–1.6 cm year−1) de L. racemosa y R. mangle generadas por disminuciones fuertes de la salinidad intersticial durante años La Niña consecutivos. Por el contrario, una mortalidad extensiva de árboles ocurrió durante un El Niño fuerte. Las clases de tamaño arbóreas fueron más estables a la variabilidad climática de ENOS en el sitio de ribera.
Síntesis e implicaciones. Este estudio muestra que la efectividad de la rehabilitación hidrológica depende de su influencia en los flujos de agua dulce y de los efectos de la variabilidad climática asociada al ENOS. El ENOS, la salinidad intersticial y sus tasas de cambio regularon el reclutamiento de los árboles y los cambios de cobertura en el paisaje. Por lo tanto, además de la salinidad intersticial, sus tasas de cambio , la disponibilidad de luz y la variabilidad climática deben ser incluidas en el monitoreo y en la planificación de la restauración para entender y predecir mejor las trayectorias de los manglares. La restauración climáticamente inteligente deberá implementar los tipos de medidas de rehabilitación que contrarrestan o evitan reforzar las fases fuertes de ENOS.
This study shows that hydrologic rehabilitation effectiveness depended on its influence on freshwater flows and on the effects of ENSO climate variability. ENSO, porewater salinity and its rates of change regulated tree recruitment and landscape cover changes. Thus, besides porewater salinity, rates of change of porewater salinity, light availability and climate variability need to be included in monitoring and mangrove restoration planning to better understand and predict mangrove trajectories. Climate‐smart restoration in mangroves should implement the types of hydrological rehabilitation measures that offset or avoid reinforcing ENSO strong phases.
Abstract
Low-mass (≲1.2
M
⊙
) main-sequence stars lose angular momentum over time, leading to a decrease in their magnetic activity. The details of this rotation–activity relation remain poorly ...understood, however. Using observations of members of the ≈700 Myr old Praesepe and Hyades open clusters, we aim to characterize the rotation–activity relation for different tracers of activity at this age. To complement published data, we obtained new optical spectra for 250 Praesepe stars, new X-ray detections for 10, and new rotation periods for 28. These numbers for Hyads are 131, 23, and 137, respectively. The latter increases the number of Hyads with periods by 50%. We used these data to measure the fractional H
α
and X-ray luminosities,
L
H
α
/
L
bol
and
L
X
/
L
bol
, and to calculate Rossby numbers
R
o
. We found that at ≈700 Myr almost all M dwarfs exhibit H
α
emission, with binaries having the same overall color–H
α
equivalent width distribution as single stars. In the
R
o
–
L
H
α
/
L
bol
plane, unsaturated single stars follow a power law with index
β
= −5.9 ± 0.8 for
R
o
> 0.3. In the
R
o
–
L
X
/
L
bol
plane, we see evidence for supersaturation for single stars with
R
o
≲ 0.01, following a power law with index
β
sup
=
0.5
−
0.1
+
0.2
, supporting the hypothesis that the coronae of these stars are being centrifugally stripped. We found that the critical
R
o
value at which activity saturates is smaller for
L
X
/
L
bol
than for
L
H
α
/
L
bol
. Finally, we observed an almost 1:1 relation between
L
H
α
/
L
bol
and
L
X
/
L
bol
, suggesting that both the corona and the chromosphere experience similar magnetic heating.
Infection of chickens with avian influenza virus poses a global threat to both poultry production and human health that is not adequately controlled by vaccination or by biosecurity measures. A novel ...alternative strategy is to develop chickens that are genetically resistant to infection. We generated transgenic chickens expressing a short-hairpin RNA designed to function as a decoy that inhibits and blocks influenza virus polymerase and hence interferes with virus propagation. Susceptibility to primary challenge with highly pathogenic avian influenza virus and onward transmission dynamics were determined. Although the transgenic birds succumbed to the initial experimental challenge, onward transmission to both transgenic and nontransgenic birds was prevented.
El presente artículo propone un análisis semiótico-estructural de la película de Quentin Tarantino Los ocho más odiados (The Hateful Eight, 2015). Nuestro trabajo incorpora elementos provenientes de ...la narratología fílmica, en particular la idea del unreliable narrator de Emily Anderson, quien plantea la posibilidad de un narrador no confiable al interior del discurso. El análisis demuestra que el filme, tanto al nivel del relato como del discurso, presenta una serie de simulacros manipulatorios que les permiten a sus actantes organizar la dimensión cognitiva del saber y el creer. Se revela un dispositivo que no solo permite a los personajes engañar a otros con sus discursos, sino también al enunciador que opera en un nivel superior. De este modo, el filme convierte la subinformación y la contrainformación en sus instrumentos clave.
Transition Metal Dichalcogenides
In article number 2304954, Alicia Forment‐Aliaga, Eugenio Coronado, and co‐workers present 2D materials as non‐innocent substrates for the direct growth of a ...spin‐crossover polymer. By layer‐by‐layer solution method, crystalline and oriented films of Fe(py)2{Pt(CN)4} grow on 1T and 2H MoS2 layers. The charge transfer from 1T MoS2 to iron ions leads to a superior spin‐crossover effect in ultrathin films than when 2H‐MoS2 is used.
Abstract Since the reintroduction of African swine fever virus (ASFV) in Europe in 2007 and its subsequent spread to Asia, wild boar has played a crucial role in maintaining and disseminating the ...virus. There are significant gaps in the knowledge regarding infection dynamics and disease pathogenesis in domestic pigs and wild boar, particularly at the early infection stage. We aimed to compare domestic pigs and wild boar infected intranasally to mimic natural infection with one of the original highly virulent genotype II ASFV isolates (Armenia 2007). The study involved euthanising three domestic pigs and three wild boar on days 1, 2, 3, and 5 post-infection, while four domestic pigs and four wild boar were monitored until they reached a humane endpoint. The parameters assessed included clinical signs, macroscopic lesions, viremia levels, tissue viral load, and virus shedding in nasal and rectal swabs from day 1 post-infection. Compared with domestic pigs, wild boar were more susceptible to ASFV, with a shorter incubation period and earlier onset of clinical signs. While wild boar reached a humane endpoint earlier than domestic pigs did, the macroscopic lesions were comparatively less severe. In addition, wild boar had earlier viremia, and the virus was also detected earlier in tissues. The medial retropharyngeal lymph nodes were identified as key portals for ASFV infection in both subspecies. No viral genome was detected in nasal or rectal swabs until shortly before reaching the humane endpoint in both domestic pigs and wild boar, suggesting limited virus shedding in acute infections.
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