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This paper provides a numerical analysis of the topological valley kink states along both zigzag and armchair domain walls of a dielectric two-dimensional photonic crystal (PC), considering the photonic energy band folding mechanism. By engineering the side length of triangular holes in a honeycomb PC, we created inequivalent valleys in the momentum space. We utilized two adjacent valley PCs with inverted structures to induce a topological transition of the TE mode energy band as it crossed the interface. Further research into the projected energy bands along both zigzag and armchair directions revealed that topologically protected valley kink states can be supported by both configurations. The zigzag interface enabled valley waveguides to transport chiral optical fields at the 0°, 60°, and 120° bending angles, while maintaining their backscattering immune properties. The armchair interface, on the other hand, supported the straight propagation. By combining both armchair and zigzag interfaces, the valley waveguide can facilitate bending propagation at 90° and 180°, while also enabling the equal splitting of chiral fields at the intersection between these two interfaces. Our analyzation can be helpful to improve the applications of valley waveguides in integrated photonics. [ABSTRACT FROM AUTHOR]

Histoplasma capsulatum is a dimorphic fungi endemic to the Ohio and Mississippi River valleys. Immunocompetent persons who become infected are generally asymptomatic or present with mild symptoms. Symptomatic disease is seen primarily in immunocompromised patients with pulmonary manifestations being the most common presentation. We present a case of a young HIV-negative male who required 4 exploratory laparotomies over the course of 4 months during 2 hospitalizations due to discrete perforations of the ileum and jejunum caused by biopsy-proven gastrointestinal histoplasmosis despite maximal medical therapy as well as a gastric perforation. [ABSTRACT FROM AUTHOR]

This article explores the development of social archaeology in Latin America, particularly in relation to postcolonial and decolonial frameworks. It discusses the limitations of early social archaeology in challenging Western hierarchies and patriarchal practices. The article also examines the influence of postcolonial critique and decolonial thinking on South American archaeology, emphasizing the acceptance of diverse critical perspectives. It introduces the concept of "heritage companionship" and highlights the work of the CIIVAC collective in Argentina, which engages in interdisciplinary research and collaborates with local communities to promote heritage preservation and community development. The article concludes by emphasizing the importance of decolonizing archaeology and adopting inclusive practices in academia and heritage management. [Extracted from the article]

Humans have had profound and environmentally changing impacts on land cover, and China has many examples of this. It has been recognised for some time that middle to late Holocene forests in China have undergone changes that are best described as due to human impacts. Hence the Holocene has seen sometimes gradual and sometimes abrupt changes from forest dynamics driven by natural forces to those dominated by human impacts. This leads to a conclusion that it is often difficult to disentangle natural and anthropogenic controls on forest composition. In many cases records show minor changes in the early Holocene giving way to intense changes as agriculture expanded. The two earliest centres of extensive forest changes from 6 to 5 kyr BP were in the middle to lower Yellow and lower Yangtze valleys, where millet and rice agriculture developed. Major forest clearing was later in other areas, including the Pearl River valley, Northeast China and Yunnan. Forest clearing for agriculture was widespread in eastern China by 2 kyr BP. Where data is available it seems that initial clearing took place in valleys adjacent to rivers, presumably because these were the preferred living places for early farmers. Then gradually spread to nearby slopes. New approaches and technologies were needed to achieve this. The records show that north east China, north of the Liao River, and the mountains of central China were amongst the last places to record forest clearing, in some cases just within the last few hundred years, or not at all. [ABSTRACT FROM AUTHOR]

Seismic amplification effects are a common occurrence in V-shaped valleys. A method is presented for incorporating the amplification effects in the stability assessment of V-shaped fill slopes based on the limit equilibrium (LE) method coupled with the pseudo-static approach. The proposed LE method uses a variationally derived three-dimensional (3D) rotational failure mechanism to produce stability charts for slopes. A series of parameter analyses are conducted to investigate the influences of seismic load and the geometric parameters on the 3D stability and the most critical slip surface for V-shaped fill slopes. The findings indicate that the reduction in the slope stability triggered by the seismic amplification effects is notable. The boundary effects are positively correlated with the inclination of the valley side slope and negatively correlated with the width of the valley bottom. The face failure mode is dominated in the cases where the boundary effects are significant. Furthermore, an explicit expression equation of the safety factor, the stability equation, is obtained by regression analysis. This stability equation has excellent accuracy and can be used in practical engineering to provide a convenient assessment for V-shaped fill slopes. [ABSTRACT FROM AUTHOR]

The 2D ferrovalley semiconductor (FVSC) with spontaneous valley polarization offers an exciting material platform for probing Berry phase physics. How FVSC can be incorporated in valleytronic device applications, however, remain an open question. Here, the concept of metal/semiconductor (MS) contact into the realm of valleytronics is generalized. A half‐valley Ohmic contact is proposed based on FVSC/graphene heterostructure, where the two valleys of FVSC separately forms Ohmic and Schottky contacts with those of graphene, thus allowing current to be valley‐selectively injected through the 'Ohmic' valley while being blocked in the 'Schottky' valley. A theory of contact‐limited valley‐contrasting current injection is developed and such transport mechanism can produce gate‐tunable valley‐polarized injection current. Using RuCl2/graphene heterostructure as an example, a device concept of valleytronic barristor is illustrated, where high valley polarization efficiency and sizable current on/off ratio, can be achieved under experimentally feasible electrostatic gating conditions. These findings uncover contact‐limited valley‐contrasting current injection as an efficient mechanism for valley polarization manipulation, and reveals the potential of valleytronic MS contact as a functional building block of valleytronic device technology. [ABSTRACT FROM AUTHOR]

This study compares the ozone valleys over the Tibetan Plateau (TP) and the Rocky Mountains (RM) using the ERA5 reanalysis data set. The dynamical transport of the ozone over these two regions is analyzed using the Lorenz circulation decomposition method. The ozone content valley over TP is observed around 200–50 hPa (upper troposphere and lower stratosphere, or UTLS), and that over RM is around 300–100 hPa. It is shown that the TP ozone content is smaller than that over RM. By analyzing the spatiotemporal distribution of the ozone content and the general circulation, the anticyclone over Southern Asian (SAH) plays a significant role in existence of the TP ozone valley, and the ozone content flux reaches its maximum in July. Large‐scale terrain and related general circulation determine the ozone valley appearance. Further analysis suggests that stationary transport has a larger impact on the ozone valley formation than the transient transport. The transport by the zonal circulation nearly cancels out most of that by the meridional circulation, due to the fact that the zonal transport magnitude is nearly equal to the meridional transport. The transport center over the RM is much weaker than that over the TP. Furthermore, the contrasts between transient and stationary transports are less evident over RM than over TP. The eddy‐driven stationary ozone transport flux significantly impacts the development of the two low ozone centers across these large terrains. Plain Language Summary: Extremely low ozone content has been observed over the Arctic, Antarctic, and high‐terrain regions. Ozone absorbs most wavelengths of UV radiation, therefore understanding the formation of ozone valley plays an important role for climate research. We compared the climatic features of ozone valleys over two high‐terrain regions (i.e., Tibetan Plateau (TP) and Rocky Mountains (RM)). Dynamical transport is investigated using Lorenz circulation decomposition, and it shows the eddy stationary transport has a significant impact. The total dynamical transport of ozone over the RM is much weaker than that over the TP. This study advances our knowledge of ozone valley formation over these two regions. Key Points: The ozone valleys exist over both the Tibetan Plateau (TP) and the Rocky Mountains (RM)The TP ozone valley is stronger and locates higher than that over the RM, consistent with the terrain contrastThe stationary transport by the climatological eddies dominates the ozone budget for both high‐terrain regions [ABSTRACT FROM AUTHOR]

A field campaign in a valley near Seefeld, Austria, well known for the frequent occurrence of cold‐air pools, was conducted to identify the processes leading to the formation and erosion of the cold‐air pool. Here, we focus on a case study in January 2020 that featured cold‐air pool formation interrupted by a wind disturbance. Simulations with the Weather Research and Forecasting model were performed at a horizontal grid spacing of 40 m and compared with measurement results. The model was able to reproduce the intense cooling in the beginning of the night and the cold‐air pool erosion in the middle of the night caused by the wind disturbance, but stronger winds than observed prevented the cold‐air pool from fully re‐establishing in the model after the disturbance. The dominant cooling processes were long‐wave radiative heat loss and turbulent exchange, both of which are parametrized and cool the air locally. Advection was the most important warming contribution during the cold‐air pool disturbances, especially its cross‐valley and vertical components. Owing to numerical constraints and the shallow nature of the cold‐air pool, its extent was limited to the lowest model level. Further improvements to the cold‐air pool's representation in the model would require a finer grid resolution. [ABSTRACT FROM AUTHOR]

Alhagi pseudalhagi, which grows in the arid zone of the Atyrau region, and an assessment of the current state of its raw material reserves were studied. Botanical characteristics, ontogenetic spectra, morphological indicators, productivity, areas of thickets, and reserves of raw materials of above-ground organs were assessed. The structural parameters of these populations in the Zhangyr and Coneu Rivers valleys, in the vicinity of Imankara Mountain, and on the Taisoigan sands were studied. It was established that the species composition of the populations includes 63 species from 54 genera and 30 families. The most common species include 49 species, which, according to their occurrence in populations of A. pseudalhagi, are distributed in the following classes: 17 species—class II (0–20%); 7 species—class III (41–60%); and 2 species—classes IV (61–80%) and V (81–100%). The maximum similarity in species composition was noted between populations in the Zhangyr and Coneu Rivers valleys. The highest morphometric indicators were observed among the population of the Coneu river valley, and the lowest are located on the Taisoigan sands. Analysis of the age spectra made it possible to determine that the populations in the Zhangyr and Coneu River valleys are characterized as young and those in the area of Imankara Mountain and on the Taisoigan sands as stable and middle-aged. [ABSTRACT FROM AUTHOR]

Progress on two-dimensional materials has shown that valleys, as energy extrema in a hexagonal first Brillouin zone, provide a new degree of freedom for information manipulation. Then, valley Hall topological insulators supporting such-polarized edge states on boundaries were set up accordingly. In this paper, a two-dimensional valley crystal composed of six tunable dielectric triangular pillars in each unit cell is proposed in the photonic sense of a deformed Su–Schrieffer–Heeger model. We reveal the vortex nature of valley states and establish the selection rules for valley-polarized states. Based on the valley topology, a rhombus-shaped beam splitter waveguide is designed to verify the valley-chirality selection rule above. Our numerical results entail that this topologically protected edge states still maintain robust transmission at sharp corners, thus providing a feasible idea for valley photonic devices in the THz regime. [ABSTRACT FROM AUTHOR]

Altitude is one of the determinant factors that influence the spatial distribution of birds and their species richness. However, few investigations studied its influence on African bird communities over a wide gradient in North Africa. Considering this knowledge gap, 194 sampling points were carried out along altitudinal gradient (773 to 2595 m) in two adjacent mountainous valleys in the Central High Atlas of Beni Mellal in Morocco, Aït Bouguemmaz (AB), and Ahançal (OA). Each valley was divided into three altitudinal intervals (low, medium, and high zones). For each spatial subdivision, we studied the phenological cycle, in the sense that each valley underwent a four-season monitoring, during 2018 and 2019. The results showed 131 species in the study area in 43 families; both valleys had similar community richness, but they differed by the phenological status of their species. Indeed, the increase in altitude led to a decrease in bird species richness, while it does not show any correlation with abundance. In addition, richness and abundance increased during the high-productivity seasons (i.e., spring and summer). Although these results were expected, they provide an opportunity to compare these results with higher latitude communities in Europe and to better focus future large-scale investigations on the combined influence of latitude and altitude on birds. [ABSTRACT FROM AUTHOR]

The width of fluvial valley floors is a key parameter to quantifying the morphology of mountain regions. Valley floor width is relevant to diverse fields including sedimentology, fluvial geomorphology, and archaeology. The width of valleys has been argued to depend on climatic and tectonic conditions, on the hydraulics and hydrology of the river channel that forms the valley, and on sediment supply from valley walls. Here, we derive a physically based model that can be used to predict valley width and test it against three different datasets. The model applies to valleys that are carved by a river migrating laterally across the valley floor. We conceptualize river migration as a Poisson process, in which the river changes its direction stochastically at a mean rate determined by hydraulic boundary conditions. This approach yields a characteristic timescale for the river to cross the valley floor from one wall to the other. The valley width can then be determined by integrating the speed of migration over this timescale. For a laterally unconfined river that is not uplifting, the model predicts that the channel-belt width scales with river flow depth. Channel-belt width corresponds to the maximum width of a fluvial valley. We expand the model to include the effects of uplift and lateral sediment supply from valley walls. Both of these effects lead to a decrease in valley width in comparison to the maximum width. We identify a dimensionless number, termed the mobility–uplift number, which is the ratio between the lateral mobility of the river channel and uplift rate. The model predicts two limits: at high values of the mobility–uplift number, the valley evolves to the channel-belt width, whereas it corresponds to the channel width at low values. Between these limits, valley width is linked to the mobility–uplift number by a logarithmic function. As a consequence of the model, valley width increases with increasing drainage area, with a scaling exponent that typically has a value between 0.4 and 0.5, but can also be lower or higher. We compare the model to three independent datasets of valleys in experimental and natural uplifting landscapes and show that it closely predicts the first-order relationship between valley width and the mobility–uplift number. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has produced controversies, and its mode of concrete social existence is strongly assembled in multiple ways of world-making that mobilize particular human-non-human relations. This paper analyzes the ways in which the people of the Andean valleys of northwestern Argentina understand and live the pandemic, in the partial coexistence of ways of understanding the body, the person, and wellbeing. On the one hand, we identify the so-called traditional way of life, which implies a relational sociality; on the other hand, the Pentecostal way of life, which promotes an interpretative current under an apocalyptic key. In sum, we are interested in thinking about the coexistence and assembly between ways of living suffering and well-being in the context of the pandemic, associated with expanded and relational socialities and with ways of imagining and living the "end of the world" as a specific manifestation of the Pentecostal tradition. Thus, the article proposes to overcome the perspective of COVID-19 as a given and universal phenomenon that produces different interpretations or cultural fictions, and consider it as a component in a wide network of human and non-human agencies, forming a scenario of epistemic plurality. Resumen: La pandemia de COVID-19 ha producido controversias variadas y su modo de existencia social se encuentra fuertemente ensamblado en múltiples formas de hacer mundo que movilizan particulares relaciones entre humanos-no humanos. Este trabajo analiza los modos en que la gente de los valles andinos del noroeste argentino entiende y vive la pandemia, teniendo en cuenta las formas de entender el cuerpo, la persona y el bienestar. Considera tanto el modo de vida identificado como tradicional, que implica una socialidad relacional, y el del pentecostalismo, que fomenta una corriente interpretativa bajo una clave apocalíptica. En suma, se propone pensar la convivencia y ensamblaje entre formas de vivir el padecimiento y el bienestar en el contexto de la pandemia, asociados con socialidades ampliadas y relacionales y con modos de imaginar y vivir el "fin del mundo" como manifestación específica de la tradición pentecostal. De este modo, se entiende al COVID-19 más que como un fenómeno dado y universal que produce diferentes interpretaciones o ficciones culturales, como un componente en una red amplia de agenciamientos entre humanos y no humanos, conformando un escenario de pluralidad epistémica. [ABSTRACT FROM AUTHOR]

We extend two hypotheses based on studies of 1st- to 3rd-order Piedmont watersheds of southeastern Pennsylvania, USA, by collecting data in a larger 3rd- to 5th-order watershed nearby. One hypothesis posits that presettlement river corridors were dominated by wetlands, and the other suggests that river valleys were filled by millpond sedimentation following European settlement. Both hypotheses support new river restoration practices, so their generality is important to assess. Ten lithofacies indicate depositional environments, while pedostratigraphic criteria and 14C dating define presettlement and postsettlement stratigraphic units. Basal gravels similar to modern stream bed sediments represent presettlement channels with active bedload transport. Wedgeshaped gravel deposits resembling modern bars further document presettlement bedload transport by channelized flows. Extensive presettlement and postsettlement units of massive, organic-poor, fine-grained sediment formed when overbank flows inundated floodplains. Peat deposits, exposed at a single site (but absent elsewhere), represent a presettlement wetland. Decimeter-thick, discontinuous, massive carbonaceous fine-grained sediments occasionally overlie basal gravels; these may represent localized wetlands adjacent to presettlement channels or hydraulic backwater environments. Laminated sand and mud accumulated behind one 3-mhigh mill dam, but these millpond deposits are absent at other sites. Instead of being dominated by wetlands, presettlement river corridors are better described as a complex mosaic of riparian environments including older colluvial landforms, floodplains (some of which may have been seasonally inundated wetlands), primary (and possibly secondary) channels, and depending on geomorphic setting, either localized or valley-spanning wetlands. After European settlement, millponds were important locally, but their deposits represent a minor component of the stratigraphic record. [ABSTRACT FROM AUTHOR]

The Greenland Ice Sheet is a key contributor to contemporary global sea level rise, but its long-term history and response to episodes of warming in Earth's geological past remain uncertain. The terrain covered by the ice sheet comprises ∼ 79 % of Greenland and ∼ 1.1 % of the Earth's land surface and contains geomorphological records that may provide valuable insights into past ice-sheet behaviour. Here we use ice surface morphology and radio-echo sounding data to identify ice-covered valleys within the highlands of southern and eastern Greenland and use numerical ice-sheet modelling to constrain the climatological and glaciological conditions responsible for valley incision. Our mapping reveals intricate subglacial valley networks with morphologies that are indicative of substantial glacial modification of an inherited fluvial landscape, yet many of these valleys are presently situated beneath cold-based, slow-moving (i.e. non-erosive) ice. We use the morphology of the valleys and our simple ice-sheet model experiments to infer that incision likely occurred beneath erosive mountain valley glaciers during one or more phases of Greenland's glacial history when ice was restricted to the southern and eastern highlands and when Greenland's contribution to barystatic sea level was up to + 7 m relative to today. We infer that this valley incision primarily occurred prior to the growth of a continental-scale ice sheet, most likely during the late Miocene (ca. 7–5 Ma) and/or late Pliocene (ca. 3.6–2.6 Ma). Our findings therefore provide new data-based constraints on early Greenland Ice Sheet extent and dynamics that can serve as valuable boundary conditions in models of regional and global palaeoclimate during past warm periods that are important analogues for climate change in the 21st century and beyond. [ABSTRACT FROM AUTHOR]

The ERA5 climate reanalysis dataset plays an important role in applications such as monitoring and modeling climate system changes in polar regions, so the calibration of the reanalysis to ground observations is of great relevance. Here, we compare the 2 m air temperature time series of the ERA5 reanalysis and the near-surface bias-corrected reanalysis to the near-ground air temperature measured at 17 automatic weather stations (AWSs) in the McMurdo Dry Valleys, Antarctica. We find that the reanalysis data have biases that change with the season of the year and do not clearly correlate with elevation. Our results show that future work should rely on secondary observations to calibrate when using the ERA5 reanalysis in polar regions. [ABSTRACT FROM AUTHOR]

Wildlife must increasingly balance trade‐offs between the need to access important foods and the mortality risks associated with human‐dominated landscapes. Human disturbance can profoundly influence wildlife behavior, but managers know little about the relationship between disturbance–behavior dynamics and associated consequences for foraging. We address this gap by empirically investigating the consequences of human activity on a keystone predator–prey interaction in a region with limited but varied industrial disturbance. Using stable isotope data from 226 hair samples of grizzly bears (Ursus arctos horribilis) collected from 1995 to 2014 across 22 salmon‐bearing watersheds (88,000 km2) in British Columbia, Canada, we examined how human activity influenced their consumption of spawning salmon (Oncorhynchus spp.), a fitness‐related food. Accounting for the abundance of salmon and other foods, salmon consumption strongly decreased (up to 59% for females) with increasing human disturbance (as measured by the human footprint index) in riparian zones of salmon‐bearing rivers. Declines in salmon consumption occurred with disturbance even in watersheds with low footprints. In a region currently among the least influenced by industrial activity, intensification of disturbance in river valleys is predicted to increasingly decouple bears from salmon, possibly driving associated reductions in population productivity and provisioning of salmon nutrients to terrestrial ecosystems. Accordingly, we draw on our results to make landscape‐scale and access‐related management recommendations beyond current streamside protection buffers. This work illustrates the interaction between habitat modification and food security for wildlife, highlighting the potential for unacknowledged interactions and cumulative effects in increasingly modified landscapes. [ABSTRACT FROM AUTHOR]

UAV imagery offers great potential in determining precise environmental measurements. This study identifies and quantifies errors and their causes/sources between UAV imagery- and field-derived measurements of large wood (LW) and cross-sectional valley topography in several forested headwater stream valleys in the Ozark Highlands, Missouri. UAV imagery was collected at six sites following best practices for producing high resolution orthophotos and elevation models through Structure-from-Motion photogrammetry. Field-based measurements of LW were completed along 5 m wide valley cross-sections in which all LW > 1 m in length and 0.1 m in diameter were recorded. Topographic surveys were performed along the centerlines of the LW transects. The same assessments were performed using UAV imagery and ArcGIS. Our sites showed high (>= 0.85) R2 values between field and UAV-GIS topographic surveys. Differences between measurements of LW dimensions tended to be larger with R2 ranging from 0.42 to 0.88. Overall 78 percent of standing trees and 60 percent of LW pieces were identified in the UAV imagery. The main source of detection and measurement error was due to vegetation/canopy cover. This study furthers our understanding of the applications and limitations of UAV derived data for environmental assessments. [ABSTRACT FROM AUTHOR]

This article, titled "Guest Editors' Introduction to Special Issue on Water and Rivers in the South (Part 1)," explores the significance of water in the physical and cultural landscapes of the US South. The region is home to a diverse range of water forms and is a hotspot of freshwater biodiversity. However, human activities have had a significant impact on water systems, including the construction of dams, pollution, and the introduction of invasive species. The article also discusses ongoing efforts to restore and mitigate these impacts through river restoration projects. This is the first part of a two-part special issue on water and rivers in the South. [Extracted from the article]

This article discusses the challenges and processes involved in translating brain tumor classification research into clinical practice. It highlights the three peaks and two valleys that researchers encounter during this journey. The first valley is crossed more frequently and involves pathologists working on translational work. The second valley is crossed less often and requires teams to develop consensus-driven approaches and resources for implementation. The article also discusses the role of various organizations, such as the World Health Organization (WHO), the Consortium to Implement Molecular and Practical Approaches to CNS Tumor Taxonomy (cIMPACT), national societies, and the International Collaboration on Cancer Reporting (ICCR), in standardizing tumor diagnosis and reporting. The author emphasizes the importance of considering the impact on patients, understanding the complexity of biology, and recognizing that guidelines are a work in progress. The article concludes by urging future brain tumor experts to work collectively and strive for successful national and international implementation. [Extracted from the article]

• This patient testimonial illustrates the potential of physical training in congenital myopathies. • It also shows the importance of intrinsic motivation for training, and how this can evolve in adolescence. • Changes in physical activity and training can influence the outcome measures in trials. [ABSTRACT FROM AUTHOR]

The modulation of the valley structure in two-dimensional valley materials is vital in the field of valleytronics. The multiferroicity provides possibility for multiple modulations of the valley, including the magnetic and electric means. Based on the first-principle calculations, we study the valley properties and associated manipulations of multiferroic Co 2 CF 2 monolayers with different stacking patterns. Our calculations show that the Co 2 CF 2 monolayer in the H′ phase is a ferrovalley material, with sizable valley splittings. By rotating the magnetization direction, the valley splittings can be tuned for both the magnitude and sign. The process of the ferroelectric switching can also change the magnitude of the valley splittings. In addition, a metastable T′ phase exhibits valley splittings as well, of which the magnitude and sign can be simultaneously controlled by applied magnetic field and ferroelectric switching. These findings offer a practical way for realizing highly tunable valleys by multiferroic couplings. [ABSTRACT FROM AUTHOR]

The exploration of valley-related physics is essential to the development and refinement of valleytronics. Here, a paradigm called chiral breathing-valley locking (CBVL) is proposed, in which two chiral "breathing" phases are completely locked to their valley indexes. Utilizing first-principles calculations, a two-dimensional (2D) kagome lattice with large spontaneous valley polarization (VP), namely, monolayer Ta3I8, is proposed to realize CBVL. There are two breathing phases with chiral symmetry in Ta3I8, and they can change to each other under some conditions. The valley indexes change between "−K" and "K" along the breathing of the two chiral symmetric phases, so CBVL can be obtained. Remarkably, the VP is up to 199.7 meV, so CBVL can cause the obvious switching of the anomalous valley Hall effect (AVHE). Additionally, a 2D Janus Kagome structure TaI4X4 is constructed to confirm experimentally the feasibility of electric field modulation on the CBVL. The built-in electric field and the breathing mode can mutually influence each other in TaI4X4, which provides a synergistic regulation of the AVHE. Our findings broaden the horizon for exploring AVHE materials and provide a platform for future valleytronic applications. [ABSTRACT FROM AUTHOR]

Satellite survey is widely used for archaeological site discovery, but the efficacy of the method has received little systematic investigation. In this analysis, twelve study participants of different experience levels performed an unstructured remote survey of 197 km2 in the Sama and Moquegua valleys of south central Peru where previous pedestrian surveys recorded 546 archaeological sites. Results indicate an average site discovery rate of 9.3% (0–18%, 95% range). The most experienced participants detect up to 20% (17–22%) of known archaeological sites. These detection rates can be used to derive reliable site frequency estimates on the Andean coast, which can be used in planning and budgeting for field efforts and estimating demographic patterns at large spatial scales that are difficult to achieve through pedestrian survey. More generally, this analysis offers a method for deriving correction terms specific to other parts of the world. Additionally, the results can serve as a baseline for evaluating the effectiveness of emerging artificial intelligence routines for archaeological site detection. [ABSTRACT FROM AUTHOR]

Simple Summary: A study of digger wasps was carried out along a gradient of forest stands in river valleys in northern Poland. One hundred and thirty six species were recorded, representing over half of all Polish digger wasp species. These included 30 species on the Red List of Endangered Animals in Poland. Some additional information on prey species and food plants was also collected. Natural succession to woodland was associated with a change in species composition, but principally with a decline in species richness and diversity. This study of digger wasps (Hymenoptera: Spheciformes) was carried out in the cultural landscape of the Drwęca, Lower Vistula, and Warta river valleys in northern Poland during 2011–2013. The study was undertaken on sites representing a succession gradient from dry grasslands to high levels of tree cover which we hypothesised would influence the structure of digger wasp communities. During our research additional information on flower use, insect prey, and phenology was also recorded and is reported here, revealing dependencies between woodland cover and both the prey and nesting types of digger wasps. A total of 136 species were recorded, i.e., nearly 56% of all Spheciformes species recorded from Poland. Among the species collected, 30 were on the Red List of Threatened Animals in Poland. Most endangered species were recorded in psammophilous grasslands, which are open habitats, and the least in mesic sites. These results significantly update the known distribution of the digger wasp in northern Poland. Knowledge on the biology of digger wasps in Poland is also supplemented by information on the feeding of larvae of 14 species and information on food plants visited by imago digger wasps. The results of our research confirm the correlations between the increase in forest cover and the number of digger wasp species. [ABSTRACT FROM AUTHOR]

This study investigates the effects of lakes in mountainous terrain on the evolution of supercell thunderstorms. With a newly developed radar-based, mesocyclone-detection algorithm, a recent study has characterized the occurrence and evolution of supercell thunderstorms in the Swiss Alpine region. That study highlights the influence of orography on both storm intensity and occurrence frequency. To disentangle the different influential factors, an idealized modeling framework is established here using the mesoscale model CM1. The modeling scenarios are based on a high-CAPE environment with unidirectional shear, where a warm bubble serves to initiate the convection. Mimicking the environment of the southern Prealps in central Europe, scenarios with a high mountain ridge, valleys, and lakes are explored. The effect on the supercells of the slopes, high-altitude terrain, and moisture sources emphasizes the highly localized nature of terrain effects, leading to a heterogeneous intensity life cycle with transitory enhancement and weakening of the supercell. The dynamic and thermodynamic impact of mountain valleys with lakes increases the range of atmospheric conditions that supports supercellular development through horizontal vorticity production, increased storm relative helicity, and higher moisture content. This influence results in a systematic location dependence of the frequency, intensity, and lifetime of supercells, as also found in observations. [ABSTRACT FROM AUTHOR]

In this study, we present new records of the extinct South American proboscidean Notiomastodon platensis from three new fossiliferous sites in the riverbed of Cauca River, in the department of Valle del Cauca, Colombia. The fossil specimens were found in late Pleistocene deposits and include immature to senile Notiomastodon platensis individuals, comprising abundant dental and post-cranial materials. A review of the geographic distribution of the Notiomastodon platensis records in Colombia suggests that this giant mammal used the inter-Andean valleys as migratory corridors, possibly due to the presence of more suitable environmental conditions (lower temperatures and dry-forest) and energy-saving terrains, avoiding more prominent Andean hills. In addition, the Cauca Valley deposits stand out as having palaeontological significance to the comprehension of the late Pleistocene of the western region of South America. [ABSTRACT FROM AUTHOR]

Context. TOI-732 is an M dwarf hosting two transiting planets that are located on the two opposite sides of the radius valley. Inferring a reliable demographics for this type of systems is key to understanding their formation and evolution mechanisms. Aims. By doubling the number of available space-based observations and increasing the number of radial velocity (RV) measurements, we aim at refining the parameters of TOI-732 b and c. We also use the results to study the slope of the radius valley and the density valley for a well-characterised sample of M-dwarf exoplanets. Methods. We performed a global Markov chain Monte Carlo analysis by jointly modelling ground-based light curves and CHEOPS and TESS observations, along with RV time series both taken from the literature and obtained with the MAROON-X spectrograph. The slopes of the M-dwarf valleys were quantified via a support vector machine (SVM) procedure. Results. TOI-732b is an ultrashort-period planet (P = 0.76837931-0.00000042+0.0000039 days) with a radius Rb = 1.325-0.058+0.057R⊕, a mass Mb = 2.46 ± 0.19 M⊕, and thus a mean density ρb = 5.8-0.8+1.0 g cm-3, while the outer planet at P = 12.252284 ± 0.000013 days has Rc = 2.39-0.11+0.10R⊕, Mc = 8.04-0.48+0.50M⊕, and thus ρc = 3.24-0.43+0.55 g cm-3. Even with respect to the most recently reported values, this work yields uncertainties on the transit depths and on the RV semi-amplitudes that are smaller up to a factor of ~1.6 and ~2.4 for TOI-732 b and c, respectively. Our calculations for the interior structure and the location of the planets in the mass-radius diagram lead us to classify TOI-732 b as a super-Earth and TOI-732 c as a mini-Neptune. Following the SVM approach, we quantified d log Rp,valley / d logP = -0.065-0.013+0.024, which is flatter than for Sun-like stars. In line with former analyses, we note that the radius valley for M-dwarf planets is more densely populated, and we further quantify the slope of the density valley as d log ρ^valley / d log P = -0.02-0.04+0.12. Conclusions. Compared to FGK stars, the weaker dependence of the position of the radius valley on the orbital period might indicate that the formation shapes the radius valley around M dwarfs more strongly than the evolution mechanisms. [ABSTRACT FROM AUTHOR]

Shelf-incised valleys, carved by ancient rivers and estuaries during periods of continental shelf exposure, were primarily shaped by base-level fluctuations in the Quaternary. These geological features are prevalent in the western South Atlantic shelf but often go unnoticed as key indicators of the region's evolution. This research unveils the outcomes of a comprehensive investigation that combined sub-bottom profiling (SBP) surveys, historical bathymetric data, and the application of Geographic Information System (GIS) tools to extract drainage patterns within the Santos Basin, a significant sedimentary basin in Brazil.The study provides an unprecedented overview of the interconnected network of the ancient drainage system across the continental shelf, totalizing 91 thalwegs associated with 80 incised valleys in the study area, ranging in length from 250 m to 148 km. This connection between the mapped incised valleys and the upper slope evolved through three distinct phases during the Late Pleistocene. The first phase (Phase A) was characterized by the formation and subsequent destruction of incised valleys, driven by high-frequency sea-level oscillations during MIS5. The second phase (Phase B, with subphases B1 and B2) witnessed the construction of incised valleys during a period of forced regression at MIS4 and MIS3. The final phase (Phase C) marked the establishment of fully developed valleys, connecting them to upper slope canyons during the Last Glacial Maximum (LGM). The correlation of these sea-level changes with the presence of underfilled incised valleys in the Santos Basin shelf represents a significant breakthrough in understanding the geological history of the western South Atlantic shelf. These valleys typically eroded until reaching depths near the transient base level, offering a valuable glimpse into the geological chronicles of sea-level fluctuations over time. [ABSTRACT FROM AUTHOR]

Three Parallel Rivers is one of the world's biodiversity hotspots. However, the research on myxomycetes diversity is scarce in this area. Random sampling was used to investigate myxomycetes' diversity and distribution characteristics in this area. One hundred and seventeen species, including three varieties, were obtained, belonging to 28 genera, nine families, and six orders, with Arcyria cinerea and Physarum viride being the dominant species. Moreover, four species and one variety were first reported in China. Twenty-six species and one variety were first reported in Yunnan Province. The species' most commonly utilized substrate for fruiting bodies was decaying wood, and Cribraria was the dominant genus. The species diversity was most abundant in mixed broadleaf-conifer forests. Species similarity between coniferous and broad-leaved forests was much higher than the pairwise comparison of other forest types. NMDS analysis shows that substrate and forest types had insignificant effects on myxomycetes communities, while river valley had a significant effect. The myxomycetes community similarity between river valleys is unrelated to geographical proximity. [ABSTRACT FROM AUTHOR]

The Byzantine author Agathias (sixth century CE) states that the Alamanni are not yet Christians but venerate nature instead. In scholarship, this passage is used as evidence of 'nature worship' in the late paganism of this Germanic tribe. However, in-depth analysis suggests a more nuanced picture. On the one hand, nature worship is a classical topos for the religion of barbaric peoples. On the other hand, archaeological and other textual sources give the impression that the Alamanni of Agathias' day may already have been partially Christianized and might, in fact, have been in a phase of syncretism leaning toward Christianity rather than being 'staunchly heathen', as they are often portrayed. Agathias' claim of a pagan Alamannic nature worship therefore should be seen as a stereotypical projection by this Byzantine author rather than a reflection of genuine Alamannic religious attitudes. [ABSTRACT FROM AUTHOR]

Landslides often occur in V-shaped valleys exhibiting strong river incisions and large elevation differences between the riverbed and surrounding mountains. This study expounded upon the topographical and flow conditions of typical landslide dam sites through field investigations and data collection and established a small-scale physical model for experimental research. The formation conditions of landslide dams, an important part of the long-term management of such events, were studied. Simultaneously, the experiments verified a series of engineering measures proposed based on calculus theory and implementation principles according to their experimental disposal effects to mitigate short-term flood risks. Results showed that the dam formation is mainly related to topographic characteristics, upstream flow, and dam compositions. Specifically, steep V-shaped valleys should be considered when establishing physical models as they provide great conditions for landslide mass blocking the river completely. In addition, for earth dams, the effects of the position and direction of excavated diversion channels were compared; it showed that when there are multiple passes on the dam crest, priority should be given to lateral excavation of channels from the pass to restrict the lateral development process. The dam-break flow direction should better be orthogonal rather than be parallel to the river bend, which can reduce peak flow discharge by natural energy dissipation. For earth and rockfill dams with wide particle distributions, piles and flexible nets were instead utilized to coarsen the dam breach and reduce peak flow discharge. Finally, applicable values and research significance were summarized based on the obtained results. This research enriches studies of mountain disaster management and provides guidance for on-site emergency response. [ABSTRACT FROM AUTHOR]

Jump functions are the most-studied non-unimodal benchmark in the theory of randomized search heuristics, in particular, evolutionary algorithms (EAs). They have significantly improved our understanding of how EAs escape from local optima. However, their particular structure—to leave the local optimum one can only jump directly to the global optimum—raises the question of how representative such results are. For this reason, we propose an extended class J U M P k , δ of jump functions that contain a valley of low fitness of width δ starting at distance k from the global optimum. We prove that several previous results extend to this more general class: for all k ≤ n 1 / 3 ln n and δ < k , the optimal mutation rate for the (1 + 1) EA is δ n , and the fast (1 + 1) EA runs faster than the classical (1 + 1) EA by a factor super-exponential in δ . However, we also observe that some known results do not generalize: the randomized local search algorithm with stagnation detection, which is faster than the fast (1 + 1) EA by a factor polynomial in k on J U M P k , is slower by a factor polynomial in n on some J U M P k , δ instances. Computationally, the new class allows experiments with wider fitness valleys, especially when they lie further away from the global optimum. [ABSTRACT FROM AUTHOR]

Studies of the paleogeographical properties of the Ubsunur Basin located on the territory of northwestern Mongolia and southern Tuva are based on the discovery of buried ice veins under Aeolian sediments in the region of Lake Khar-Nur in the eastern mountainous frame of the Great Lakes Basin of Western Mongolia. Satellite images have shown outlines of fields along the periphery of the sand deposits, the natural irrigation of which, in our opinion, was due to the melting of the abovementioned ice. Deposits similar to glacial ones have been found in the river valleys of the northern mountainous framing of the Ubsunur Basin, in its foothill part, suggesting the presence of Pleistocene glaciers extending into its flat plains. It is also assumed on this basis that, similarly to Lake Khar-Nur, the peculiar sandy massifs located in the basin could preserve relic zones of permafrost, the thawing of which contributed to the moistening of local landscapes. Such humidification zones have been seen on satellite images. There are no glacial deposits in this territory in geological legends. At this stage of research, we confirm the presence in the past of thin glaciers in the study site, caused by mountain-forming processes, and the eruption of Quaternary volcanoes on the territory of Tuva and Mongolia. Tectonic processes contributed to the damming of the Tes Khem River, the main waterway flowing along the northern mountain rim of the basin, the formation of dammed lakes, and their subsequent descent. Extended original sandy massifs located in the basin within the Agardag mountain range, previously considered fluvioglacial deposits, are a result of the descent of dammed lakes. [ABSTRACT FROM AUTHOR]

Nitrogen (N) fixation is a fundamental mechanism by which N enters streams. Yet, because of modern N saturation, it is difficult to study the importance of N-fixation to stream nutrient budgets. Here, we utilized relatively simple and pristine McMurdo Dry Valley streams to investigate the role of N-fixing Nostoc abundance, streamwater dissolved inorganic N (DIN) concentration, and distance from the source glacier in regulating the elemental and isotopic composition of three microbial mat types (black, orange, and green) at the landscape scale. We found Nostoc-based black mats were the most enriched in δ15N, and δ15N signatures of mats increased where Nostoc was abundant, but did not surpass the atmospheric standard (δ15N ≈ 0‰). Furthermore, green and orange mat δ15N signatures became more depleted with increasing DIN, indicating that mats utilize glacial meltwater-sourced N when available. The distance from the source glacier explained limited variability in mat δ15N across sites, indicating the influence of individual stream characteristics on N spiraling. To further explore longitudinal N spiraling processes generating observed δ15Ν patterns, we developed a simple steady-state mathematical model. Analysis of plausible scenarios with this model confirmed that streams both have the capacity to remove allochthonous DIN over the plausible range of inputs, and that internal N sources are required to account for δ15N signatures and observed DIN concentrations at stream outlets. Collectively, these data and modeling results demonstrate that N-fixation exerts substantial influence within and across these streams, and is presumably dependent upon interconnected organic matter reserves, mineralization rates, and geomorphology. [ABSTRACT FROM AUTHOR]

The article represents a part of the researches done for the doctoral thesis, which aims at the knowledge of the vegetation in the basin of Pesceana river, Vâlcea county. This offers actual data regarding the types of habitats identified in the studied area and their typical vegetation. The phytocoenological observations developed between 2021-2023 in the basin of the Pesceana river permitted the identification of nine types of habitats of conservative interest, as: 91M0 – Pannonian-Balkanic turkey oak-sessile oak forests; 9130 – Asperulo-Fagetum beech forests; 91Y0 – Dacian oak - hornbeam forests; 91E0* - * Alluvial forests with Alnus glutinosa and Fraxinus excelsior (Alno-Padion, Alnion incanae, Salicion albae); 9170 – Galio-Carpinetum oak-hornbeam forests; 6440 – Alluvial meadows of river valleys of the Cnidion dubii; 6430 – Hydrophilous tall herb fringe communities of plains and of the montane to alpine levels; 6520 – Mountain hay meadows; 6240* - * Sub-Pannonic steppe grasslands.The article is focused on the description of four types of forest habitats, respectively the habitats of community interest 91M0; 9130; 91Y0 și 91E0*. The description of the habitats is followed by an analysis of the similarity on the account of the surveys done for every type of forest habitat. Also, the physical and chemical particularities of the soils in theses habitats identified at the studied area are highlighted The aim of the actual article is to identify, inventory and highlight the particularities that the forest habitats present in the studied area and the plant community typical for these habitats. [ABSTRACT FROM AUTHOR]

In 2019, the Gansu Provincial Institute of Cultural Relics and Archaeology and other institutions excavated the tomb of Murong Zhi, the King Xi of Tuyuhun, located at Chashan Village, Qilian Town, Tianzhu County. A comprehensive archaeological survey of the Binggou and Dashui river valleys in Qilian Town in 2020 revealed the existence of 23 Tuyuhun royal tombs across four areas. Three tombs at the Changling-Machangtan area in Qilian Town, excavated in 2021, are identified as a probable section of the Tuyuhun Pengzi clan's family cemetery during the Tang dynasty. Through ongoing archaeological work, three large mausoleum areas have been confirmed in Wuwei's Nanshan district: Yanghui Valley, Great Khan Mausoleum, and Baiyang Mountain. The tomb distribution is characterized by being widely dispersed but mutually connected. Excavations also confirm that Tuyuhun tombs were constructed without aboveground mounds. Additionally, rare Tang artifacts were discovered. [ABSTRACT FROM AUTHOR]

In this paper we develop a stochastic simulation algorithm for electron transport in a DA-pHEMT heterostructure. Mathematical formulation of the problem of electron gas transport in the heterostructure in the form of a coupled system of Poisson, Schrödinger and kinetic Boltzmann equations is given. A Monte Carlo model of electron transport in DA-pHEMT heterostructures which accounts for multivalley parabolic band structure, as well as relevant formulas for calculating electron scattering rates and scattering phase functions on polar optical, intervalley phonons and on impurities are developed. The results of a computational experiment involving the solution of the system of Poisson–Schrödinger–Boltzmann equations for the AlGaAs/GaAs/InGaAs/GaAs/AlGaAs heterostructure are presented. The distribution of electrons by energy subband in the main and satellite valleys and the field dependences of the electron drift velocity in each valley are calculated. It was discovered that there is no spatial transfer of electrons into wide-gap AlGaAs layers due to high barriers created by modulated-doped impurities. A comparative analysis of the electron drift velocities in the studied DA-pHEMT heterostructures and in the unstrained layer of the InGaAs is given. [ABSTRACT FROM AUTHOR]

The Southeastern Coastal Hinterland geomorphic province of South Africa is dissected by deep valleys created by tectonic uplift in the early Miocene and late Miocene/early Pliocene. We hypothesised that seedlings of Vachellia nilotica, V. tortilis and V. karroo grown from seeds from different valleys would differ in growth and spinescence because of geographical separation. Ninety seedlings (30 per species) were grown for 3 months in uniform conditions in a greenhouse. Mean height of V. nilotica and V. tortilis seedlings was greatest for the Phongolo populations and lowest for the Thukela populations. Maximum stem diameter of both species was attained by individuals from the Phongolo population. Mean spine dry mass of V. nilotica seedlings was greatest for the Phongolo population, suggesting a growth‐defence trade‐off, but did not differ for V. tortilis. Results suggested that Phongolo populations of V. nilotica and V. tortilis may be characterised by morphotypes clearly distinct from those in the other valleys. Unclear and inconsistent results for V. karroo in this study suggested subtly different morphotypes occur in each valley. We propose that distinct Phongolo morphotypes of V. nilotica and V. tortilis are explained as evolutionary adaptations to moderate fire and high browsing pressure compared to populations South of Phongolo. [ABSTRACT FROM AUTHOR]

This contribution analyses the structural architecture and tectono-metamorphic evolution of Briançonnais units in the southern French-Italian Western Alps. The studied area extends from a virtually non-metamorphic area adjacent to the Helvetic-Dauphinois External Domain in the west to the Monviso-Queyras ocean-derived units in the east, where metamorphism increases up to eclogite-facies. Mapping at the scale 1:10.000 of a mountainous part of the Ubaye-Maira transect was performed, which portrays in detail the Briançonnais units over ~ 100 km2. The lithologies include meta-andesite, meta-siliciclastics, marbles, turbiditic calcschists and flysch whose age spans from Late Carboniferous to Eocene. Metamorphism is low-grade greenschist-facies in the west but reaches the blueschist-facies to the east. Structures related to four phases of deformation are identified. The first two generations of structures (D1–D2), related to the original top-to-the-west nappe stacking, are associated with conditions close to the peak of Alpine metamorphism. Previous tectonic surfaces are transposed by the dominant deformation structures (D3), developed under retrograde/decompression conditions. This D3 corresponds to a backfolding and back-thrusting event with a top-to-the-E transport. A fourth phase (D4) developed during late low-grade metamorphic conditions and deforms the previous surfaces by locally developing a crenulation cleavage, followed by brittle tectonics. An updated metamorphic map is presented, backed on published estimates and new thermometric data obtained by Raman Spectroscopy of Carbonaceous Material (RSCM). The TRSCM values range from ~ 295 °C to > 350 °C, moving from the most external Briançonnais unit to the internal Queyras "Schistes Lustrés" units. Suspected Upper Cretaceous palaeofaults have been documented, allowing us to group the classic Aiguille de Mary and Ceillac (sub-) units into a single tectonic unit, here referred to as Maurin unit. The palaeogeographical reconstruction of the evolution of the studied transect highlights the importance of the Marinet and Maurin axial units in the feeding of the Late Cretaceous-Eocene breccias deposited on the more internal Acceglio-type units. [ABSTRACT FROM AUTHOR]

Continental shelves encompass gently sloped seascapes that are highly productive and intensively exploited for natural resources. Islands, reefs and other emergent or quasi-emergent features punctuate these shallow (<100 m) seascapes and are well known drivers of increased biomass and biodiversity, as well as predictors of fishing and other human uses. On the other hand, relict mesoscale geomorphological features that do not represent navigation hazards, such as incised valleys (IVs), remain poorly charted. Consequently, their role in biophysical processes remains poorly assessed and sampled. Incised valleys are common within rhodolith beds (RBs), the most extensive benthic habitat along the tropical and subtropical portions of the mid and outer Brazilian shelf. Here, we report on a multi-proxy assessment carried out in a tropical-subtropical transition region (~20°S) off Eastern Brazil, contrasting physicochemical and biological variables in IVs and adjacent RBs. Valleys interfere in near bottom circulation and function as conduits for water and propagules from the slope up to the mid shelf. In addition, they provide a stable and structurally complex habitat for black corals and gorgonians that usually occur in deeper water, contrasting sharply with the algae-dominated RB. Fish richness, abundance and biomass were also higher in the IVs, with small planktivores and large-bodied, commercially important species (e.g. groupers, snappers and grunts) presenting smaller abundances or being absent from RBs. Overall, IVs are unique and vulnerable habitats that sustain diverse assemblages and important ecosystem processes. As new IVs are detected by remote sensing or bathymetric surveys, they can be incorporated into regional marine management plans as conservation targets and priority sites for detailed in situ surveys. [ABSTRACT FROM AUTHOR]

The problem of differentiation and correlation of the Upper Quaternary sediments comprising the valleys of the main rivers in Western Siberia (primarily the Ob and Yenisei) was actively discussed in the second half of the 20th century and has not been solved conclusively at the end of the first quarter of the 21st century. Traditionally, the regional Quaternary history of the river valleys was considered as the "terrace staircase" paradigm, under which, in the Neogene–Quaternary, alluvial terraces formed sequentially from the older upper to the younger lower ones. Neotectonics, paleoclimate dynamics that changed the water abundance of the rivers, sea transgressions and regressions that affected the erosion base level, and frequent blocking of river valleys by northern glaciers leading to the formation of dammed lakes and the periglacial alluvium in the extraglacial zone were considered to be the factors that controlled their formation. However, the heights, age, and even the number of terraces differ significantly not only in the published works, but also on the official maps of Quaternary deposits. Significant data have been accumulated that contradict the concepts about a vertical staircase of successively downcut cycloclimatic terraces and periglacial alluvium facies that replaced the glacier-dammed northern lakes in the southern part of Western Siberia. A refined concept of the sediment structure in the Upper Neopleistocene in the main valleys of this region that takes into account the data on three glacier outburst floods from intermountain basins to the plain has been formulated and substantiated. The intense erosional and accumulative activity has continued to be underestimated. [ABSTRACT FROM AUTHOR]

Iraq is located in the extreme northeastern part of the Arabian Plate, which is in collision with the Iranian (Eurasian) Plate. The collision, which is still ongoing has created tens of folds some of which exhibit different types of faults. The exerted compressional forces are believed to be decreasing southwestwards as being far from the collision area (Suture Zone). Accordingly, all the existing tectonic and geological maps compiled by different authors and all the existing published articles, reports and books have considered two main tectonic domains in Iraq. The Stable Shelf and Unstable Shelf or Inner Platform and Outer Platform. The contact between these two main divisions follows almost the Euphrates River; towards the west of the river is the tectonically Stable area and towards the east and north is the tectonically Unstable area, which means the presence of different structural forms. In the current study, we have recognized tens of different Neotectonic evidence in the Stable part indicating that the area is tectonically not stable. Among those indications are abandoned valleys, development of sinkholes along certain lineaments, bending of valleys in right angles, and development of nick-points in valleys along certain lineaments. [ABSTRACT FROM AUTHOR]

Leaching of excess nitrogen (N) to groundwater in fertilized landscapes can overwhelm natural biogeochemical processes and cause long-term eutrophication of aquatic systems. We investigated N fate and transport from an intensively managed short-rotation woody crop (Pinus taeda) plantation through the riparian zone of an intermittent, low-gradient blackwater stream. Fertilization of the P. taeda plantation on the uplands resulted in contamination of groundwater with nitrate concentrations between 0.9 and 1.9 mg N L−1. No corresponding increase in nitrate was observed in stream water or shallow groundwater in the riparian zone. Groundwater travel-time modeling predicted that N from near-stream, upland plantation areas should have reached streams during the monitoring period. Two years of measuring N species in well water in contrasting landscape positions (within the plantation, swale, riparian edge, forested hillslope, and valley), indicated rapid nitrate transformation and denitrification within the forested wetland valleys. Denitrification in the shallow groundwater system within the toeslopes and the riparian zone was estimated to have removed > 90% of nitrate. These results highlight the importance of riparian zones as pathways for the removal of N and for controlling downstream N loads. [ABSTRACT FROM AUTHOR]

This paper presents a finite volume-based simulation study on the effect of the fin valley's number on the thermal performance of a bus duct conductor. A numerical model that closely mimics the experimental setup was developed using ANSYS FLUENT. The experimental data were used as a benchmark and followed the IEC 61439-1/2 standards. Five fin valley numbers were considered: s1=2, s2=3, s3=4, s4=5 and s5=6. It was determined that the average surface temperature decreased as the number of fin valleys increased. From the analysis, it was observed that as the number of fin valleys increased, convection heat transfer improved as a consequence of enhanced surface Nusselt number. The best number of fin valleys was s5=6, exhibiting superior thermal performance over a lower number of fin valleys. This study is expected to provide a better understanding of the fin valley's effects on the thermal performance of a bus duct conductor's casing. [ABSTRACT FROM AUTHOR]

The surface of the Kulunda Plain is dissected by a system of ancient wide valleys, former runoff hollows with a very small slope (less than 1°). Rivers flow through these weakly expressed valleys, redistributing soluble salts throughout the territory. The regime of these rivers is characterized by a high flood wave and low (up to complete drying) runoff in the summer. The purpose of this work is to study the ion-salt system of soils of ancient runoff hollows of the Kulunda Plain, their groundwater and river water flows in order to identify modern soil salinization processes. During floods, river water recharges nearby groundwater influencing its chemical composition. Studies of three key sites in the valleys of the Bagan (Novosibirsk oblast), Burla, and Kulunda (Altai region) rivers were conducted in 2021–2022. Groundwaters of various degrees of salinity (from 3.4 to 63.0 g/L) occur close to the surface (2–5 m), which determines the wide distribution of saline hydromorphic soils in the study area. Differences in the salt status of soils, groundwater, and river water in different valleys are considered. The degree of soil salinity depends on the soil texture. The high content of physical clay (<0.01 mm) particles contributes to the rise of salts with groundwater and their accumulation in the soil profile. A high content of exchangeable sodium in the soil adsorption complex (more than 3–5 cmol(c)/kg), the predominance of soluble sodium salts in the soil solution with its low mineralization, as well as the alkaline reaction of the soil medium are indicative of the development of solonetzic features in the studied soils. [ABSTRACT FROM AUTHOR]

In recent years, valleytronics researches based on 2D semiconducting transition metal dichalcogenides have attracted considerable attention. On the one hand, strong spin–orbit interaction allows the presence of spin–valley coupling in this system, which provides spin addressable valley degrees of freedom for information storage and processing. On the other hand, large exciton binding energy up to hundreds of meV enables excitons to be stable carriers of valley information. Valley polarization, marked by an imbalanced exciton population in two inequivalent valleys (+ K and − K), is the core of valleytronics as it can be utilized to store binary information. Motivated by the potential applications, we present a thorough overview of the recent advancements in the generation, relaxation, manipulation, and transport of the valley polarization in nonmagnetic transition metal dichalcogenide layered semiconductors. We also discuss the development of valleytronic devices and future challenges in this field. [ABSTRACT FROM AUTHOR]