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• Twilight phenomena occurs in the thermosphere. • An equation has been derived to calculate diurnal atmospheric height using the twilight images analysis. • The diurnal atmosphere has estimated height ∼304 km above sea level. • Lower wind speeds and temperatures resulted in a higher thickness of diurnal atmosphere. • Higher relative humidity and dew point resulted in a higher thickness of diurnal atmosphere. • The first appearance of dawn twilight is at dip = ∼15°. An equation has been derived through which the height of the diurnal atmospheric layer (lower atmosphere) can be calculated using ground base twilight image analysis. This equation relies on the angular altitude of the twilight with the dip at that moment. Based on the images, it was found that true twilight of dawn occurs at a dip of 14.90° ± 0.17° as detected by the camera or ∼15° by considering the elevation above sea level (while it may be delayed to ∼14.7–14° with the naked eye), which is accompanied by an average twilight angular altitude of 2.66° ± 0.23°. From these values, the twilight height is estimated to be 303.80 ± 5.69 km above sea level. It is shown that the twilight region is the peak zone of the thermosphere. Its height also varies with time according to changes in various atmospheric parameters. Lower wind speeds, higher relative humidity, higher dew point, and lower temperatures resulted in a higher altitudinal angle of the atmosphere and consequently a greater diurnal atmospheric layer's thickness. Image analysis shows that the thermosphere always has a maximum value of light brightness during the night even before the appearance of twilight. Additionally, It defined the light source, shapes, and stages of twilights that detected by images. This implies that sky image analysis is an inexpensive method for understanding the properties and various parameters of the atmosphere. [ABSTRACT FROM AUTHOR]

The phenomenon of twilight has been stipulated as naturally dependent on the variables of solar depression, aerosol concentration and ozone composition. The unique color spectrum of twilight is attributed by ozone layer and aerosol, whereas its brightness is heavily relying on the altitude of sun below horizon. While all the natural dependence is being researched extensively, the impact of light pollution on the brightness of the twilight is not being explored thoroughly. The objective of this study is to find out the alteration of light pollution towards the natural behavior of twilight sky brightness. Total of 84 data of twilight brightness was collected from 2014 until 2022 using Sky Quality Meter, and the specific location with profile classified as urban, suburban and pristine is investigated to study the impact of light pollution on twilight brightness. The result demonstrates that the stability of twilight brightness, which naturally factored by solar depression within the range of 18°, discovered to be heavy influenced by the zenith light pollution of the location sky, as evidenced by location that has zenith pollution of 17.11, 19.77, and 21.39, has horizontal twilight brightness of 14.84, 19.55 and 21.2 and solar depression during brightness stability at 11.5°, 15.67° and 17.49°. [ABSTRACT FROM AUTHOR]

This study aims to identify the manifestations of masculinity portrayed by the main characters in the Twilight Saga novel series and to examine the appraisal system utilized to articulate masculinity and its subsequent translation. This research employed qualitative descriptive research. This research was oriented towards translation products. Data sources, including documents and informants, were selected through purposive sampling. The novels Twilight Saga Series, along with their translated versions, served as primary documents. Informants comprised experts in translation and linguistics. Linguistic and translation data form the basis of the research, encompassing shifts in translation and expressions of masculinity alongside evaluation schemes. Data analysis employed domain, taxonomy, component, and cultural theme analyses. The research findings revealed the presence of both invoked and inscribed expressions of masculinity. Five distinct types of masculinity emerge: sexual, intellectual, emotional, physical, and interpersonal. Graduation and attitude constitute the appraisal system for these expressions, with judgment being the most prevalent attitude type in Edward and Jacob's manifestations of masculinity. The research shows two shifts in masculinity type and appraisal systems. While both characters exhibit strong masculinity, the author provides more detailed descriptions of Edward's masculinity than Jacob's. Edward Cullen's masculinity is heavily influenced by his family background, particularly emphasizing physicality over other forms of masculinity. The study identifies data shifts, encompassing changes in masculinity type and appraisal system. Suggestions for future research include exploring translation methods and ideologies not addressed in this study and investigating prototype translation models for translating masculinity. [ABSTRACT FROM AUTHOR]

The light climate at high latitudes, in particular the extended twilight of winter and the reduced diel variation in light level in midsummer and midwinter, potentially constrains visual function and the synchronisation of temporal organisation in polar species. In this paper, we describe the temporal pattern and variation in the spectral composition and brightness of skylight (daylight, twilight, moonlight, starlight, airglow and aurorae) at high latitudes and review photoreception of reindeer/caribou (Rangifer tarandus; ‘Rangifer’) which is one of the few polar resident species for which data are available. Experimental data indicate that the rods of Rangifer may be stimulated by levels of ambient light lower than those occurring during astronomical twilight (solar angle <−18°). Several features of the eyes of Rangifer contribute to their visual capability under extended twilight. These include transmission of UV through the optical media, which enables the animals to exploit the shorter wavelengths characteristic of twilight, and a shift in the peak spectral reflectance of the tapetum lucidum (TL) from around 640 nm in summer to around 450 nm in winter, which increases retinal illumination at short wavelengths. Enhanced sensitivity to short wavelengths is likely to enhance the contrast of some objects and hence the ability of Rangifer to discriminate forage plants and to detect other animals (conspecifics or predators) against a snowy background under low illuminance. There is, nevertheless, currently no evidence of any specific boreal adaptation in their visual system: (i) The eyes of Rangifer, and by inference the area of the dilated pupil, are no larger than expected based on the allometry of eye size in ruminants. (ii) There is no evidence of a change in the spectral sensitivity of photoreceptors associated with detection of UVa. (iii) Transmission of UV through the anterior eye is not unique to Rangifer. (iv) The blue shift in the reflectance of the winter TL appears to be a passive response to prolonged dilation of the pupil and there is no a priori reason not to predict the same response in other large ungulates exposed to low light levels. (v) There is no conclusive evidence of a seasonal shift in absolute retinal sensitivity in Rangifer. (vi) Weak circadian organisation in Rangifer has tentatively been linked to mutations within the circadian molecular clockwork but it remains unclear to what extent this represents a specific adaptation to high latitude. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Although biologists have described biofluorescence in a diversity of taxa, there have been few systematic efforts to document the extent of biofluorescence within a taxonomic group or investigate its general significance. Through a field survey across South America, we discover and document patterns of biofluorescence in tropical amphibians. We more than triple the number of anuran species that have been tested for this trait. We find evidence for ecological tuning (i.e., the specific adaptation of a signal to the environment in which it is received) of the biofluorescent signals. For 56.58% of species tested, the fluorescence excitation peak matches the wavelengths most abundant at twilight, the light environment in which most frogs are active. Additionally, biofluorescence emission spans both wavelengths of low availability in twilight and the peak sensitivity of green-sensitive rods in the anuran eye, likely increasing contrast of this signal for a conspecific receiver. We propose an expanded key for testing the ecological significance of biofluorescence in future studies, providing potential explanations for the other half of fluorescent signals not originally meeting formerly proposed criteria. With evidence of tuning to the ecology and sensory systems of frogs, our results suggest frog biofluorescence is likely functioning in anuran communication. The significance of biofluorescence across taxonomic groups is understudied. Here the authors document biofluorescence in South American tropical amphibians, suggesting that biofluorescence corresponds with wavelengths of light at twilight and may be used in communication. [ABSTRACT FROM AUTHOR]

Photoreception is essential to coral growth, reproduction, and stress responses. Thus far, opsin-based photoreception and potential photoadaptation in Scleractinian corals remains unclear. This study used natural and light-emitting diode (LED) lighting to investigate how Acropora digitifera, which is adapted to shallow-water environments, responds to day–night conditions. We successfully cloned three opsin genes (Adopsin1, Adopsin2, and Adopsin3). Adopsin1 and Adopsin2 clustered with the Cnidopsins, whereas Adopsin3 clustered with the anthozoan-specific opsin I group. In situ hybridization showed positive signals of these genes in coral endodermal and ectodermal layers. When A. digitifera branches were reared under a day–night cycle with natural light, a day-high and night-low pattern was observed in the transcript levels of Adopsin1 and Adopsin3. Genes related to calcification [plasma membrane calcium transporting ATPase 2 (PMCA)] and oxygen homeostasis regulation [hypoxia-inducible factor 1 alpha (HIF1α)] showed similar patterns. Rearing of branches under a day–night cycle (photoperiod = 12:12, 26.5–29.3 μmol s−1 m−2) with red (λmax = 628 nm), but not blue (464 nm) or green (519 nm) LED lighting led to increases in transcript levels of Adopsin1 and Adopsin3 during photophase. The transcript levels of carbonic anhydrase, PMCA, HIFα, and sodium-glucose cotransporter were significantly higher during photophase than during scotophase. Furthermore, Adopsin3 upregulation occurred within 4 h of exposure to a red LED light at night. These results suggest that A. digitifera can responding to long wavelengths of light, which play a crucial role in the photophysiology of the coral host. The capacity to perceive red light provides advantages in physiological adaptation and ecological niche occupation by A. digitifera in shallow waters. [ABSTRACT FROM AUTHOR]

AbstractEven though accidents with pedestrians are more likely to have a severe or fatal outcome, most research concentrates on the vehicle part of the accidents. To make better policies and infrastructure decisions it is crucial to understand how and why such accidents happen. In this article, 2.588 pedestrian accidents from the year 2018 that resulted in injury or death in the city of Ankara, Türkiye are considered, and different attributes are analyzed co-location-wise. Three types of analysis will be undertaken for these accidents: temporal, natural environment, and pedestrian characteristics. The season of the year, weekend-weekday, and time of day will be explored for the temporal analysis. Visibility (daylight, twilight, and darkness) and rain are the natural surroundings of interest. The analyzed pedestrian characteristics are age group, gender, clothing colour, and nationality. Generally, the accident properties are evenly distributed and mostly the higher co-locations occur with themselves. Three important results stand out in this study. Firstly, the type of precaution appropriate to different time periods of the day should be applied, taking into account the locations that have the strongest co-location with themselves. Secondly, a seasonal approach should be adopted in determining places where pedestrian safety needs to be increased in the city. Lastly, pedestrian safety measures targeting especially both ‘0–14 and 65 + age groups’ and ‘foreign citizenship’ should be prioritized in the identified locations. The results show that the co-location methodology is a good fit for analyzing pedestrian accidents and a wider use of this methodology for other accident types and in general might be beneficial. [ABSTRACT FROM AUTHOR]

In recent years, breeding initiatives have been made to reduce the fecundity of invasive plants leading to sterile cultivars. The wildtype form of heavenly bamboo (Nandina domestica Thunb. (Berberidaceae) and seven cultivars were evaluated for landscape performance, fruit production and seed viability at three sites in Florida located in southwest, northcentral, and north Florida. For heavenly bamboo cultivars in north Florida, 'Emerald Sea', 'Greray' (Sunray®), 'Lemon-Lime', 'Murasaki' (Flirt™), 'SEIKA' (Obsession™), and 'Twilight' performed well throughout much of the study with average visual quality ratings between 3.54 and 4.60 (scale of 1 to 5). In northcentral Florida heavenly bamboo cultivars are 'Emerald Sea', 'Greray', 'Lemon-Lime', 'Murasaki', 'SEIKA', and 'Twilight' performed well throughout much of the study with average quality ratings between 4.49 and 4.94. In southwest Florida, 'Emerald Sea', 'Greray', 'Lemon-Lime', 'Murasaki', and 'SEIKA' performed well with average quality ratings between 3.40 and 4.83. At all three sites, 'Emerald Sea' and the wildtype were similar in size, having the greatest growth indices compared to medium-sized cultivars ('Greray', 'Lemon-Lime', 'Twilight' and 'SEIKA') and dwarf-sized cultivars ('Chime' and 'Murasaki'). For three consecutive fall-winter seasons of the study, 'Chime', 'Greray', and 'Lemon-Lime' heavenly bamboo did not fruit at any of the study sites. Among the three sites, 'Murasaki' had 97.7% to 99.9% fruit reduction, 'SEIKA' had 97.7% to 100% fruit reduction, and 'Twilight' had 95.9% to 100% fruit reduction compared to the wildtype at respective sites. Seeds collected from low fruiting cultivars ('Murasaki', 'SEIKA', and 'Twilight') had 33.3% to 66.7% viability, as determined by tetrazolium tests. In comparison, 'Emerald Sea' produced as much, if not more, fruit as the wildtype, especially in northern Florida, with seed viability ranging from 6.7% to 29.0% among sites. Nuclear DNA content of cultivars were comparable to the wildtype, suggesting they are diploids. These findings identified four low to no fruiting heavenly bamboo cultivars recommended for landscape use ('Lemon-Lime', 'SEIKA', 'Murasaki', and 'Greray'). [ABSTRACT FROM AUTHOR]

This is an essay about looking at the sun, which means that it is actually an essay about being unable to do so. The figure at its centre is the solar eclipse, which removes the sun from view but provides the occasion to gather and look for light in the first place. While exceptional, the solar eclipse nonetheless presents a middle or common ground of light – mere light whose limits are realised by a shared witness, akin to the everyday sunset. The sunset and the solar eclipse each chart the point at which light fails, when the sun drops below the horizon or is otherwise occluded. Moving through a series of photographs of the sun, this essay takes the sun's eclipse – that is, the sun's disappearance – as central to photography's own middle ground. [ABSTRACT FROM AUTHOR]

Retinal rods, the photoreceptors of twilight vision, are able to adapt to a wide range of illumination levels. The molecular mechanisms of light adaptation have received extensive study, though no less interesting is the question of what changes occur in the phototransduction cascade after the adaptive light stimuli terminate. Our previous studies demonstrated the phenomenon of adaptation memory in the rods of amphibians: after background illumination, photoreceptor light sensitivity was reduced for several minutes, while in the dark the current was restored in 20–30 sec. This indicates the existence of additional, as yet unknown, mechanisms regulating the phototransduction cascade and operating after the adaptive effect of light. In search of specific mechanisms capable of explaining the effect of adaptive memory, we conducted experiments recording currents from single rods in frogs to assess the basal activity of the effector enzyme of the phototransduction cascade, phosphodiesterase type 6, in the dark state and after saturating background illumination. This study showed that the post-adaptation state of rods is characterized by elevated basal phosphodiesterase activity, with gradual reduction to the dark value within tens of seconds after terminating the adapting background light. These results also suggest that the components of the phototransduction cascade in rods may undergo as yet unstudied post-adaptation changes. [ABSTRACT FROM AUTHOR]

With his doctrine of the "complete irresponsibility of man," Nietzsche in different ways complicates the opposition between responsibility and irresponsibility. This article traces the different and conflicting senses of irresponsibility throughout Nietzsche's development. First, the doctrine is shown to build on Nietzsche's early study of Heraclitus (section I), whom Nietzsche admired for expounding and embodying a radical "innocence" that was both responsible and irresponsible in different senses. When presented as "philosophical conviction" in Human, All too Human, Nietzsche paradoxically speculates about the doctrine's incorporation out of a sense of responsibility for the future of mankind (section II). Section III shows how Nietzsche's later writings evince an increasing awareness of this paradox by explicitly positing complete irresponsibility as his own redemptive doctrine in Twilight of the Idols. After 1881, he has come to affirm a new notion of responsibility and criticizes a weak sense of irresponsibility as the abdication of one's task. I end by discussing the relation of these different senses of irresponsibility, and argue that the fact that Nietzsche's texts often deliberately complicate rather than clarify such distinctions is an important reflection of how he textually takes responsibility for "complete irresponsibility" (section IV). [ABSTRACT FROM AUTHOR]

Abstract The phenomenon of twilight has been stipulated as naturally dependent on the variables of solar depression, aerosol concentration and ozone composition. The unique color spectrum of twilight is attributed by ozone layer and aerosol, whereas its brightness is heavily relying on the altitude of sun below horizon. While all the natural dependence is being researched extensively, the impact of light pollution on the brightness of the twilight is not being explored thoroughly. The objective of this study is to find out the alteration of light pollution towards the natural behavior of twilight sky brightness. Total of 84 data of twilight brightness was collected from 2014 until 2022 using Sky Quality Meter, and the specific location with profile classified as urban, suburban and pristine is investigated to study the impact of light pollution on twilight brightness. The result demonstrates that the stability of twilight brightness, which naturally factored by solar depression within the range of 18°, discovered to be heavy influenced by the zenith light pollution of the location sky, as evidenced by location that has zenith pollution of 17.11, 19.77, and 21.39, has horizontal twilight brightness of 14.84, 19.55 and 21.2 and solar depression during brightness stability at 11.5°, 15.67° and 17.49°.

Riverine caves are special habitats that are home to many aquatic and terrestrial species. Some Odonata species and their emerging are recorded at the entrance and in the twilight zones of subterranean habitats around the world. However, the emergence of any Odonata species has not been recorded in the dark zones of caves or other subterranean habitats. We report the first evidence of the emerging of the Hyrcanian Goldenring, Cordulegaster vanbrinkae Lohmann, 1993, as an endemic species of the Hyrcanian biogeographical region, in the dark zone of Danial Cave, in the World Heritage‐listed Hyrcanian Forests, northern Iran. During 2020–2023, three newly emerged and three exuviae of the species were recorded in the entrance zone (25 m) and the dark zone of the cave (200–280 m). The main hypothesis of the study is the entry and exit of adults from the cave entrance. However, we still do not know if the newly emerged will leave the cave or not. We still need more study on the biology and ecology of the species inside and around the cave. Danial Cave, with its high biodiversity, is one of the most important caves in the Middle East, and is urgently in need of conservation as a national natural monument. [ABSTRACT FROM AUTHOR]

Investigating the risk of road crashes associated with ambient light is often challenged by bias resulting from confounding effects of other risk factors. The study used the odds ratio and the risk ratio methods to isolate the effect of ambient light from other risk factors. This was possible in this research using the 'whole-year' approach adopted in previous research and utilising seasonal variations in ambient light in Cape Town. The analysis was based on crash and ambient light data collected between 2014 and 2018 in Cape Town. A total of 361 452 crashes were reported during this period. With only minor exceptions, the results confirm a higher crash risk in both twilight and dark conditions. The increase in the risk was different depending on the ambient light level, the crash type (total and pedestrian crashes) and the time of the day (morning and evening times). The results suggest that more efforts need to be made to assist road users to travel safely under twilight and dark conditions. [ABSTRACT FROM AUTHOR]

The theory of habitat heterogeneity, which treats one of the global drivers of biodiversity, is valid for several taxonomic groups and distinct ecosystems, including subterranean environments. However, knowledge about the factors that influence the structure of subterranean communities remains limited, especially in Neotropical regions. We sought to understand the main drivers of invertebrate species richness and composition. For that, we compared the substrate elements of twilight and deep-cave zones and their associated invertebrate communities. Variations in habitat heterogeneity were significantly related to richness in the deep cave zone, but had no effect on the fauna associated with the twilight zone. The local heterogeneity enhanced the richness in the deep cave zone due to the increase in the number of available habitats and the effect on decreasing niche overlap. For communities' composition, the geographic distribution of caves explained the similarity between the twilight zone of different caves. Therefore, nearby caves have a more similar fauna in the entrance regions but conversely, exhibit a higher dissimilarity between communities associated with the deep-cave zone. This study highlights the influence of local habitat heterogeneity on the invertebrate communities associated with different zones of the cave. [ABSTRACT FROM AUTHOR]

For biographer John Baxter, J. G. Ballard's The Drowned World (1962) echoes the work of neurophysiologist John C. Lilly, who, from 1954 onwards, conducted a series of sensory deprivation experiments with floatation tanks. Lilly's work paralleled that of psychologist Donald O. Hebb. Hebb used soundproof isolation chambers to simulate the withdrawal of sensory stimuli from test subjects. James Kennaway's novel The Mind Benders (1963) drew on these experiments whilst Paddy Chayefsky's Altered States (1978) took the visionary aspects of Lilly's work as its basis. In the case of Ballard, language redolent of this field of post-war experimentation appears across his career, in The Drowned World and short stories such as 'Manhole 69' (1957), 'The Gioconda of the Twilight Noon' (1964), and 'The Enormous Space' (1989). In each case the lack of sensory stimuli results in experiences of spatial, psychological, and temporal expansion. After unpacking the link between Ballard's texts and the surrounding context of sensory deprivation, this article marks out his thematic difference from the likes of Lilly, Kennaway, and Chayefsky et al. In examining this representation of men in the process of disappearing, this article uses the literature of sensory deprivation to re-focus Ballard's post-literary status back to the functionality of his writing. Further, it argues for a posthuman understanding of Ballard's predilection for terminal identities framed as transformative states. [ABSTRACT FROM AUTHOR]

Observations using Arecibo Observatory's highly sensitive Incoherent Scattering Radar (AO‐ISR) show ionospheric descending layers from as high as ∼400 km, much higher than earlier studies, with continuity down to 90 km. The AO‐ISR was operated to observe the ion‐line and plasma‐line with coded‐long‐pulse for high temporal and spatial resolution of 35/10 s and 300 m, respectively, during 01–06 February 2019. We found multiple layering structures descending from 400 to 90 km in all these six days. These layers are traditionally called intermediate descending layers (IDLs) (>130 km and below F‐peak), upper semi‐diurnal daytime and nighttime layers (110–130 km), and lower diurnal layers (<110 km). We have denoted the new daytime descending layers above the hmF2 as top‐side descending layers (TDLs). All these layers are collectively named ionospheric descending layers (IonDLs) since all of them are connected with some discontinuity at the F1‐peak (i.e., 170 km), except for the daytime lower‐diurnal layer. The most pronounced IonDLs occur in the twilight times. IonDLs mainly occur in shear zones of the vertical ion drifts and are favored by downward ion drifts, and their descent speeds increase with increasing altitude. The estimated phase velocities of the waves in the F‐region are comparable with the descending speed of the IonDLs. Furthermore, IonDLs/IDLs occur with and without spread‐F events but intensified spread‐F events raise their beginning altitude. The TDLs and IDLs are driven by gravity waves with periods of 1.5–4 hr. Key Points: We found ionospheric descending layers (IonDLs) that start near ∼400 km and descend down to ∼90 kmWe observe traditional intermediate descending layers (IDLs) starting from ∼300–350 km (below ∼170 km) during the nighttime (daytime)The daytime top‐side descending layers (from 400 km) and IDLs are governed by the waves with periods of ∼1.5–4 hr [ABSTRACT FROM AUTHOR]

The given text is a poem titled "The Arms of Shadow" by Sher Chandley. The poem explores themes of freedom, lightness, and the contrast between comfort and poverty. The author's words evoke a sense of restlessness and empathy towards the poor and sickly. The poem is part of a larger poetry book called "Soul of Humanity," which is dedicated to Palestine and its martyrs. [Extracted from the article]

A select few of "beginnings" among the Greeks are Homer's "Oceanus", Hesiod's "Chaos", Anaximander's "Boundless", Parmenides' "Being", Plato's "Form of the Good" and Aristotle's "Contemplation". Sequentially capturing an account of various beginnings in Greek mythology and philosophy, this article opens with Homer's "Oceanus", an elemental water-based beginning, and reaches its closing stage in Aristotle's "Contemplation", a conceptual beginning. Mythological beginnings of Homer and Hesiod have the characteristic of birth, philosophical beginnings of Plato and Aristotle, have the characteristic of causality, while the pre-Socratic beginnings of Anaximander and Parmenides hold a unique place of their own - they seem to be a likeness of both yet at the same time are discernable from them. This article is structured in three sections: after a brief introduction distinguishing mythology from philosophy, a description of Greek beginnings in mythology and philosophy is given in sequential pairs i.e. Homer/Hesiod, Anaximander/Parmenides and Plato/Aristotle. Finally, the conclusion presents the significance of sequentially capturing Greek beginnings in the metaphor of "dawn, twilight and dusk" which exhausts what they considered as visible and expressible. [ABSTRACT FROM AUTHOR]

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Copyright of Ethos (0860-8024) is the property of John Paul II Institute, Faculty of Philosophy, John Paul II Catholic University of Lublin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Decades of research have uncovered how plants respond to two environmental variables that change across latitudes and over seasons: photoperiod and temperature. However, a third such variable, twilight length, has so far gone unstudied. Here, using controlled growth setups, we show that the duration of twilight affects growth and flowering time via the LHY/CCA1 clock genes in the model plant Arabidopsis. Using a series of progressively truncated no-twilight photoperiods, we also found that plants are more sensitive to twilight length compared to equivalent changes in solely photoperiods. Transcriptome and proteome analyses showed that twilight length affects reactive oxygen species metabolism, photosynthesis, and carbon metabolism. Genetic analyses suggested a twilight sensing pathway from the photoreceptors PHY E, PHY B, PHY D, and CRY2 through LHY/CCA1 to flowering modulation through the GI-FT pathway. Overall, our findings call for more nuanced models of day-length perception in plants and posit that twilight is an important determinant of plant growth and development. [ABSTRACT FROM AUTHOR]

Seamounts are ecological oases nurturing abundant fisheries resources and epibenthic megafauna in the vast oligotrophic ocean. Despite their significance, the formation mechanisms underlying these seamount ecological oases remain uncertain. To shed light on this phenomenon, this study conducted interdisciplinary in situ observations focusing on a shallow seamount in the oligotrophic ocean. The findings show that the seamount's topography interferes with the oceanic current to generate lee waves, effectively enhancing the nutrient supply to the euphotic layer downstream of the seamount. This continuous supply enhances phytoplankton biomass and subsequently the grazing and diurnal vertical migration of zooplankton, rapidly transporting the augmented phytoplankton biomass to the aphotic layer. Unlike the cyclonic eddies that move in the upper ocean, seamounts stand at fixed locations creating a more efficient and steady active transport loop. This active transport loop connects the euphotic and twilight zones, potentially conveying nourishment to benthic ecosystems to create stereoscopic oases in the oligotrophic ocean. [ABSTRACT FROM AUTHOR]

The classification of vehicles presents notable challenges within the domain of image processing. Traditional models suffer from inefficiency, prolonged training times for datasets, intricate feature extraction, and variable assignment complexities for classification. Conventional methods applied to categorize vehicles from extensive datasets often lead to errors, misclassifications, and unproductive outcomes. Consequently, leveraging machine learning techniques emerges as a promising solution to tackle these challenges. This study adopts a machine learning approach to alleviate image misclassifications and manage large quantities of vehicle images effectively. Specifically, a contrast enhancement technique is employed in the pre-processing stage to highlight pixel values in vehicle images. In the feature segmentation stage, Mask-R-CNN is utilized to categorize pixels into predefined classes. VGG16 is then employed to extract features from vehicle images, while an autoencoder aids in selecting features by learning non-linear input features and compressing representation features. Finally, the CatBoost (CB) algorithm is implemented for vehicle classification (VC) in diverse critical environments, such as inclement weather, twilight, and instances of vehicle blockage. Extensive experiments are conducted using different large-scale datasets with various machine learning platforms. The findings indicate that CB (presumably a specific method or algorithm) attains the highest level of performance on the large-scale dataset named UFPR-ALPR, with an accuracy rate of 98.89%. [ABSTRACT FROM AUTHOR]

A fundamental function of cortical circuits is the integration of information from different sources to form a reliable basis for behavior. While animals behave as if they optimally integrate information according to Bayesian probability theory, the implementation of the required computations in the biological substrate remains unclear. We propose a novel, Bayesian view on the dynamics of conductance-based neurons and synapses which suggests that they are naturally equipped to optimally perform information integration. In our approach apical dendrites represent prior expectations over somatic potentials, while basal dendrites represent likelihoods of somatic potentials. These are parametrized by local quantities, the effective reversal potentials and membrane conductances. We formally demonstrate that under these assumptions the somatic compartment naturally computes the corresponding posterior. We derive a gradient-based plasticity rule, allowing neurons to learn desired target distributions and weight synaptic inputs by their relative reliabilities. Our theory explains various experimental findings on the system and single-cell level related to multi-sensory integration, which we illustrate with simulations. Furthermore, we make experimentally testable predictions on Bayesian dendritic integration and synaptic plasticity. Author summary: The only certainty is uncertainty. Whether it is the reconstruction of a three-dimension scene from the two-dimensional images on our retina or locating your lock in twilight, we have to make decisions and perform actions without knowing the exact state of our environment. In the presence of uncertainty, Bayesian probability theory provides formal recipes of how different pieces of information should be combined to gain maximal information. Indeed, behavioral experiments show that humans and other animals behave as if they operate according to these principles. However, so far it is unclear how the necessary computations are implemented by our biological substrate. By suggesting a new view on the dynamics of a broad class of neuron models, we show how these computations may be implemented by individual cortical neurons. Furthermore, we derive a novel model of synaptic plasticity from first principles and illustrate how a neuron equipped with these synapse dynamics learns to approximate Bayes-optimal decision makers. Finally, we interpret various experimental results in light of our proposed theory and make experimentally testable predictions. [ABSTRACT FROM AUTHOR]

The text is a collection of poetic verses by Forrest Gander, titled "From Mojave Ghost." The verses explore themes of self-reflection, grief, language, and the power of art. Gander, a writer and translator, draws on his personal experiences and observations to create evocative and introspective poetry. The collection delves into the complexities of human emotions and the search for meaning in life. [Extracted from the article]

The article discusses two books on the topic of peacebuilding and examines the evolution and challenges of the concept. The first book, "Peacebuilding in the United Nations: Coming into Life" by Fernando Cavalcante, explores the rise of peacebuilding since the 1990s and its transformation from theory to practice. The second book, "A Requiem for Peacebuilding?" edited by Jorg Kustermans, Tom Sauer, and Barbara Segaert, delves into the predicaments and criticisms of peacebuilding as an international practice. The article highlights the nuanced arguments presented in both books and raises questions about the future of peacebuilding in a changing global landscape. [Extracted from the article]

Perceptually natural SDR images should retain enough information for the human observer to estimate the time at which the actual HDR scene was captured. Previous experiments revealed new phenomena related to the variation in personal circadian features in daylight. In this study, we try to extend our hypothesis to twilight (mesoscopic) vision. The key idea of the confirmation process was to focus on the visual perception of full moon texture. The main result suggests that (1) Normalized Visual Percept (NVP) of twilight vision exists and is similar to that used in daylight, and furthermore (2) the former dynamic range is significantly wider than the latter, i.e., CR (contrast ratio) was more than 106:1 vs. 104:1. [ABSTRACT FROM AUTHOR]

In this article, we examine the significance of establishing participatory and consentful recordkeeping practice in the face of ubiquitous use of records beyond their original intent. Among such secondary uses is the decontextualisation of data as part of the 'industrialisation' of access and use of 'historical' records within current transactional contexts, together with a wide range of data sharing practices arising from contemporary data science paradigms. To situate the call to action for consentful recordkeeping practice, we begin the article by exploring how human ability to navigate through the perpetual twilight of records becomes increasingly murky when a wholesale approach to data collection and governance is applied by machine learning practitioners. We then re-frame some classical archival principles to align them with participatory approaches; specifically, by expanding the scope of Jenkinsonian 'moral defence' as an imperative for proactive engagement with the Archival Multiverse. We then describe a case study of consentful recordkeeping in practice, using the example of the AiLECS Lab's newly developed collection acquisition and management system. This principles-based framework informs our practices for collecting and curating datasets for machine learning research and development and aims to privilege the ongoing consent of those represented in records to their use. In the context of this work, our core premise is that technologies designed to prevent exploitation of children should aim to avoid underlying data practices that are themselves exploitative (of children or adults). [ABSTRACT FROM AUTHOR]

Elasmobranchs are slow‐growing marine predators whose populations have declined due to their susceptibility to overfishing, especially affecting species of large size. Rostroraja alba is a large skate that is currently classified as critically endangered.To address the effects of overfishing and promote the recovery of marine species and habitats, marine protected areas (MPAs) are a commonly implemented management strategy. A critical aspect of their success is using information on species' movement patterns; however, this is frequently not assessed for elasmobranchs.In this study, acoustic telemetry was used to monitor 30 R. alba in the Professor Luís Saldanha Marine Park (Portugal) to assess their long‐term movements in the context of a coastal MPA and to evaluate the contribution of this kind of spatial management to the conservation of this species.Immature individuals were more frequently captured than adults, which postulates this area as a potential nursery. The average residency was moderate and relatively consistent throughout the year, as was area use. No marked size or sex‐based differences in movement were noted. Individuals were more active and occurred in shallower waters at night and twilight, and occasional quick vertical movements into the water column, isolated or in sequence, were also noted.In general, the LSMP seems to offer stable protection to immature R. alba, with no strong seasonal variation. These results provide relevant input for adaptive management measures of this and other similar MPAs and highlight the contribution of these efforts to the protection of nursery areas. [ABSTRACT FROM AUTHOR]

Medium‐scale traveling ionospheric disturbances (MSTIDs) can significantly alter a region's ionosphere features, severely impacting the performance and stability of services such as shortwave communication and navigation positioning. By utilizing the total electron content (TEC) data from BeiDou geostationary satellites for 2022–2023, this study investigated the characteristics of MSTIDs over Hong Kong concerning local time and seasons. A total of 622 MSTID events were observed, classified into three types: daytime (10:00–17:00 LT), twilight (17:00–22:00 LT), and nighttime (22:00–02:00 LT). The occurrence rates and excitation mechanisms of the three types of MSTIDs were analyzed. Daytime and twilight MSTIDs had higher occurrence rates during winter, while nighttime MSTIDs had higher occurrence rates in summer and were even absent during winter. Overall, daytime MSTIDs were the most common, followed by twilight MSTIDs, while nighttime MSTIDs were less frequent. The propagation directions of MSTIDs exhibited anisotropy but showed some clustering patterns. Daytime MSTIDs exhibited high directional diversity during summer, but more concentrated in winter. Nighttime MSTIDs, on the other hand, were more focused during summer. It is worth noting that twilight MSTIDs exhibit similar climatological characteristics to daytime MSTIDs, which have not been observed in previous studies. It is suggested that daytime MSTIDs in the Hong Kong region are likely primarily generated by atmospheric gravity waves (AGWs) from low‐latitude regions, while nighttime MSTIDs are likely caused by Perkins instability. Twilight MSTIDs may originate from AGWs at the solar terminator, as well as daytime MSTIDs propagated from mid‐latitude areas. Key Points: MSTIDs during daytime, twilight, and nighttime over Hong Kong are statistically analyzed for the first time using BeiDou GEO satellitesThe occurrence of MSTIDs shows significant seasonality and local time dependence, with propagation directions exhibiting anisotropyTwilight MSTIDs display propagation characteristics similar to daytime MSTIDs, possibly related to AWGs generated at the solar terminator [ABSTRACT FROM AUTHOR]

Simple Summary: The nutrient strategy is a significant part of Gephyrocapsa huxleyi's physiology. Unlike other studies mainly focusing on photosynthesis, we conducted a short-term incubation to test the difference in phagocytosis capacity between diploid calcified G. huxleyi RCC1266 and haploid non-calcified G. huxleyi PML B92/11 in different light regimes. The results suggested that a higher percentage has been found in the non-calcified strain as compared to the calcified strain, no matter whether it was under light or in the dark. Additionally, the non-calcified strain showed a greater percentage in the dark than under light. Coccolithophores play a significant role in marine calcium carbonate production and carbon cycles, attributing to their unique feature of producing calcareous plates, coccoliths. Coccolithophores also possess a haplo-diplontic life cycle, presenting distinct morphology types and calcification states. However, differences in nutrient acquisition strategies and mixotrophic behaviors of the two life phases remain unclear. In this study, we conducted a series of phagocytosis experiments of calcified diploid and non-calcified haploid strains of coccolithophore Gephyrocapsa huxleyi under light and dark conditions. The phagocytosis capability of each strain was examined based on characteristic fluorescent signals from ingested beads using flow cytometry and fluorescence microscopy. The results show a significantly higher phagocytosis percentage on fluorescent beads in the bacterial prey surrogates of the non-calcified haploid Gephyrocapsa huxleyi strain, than the calcified diploid strain with or without light. In addition, the non-calcified diploid cells seemingly to presented a much higher phagocytosis percentage in darkness than under light. The differential phagocytosis capacities between the calcified diploid and non-calcified haploid Gephyrocapsa huxleyi strains indicate potential distinct nutritional strategies at different coccolithophore life and calcifying stages, which may further shed light on the potential strategies that coccolithophore possesses in unfavorable environments such as twilight zones and the expanding coccolithophore niches in the natural marine environment under the climate change scenario. [ABSTRACT FROM AUTHOR]

This article provides an overview of the life and philosophical ideas of Jan Patočka, a Czech philosopher who was influenced by Edmund Husserl and Martin Heidegger. Patočka believed that Europe was in decline and sought to rediscover the potential of philosophy in the face of this decline. He explored themes such as alienation, subjectivity, and the crisis of Enlightenment reason, drawing from his experiences living through historical events such as World War II and the Stalinist era. Patočka's philosophy emphasized the importance of human situatedness and embodiedness, rejecting absolutist truth claims and embracing the tension between embracing problematicity and aspiring to overcome it. The article also discusses Patočka's involvement in the human rights initiative Charter 77 and his lasting legacy. [Extracted from the article]

Background: The state of twilight consciousness is marked by a focused narrowing of awareness, maintaining vigilance and attention while simultaneously experiencing perceptual shifts in the surrounding environment. It is crucial to recognize that this twilight state represents not just a contraction but also an expansion of conscious experience. Summary: Substances of abuse, particularly new psychoactive substances, play a significant role in inducing this twilight state. They achieve this by deconstructing essential components of consciousness, such as the perception of time and space. Key Message: This paper aimed to explore the phenomenon of the twilight state of consciousness and shed light on how new psychoactive substances can alter the perception of time and space during this twilight phase, potentially triggering exogenous psychosis. This comprehensive inquiry employs a phenomenological approach to the study of consciousness, recognizing it as the primary tool for ascribing significance to this intricate yet often overlooked aspect of psychopathology. [ABSTRACT FROM AUTHOR]

This article discusses a case report of a 67-year-old woman with Parkinson's disease who experienced episodes of reduced responsiveness. These spells occurred after taking her first dose of levodopa and could last up to one hour. The article explains that these episodes were attributed to orthostatic hypotension, a condition where blood pressure drops when standing up. The patient was advised to drink ample water after waking up and postpone taking levodopa until after breakfast, which successfully eliminated the episodes. The article also discusses the "hypotensive twilight zone," a state of impaired consciousness caused by cerebral hypoperfusion, which can occur in orthostatic hypotension. The authors emphasize the importance of recognizing and properly diagnosing these episodes to prevent unnecessary disability and avoid increasing medication doses. [Extracted from the article]

Carbon nanomaterials are expected to be bright and efficient emitters, but structural disorder, intermolecular interactions and the intrinsic presence of dark states suppress their photoluminescence. Here, we study synthetically-made graphene nanoribbons with atomically precise edges and which are designed to suppress intermolecular interactions to demonstrate strong photoluminescence in both solutions and thin films. The resulting high spectral resolution reveals strong vibron-electron coupling from the radial-breathing-like mode of the ribbons. In addition, their cove-edge structure produces inter-valley mixing, which brightens conventionally-dark states to generate hitherto-unrecognised twilight states as predicted by theory. The coupling of these states to the nanoribbon phonon modes affects absorption and emission differently, suggesting a complex interaction with both Herzberg–Teller and Franck– Condon coupling present. Detailed understanding of the fundamental electronic processes governing the optical response will help the tailored chemical design of nanocarbon optical devices, via gap tuning and side-chain functionalisation. The authors demonstrate that the band structure of graphene nanoribbons is modulated by cove edges, brightening the luminescence 4-fold via emission from otherwise dark twilight states. High spectral resolution of the optical response reveals strong vibron-electron coupling [ABSTRACT FROM AUTHOR]

This study intends to explore unique patterns of sociolinguistic codes from two famous postcolonial novels, i.e., Twilight in Dehli by Ahmed Ali and Ice Candy Man by Bapsi Sidhwa. This is a qualitative descriptive study that employs Paul Simpsons' Theory of Narrative Stylistics as a framework. For the purpose of data analysis, three categories of words are formed to illustrate the differences between the words that could be translated, the words which had the possibility of being translated, and the words which could not be translated at all. The results of the study show that both of these postcolonial novels are replete with the words that have possibility for using alternative expressions in English, but the novelists have deliberately used the local words as a tool to manifest their true culture and identity. This study recommends to extend such probe of sociolinguistic codes on other postcolonial literary works to fortify these findings. [ABSTRACT FROM AUTHOR]

According to the Sonotope Hypothesis, the heterogenous nature of the acoustically sensed, but not yet interpreted, environmental sounds (i.e., sonoscape) is created by the spatial and temporal conformation of sonic patches (sonotopes) as recently been described in a Mediterranean rural landscape. We investigated the Sonotope Hypothesis in a mountain beech forest of the Northern Apennines, Italy that is notoriously poor in soniferous species. Our aim was to test whether sonotopes were temporally distinct over seasonal and astronomical timeframes and spatially configured in relation to vegetation variables. We used the Acoustic Complexity Index (ACItf) to analyze the heterogeneity of sonic information gathered from an array of 11 sound recorders deployed within a lattice of eleven 4-ha hexagonal sample sites distributed throughout a 48-ha managed beech forest. We visualized and described the temporal patterns of ACItf between seasons (May-June and July-August 2021), across six astronomical periods (Night I, Morning Twilight, Morning, Afternoon, Evening Twilight, and Night II), and according to two aggregated frequency classes (<2000 and >2000 Hz). We introduced Spectral Sonic Signature (SSS) calculated from the sequence of ACItf values along frequency bins as a descriptor of the dynamic production of sounds across spatial and temporal scales. We calculated Mean Spectral Dissimilarity to compare SSS values across temporal periods and between sample sites. We identified sonotopes by grouping similar SSS for each sample site generated from cluster analyses and visualized their spatial arrangements. Frequencies <2000 Hz (mainly geophonies from wind and rain) were more prevalent than frequencies >2000 Hz (mainly biophonies from songbirds). Despite there being no strong relationship to vegetation variables and minimal biophony and anthropophony, distinct sonotopes still emerged for every astronomical and seasonal period. This suggests that the sonoscape expresses distinct spatial and temporal sonotope configurations associated with the temporal and spatial patterns of geophysical events that generate geophonies with minimal animal or anthropogenic occurrences. A new strategy based on the reintroduction of indigenous trees and shrubs in managed clearings should be considered for enhancing local biodiversity conservation along with ecoacoustic monitoring based on the Sonotope Hypothesis. [ABSTRACT FROM AUTHOR]

This paper presents a rereading of David Little and Sumner Twiss's Comparative Religious Ethics in the context of its initial reception and legacy within the field of religious ethics and argues that we can read it more charitably as a piece of pragmatism rather than as a work of formalism or semi‐formalism. If one does not read Little and Twiss as committed positivists concerned with realizing a specific research program associated with the "twilight of logical empiricism," then their theoretical and methodological recommendations, illustrated in their case studies, appear more pragmatic in nature and less excessively rigid. By rereading Comparative Religious Ethics in this light, we can see more clearly its relevance for the field today, particularly regarding the fundamental importance of the discursive activity of practical reasoning, or the game of giving and asking for reasons, in the study of religious ethics. [ABSTRACT FROM AUTHOR]

Jockeying ahead of the 2024 national elections took center stage in Indonesia's political landscape in 2023. The selection of President Jokowi's son for a vice-presidential ticket signaled the continuation and intensification of dynastic politics. The economy faced headwinds, but Indonesia's trade balance remained in surplus and inflation was tamed. The government promoted its green transition agenda while facing pushback from local communities on environmental and labor issues. In foreign policy, the country hosted the ASEAN Summit, and Jokowi engaged in a flurry of diplomatic travels in the twilight of his presidency. [ABSTRACT FROM AUTHOR]