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This chapter will be divided into two parts. The first one will try to propose a more nuanced and complex approach, as paired with its archaeological penchant to the traditional historiographical juxtaposition continuity vs. discontinuity which has been the unavailable starting point in any discourse on the Byzantine city. It will propose a more Mediterranean-based approach to the trajectories of Byzantine urbanism encompassing the fragmentation of the Great Sea post-Late Antiquity and reaching out to the eleventh and twelfth-century when Byzantine cities were deeply embedded in a flourishing Mediterranean economy. The second part will move from another supposed juxtaposition (polis vs. kastron) to examine the historiographical debate concerning the fate of urbanism in the period spanning between the Late Antiquity and the Fourth Crusade. It will also present the reader with the main methodological issues concerning material and literary sources essential to analyze regional trajectories of urban city-life and cityscape.

This chapter presents the reader with three preliminary and different themes that will recur across the book as taking their cue from the changes of some exemplary Byzantine cities like Ephesos and Euchaita. The first has to do with the importance of tracking the transformation of the urban functions across space and time. The second concern the methodological approach adopted in the book. Indeed, the changes in urban functions, landscape, structure, and fabric will be explored by bringing together the most recent results stemming from urban archaeological excavations, the results of analyses of material culture (ceramic, coins, seals), and a reassessment of the documentary and hagiographical sources. The third aims to explain how Byzantine urban sites located in different parts of the empire (Byzantine heartland vis a vis the coastal-insula koine) reverberated the changes experienced by the political, social, and economic imperial super-structure a regional and sub-regional level.

Understanding star formation is key to understand galaxy evolution. Observations collected in the Herschel Infrared Galactic plane Survey (Hi-GAL) revealed the ubiquitous presence of filamentary structures in the Galactic Plane. Filaments host star formation. Therefore, it is very interesting to study them and analyze the environment effect on their life cycle. A first step in understanding filaments consists in detecting them in the Galactic Plane. Detection algorithms based on standard image processing techniques present several limitations. Taking into consideration the drastic progress in Artificial Intelligence (AI), along with the data abundance about filaments, we propose to explore filament segmentation using Deep Learning (DL) framework. In this paper, we use state-of-the-art image segmentation in DL, U-Net, to segment filaments in all the Galactic Plane, in H2 column density images of the Galactic Plane obtained with Herschel Hi-GAL data. The used ground truth consists in the Hi-GAL filament catalogue provided by Schisano et al. Obtained results reveal more structures than provided in the catalogue, which makes AI-based methods very promising for such application.

C. elegans is a well-characterized and relatively simple model organism, making it attractive for studying nuclear pore complex proteins in cell and developmental biology. C. elegans is transparent and highly amendable to genetic manipulation. Therefore, it is possible to generate fluorescently tagged proteins and combine this with various light microscopy techniques to study protein behavior in space and time. Here, we provide protocols to prepare both fixed and live C. elegans for confocal and light sheet microscopy. This enables the analysis of nuclear pore complex proteins from embryonic stages to the aging adult.

We present the properties of magnetic fields (B-fields) in two clumps (clump 1 and clump 2), located at the waist of the bipolar H II region Sh2-201, based on JCMT SCUBA-2/POL-2 observations of 850 $\mu$m polarized dust emission. We find that B-fields in the direction of the clumps are bent and compressed, showing bow-like morphologies, which we attribute to the feedback effect of the H II region on the surface of the clumps. Using the modified Davis-Chandrasekhar-Fermi method we estimate B-fields strengths of 266 $\mu$G and 65 $\mu$G for clump 1 and clump 2, respectively. From virial analyses and critical mass ratio estimates, we argue that clump 1 is gravitationally bound and could be undergoing collapse, whereas clump 2 is unbound and stable. We hypothesize that the interplay between thermal pressure imparted by the H II region, B-field morphologies, and the various internal pressures of the clumps (such as magnetic, turbulent, and gas thermal pressure), has the following consequences: (a) formation of clumps at the waist of the H II region; (b) progressive compression and enhancement of the B-fields in the clumps; (c) stronger B-fields will shield the clumps from erosion by the H II region and cause pressure equilibrium between the clumps and the H II region, thereby allowing expanding I-fronts to blow away from the filament ridge, forming bipolar H II regions; and (d) stronger B-fields and turbulence will be able to stabilize the clumps. A study of a larger sample of bipolar H II regions would help to determine whether our hypotheses are widely applicable., Comment: 25 pages, 10 figures, and 4 tables. Accepted for publication in ApJ

[Abridged] The interstellar medium is observed to be organised in filamentary structures, as well as neutral (HI) and ionized (HII) bubbles. The expanding nature of these bubbles makes them shape their surroundings and possibly play a role in the formation and evolution of interstellar filaments. We present APEX $^{13}$CO and C$^{18}$O(2-1) observations of the NGC 6334 molecular cloud. We investigate the gas velocity structure along and across the 50 pc-long cloud and towards 75 identified velocity-coherent-filaments (VCFs). We measure a wealth of velocity gradients along the VCFs. We derive the column density and velocity power spectra of the VCFs. These power spectra are well represented with power laws showing similar slopes for both quantities (with a mean of about -2), albeit some differ by up to a factor of two. The position velocity diagrams perpendicular to three VCFs show the V-shaped velocity pattern, corresponding to a bent structure in velocity space with the filament at the tip of the V surrounded by an extended structure connected to it with a velocity gradient. This velocity structure is qualitatively similar to that resulting from numerical simulations of filament formation from large-scale compression from propagating shock fronts. In addition, the radial profiles perpendicular to these VCFs hint to small-scale internal impacts from neighbouring HII bubbles. The observed opposite curvature in velocity space towards the VCFs points to various origins of large-scale external compressions from propagating HI bubbles. This suggests the plausible importance of multiple HI compressions, separated in space and time, in the formation and evolution of molecular clouds and their star formation history. These latter atomic compressions due to past and distant star formation events are complemented by the impact of HII bubbles from present time and local star formation activity., Accepted for publication in Astronomy & Astrophysics

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Ionized gas probes the influence of massive stars on their environment. The Cygnus X region (d~1.5 kpc) is one of the most massive star forming complexes in our Galaxy, in which the Cyg OB2 association (age of 3-5 Myr and stellar mass $2 \times 10^{4}$ M$_{\odot}$) has a dominant influence. We observe the Cygnus X region at 148 MHz using the Low Frequency Array (LOFAR) and take into account short-spacing information during image deconvolution. Together with data from the Canadian Galactic Plane Survey, we investigate the morphology, distribution, and physical conditions of low-density ionized gas in a $4^{\circ} \times 4^{\circ}$ (100 pc $\times$ 100 pc) region at a resolution of 2' (0.9 pc). The Galactic radio emission in the region analyzed is almost entirely thermal (free-free) at 148 MHz, with emission measures of $10^3 < EM~{\rm[pc~cm^{-6}]} < 10^6$. As filamentary structure is a prominent feature of the emission, we use DisPerSE and FilChap to identify filamentary ridges and characterize their radial ($EM$) profiles. The distribution of radial profiles has a characteristic width of 4.3 pc and a power-law distribution ($β= -1.8 \pm 0.1$) in peak $EM$ down to our completeness limit of 4200 pc cm$^{-6}$. The electron densities of the filamentary structure range from $10 < n_e~{\rm[cm^{-3}]} < 400$ with a median value of 35 cm$^{-3}$, remarkably similar to [N II] surveys of ionized gas. Cyg OB2 may ionize at most two-thirds of the total ionized gas and the ionized gas in filaments. More than half of the filamentary structures are likely photoevaporating surfaces flowing into a surrounding diffuse (~5 cm$^{-3}$) medium. However, this is likely not the case for all ionized gas ridges. A characteristic width in the distribution of ionized gas points to the stellar winds of Cyg OB2 creating a fraction of the ionized filaments through swept-up ionized gas or dissipated turbulence., 19 pages, 14 figures, 1 table; accepted for publication in A&A

The visual system often relies on prior assumptions when interpreting ambiguous visual inputs. A well-known example is the light-from-above prior, which aids the judgment of an object's three-dimensional (3-D) shape (i.e., convex or concave). Recent studies have revealed that the light-from-above prior also helps solve lightness ambiguity. This study aimed to examine whether 3-D shape perception and lightness perception share the same lighting prior. The study participants performed two tasks: one focusing on lightness perception and another focusing on 3-D shape perception. The dominant directions of the assumed lighting were calculated from participants’ performance in the two tasks. The results showed that the assumed lighting direction for 3-D shape perception were considerably biased toward the left, whereas the one for lightness perception was almost from directly above. The clear difference between these two directions supports the hypothesis that the visual system uses distinct lighting priors for 3-D shape perception and lightness perception. Experiments 1 and 2 involved Japanese speaking participants and European participants, respectively. The Japanese language can be read and written both horizontally (i.e., left to right) and vertically (i.e., up to down) with lines progressing from right to left. Nevertheless, the two experiments still produced the same result, which suggests that the present finding is universal regardless of reading/writing direction.

E-motions are defined as those affective states the expressions of which—conveyed either by static faces or body posture—embody a dynamic component and, consequently, convey a higher sense of dynamicity than other emotional expressions. An experiment is presented, aimed at testing whether e-motions are perceived as such also by individuals with autism spectrum disorders (ASDs), which have been associated with impairments in emotion recognition and in motion perception. To this aim we replicate with ASD individuals a study, originally conducted with typically developed individuals (TDs), in which we showed to both ASD and TD participants 14 bodiless heads and 14 headless bodies taken from eleven static artworks and four drawings. The Experiment was divided into two sessions. In Session 1 participants were asked to freely associate each stimulus to an emotion or an affective state (Task 1, option A), if they were unable to find a specific emotion, the experimenter showed them a list of eight possible emotions (words) and asked them to choose one from such list, that best described the affective state portrayed in the image (Task 1, option B). After their choice, they were asked to rate the intensity of the perceived emotion on a seven point Likert scale (Task 2). In Session 2 participants were requested to evaluate the degree of dynamicity conveyed by each stimulus on a 7 point Likert scale. Results showed that ASDs and TDs shared a similar range of verbal expressions defining emotions, however, ASDs (i) showed an impairment in the ability to spontaneously assign an emotion to a headless body, and (ii) they more frequently used terms denoting negative emotions (for both faces and bodies) as compared to neutral emotions, which in turn were more frequently used by TDs. No difference emerged between the two groups for positive emotions, with happiness being the emotion better recognized in both faces and in bodies. Although overall there are no significant differences between the two groups with respect to the emotions assigned to the images and the degree of perceived dynamicity, the interaction Artwork x Group showed that for some images ASDs assigned a different value than TDs to perceived dynamicity. Moreover, two images were interpreted by ASDs as conveying completely different emotions than those perceived by TDs. Results are discussed in light of the ability of ASDs to resolve ambiguity, and of possible different cognitive styles characterizing the aesthetical/emotional experience.

This work summarizes research conducted by the author over the years aimed at studying the perception of light in achromatic settings carried out by combining an experimental phenomenological approach with psychophysical methods. Concepts such as “reality” and “illusion” and basic lightness/brightness terminology are briefly analyzed. The perception of light is then treated in three paragraphs, each dedicated to a specific aspect: Luminosity, environmental illumination, and surface illumination (the last largely in relation to lightness perception). For each type of light perception, demos are presented along with a brief discussion of experimental studies conducted by the author and collaborators.

This chapter will navigate through the many incarnations of Byzantine urbanism in three different geographical areas of the empire: Anatolia and Aegean (the two constitutive pillars of the Byzantine heartland) and the so-called insular/coastal koine. Each of these played a changing and diverse role in the political, administrative, fiscal, and military strategies of the empire, as well as betraying peculiar economies of scale. It will examine by proposing a brief historical and archaeological overview of a selection of urban centers in different geographical contexts. This should help the reader see through the various functional trajectories of the Byzantine city (sometimes contemporary, sometimes diachronic) from a comparative perspective. It allows to extrapolate the reality of Byzantine urbanism from the historiographical and terminological debate as presented by the literary sources.