The Architectural Typology of Contemporary Façades for Public Buildings in the European Context

In contemporary architecture, a border between an exterior and an interior—a façade—is variously designed in terms of form, style, response to climate or culture, individual approach or tools used. Despite the diversity and multi-tread theoretical and practical discourse, the Authors propose the typology of contemporary façades for public buildings (open to society) in the context of European cities by extracting comprehensive architectural features. The term systematic reflects the complexness of the issue by the newly proposed element. Namely, it is a representation of a particular architectural feature with the use of scale. The elaboration consists of (1) an introduction with a literature review and thesis, (2) our aim and method, (3) a historical background; case studies, and systematics introduction (4) conclusions with typology proposal.

Rapid depletion of CTCF and cohesin proteins reveals dynamic features of chromosome architecture

SUMMARYThe interphase genome is mainly shaped by cohesin-mediated loop extrusion and cohesin-independent compartmentalization. Extrusion is a dynamic process of cohesin loading, loop extension and release. Cohesin release is mediated by WAPL. Loss of WAPL leads to the formation of longer loops and counters compartmentalization. The dynamics of these changes in chromosome organization have been unclear. We have used acute depletion of WAPL to show that within six hours cohesin accumulates at CTCF-bound loop anchors and extended loops are formed. When we deplete WAPL and CTCF simultaneously, new loops are formed between active genes. Surprisingly, active gene clustering is independent of cohesin. Stabilization of cohesin on chromatin leads to a decrease in compartmentalization, which is rapidly restored by depletion of cohesin. Our analyses show that loop extrusion counters compartmentalization and plays a central role in many aspects of chromosome organization.HIGHLIGHTSCohesin accumulates at CTCF-mediated chromatin loop anchors following WAPL depletion.Actively transcribed genes form long-range gene clusters independent of the cohesin complex.Plumes are a novel architectural feature of juxtaposed DNA formed by cohesin at open chromatin islands.Chromosome compartmentalization can be uncoupled from nuclear lamina interactions.

Plant Polymerase IV sensitizes chromatin through histone modifications to preclude spread of silencing into protein-coding domains

Heterochromatin is the predominant architectural feature of genomes that ensures genomic stability across eukaryotes. It mostly functions in restricting expression of repeats, mobile elements such as transposons and other regions. The establishment, maintenance and spreading of heterochromatin requires several factors including chromatin modifiers. However, how exactly heterochromatin formation is avoided in protein-coding domains is poorly understood. Here we show that a plant specific paralogue of RNA polymerase (pol) II, named pol IV, is involved in avoidance of facultative heterochromatic marks in protein coding genes, in addition to silencing the repeats and transposons forming constitutive heterochromatin. In its absence, H3K27 trimethylation mark intrudes the protein coding genes, more profoundly in genes embedded with repeats. In a subset of genes that lack the compensatory silencing, spurious transcriptional activity results in small(s)RNA production leading to post-transcriptional gene silencing. We show that such effects are significantly pronounced in rice, a plant with larger genome with distributed heterochromatin when compared to Arabidopsis. Our results indicate the surprising division of labour among plant-specific polymerases, not just in establishing effective silencing via small RNAs and epigenetics, but also in influencing chromatin boundaries.

MINARETS AS A VITAL ELEMENT OF INDO-ISLAMIC ARCHITECTURE: EVOLUTION AND MORPHOLOGY

The Minarets are a distinctive architectural feature of Islamic Mosques. The Minarets have become an essential and integral part of the mosque in the Indian sub-continent as like anywhere in the world. The Minarets evolved in Islamic Architecture at very early times. Although it was not an essential part of the mosque during the lifetime of the Prophet Muhammad (PBUH) and even for some time after the period after him, There are, however, many conflicting views as to exactly where, when and by whom were the first mina-rets built. The minarets were constructed for monumental purposes but became symbolic and became the permanent features of the mosque buildings. These minarets are being built in varied geographical and cultural environments. The Muslim architects used forms that have been acclimatized in their traditional cultures. The architects did not invent new forms but preferred to refine the existing ones with the highest proportion and integrity to the main building. Therefore, they had gone through a transition state in adapting the minarets form, keeping their cultural richness and transforming them into a religious identity most suited to the Islamic buildings. This paper reviews the mosque architecture in general, the various functional aspects of minarets, its evolution in history, and the forms that the architects in India had used to determine their roots and the process of transformation by which it had been recognized as a vital element in the Islamic buildings, especially the mosques.

Establishment of H3K9me3-dependent heterochromatin during embryogenesis in Drosophila miranda

Heterochromatin is a key architectural feature of eukaryotic genomes crucial for silencing of repetitive elements. During Drosophila embryonic cellularization, heterochromatin rapidly appears over repetitive sequences but the molecular details of how heterochromatin is established are poorly understood. Here, we map the genome-wide distribution of H3K9me3-dependent heterochromatin in individual embryos of Drosophila miranda at precisely-staged developmental time points. We find that canonical H3K9me3 enrichment is established prior to cellularization, and matures into stable and broad heterochromatin domains through development. Intriguingly, initial nucleation sites of H3K9me3 enrichment appear as early as embryonic stage3 over transposable elements (TE) and progressively broaden, consistent with spreading to neighboring nucleosomes. The earliest nucleation sites are limited to specific regions of a small number of recently active retrotransposon families and often appear over promoter and 5' regions of LTR retrotransposons, while late nucleation develops broadly across the entirety of most TEs. Interestingly, early nucleating TEs are strongly associated with abundant maternal piRNAs and show early zygotic transcription. These results support a model of piRNA-associated co-transcriptional silencing while also suggesting additional mechanisms for site-restricted H3K9me3 nucleation at TEs in pre-cellular Drosophila embryos.

Bow-tie architecture of gene regulatory networks in species of varying complexity

The gene regulatory network (GRN) architecture plays a key role in explaining the biological differences between species. We aim to understand species differences in terms of some universally present dynamical properties of their gene regulatory systems. A network architectural feature associated with controlling system-level dynamical properties is the bow-tie, identified by a strongly connected subnetwork, the core layer, between two sets of nodes, the in and the out layers. Though a bow-tie architecture has been observed in many networks, its existence has not been extensively investigated in GRNs of species of widely varying biological complexity. We analyse publicly available GRNs of several well-studied species from prokaryotes to unicellular eukaryotes to multicellular organisms. In their GRNs, we find the existence of a bow-tie architecture with a distinct largest strongly connected core layer. We show that the bow-tie architecture is a characteristic feature of GRNs. We observe an increasing trend in the relative core size with species complexity. Using studied relationships of the core size with dynamical properties like robustness and fragility, flexibility, criticality, controllability and evolvability, we hypothesize how these regulatory system properties have emerged differently with biological complexity, based on the observed differences of the GRN bow-tie architectures.

Restricted nucleation and piRNA-mediated establishment of heterochromatin during embryogenesis in Drosophila miranda

Heterochromatin is a key architectural feature of eukaryotic genomes, crucial for silencing of repetitive elements and maintaining genome stability. Heterochromatin shows stereotypical enrichment patterns around centromeres and repetitive sequences, but the molecular details of how heterochromatin is established during embryogenesis are poorly understood. Here, we map the genome-wide distribution of H3K9me3-dependent heterochromatin in individual embryos of D. miranda at precisely staged developmental time points. We find that canonical H3K9me3 enrichment patterns are established early on before cellularization, and mature into stable and broad heterochromatin domains through development. Intriguingly, initial nucleation sites of H3K9me3 enrichment appear as early as embryonic stage3 (nuclear cycle 9) over transposable elements (TE) and progressively broaden, consistent with spreading to neighboring nucleosomes. The earliest nucleation sites are limited to specific regions of a small number of TE families and often appear over promoter regions, while late nucleation develops broadly across most TEs. Early nucleating TEs are highly targeted by maternal piRNAs and show early zygotic transcription, consistent with a model of co-transcriptional silencing of TEs by small RNAs. Interestingly, truncated TE insertions lacking nucleation sites show significantly reduced enrichment across development, suggesting that the underlying sequences play an important role in recruiting histone methyltransferases for heterochromatin establishment.

Preventing the wind-induced vibration of arches during construction

<p>Arches are the most prominent architectural feature of tied-arch bridges and offer a dramatic visual impact. Arches rarely exhibit aerodynamic instabilities once tied to the bridge deck; however, during construction they typically have low fundamental frequencies, low inherent structural damping and low mass. This combination makes them especially vulnerable to wind-induced vibrations. The three-dimensionality of the arch shape is best examined through aeroelastic model wind tunnel testing as opposed to sectional model based approaches. In many cases vortex-induced oscillations have been observed for certain discrete stages of arch construction. In some cases, the loads induced by these vortex-induced oscillations can be tolerated by the structure; however, in other cases the responses can be sufficiently large that they must be prevented. Therefore, to prevent vortex-induced oscillations of the arches during construction, different damping strategies have been employed. Two practical methods that have been recently deployed include: (i) an in- line cable damper attached by a cable to the arch and anchored to a firm foundation, and (ii) tuned mass dampers (TMD). In this paper a background on the sources of wind-induced vibrations is presented along with methods to predict the response followed by several mitigation strategies.</p>

Unwrapping the micro-history of a house cistern from ancient Akrai/Acrae (southeastern Sicily)

The paper looks into the turbulent history of the ancient town of Akrai/Acrae in a mountainous part of southeastern Sicily, encapsulated in the assemblage of finds from a domestic cistern, which was remodeled and adapted in the course of its use. The cistern is considered as an architectural feature against the background of the ancient town, and the assemblage recovered from it is exmined thoroughly category by category, giving insight into the life of the ancient inhabitants of this island in the Mediterranean.