Versatile Domain Research Articles

Constructing superparaelectric polar structure for dielectric energy storage

To meet the miniaturization demands of next-generation electronics and electrical systems, energy storage capacitors with both high energy density and efficiency have become a research hotspot. Ferroelectric-based dielectrics are primary candidates due to the existence of spontaneous polarization and versatile domain structures. Since domains are fundamental structure units that respond to the external electric field, domain engineering is a general route to realizing high energy storage performance. In this perspective, we introduce a type of dielectrics, proposed recently and termed superparaelectrics, which has ultrasmall polar clusters (several unit cells) and exhibits nearly zero hysteresis and relatively high polarization due to the highly dynamical polar structure. Fundamental concepts of superparaelectricity are overviewed, and representative examples with state-of-the-art energy storage performance are reviewed to demonstrate the advantages of superparaelectrics. Finally, perspectives are provided about the future development of superparaelectric and electrostatic energy storage fields.

One Fits Many: Class Confusion Loss for Versatile Domain Adaptation.

In the open world, various label sets and domain configurations give rise to a variety of Domain Adaptation (DA) setups, including closed-set, partial-set, open-set, and universal DA, as well as multi-source and multi-target DA. It is notable that existing DA methods are generally designed only for a specific setup, and may under-perform in setups they are not tailored to. This paper shifts the common paradigm of DA to Versatile Domain Adaptation (VDA), where one method can handle several different DA setups without any modification. Towards this goal, we first delve into a general inductive bias: class confusion, and then uncover that reducing such pairwise class confusion leads to significant transfer gains. With this insight, we propose one general class confusion loss (CC-Loss) to learn many setups. We estimate class confusion based only on classifier predictions and minimize the class confusion to enable accurate target predictions. Further, we improve the loss by enforcing the consistency of confusion matrices under different data augmentations to encourage its invariance to distribution perturbations. Experiments on 2D vision and 3D vision benchmarks show that the CC-Loss performs competitively in different mainstream DA setups.

Biological Investigations of Three Marine Algae Enteromorpha intestinalis, Rhizoclonium riparium and Ceratophyllum demersum Collected from the Bay of Bengal

The ocean consists of versatile domain of lives which can be exploited for human health benefits because of diversified secondary metabolites. Seaweeds, generally called macroalgae, are commonly found in the coastal region of the Bay of Bengal. But none of them were investigated properly for their biological activities. Hence, this study was performed to investigate the antioxidant, antimicrobial, cytotoxic and membrane stabilizing activities along with total phenolic content of the crude methanolic extract of three seaweeds namely, Enteromorpha intestinalis, Rhizoclonium riparium and Ceratophyllum demersum using standard protocols. Among the methanolic extracts of three seaweeds, C. demersum (52.09 ± 1.30 mg of GAE) was found to have the highest phenolic content, followed by E. intestinalis (35.98 ± 1.27 mg of GAE) and then R. riparium (29.94 ± 0.54 mg of GAE). The extractives of these seaweeds also showed promising antioxidant and membrane stabilizing properties compared to the standard. E. intestinalis extract displayed greater reducing power with increasing concentration (EC50 value 7.70 ± 0.27 μg/ml). The same seaweed E. intestinalis was found to have significant free radical (DPPH) scavenging potential (IC50 value 23.46 ± 0.54 μg/ml) compared to the reference standard ascorbic acid (IC50 value 5.76 ±0.13 μg/ml). However, the findings of antimicrobial activity test demonstrated mild antibacterial effects of these seaweeds against Escherichia coli and Aspergillus niger and none of these seaweeds exhibited cytotoxicity when tested against HeLa cell line. These findings will aid in future studies attempting to explore medicinal and therapeutic agents from these readily available seaweeds of Bangladesh. Dhaka Univ. J. Pharm. Sci. 22(1): 81-87, 2023 (June)

An Approach to Solve Some Unsolved Limitations: Rough Set Theory

Rough set theory is a mathematical approach to dealing with uncertainty and vagueness in data. It was introduced as a way to approximate classical sets using lower and upper bounds. Rough set theory has been applied to various domains such as data mining, knowledge discovery, machine learning, soft computing, medical analysis, synthesis of switching circuits, and civil engineering. Rough set theory can handle imprecise and noisy data by finding structural relationships and dependencies among attributes. It can also reduce redundant and irrelevant attributes and generate decision rules from data. Rough set theory is closely related to fuzzy set theory, but differs in that it uses multiple memberships instead of partial memberships to model uncertainty. Lot of research works have taken place in this domain with many fruitful outcomes that helped lot in expanding this field to much wider reach of knowledge irrespective of the domain concerned to mathematical and technological application development. In lieu of such research-oriented progress in different versatile domain, many areas of research has remained untouched as many a problem remained unsolved being shrouded under the mystery. This paper deals mainly with some of the still unsolved questions on Rough Set that are under study for new discovery and a way to overcome such limitations citing proper techniques, examples, working models, and graphs.

Exploring an aromatic dicarboxylic acid-grafted supramolecular Cd(II)-metallogel: The mechanically flexible stuff for achieving MoS2, MoSe2, WS2, GO, and h(BN) 2D nanosheets-dispersed versatile supramolecular gel-nano composites

We have presented terephthalic acid, acting as a low molecular weight organic gelator, based Cd(II) metallogel system (Cd-TA) with DMF solvent formed through the interplaying supramolecular connectivity. The mechanical flexibility of the Cd-TA has been studied with the support of rheological tests confirming the gel-like feature of Cd-TA. The microstructural pattern of Cd-TA has been imaged through field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The structural flexibility of the Cd-TA has been executed to achieve diverse nanosheets dispersed supramolecular type gel-nano composites. Diverse 2-D nanostructures including graphene oxide (GO), diverse transition metal dichalcogenides like MoS2, MoSe2, WS2, and hexagonal boron nitride have been used to become 2-D nanosheet-dispersed supramolecular gel-nano composites of Cd-TA. The microstructural difference of the Cd(II)-metallogel with respect to versatile 2-D nanostructures mediated gel-nano composites of graphene oxide (GO), diverse transition metal dichalcogenides like MoS2, MoSe2, WS2, and hexagonal boron nitride have been thoroughly investigated through FESEM studies. The profound FESEM microstructural variations of different nanostructure based gel-nano composites of Cd-TA unequivocally establish that predominant contribution of supramolecular facets among the gel-nano composites forming chemical ingredients including 2D nanostructures of MoS2, MoSe2, WS2, and hexagonal boron nitride. These supramolecular gel-nano composites might be prospective for exploring mechanically flexible soft functional scaffold-based devices applicable for the technological uses in versatile domain.

Energy-efficient sensory data gathering in IoT networks with mobile edge computing

The Internet of Things (IoT) networks have been adopted ubiquitously to support domain applications. Specially, social robots have become an important part of IoT networks as smart devices and are widely used to support versatile domain applications. In this setting, gathering sensory data from social-aware mobile robots in an energy-efficient manner is of importance for prolonging the network lifetime and promoting proper decision-making. Considering the large-scale and spatial-temporal evolutional characteristic of IoT networks, social robots roam over time to deal with tasks, especially when considering fact that it may hardly be predicted for the regions and time durations that certain anomalies may occur. Therefore, this paper proposes to adopt mobile edge computing to support sensory data gathering. Edge nodes in edge networks gather sensory data from their subordinating social robots in a periodic manner. We design an edge network division method by constructing an improved Sort-Tile-Recursive (STR) tree, which can cluster the edge nodes and decrease unnecessary energy consumption. Experimental results show that our technique is more efficient than traditional ones in decreasing energy consumption.

Scanning stereo-PLIF method for free surface measurements in large 3D domains

In this work, we extend a planar laser-induced fluorescence method for free surface measurements to a three-dimensional domain using a stereo-camera system, a scanning light sheet, and a modified self-calibration procedure. The stereo-camera set-up enables a versatile measurement domain with self-calibration, improved accuracy, and redundancy (e.g., possibility to overcome occlusions). Fluid properties are not significantly altered by the fluorescent dye, which results in a non-intrusive measurement technique. The technique is validated by determining the free surface of a hydraulic flow over an obstacle and circular waves generated after droplet impact. Free surface waves can be accurately determined over a height of L=100 mm in a large two-dimensional domain (y(x,z) = 120times 62 mm^2), with sufficient accuracy to determine small amplitude variations (eta approx 0.2 mm). The temporal resolution ({varDelta }t = 19 ms) is only limited by the available scanning equipment (f = 1 kHz rate). For other applications, this domain can be scaled as needed.Graphic abstract

ThiN as a Versatile Domain of Transcriptional Repressors and Catalytic Enzymes of Thiamine Biosynthesis.

Thiamine biosynthesis is commonly regulated by a riboswitch mechanism; however, the enzymatic steps and regulation of this pathway in archaea are poorly understood. Haloferax volcanii, one of the representative archaea, uses a eukaryote-like Thi4 (thiamine thiazole synthase) for the production of the thiazole ring and condenses this ring with a pyrimidine moiety synthesized by an apparent bacterium-like ThiC (2-methyl-4-amino-5-hydroxymethylpyrimidine [HMP] phosphate synthase) branch. Here we found that archaeal Thi4 and ThiC were encoded by leaderless transcripts, ruling out a riboswitch mechanism. Instead, a novel ThiR transcription factor that harbored an N-terminal helix-turn-helix (HTH) DNA binding domain and C-terminal ThiN (TMP synthase) domain was identified. In the presence of thiamine, ThiR was found to repress the expression of thi4 and thiC by a DNA operator sequence that was conserved across archaeal phyla. Despite having a ThiN domain, ThiR was found to be catalytically inactive in compensating for the loss of ThiE (TMP synthase) function. In contrast, bifunctional ThiDN, in which the ThiN domain is fused to an N-terminal ThiD (HMP/HMP phosphate [HMP-P] kinase) domain, was found to be interchangeable for ThiE function and, thus, active in thiamine biosynthesis. A conserved Met residue of an extended α-helix near the active-site His of the ThiN domain was found to be important for ThiDN catalytic activity, whereas the corresponding Met residue was absent and the α-helix was shorter in ThiR homologs. Thus, we provide new insight into residues that distinguish catalytic from noncatalytic ThiN domains and reveal that thiamine biosynthesis in archaea is regulated by a transcriptional repressor, ThiR, and not by a riboswitch.IMPORTANCE Thiamine pyrophosphate (TPP) is a cofactor needed for the enzymatic activity of many cellular processes, including central metabolism. In archaea, thiamine biosynthesis is an apparent chimera of eukaryote- and bacterium-type pathways that is not well defined at the level of enzymatic steps or regulatory mechanisms. Here we find that ThiN is a versatile domain of transcriptional repressors and catalytic enzymes of thiamine biosynthesis in archaea. Our study provides new insight into residues that distinguish catalytic from noncatalytic ThiN domains and reveals that archaeal thiamine biosynthesis is regulated by a ThiN domain transcriptional repressor, ThiR, and not by a riboswitch.

Power Dynamics of India’s Space Program

ABSTRACTSpace power is a relatively nascent discourse that is gaining importance globally. This article examines India’s space program within the global context in order to understand the shifting power balance in the space arena. The article first clarifies contextual variants of the definition of power, recalibrating those formulations to the space context. This is followed by an examination of the Indian space program—its evolution historically, current limitations, and increasing relevance today. Space is a versatile domain and, due to its interconnected nature, it impacts the world. Hence, this article also examines global engagements and collaborative efforts being made across borders, and the strategic modalities involved in traversing such sensitive diplomatic terrain. Finally, the article concludes by reiterating the soft power and hard power potentials of the space arena, whose versatility contributes towards intrinsic national growth and extrinsic power projections.

The RpfC (Rv1884) atomic structure shows high structural conservation within the resuscitation-promoting factor catalytic domain.

The first structure of the catalytic domain of RpfC (Rv1884), one of the resuscitation-promoting factors (RPFs) from Mycobacterium tuberculosis, is reported. The structure was solved using molecular replacement once the space group had been correctly identified as twinned P21 rather than the apparent C2221 by searching for anomalous scattering sites in P1. The structure displays a very high degree of structural conservation with the previously published structures of the catalytic domains of RpfB (Rv1009) and RpfE (Rv2450). This structural conservation highlights the importance of the versatile domain composition of the RPF family.

UV Direct Write Metal Enhanced Redox (MER) Domain Engineering for Realization of Surface Acoustic Devices on Lithium Niobate

A new and highly versatile domain patterning method—ultraviolet direct write metal enhanced redox (UV direct write MER)—achieves deep domains with practically no thermally‐induced damage on the surface of lithium niobate crystals. In UV direct write MER, after coating with a thin layer of chromium, the domain inversion is generated by a redox process induced in the crystal by illumination with high intensity UV in an ambient dry nitrogen atmosphere. This new technique enables the fabrication of practical piezoelectric acoustic superlattice structures on 128° YX‐cut LiNbO3, the most widely used crystal cut for surface acoustic wave applications. For example, UV direct write MER was used to form an acoustic superlattice 128° YX structure that in turn enabled the generation of surface acoustic waves of sufficient strength to develop fluid flow within a droplet of water, demonstrating its potential in practical microfluidic manipulation. This is the first demonstration of a UV direct write surface acoustic wave transducer reported to date, made possible only due to the unique qualities of the MER domain engineering process.

Postural assessment of arbitrarily taken portrait and profile photographs using ImageJ

Summary A generic methodology to compare and quantify two photographs of body posture, taken under non-standard conditions is proposed in the current work. Suitable digital image processing tools are employed to accentuate the use of imaging technology to assess the posture. ImageJ , a versatile public domain image-processing tool has been employed to carry out the postural analysis. In this paper, we have described two case studies. Postural analysis is carried out on the portrait and profile photographs of the subjects taken arbitrarily, before and after one yoga session to demonstrate the method. Since this study deals with the photographs of the subject, which are arbitrarily taken, emphasis is laid on the normalization aspect of the photographs, after which the postural assessment aspect is discussed.

Nature's Design for a Versatile Interaction Domain

The gp130 protein is a shared receptor subunit that binds to at least 10 different cytokines. Boulanger et al. were therefore curious what features of gp130 would allow interaction with such a range of structurally dissimilar cytokines. Comparison of various cytokine-gp130 crystal structures showed that in fact the interactions predominantly occur through a single region of gp130. Furthermore, a crystal structure of the cytokine leukemia inhibitory factor (LIF) with the cytokine binding region of gp130 showed this region of the gp130 protein to be unusually rigid. Thus, the authors argue that gp130 is unlikely to accommodate its multiple ligands through conformational changes. Further analysis of the interaction by computational alanine scanning mutagenesis and thermodynamic measurements made by isothermal titration calorimetry support what the authors call a "thermodynamic plasticity" of the interaction site. Depending on the nature of the ligand, the interaction site of gp130 offers either polar interactions or hydrophobic interactions that favor binding in a manner that is relatively insensitive to ligand structure. Release of bound water molecules appears to contribute favorable gain in entropy to the binding reactions. Some gp130-interacting cytokines interact through another domain with a separate α-receptor subunit. In this case, the interaction mechanism is very different: It is sensitive to ligand structure and entropically unfavorable, relying primarily on hydrogen bonds and salt bridges. The authors note that the gp130 system offers a potential therapeutic target for a large range of physiological processes, and better understanding of its multiple interactions may allow strategies that specifically alter a particular action of this multifaceted signaling molecule. M. J. Boulanger, A. J. Bankovich, T. Kortemme, D. Baker, K. C. Garcia, Convergent mechanisms for recognition of divergent cytokines by the shared signaling receptor gp130. Mol. Cell 12 , 577-589 (2003). [Online Journal]

Nature's Design for a Versatile Interaction Domain

Nature's Design for a Versatile Interaction Domain

Coiled-coil proteins associated with type III secretion systems: a versatile domain revisited.

The pathogenic potential of many Gram-negative bacteria is indicated by the possession of a specialized type III secretion system that is used to deliver virulence effector proteins directly into the cellular environment of the eukaryotic host. Extracellular assemblies of secreted proteins contrive a physical link between the pathogen and host cytosol and enable the translocated effectors to bypass the bacterial and host membranes in a single step. Subsequent interactions of some effector proteins with host cytoskeletal and signalling proteins result in modulation of the cytoskeletal architecture of the aggressed cell and facilitate entry, survival and dissemination of the pathogen. Although the secreted components of type III secretion systems are diverse, many are predicted to share a common coiled-coil structural feature. Coiled-coils are ubiquitous and highly versatile assembly motifs found in a wide range of structural and regulatory proteins. The prevalence of these domains in secreted virulence effector proteins suggests a fundamental contribution to multiple aspects of their function, and evidence accumulating from functional studies suggests an intrinsic involvement of coiled-coils in subunit assembly, translocation and flexible interactions with multiple bacterial and host proteins. The known functional flexibility that coiled-coil domains confer upon proteins provides insights into some of the pathogenic mechanisms used during interaction with the host.

Resource traces: a domain for processes sharing exclusive resources

The domain of partially terminated finite and infinite words is commonly used to give denotational semantics for process algebras such as CSP. In this well-known framework the denotational semantics of concurrency is derived via power-domains from that of non-deterministic choice and interleaving to the effect that the denotational semantics of a concurrent process is equal to the set of all its possible finite and infinite sequential behaviours. In this paper, we define a more versatile domain of the so-called finite and infinite resource traces which allows to capture the concurrent behaviour of a process and encode the static concurrency of a system directly into the domains definition. The approach we present refines the previous work of Diekert and Gastin (Lecture Notes in Computer Science, vol. 944, Springer, Berlin, pp. 15–26) on α- and δ-traces. We start with an alphabet of atomic actions, a set of resources, and a resource map assigning to each action the non-empty subset of resources it uses. Actions that do not share common resources are called independent and considered to be able to execute concurrently. A partially terminated concurrent process is specified by a resource trace which consists of two components: an already observed part represented as an action-labeled partial order (Mazurkiewicz trace), and a guard set containing the resources granted to the process for its further development. A process concatenation is then defined, which allows independent actions to execute concurrently. Specification refinement leads to a natural approximation ordering between processes. It confers to the set of all processes the structure of a coherently complete prime algebraic Scott domain, whereby, process concatenation is Scott-continuous in both arguments. Furthermore, we define a natural ultrametric on processes based on prefix information. The induced topology is shown to be equivalent to the compact Lawson topology induced by the approximation ordering. Process concatenation is moreover shown to be uniformly continuous with respect to the defined ultrametric. The mathematical theory we develop thus extends the central order and metric properties of the domain of partially terminated finite and infinite words which are needed in order to devise truly concurrent semantics for process algebras much in the style of classical CSP semantics.