The Beauty of Twist-Bend Nematic Phase: Fast Switching Domains, First Order Fréedericksz Transition and a Hierarchy of Structures

The twist-bend nematic phase (NTB) exhibits a complicated hierarchy of structures responsible for several intriguing properties presented here. These are: the observation of a fast electrooptic response, the exhibition of a large electroclinic effect, and the observation of an unusual pattern of the temperature dependence of birefringence of bent-shaped bimesogens in parallel-rubbed planar-aligned cells. These unusual effects inspired the use of highly sophisticated techniques that led to the discovery of the twist-bend nematic phase. Results of the optical retardation of a parallel-rubbed planar-aligned cell show that the ‘heliconical angle’ (the angle the local director makes with the optical axis) starts increasing in the high temperature N phase, it exhibits a jump at the N–NTB transition temperature and continues to increase in magnitude with a further reduction in temperature. The liquid crystalline parallel-rubbed planar-aligned and twist-aligned cells in this phase exhibit fascinating phenomena such as a demonstration of the beautiful stripes and dependence of their periodicity on temperature. The Fréedericksz transition in the NTB phase is found to be of the first order both in rubbed planar and homeotropic-aligned cells, in contrast to the second order transition exhibited by a conventional nematic phase. This transition shows a significant hysteresis as well as an abrupt change in the orientation of the director as a function of the applied electric field. Hierarchical structures are revealed using the technique of polymer templating the structure of the liquid crystalline phase of interest, and imaging of the resulting structure by scanning electron microscopy.

Structure, adaptability and security of an architectural object

The paper is devoted to the improvement of the modern methodological apparatus for describing and modeling the structure of architectural objects, which is focused on current trends in the design of buildings and structures with a certain degree of variability and adaptability to rapidly changing modern requirements of potential and real users and external environmental conditions (natural, man-made). In addition, the complexity and variability of the structure of architectural objects directly affect the increase in their operational characteristics, the improvement of security systems and the hierarchy of structures of spaces of different access levels. Another aspect of this problem is the creation of a scientific basis for the formation of a more flexible regulatory framework in architecture.

Dynamic chromatin organization in the cell

The organization and regulation of genomic DNA as nuclear chromatin is necessary for proper DNA function inside living eukaryotic cells. While this has been extensively explored, no true consensus is currently reached regarding the exact mechanism of chromatin organization. The traditional view has assumed that the DNA is packaged into a hierarchy of structures inside the nucleus based on the regular 30-nm chromatin fiber. This is currently being challenged by the fluid-like model of the chromatin which views the chromatin as a dynamic structure based on the irregular 10-nm fiber. In this review, we focus on the recent progress in chromatin structure elucidation highlighting the paradigm shift in chromatin folding mechanism from the classical textbook perspective of the regularly folded chromatin to the more dynamic fluid-like perspective.

Interrelation of Hierarchy of Structures at Comparison of Linear and Cross-linked Polymer Compounds

The comparison of behavior of a linear polymer compounds and cross-linked networks are carried out. It is shown, that the correspondence between rheological behavior of a linear polymer compound and macroscopic behavior of its cross-linked analog is determined by topology of structures describing a hydrogel as qualitatively new object as well as by the type of polymer – solvent interactions. In this situation swelling degree is completely described by the Katchalsky – Lifson’s theory. Moreover it is possible to predict microscopic behavior of macromolecular chains on the base of experimental studies of macroscopic specimens of the gel. Such investigations may be carried out in direct way for organogels. When the gel is charged (polyelectrolyte effect takes place) it is necessary to make some correction. The fact is due to so called effect of concentration redistribution, which occurs when surface of the gel acts as a membrane. In such situation the concentration of low-molecular salt inside gel may be quite more low then the concentration of the salt outside specimen. Thus in the solutions of ionogenic salts real behavior of the specimen is determined not average concentration of salt, but the real concentration of salt inside of the gel. Measuring this concentration experimentally it is possible to carried out investigations of charged macromolecular chains on the base of macroscopic specimens too.

Performance Analysis of FET-Based Nanoiosensors by Computational Method

Human body has a hierarchy of structures. There are many organs which are affected much earlier by a disease when it is detected. Most modern sensors can detect anomalies when its concentration in the body fluid reaches to millimolar range. But more sensitive biosensors should detect disease from much lower concentration like femtomolar range. So, extremely sensitive biosensors are needed for early detection of fatal diseases at their early stage. It should detect the target molecule from a very low concentration of analyte. Also, molecules which we often need to detect are too small in size. So Nanotechnology and biotechnology should shake hand to detect nanosized particles from an extremely low concentration solution. Hence we are in a real need of a biosensor. Here we are interested in charged biomolecules and will discuss the performance of Field- Effect Transistor based biosensosrs by computational method.

Thermal and electro-thermal modeling of components and systems: A review of the research at the University of Parma

paper reviews the activity carried out at the Department of Information Engineering of the University of Parma, Italy, in the field of thermal and electro-thermal modeling of devices, device and package assemblies, circuits, and systems encompassing active boards and heat-sinking elements. This activity includes: (i) Finite-Element 3D simulation for the thermal analysis of a hierarchy of structures ranging from bare device dies to complex systems including active and passive devices, boards, metallizations, and air- and water-cooled heat-sinks, and (ii) Lumped-Element thermal or electro-thermal models of bare and packaged devices, ranging from purely empirical to strictly physics- and geometry-based.

Spiritual Experiences: A Quantitative-Phenomenological Approach

This essay concerns the specific benefits for empirical theology of hybrid quantitative-phenomenological approaches to the scientific study of spiritual experiences. These benefits are conveyed through the consideration of several quantitative techniques newly emerging at the current time. One such technique is the generation of multi-dimensional profiles of individual spirituality, which helps manage the semantic vagueness surrounding the word “spirituality” and thereby yields empirically more robust constructs for use in scientific research studies. Another technique is the creation of quantitative phenomenological signatures of recalled spiritual experiences that penetrate as deeply as possible into the neuropsychological hierarchy of structures, subject to what can be made accessible to human conscious awareness. By hewing close to the shared biological nature of our species’ emotional and cognitive capacities, this type of quantitative phenomenology generates a number of breakthroughs in the scientific study of spiritual experiences. These breakthroughs apply to areas such as developing neuropsychological models of spiritual experiences, studying spiritual experiences cross-culturally, stabilizing descriptive classifications of spiritual experiences, and rendering more exact the experimental study of spiritual experiences. For theologians, there can be no question of the scientific study of spiritual experiences proving or disproving extant theological interpretations. Rather, the theological payoff of quantifying spirituality is the generation of constraints that can render characteristically normative theological interpretations more and less plausible. This underlines the fundamental contention of this essay: that empirical theology requires a partnership in which the importance of distinctively theological questions is respected and the value of empirically derived constraints is prized.