Effect of nano- and micron-sized K0.5Na0.5NbO3 fillers on the dielectric and piezoelectric properties of PVDF composites

Polymer nanocrystal composites were fabricated by embedding polyvinylidene fluoride (PVDF) with K0.5Na0.5NbO3 (KNN) nanocrystallites of different volume fraction using the hot-pressing technique. For comparison, PVDF-KNN microcrystal composites of the same compositions were also fabricated which facilitated the studies of the crystallite size (wide range) effect on the dielectric and piezoelectric properties. The structural, morphological, dielectric, and piezoelectric properties of these nano and micro crystal composites were investigated. The incorporation of KNN fillers in PVDF at both nanometer and micron scales above 10 vol% resulted in the formation of polar beta-form of PVDF. The room temperature dielectric constant as high as 3273 at 100 Hz was obtained for the PVDF comprising 40 vol% KNN nanocrystallites due to dipole-dipole interactions (as the presence of beta-PVDF is prominent), whereas it was only 236 for the PVDF containing the same amount (40 vol%) of micron-sized crystallites of KNN at the same frequency. Various theoretical models were employed to predict the dielectric constants of the PVDF-KNN nano and micro crystal composites. The PVDF comprising 70 vol% micron-sized crystallites of KNN exhibited a d (33) value of 35 pC/N, while the nanocrystal composites of PVDF-KNN did not exhibit any piezoelectric response perhaps due to the unrelieved internal stress within each grain, besides the fact that they have less domain walls

Overview of urban heat island (UHI) phenomenon towards human thermal comfort

Urban Heat Island (UHI) is expected to be a disastrous challenge to human in the following decade as a result of continuous urbanization without appropriate planning and design. The impacts of UHI are even getting worse due to large population density with improper building design especially in dense metropolitan cities. A lot of research has been carried out for UHI phenomenon both in tropical and seasonal climates. There are many factors contributing to the formation of UHI phenomenon that includes increasing rate of urbanization and population density, uncontrollable factors and controllable factors. In a fundamental study, a prolonged exposure to heat impact will significantly contribute to human discomfort and health problems resulting in heat-related illness. The cases of heat related deaths, such as heat strokes, are due to the result of climate changes and further the problem of heat waves will increase year by year. Since the consequences of UHI are considered to be more significant, the severity of the problem should be critically examined and carefully reported. Many research efforts have been implemented for making conceptual design and also a wide range of literature is available for continuing the mitigation strategies. Therefore, this study is emphasized on the critical investigation of the features, factors and impacts of UHI towards evaluating human safety and thermal comfort. Future research direction should also be encompassed on the design and planning parameters as well as assessment of climate change risks and vulnerability for reducing the effects of urban heat island onto human health and safety

Interactions of IgG1 CH2 and CH3 Domains with FcRn

Antibody fragments are emerging as promising biopharmaceuticals because of their relatively small size and other unique properties. However, when compared to full-size antibodies, most of the current antibody fragments of VH or VL display greatly reduced half-lives. A promising approach to overcome this problem is through the development of novel antibody fragments based on IgG Fc region, which contributes to the long half-life of IgG through its unique pH-dependent association with the neonatal Fc receptor (FcRn). The IgG Fc region comprises two CH2 and two CH3 domains. In this report, we present a comparative study of the FcRn binding capability of the CH2 and CH3 domains. The stability and aggregation resistance of these domains were also investigated and compared. We found that monomeric CH2 and CH3 domains exhibited the pH-dependent FcRn binding while the dimeric forms of CH2 and CH3 domains did not. Although all of these domains had high serum stability, they had aggregation tendencies as measured by dynamic light scattering. By providing a better understanding of the structure-activity relationship of the Fc fragment, these results guide further approaches to generate novel Fc-based small-size antibody fragments that possess pH-dependent FcRn binding capability, desired in vivo half-lives and other favorable biophysical properties for their drugability

Reliable multiclass cancer classification of microarray gene expression profiles using an improved wavelet neural network

Properly designing a wavelet neural network (WNN) is crucial for achieving the optimal generalization performance. In this paper, two different approaches were proposed for improving the predictive capability of WNNs. First, the types of activation functions used in the hidden layer of the WNN were varied. Second, the proposed enhanced fuzzy c-means clustering algorithm—specifically, the modified point symmetry-based fuzzy c-means (MSFCM) algorithm—was employed in selecting the locations of the translation vectors of the WNN. The modified WNN was then applied to heterogeneous cancer classification using four different microarray benchmark datasets. The comparative experimental results showed that the proposed methodology achieved an almost 100% classification accuracy in multiclass cancer prediction, leading to superior performance with respect to other clustering algorithms. Subsequently, performance comparisons with other classifiers were made. An assessment analysis showed that this proposed approach outperformed most of the other classifiers

Reproduction in the Female Mithun

Mithun is a domesticated beef bovine species in Himalayan foothills of Southeast Asia. It inhabits at an altitude from 300 to 3000 m MSL, often under extensive grazing system. Mithun is a very fertile animal, able to produce one calf/year. Mithun can interbreed with other bovine species, but male offspring are sterile. This chapter intent is to gather and discuss available information on several aspects of reproduction in female Mithun. The morphology of the reproductive organs is different from cattle and has a longer reproductive tract and pregnancies compared to cattle. Although its estrus period is longer than in cow, Mithun usually displays silent heats, requiring a breeding bull for heat detection. Seasonal fluctuations on reproductive pattern have been reported, which are related to forage availability and quality. Calving in summer takes longer to resumption of cyclic ovarian activity than calving in winter. As Mithun is an important socio-cultural-religious-economic asset in India, to counter some short comings, new breeding strategies have been introduced like multiple ovulation and embryo transfer technology. A good understanding of different aspects of reproduction is crucial to support effective reproductive managements to enhance socio-economic status and cultural importance of tribals to preserve Mithun germplasm to be used in future

PAIR MEAN CORDIAL LABELING OF HURDLE, KEY, LOTUS, AND NECKLACE GRAPHS

Let  be a graph with  vertices and  edges. Define and . Consider a mapping  by assigning different labels in  to the different elements of  when is even and different labels in  to elements of V and repeating a label for the remaining one vertex when  is odd. The labeling as defined above is said to be a pair mean cordial labeling if for each edge  of G, there exists a labeling   if  is even and   if  is odd such that | |≤1 where  and  respectively denote the number of edges labeled with 1 and the number of edges not labeled with 1. A graph G for which there is a pair mean cordial labeling is called pair mean cordial graph(PMC-graph). In this paper, we investigate the pair mean cordial labeling of some graphs like hurdle graph, lotus graph, necklace graph, F-tree, Y-tree, subdivided shell graph, uniform bow graph and key graph

Symbiotic Nitrogen Fixation and the Challenges to Its Extension to Nonlegumes

Access to fixed or available forms of nitrogen limits the productivity of crop plants and thus food production. Nitrogenous fertilizer production currently represents a significant expense for the efficient growth of various crops in the developed world. There are significant potential gains to be had from reducing dependence on nitrogenous fertilizers in agriculture in the developed world and in developing countries, and there is significant interest in research on biological nitrogen fixation and prospects for increasing its importance in an agricultural setting. Biological nitrogen fixation is the conversion of atmospheric N2 to NH3, a form that can be used by plants. However, the process is restricted to bacteria and archaea and does not occur in eukaryotes. Symbiotic nitrogen fixation is part of a mutualistic relationship in which plants provide a niche and fixed carbon to bacteria in exchange for fixed nitrogen. This process is restricted mainly to legumes in agricultural systems, and there is considerable interest in exploring whether similar symbioses can be developed in nonlegumes, which produce the bulk of human food. We are at a juncture at which the fundamental understanding of biological nitrogen fixation has matured to a level that we can think about engineering symbiotic relationships using synthetic biology approaches. This minireview highlights the fundamental advances in our understanding of biological nitrogen fixation in the context of a blueprint for expanding symbiotic nitrogen fixation to a greater diversity of crop plants through synthetic biology.Biotechnology and Biological Sciences Research Council (Great Britain) (Grants BB/L011484/1 and BB/L011476/1)National Science Foundation (U.S.) (Grant 1331098

Difference Cordial Labeling of Graphs Obtained from Triangular Snakes

In this paper, we investigate the difference cordial labeling behavior of corona of triangular snake with the graphs of order one and order two and also corona of alternative triangular snake with the graphs of order one and order two

PMC-LABELING OF SOME CLASSES OF GRAPHS CONTAINING CYCLES

Let be a graph with p vertices and q edges. We have introduced a new graph labeling method using integers and cordial-related works and investigated some graphs for this labeling technique. Using this labeling concept, we have examined the graphs like path, cycle, star, complete graph, comb, and wheel graph. The first research paper on graph theory was published by Leonhard Euler. However, he did not use the word ‘graph’ in his work. In the early stages of the development of the subject, the vertices of a graph were specified as , and the edges were denoted by, . In recent times, several researchers have attempted to provide different types of labeling to the vertices and edges of a graph by identifying the relevant mathematical properties. The present paper provides a novel method of labeling by employing integers, which may form a foundation for future research work. In this paper, we investigate the pair mean cordial labeling behavior of some cycle-related graphs like the ice cream graph, closed web graph, circulant graph, zig-zag chord graph, pentagonal circular ladder, djembe graph, quadrilateral friendship graph, and origami graph