Performance of some Limiters on the Higher Order Computation of Inviscid Hypersonic Flows

The Advection Upstream Splitting Method (AUSM) is used to compute 2D inviscid hypersonic flow over a semi-cylinder on a finite volume framework. Solution reconstruction to achieve higher order accuracy is done using the MUSCL-type reconstruction technique with the Van Albada and Hemker-Koren limiter functions. The gas models under consideration are the perfect gas model and the high temperature equilibrium chemically reacting air model of Tannehill and Mugge. The performance of these limiters in computing hypersonic flows is analyzed and compared with the first order accurate method.Keywords:Hypersonic, shock, reconstruction, limite

Unravelling The Beauty Of Mathematical Science: Exploring The Intricacies Of Calculus, Algebra, And Geometry

Mathematics, often referred to as the universal language of science, holds a unique allure that transcends cultural and linguistic boundaries. This paper delves into the multifaceted world of mathematics, specifically focusing on the elegance and complexity of three foundational branches: Calculus, Algebra, and Geometry. These mathematical disciplines are not only critical tools for scientific and technological advancements but also fascinating in their own right. Calculus, a cornerstone of modern mathematics, provides a framework for understanding change and motion. It enables us to grasp the concept of infinity and infinitesimal, ultimately unveiling the secrets of the universe's dynamics. Algebra embodies the art of abstract manipulation, offering a systematic approach to problem-solving. Geometry explores the visually compelling properties of shapes and spaces, making the abstract tangible. The journey undertaken in this paper seeks to reveal the inherent beauty within the complexities of these three interconnected mathematical branches that continue to shape the foundations of science, technology, and engineerin

Climate Change, Health and Mosquito-Borne Diseases: Trends and Implications to the Pacific Region.

Climate change is known to affect Pacific Island nations in a variety of ways. One of them is by increasing the vulnerability of human health induced by various climate change impacts, which pose an additional burden to the already distressed health systems in the region. This paper explores the associations between climate change and human health on the one hand, and outlines some of the health care challenges posed by a changing climate on the other. In particular, it describes the links between climate variations and the emergence of climate-sensitive infectious diseases, such as the mosquito-borne diseases dengue, chikungunya, and Zika. The paper also presents a summary of the key findings of the research initiatives Climate Change and Prevalence Study of ZIKA Virus Diseases in Fiji and the findings from the World Mosquito Program as two examples of public health action in the Pacific region

Charge-Assisted Complexation of Anions of Different Dimensionality by Benzimidazole-Based Receptors Bearing -OH Functionality

Two benzimidazole-based receptors (L¹ and L²) bearing -OH functionality form crystalline salts with different organic and inorganic acids viz. [L¹H⁺]­[Cl^–] (<b>1</b>), [L¹H⁺]­[NO₃^–] (<b>2</b>), [L¹H⁺]­[OAc^–] (<b>3</b>), [L¹H⁺]­[DNB^–]·DMF (<b>4</b>), [L¹H⁺]­[H₂PO₄^–] (<b>5</b>), [L²H⁺]­[OAc^–]·AcOH (<b>6</b>), [L²H⁺]­[DNB^–] (<b>7</b>), and [L²H⁺]­[HSO₄^–]·H₂O (<b>8</b>) where the shape of the counteranion drives the solid structure from a one-dimensional polymeric chain to a three-dimensional structure. Structural analyses show that the anion binding in all eight complexes is attributable entirely to NH⁺<b>···</b>anion, NH<b>···</b>anion, OH<b>···</b>anion, and multiple CH<b>···</b>anion hydrogen bonding interactions. In the solid structure the planar nitrate anion forms a cyclic structure with receptor L¹, whereas the acetate anion with the same receptor leads to a molecular barrel type structure. Again the tetrahedral dihydrogen phosphate anion forms a polymeric interanionic chain structure with L¹, and the other tetrahedral hydrogen sulfate anion forms hydrogen sulfate–(water)₂–hydrogen sulfate adducts with charged L²

Charge-Assisted Complexation of Anions of Different Dimensionality by Benzimidazole-Based Receptors Bearing -OH Functionality

Two benzimidazole-based receptors (L¹ and L²) bearing -OH functionality form crystalline salts with different organic and inorganic acids viz. [L¹H⁺]­[Cl^–] (<b>1</b>), [L¹H⁺]­[NO₃^–] (<b>2</b>), [L¹H⁺]­[OAc^–] (<b>3</b>), [L¹H⁺]­[DNB^–]·DMF (<b>4</b>), [L¹H⁺]­[H₂PO₄^–] (<b>5</b>), [L²H⁺]­[OAc^–]·AcOH (<b>6</b>), [L²H⁺]­[DNB^–] (<b>7</b>), and [L²H⁺]­[HSO₄^–]·H₂O (<b>8</b>) where the shape of the counteranion drives the solid structure from a one-dimensional polymeric chain to a three-dimensional structure. Structural analyses show that the anion binding in all eight complexes is attributable entirely to NH⁺<b>···</b>anion, NH<b>···</b>anion, OH<b>···</b>anion, and multiple CH<b>···</b>anion hydrogen bonding interactions. In the solid structure the planar nitrate anion forms a cyclic structure with receptor L¹, whereas the acetate anion with the same receptor leads to a molecular barrel type structure. Again the tetrahedral dihydrogen phosphate anion forms a polymeric interanionic chain structure with L¹, and the other tetrahedral hydrogen sulfate anion forms hydrogen sulfate–(water)₂–hydrogen sulfate adducts with charged L²

Competitive anion binding aptitude of benzimidazole and amide functionality of a non-symmetrical receptor in solid state and solution phase

<p>A novel non-symmetric tripodal receptor (<b>L</b>) with benzimidazole and amide –NH functionalities has been synthesised and a comparative study for anion binding aptitude of those functionalities has been performed in solid state and solution phase. The protonated receptors in solid state tend to form a pseudo-cavity around the octahedral hexafluorosilicate anion whilst in second complex, binding of one sulphate and two bisulphates in unison by two protonated units arises. The benzimidazole –NHs are the strongest hydrogen bond donors in both the crystals controlling dominance over amide –NHs. The neutral receptor being selective towards fluoride anion induces a naked eye visible colorimetric change. The ¹H NMR studies with the neutral and protonated form of the receptor suggest the strong involvement of amide –NH in anion binding in solution phase.</p

Bird Assemblages in a Peri-Urban Landscape in Eastern India

Urbanization plays an important role in biodiversity loss across the globe due to natural habitat loss in the form of landscape conversion and habitat fragmentation on which species depend. To study the bird diversity in the peri-urban landscape, we surveyed four habitats—residential areas, cropland, water bodies, and sal forest; three seasons—monsoon, winter, and summer in Baripada, Odisha, India. We surveyed from February 2018 to January 2019 using point counts set along line transects; 8 transects were established with a replication of 18 each. During the survey, 6963 individuals of 117 bird species belonged to 48 families and 98 genera in the study area, whereas cropland showed rich avian diversity. Based on the non-parametric multidimensional scale (NMDS) and one-way ANOVA, bird richness and abundance differed significantly among the habitats. Cropland showed higher species richness than other habitats; however, water bodies showed more abundance than others. The similarity of bird assemblage was greater between residential areas and cropland than forest and water bodies based on similarity indices. Among seasons, we observed the highest bird species richness in winter and the highest similarity of species richness in monsoon and summer. In conclusion, our study reported that agricultural and degraded landscapes like cropland play important roles in conserving bird diversity in peri-urban landscapes. Our findings highlighted and identified the problems that affect the local biodiversity (e.g., birds) in the peri-urban landscape. It can assist the local government in urban planning and habitat management without affecting the local biodiversity, including birds

Aggregation-Induced Emission Active Metal-Free Chemosensing Platform for Highly Selective Turn-On Sensing and Bioimaging of Pyrophosphate Anion

We report the synthesis of a metal-free chemosensor for highly selective sensing of pyrophosphate (PPi) anion in physiological medium. The novel phenylbenzimidazole functionalized imine containing chemosensor (<b>L</b>; [2,6-bis­(((4-(1<i>H</i>-benzo­[d]­imidazol-2-yl)­phenyl)­imino) methyl)-4 methyl phenol]) could sense PPi anion through “turn-on” colorimetric and fluorimetric responses in a very competitive environment. The overall sensing mechanism is based on the aggregation-induced emission (AIE) phenomenon. Moreover, a real time in-field device application was demonstrated by sensing PPi in paper strips coated with <b>L</b>. Interestingly, detection of intracellular PPi ions in model human cells could also be possible by fluorescence microscopic studies without any toxicity to these cells