Stimuli-Responsive and Electrically Conductive Metal-Organic Frameworks

Metal-organic frameworks (MOFs), a class of porous materials made of organic ligands linked by metal ions or cluster nodes, are well known for their highly ordered crystalline structure and chemical and structural tunability. Due to their porous nature, MOFs can encapsulate guest molecules inside the cavities. The tunable structures, compositions, porosity, and surface area make MOFs useful for various applications, such as gas storage and separation, chemical sensing, catalysis, optoelectronics, and drug delivery. In chapter 2, I present a new luminescent metal-organic framework (LMOF) featuring energy transfer and stimuli (Hg2+) responsive capabilities. The two fluorophoric ligands incorporated in the LMOF framework have complementary absorption and emission, which allows ligand-to-ligand energy transfer. Therefore, upon excitation, the donor transfers the excitation energy to the acceptor chromophore via Fӧrster resonance energy transfer (FRET), and as a result, the MOF emission stemmed from the lower energy emitter (acceptor chromophore). In addition to this, our MOF displayed significant red-shift and quenching of its photoluminescence in the presence of Hg2+ solution while only a modest fluorescence quenching but no spectral shifts in the presence of other transition metal ions. Moreover, the framework structure remained intact after exposure to Hg2+ and other transition metal ions, and its original photoluminescence spectrum could be restored by simple washing, making it a promising reusable Hg2+ sensor. These studies demonstrate the light-harvesting and toxic Hg2+ sensing capabilities of a new luminescent MOF. Chapter 3 focuses on the tuning of the optical and electrical bandgap of a MOF-74 analog. The MOF-74 was constructed from an electron-deficient naphthalene diimide-based ligand containing two salicylic acid groups to coordinate with Zn2+ metal ion. To tune the bandgap of this MOF-74, an electron-rich guest (tetrathiafulvalene; TTF) guests are encapsulated along the wall of the framework. This arrangement of the TTF in the framework increases the electron delocalization via π-π stacking, resulting in the reduction of the bandgap of the MOF by approximately 1 eV. Studies presented in chapter 4 investigate the improvement of the electrical conductivity of an insulating MOF by introducing conductive polymers inside the MOF cavities. In this study, the MOF was loaded with the monomers (EDOT and Py) of the respective conductive polymers (PEDOT and PPy), and polymerization was carried out in the presence of an oxidant (iodine). The resulting MOF-polymer composites exhibit a significantly higher conductivity in comparison to the pristine insulating MOF

Indirect searches of Galactic diffuse dark matter in INO-MagICAL detector

The signatures for the existence of dark matter are revealed only through its gravitational interaction. Theoretical arguments support that the Weakly Interacting Massive Particle (WIMP) can be a class of dark matter and it can annihilate and/or decay to Standard Model particles, among which neutrino is a favorable candidate. We show that the proposed 50 kt Magnetized Iron CALorimeter (MagICAL) detector under the India-based Neutrino Observatory (INO) project can play an important role in the indirect searches of Galactic diffuse dark matter in the neutrino and antineutrino mode separately. We present the sensitivity of 500 kt$\cdot$yr MagICAL detector to set limits on the velocity-averaged self-annihilation cross-section ($\langle\sigma v\rangle$) and decay lifetime ($\tau$) of dark matter having mass in the range of 2 GeV $\leq m_\chi \leq$ 90 GeV and 4 GeV $\leq m_\chi \leq$ 180 GeV respectively, assuming no excess over the conventional atmospheric neutrino and antineutrino fluxes at the INO site. Our limits for low mass dark matter constrain the parameter space which has not been explored before. We show that MagICAL will be able to set competitive constraints, $\langle\sigma v\rangle\leq 1.87\,\times\,10^{-24}$ cm$^3$ s$^{-1}$ for $\chi\chi\rightarrow\nu\bar\nu$ and $\tau\geq 4.8\,\times\,10^{24}$ s for $\chi\rightarrow\nu\bar\nu$ at 90$\%$ C.L. (1 d.o.f.) for $m_\chi$ = 10 GeV assuming the NFW as dark matter density profile.Comment: 28 pages, 22 pdf figures. Discussions & references added. Fig. 9 replaced with new figure for better understanding. Accepted in JHE

The Relationship Between Breast Self-Examination Efficacy and Breast Self-Examination Practice Among Staff Nurses, Bangladesh

Thesis (M.N.S., Nursing Science)-- Prince of Songkla University, 201

Can INO be Sensitive to Flavor-Dependent Long-Range Forces?

Flavor-dependent long-range leptonic forces mediated by the ultra-light and neutral bosons associated with gauged $L_e-L_\mu$ or $L_e-L_\tau$ symmetry constitute a minimal extension of the Standard Model. In presence of these new anomaly free abelian symmetries, the SM remains invariant and renormalizable, and can lead to interesting phenomenological consequences. For an example, the electrons inside the Sun can generate a flavor-dependent long-range potential at the Earth surface, which can enhance $\nu_\mu$ and $\bar\nu_\mu$ survival probabilities over a wide range of energies and baselines in atmospheric neutrino experiments. In this paper, we explore in detail the possible impacts of these long-range flavor-diagonal neutral current interactions due to $L_e-L_\mu$ and $L_e-L_\tau$ symmetries (one at-a-time) in the context of proposed 50 kt magnetized ICAL detector at INO. Combining the information on muon momentum and hadron energy on an event-by-event basis, ICAL can place stringent constraints on the effective gauge coupling $\alpha_{e\mu/e\tau}<1.2\times 10^{-53}$ ($1.75\times 10^{-53}$) at 90$\%$ (3$\sigma$) C.L. with 500 kt$\cdot$yr exposure. The 90$\%$ C.L. limit on $\alpha_{e\mu}$ ($\alpha_{e\tau}$) from ICAL is $\sim 46$ (53) times better than the existing bound from the Super-Kamiokande experiment.Comment: 26 pages, 30 pdf figures, 2 table

“Islamic Moderation” in Perspectives: A Comparison Between Oriental and Occidental Scholarships

‘Islamic moderation’ has received a great deal of academic and media attention both in the West and in the East. Yet, the denotation of the very term still remains abundantly paradoxical as different regions and contexts provide different sheds of meanings. In the western scholarship, Islamic moderation is concerned with liberal social norms, hermeneutics, political pluralism, democratic process, organizational affinities, and views of state legitimacy over the monopoly of violence, some kind of adaptation, willingness to cooperate or compromise. However, it is by no means exhaustive as its definition in Islamic scholarship provides some unlike constituents. To define moderation, Muslim scholars, firstly explores to lexical meanings of its Arabic substitute “wasatiyyah”. Secondly, they explore the textual meanings of the word “wasatiyyah” used in the orthodox text i.e the Quran and traditions (Sunnah) of the Prophet Muhammad (pbuh). According to them, moderation is a best suited, justly balanced or middle position between two extremes i.e. extremism and laxity. Their use of the term, is contextualized in terms of counter-extremism, modest socio-religious behaviour and temperate legal position. This research finds out a considerable textual and contextual difference in the use of the term ‘Islamic moderation’ between the East and the West. Hence, this study aims to explore the lack of integration between both scholarships in this issue.

Ta’dīb and its implementation in children’s education, an analytical study from the prophetic hadīth

The study aims to explore the concept of the ta’dīb (discipline) of children and the way parents and teachers discipline children from the perspective of Sunnah. It attempts to examine the social structure of muslim families, which instils in children some Islamic values and traditional standards. It is agreed that this violent approach does not align with Prophet Muhammad’s approach to disciplining children. It employs inductive and analytical methodologies in which relevant data is collected from Sunnah books (Kutub Sittah) to guide the ta’dīb concept and its application in child education. However, its use in the Sunnah stands unequivocally for discipline. Secondly, corporal punishment has hardly any relevance to the concept of ta’dīb except in exceptional cases. Third, prophetic principles of raising children according to ta’dīb include behavioural modification; developing self-esteem; motivation for seeking knowledge; the impact of naming children; learning through play; self-evaluation; and education through emotional intelligence and compassion. These multiple outcomes are expected to be beneficial in dealing with children’s welfare. Hence, the concept of ta’dīb, if defined and practised properly, can be applied to disciplining children as an Islamic methodology of children’s education, positively and politely

Diet-Induced Overweight Conditions: Effect on Brain Structure, Cognitive Function, and Neurogenesis

Obesity, a chronic condition that is currently prevalent in both developed and developing nations, is associated with pathological features that ultimately put individuals at risk for a number of negative health issues. Cognitive decline and insulin resistance are two aspects of metabolic syndrome that are closely linked to neurological dysfunction during obesity. Several studies suggest that obesity is associated with regional structural changes, especially signs of cortical thinning in specific brain regions like the hippocampus, and reduced microstructural integrity of the white matter tract is associated with an overall lower academic performance. Obesity causes a loss of brain size and volume indicating a loss of neurons which leads to poor cognitive performance and reduced neurogenesis. An increase in the production of free fatty acids seen with HFD eating might result in increased oxidative stress and increased production of reactive oxygen species. The main cause of systemic inflammation in obesity is the build-up of adipose as it releases TNFα, PAI-1, CRP, IL-1β, and IL-6 which contribute to a pro-inflammatory state in the central nervous system. These elements can all lead to the central IKK/NF-B inflammatory signalling cascade being activated, which can cause a vicious inflammatory cycle that quickens and causes neurodegeneration and cognitive decline