Quantum Control of Heat Current

We investigate the local thermal transport in a quantum trimer of harmonic oscillators connected to two thermal baths. The coupling between them are augmented by complex phases which leads to the quantum control of the local atypical heat current between two oscillators connected to the same heat bath. Our study reveals that this atypical heat current is a consequence of the lifting of the dark mode and the modulation of this current is due to variation in system bath correlations. The proposed quantum system may find application in quantum thermal and memory devices by leveraging the heat current

A Rare Presentation of a Common Disease: A Diagnostic Dilemma

Malaria affects millions of people across the globe .The classical clinical features may be absent, but the rapid diagnosis helps in early treatment and thus avoids complications .We present a case of co infection of Plasmodium  vivax and Plasmodium falciparum malaria in a female patient presenting with fever and pain abdomen and incidental detection of splenic infarct .The co infection  is uncommon and treatment should target both to avoid complications . Also,  the exact pathogenesis is un known and though splenic infarct is uncommon and missed due to lack of symptoms , it should be followed up. &nbsp

Donor-Acceptor Oligorotaxanes Made to Order

Five donor–acceptor oligorotaxanes made up of dumbbells composed of tetraethylene glycol chains, interspersed with three and five 1,5-dioxynaphthalene units, and terminated by 2,6-diisopropylphenoxy stoppers, have been prepared by the threading of discrete numbers of cyclobis(paraquat-p-phenylene) rings, followed by a kinetically controlled stoppering protocol that relies on click chemistry. The well-known copper(I)-catalyzed alkyne–azide cycloaddition between azide functions placed at the ends of the polyether chains and alkyne-bearing stopper precursors was employed during the final kinetically controlled template-directed synthesis of the five oligorotaxanes, which were characterized subsequently by ^1H NMR spectroscopy at low temperature (233 K) in deuterated acetonitrile. The secondary structures, as well as the conformations, of the five oligorotaxanes were unraveled by spectroscopic comparison with the dumbbell and ring components. By focusing attention on the changes in chemical shifts of some key probe protons, obtained from a wide range of low-temperature spectra, a picture emerges of a high degree of folding within the thread protons of the dumbbells of four of the five oligorotaxanes—the fifth oligorotaxane represents a control compound in effect— brought about by a combination of C-H···O and π–π stacking interactions between the p-electron-deficient bipyridinium units in the rings and the π-electron-rich 1,5-dioxynaphthalene units and polyether chains in the dumbbells. The secondary structures of a foldamer-like nature have received further support from a solid-state superstructure of a related [3]pseudorotaxane and density functional calculations performed thereon

Radically Enhanced Molecular Switches

The mechanism governing the redox-stimulated switching behavior of a tristable [2]rotaxane consisting of a cyclobis(paraquat-p-phenylene) (CBPQT^4+) ring encircling a dumbbell, containing tetrathiafulvalene (TTF) and 1,5-dioxynaphthalene (DNP) recognition units which are separated from each other along a polyether chain carrying 2,6-diisopropylphenyl stoppers by a 4,4′-bipyridinium (BIPY^2+) unit, is described. The BIPY^2+ unit acts to increase the lifetime of the metastable state coconformation (MSCC) significantly by restricting the shuttling motion of the CBPQTT^4+ ring to such an extent that the MSCC can be isolated in the solid state and is stable for weeks on end. As controls, the redox-induced mechanism of switching of two bistable [2]rotaxanes and one bistable [2]catenane composed of CBPQT^4+ rings encircling dumbbells or macrocyclic polyethers, respectively, that contain a BIPY2+ unit with either a TTF or DNP unit, is investigated. Variable scan-rate cyclic voltammetry and digital simulations of the tristable and bistable [2]rotaxanes and [2]catenane reveal a mechanism which involves a bisradical state coconformation (BRCC) in which only one of the BIPY^•+ units in the CBPQT^2(•+) ring is oxidized to the BIPY2+ dication. This observation of the BRCC was further confirmed by theoretical calculations as well as by X-ray crystallography of the [2]catenane in its bisradical tetracationic redox state. It is evident that the incorporation of a kinetic barrier between the donor recognition units in the tristable [2]rotaxane can prolong the lifetime and stability of the MSCC, an observation which augurs well for the development of nonvolatile molecular flash memory devices

Amphiphilic dendrimers and homopolymers: Self-assembling systems by controlling the structure at the molecular level

The process of self-assembly provides unique opportunities for designing novel materials at the nano-scale. The development of such processes involves fine-tuning of chemical structures and effective use of the non-covalent forces that controls such molecules. This thesis discusses a new design of an amphiphilic species that can undergo self-assembly, directed by solvophobic/solvophilic interactions. The building block of the system contains a polar and an apolar unit, embedded within the same monomer. Amphiphilic dendrimers and homopolymers were built on this basic structure. The self-assembly of these macromolecules were studied in solvents of widely different polarities. The biphenyl based dendrimers showed aggregation behavior in the solvents, which was hitherto unknown for those. Along with their host-guest properties in solution, the preferential location of the amphiphilic functionalities were probed, in order to fundamentally understand the dendritic systems. The same design principle, applied to homopolymers also led to the formation of micelle-like and inverted micelle-like assemblies. The detailed characterization of such systems is discussed along with their behavior in a heterogeneous solvent mixture. The polymeric systems hold promise in applications such as separation nanotechnology and protein sensing

Assessing the modifiable and non-modifiable risk factors associated with multimorbidity in reproductive aged women in India

Abstract Background Reproductive span is the foundation of every woman’s health in later life. India is currently facing a growing burden of multiple morbidities among the women in their reproductive age group which may further increase over the coming decades. The purpose of the present study aimed to identify different modifiable and non-modifiable risk factors affecting multimorbidity among the women in reproductive age group in Indian context. Methods Secondary data were obtained from the Demography and Health Survey (DHS), conducted in India during 2019–2021. A total of 671,967 women aged 15–49 years were selected for this present study. Descriptive, association studies and multinominal logistic regression analyses were performed to accomplish the objectives. Results Currently, 6.3% of total study participant’s reproductive age group women suffered from multimorbidity in India. Never consuming protein, fruits, vegetables and milk increase the chances of developing multimorbidity. Consumption of fried foods, aerated drinks and addiction towards tobacco and alcohol also has a greater influence on the prevalence of multimorbidity. The prevalence of multimorbidity is sharply increased with increasing age and Body Mass Index (BMI). Regionally, the prevalence of multimorbidity was found more among the women hailed from eastern and north-eastern India. Conclusion To reduce the risk of developing multimorbidity, targeted interventions are needed in the form of educating every woman concerning the importance of having minimum health-related knowledge, maintaining healthy lifestyle, weight management and having proper and balanced diet

Synthesizing the risk of morbidities and lifestyle factors on insomnia symptoms among middle-aged and older adult persons in India

Abstract Purpose Most of the time increasing age and improper lifestyle enhance the burgeoning health challenge for middle-aged and older adult persons. In this way, the present study seeks to know the association of morbidity, lifestyle parameters, and background characteristics with insomnia symptoms among middle-aged and older adults in India. Methods The study utilizes a sample of 46,462 older individuals aged 45 years and above from LASI wave-1. Multivariate binary logistic models were applied to acquire the results. Result Insomnia symptom was closely linked with hypertension [AOR: 1.33; 1.27–1.39], heart diseases [AOR: 1.37; 1.23–1.53], the neurological problem [AOR: 1.67; 1.46–1.91], as compared to older adults who did not suffer from any morbidity. The likelihood of insomnia symptoms was also higher among older individuals who reported following an accustomed lifestyle i.e., no reading habit [AOR: 1.35; 1.26–1.45], never going to the park for relaxing leisure hours [AOR: 1.38; 1.01–1.73]. Moreover, insomnia increases with age, and among elder women. Conclusion The encouragement of remedies for morbidity and improper lifestyle practices could be considered as part of a plan to decrease insomnia symptoms. As well as the detection of early stages of insomnia by health professionals and intervention of public health services is necessary

Electrostatic Barriers in Rotaxanes and Pseudorotaxanes

The ability to control the kinetic barriers governing the relative motions of the components in mechanically interlocked molecules is important for future applications of these compounds in molecular electronic devices. In this Full Paper, we demonstrate that bipyridinium (BIPY^(2+)) dications fulfill the role as effective electrostatic barriers for controlling the shuttling and threading behavior for rotaxanes and pseudorotaxanes in aqueous environments. A degenerate [2]rotaxane, composed of two 1,5-dioxynaphthalene (DNP) units flanking a central BIPY^(2+) unit in the dumbbell component and encircled by the cyclobis(paraquat-p-phenylene) (CBPQT^(4+)) tetracationic cyclophane, has been synthesized employing a threading-followed-by-stoppering approach. Variable-temperature ^(1)H  NMR spectroscopy reveals that the barrier to shuttling of the CBPQT^(4+) ring over the central BIPY2+ unit is in excess of 17 kcal mol^(−1) at 343 K. Further information about the nature of the BIPY^(2+) unit as an electrostatic barrier was gleaned from related supramolecular systems, utilizing two threads composed of either two DNP units flanking a central BIPY^(2+) moiety or a central DNP unit flanked by a BIPY2+ moiety. The threading and dethreading processes of the CBPQT^(4+) ring with these compounds, which were investigated by spectrophotometric techniques, reveal that the BIPY^(2+) unit is responsible for affecting both the thermodynamics and kinetics of pseudorotaxane formation by means of an intramolecular self-folding (through donor–acceptor interactions with the DNP unit), in addition to Coulombic repulsion. In particular, the free energy barrier to threading (Δequation image) of the CBPQT^(4+) for the case of the thread composed of a DNP flanked by two BIPY^(2+) units was found to be as high as 21.7 kcal mol^(−1) at room temperature. These results demonstrate that we can effectively employ the BIPY^(2+) unit to serve as electrostatic barriers in water in order to gain control over the motions of the CBPQT^(4+) ring in both mechanically interlocked and supramolecular systems

A general synthesis of macrocyclic p-electron-acceptor systems

Cyclocondensations of aromatic diamines with 1,1'-bis(2,4-dinitrophenyl)-4,4'-bipyridinium salts afford doubly or quadruply charged, macrocyclic, N,N'-diarylbipyridinium cations. These are tolerant of a wide range of acids, bases, and nucleophiles, although they appear to undergo reversible, one-electron reduction by tertiary amines. Single-crystal X-ray analysis demonstrates the presence of a macrocycle conformation in which the 4,4'-bipyridinium and 4,4'-biphenylenedisulfonyl residues are suitably spaced and aligned for complexation with p-donor arenes, and NMR studies in solution indeed confirm binding to 1,5-bis[hydroxy(ethoxy)ethoxy]naphthalene