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Energy is the driving force for automation, modernization and economic development where the uninterrupted energy supply is one of the major challenges in the modern world. To ensure that energy supply, the world highly depends on the fossil fuels that made the environment vulnerable inducing pollution in it. Latent heat thermal energy storage (LHTES) systems are very potent to address the environmental issues fostering sustainable development, while being able to provide a secured and uninterrupted power supply at the same time. Renewable energy resources are using widely as sources of energy, but the unreliable and low-density technique of energy storage remains a major challenge. At present, thermal energy storage systems are being used widely because of the greater energy storage densities compared to similar other techniques. This paper overviews the current energy scenarios, environmental impact and the global prospects as well as challenges of LHTES. A review of the technologies can provide a base for strategic energy policy for the next generation of sustainable energy policies and helps policymakers to frame strategies aiming for clean technology and sustainable development. LHTES-based systems are found to be the one of the most suitable technologies for energy storage systems.

Sodium tungstate reacted with tetramethyl- and tetrabutyl-phosphonium bromide in presence of hydrochloric acid to afford two new phosphonium hexatungstate compounds ((CH3)4P)2W6O19, 1, and ((CH3CH2CH2CH2)4P)2W6O19, 2, respectively. Under similar conditions, sodium tungstate reacted with methyltriphenyl-, allyltriphenyl-, butyltriphenyl- and benzyltriphenyl-phosphonium bromides to yield four new phosphonium hexatungstate compounds (CH3Ph3P)2W6O19, 3, (CH2CHCH2Ph3P)2W6O19, 4, (CH3CH2CH2CH2Ph3P)2W6O19, 5, and (C6H5CH2Ph3P)2W6O19, 6, respectively. All six compounds appeared to be stable in air, and were structurally characterized by a combination of FTIR, elemental analyses, and single-crystal X-ray diffraction analyses. The steric effect of the phosphonium cation was investigated and found to cause no significant change on the average bond distances of the hexatungstate anion. The crystal structure analyses of these compounds showed that hexatungstate anions were isolated and the distance between the anions increases with increase in the bulkiness of the surrounding phosphonium cations. Moreover, thermal stability and heat absorption of all six compounds were evaluated using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC).

The purpose of this review article is to discuss the potential of T-type voltage gated calcium channels (VGCCs) as drug targets in breast cancer. Breast cancer, attributable to the different molecular subtypes, has a crucial need for therapeutic strategies to counter the mortality rate. VGCCs play an important role in regulating cytosolic free calcium levels which regulate cellular processes like tumorigenesis and cancer progression. In the last decade, T-type VGCCs have been investigated in breast cancer proliferation. Calcium channel blockers, in general, have shown an anti-proliferative and cytotoxic effects. T-type VGCC antagonists have shown growth inhibition owing to the inhibition of CaV3.2 isoform. CaV3.1 isoform has been indicated as a tumour-suppressor gene candidate and is reported to support anti-proliferative and apoptotic activity in breast cancer. The distribution of T-type VGCC isoforms in different breast cancer molecular subtypes is diverse and needs to be further investigated. The role of T-type VGCCs in breast cancer migration, metastasis and more importantly in epithelial to mesenchymal transition (EMT) is yet to be elucidated. In addition, interlaced therapy, using a combination of chemotherapy drugs and T-type VGCC blockers, presents a promising therapeutic approach for breast cancer but more validation and clinical trials are needed. Also, for investigating the potential of T-type VGCC blocker therapy, there is a need for isoform-specific agonists/antagonists to define and discover roles of T-type VGCC specific isoforms. Our article provides a review of the role of T-type VGCCs in breast cancer and also discusses future of the research in this area so that it can be ascertained whether there is any potential of T-type VGCCs as drug targets in breast cancer.

A fully self-consistent method for solution of the Schrodinger---Poisson equation is presented for III-nitride quantum cascade structures (QCSs). The impact of internal polarization fields on the band structure is incorporated through the coupled Schrodinger---Poisson equation with proper boundary conditions. The method is validated by comparison of the results with reported values for various QCSs. The absorption coefficient for a QCS is obtained and detailed theoretical analysis of the absorption spectrum performed. The influences of temperature, electric field, and active-layer doping on the absorption coefficient were examined. Devices with III-nitride heterostructures show some superior characteristics due to the presence of strong internal polarization fields. It is observed that system doping and temperature do not change the peak absorption wavelength significantly, which is very helpful for operation of high-performance and high-temperature devices. The operating wavelength of the device can be tuned slightly by variation of the external bias voltage.

The effects of temperature and the electric field on the characteristics of a quantum cascade laser (QCL) have been investigated theoretically. A complete three level rate equation model considering all the scattering events has been proposed. The analytical expression for the threshold current density has been derived and the effects of temperature and the electric field are examined. The rate equation model is further used to analyze the population and photon number dynamics present within the cavity of a QCL and the effects of temperature and the electric field on the laser dynamics are investigated numerically.