An examination of the therapeutics and diagnostics use of porphyrinoids including phthalocyanines and glycosylated porphyrins is offered. Topics covered include glycosylated phthalocyanines, ...glycosylated chlorins, isobacteriochlorins and bacteriochlorins and glycosylated porphyrazines.
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IJS, KILJ, NUK, PNG, UL, UM
The term "urban heat island" (UHI) refers to a temperature that is greater than the surrounding rural or suburban region. The urban heat factor is directly proportional to the land surface ...temperature. UHI is a much warmer urban region than the neighbouring rural areas. Heat is produced in large cities by the combined energy of all the people, automobiles, buses, and trains. In heat balance research and as a control for climate models, the land surface temperature is an essential component for predicting the radiation budget. In this research, an effort was made to estimate surface temperature across the Almora city region using Landsat-5 and Landsat-8 satellite data. The Lands at visible and Near Infrared (NIR) channels were used to explore the variability of these Land Surface Temperatures (LST) about distinct land use/land cover types. The emissivity per pixel was derived directly from the satellite data and calculated as narrowband emissivity at the satellite sensor channel to reduce the estimation error in surface temperature. The findings imply that the approach may be used to predict the surface temperature and emissivity using the Normalized Difference Vegetation Index (NDVI) with good accuracy in various metropolitan regions.
During autophagy, double-membrane vesicles called autophagosomes capture and degrade the intracellular cargo. The de novo formation of autophagosomes requires several vesicle transport and membrane ...fusion events which are not completely understood. We studied the involvement of exocyst, an octameric tethering complex, which has a primary function in tethering post-Golgi secretory vesicles to plasma membrane, in autophagy. Our findings indicate that not all subunits of exocyst are involved in selective and general autophagy. We show that in the absence of autophagy specific subunits, autophagy arrest is accompanied by accumulation of incomplete autophagosome-like structures. In these mutants, impaired Atg9 trafficking leads to decreased delivery of membrane to the site of autophagosome biogenesis thereby impeding the elongation and completion of the autophagosomes. The subunits of exocyst, which are dispensable for autophagic function, do not associate with the autophagy specific subcomplex of exocyst.
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•A subcomplex of exocyst is involved in autophagosome biogenesis.•Incompletely formed autophagosomes are formed in the absence of functional exocyst.•Autophagosome biogenesis is affected in exocyst mutants due to diminished membrane supply by Atg9 vesicles.•The exocyst subcomplex mediates the Atg9 vesicles tethering at PAS.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•In this paper, a standalone photovoltaic (PV)-battery storage (BS) based microgrid (MG) is presented with a 415V-AC bus. Power generation from renewable energy sources (RESs) is not always ...available; it is necessary to use a BS.•PV array is connected to primary voltage source converter (VSC1) DC-link to achieve maximum power output in a cost-effective and efficient single-stage configuration.•This is achieved through an incremental conductance (INC) maximum power point (MPP) tracking approach.•Moreover, secondary converter (VSC2) is connected to BS for power flow management.•MG performance is evaluated under various operating conditions. Steady-state and dynamic performances of MG are studied for variations such as changes in solar PV irradiance and load unbalances.
In this paper, a standalone photovoltaic (PV)-battery storage (BS) based microgrid (MG) is presented with a 415V-AC bus. The PV array is linked to the main voltage source converter (VSC1) DC-link to maximize power production in an efficient and cost-effective single-stage structure. This is achieved through an incremental conductance (INC) maximum power point (MPP) tracking approach. Moreover, a secondary converter (VSC2) is connected to BS for power flow management. MG performance is evaluated under various operating conditions. Steady-state and dynamic performances of MG are studied for variations such as changes in solar PV irradiance and load unbalances.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study deals with a new control for a double‐stage grid‐integrated solar photovoltaic array (SPVA)‐based energy generation system, which is based on adjoint least mean square (ALMS) control. This ...ALMS control algorithm has some new features: (1) it provides a fast rate of convergence, (2) harmonics mitigation ability, and (3) ease of implementation. The solar PV energy generating system includes a DC–DC boost converter, a voltage source converter (VSC), a ripple filter, a three‐phase grid, and local non‐linear loads. The VSC is controlled for feeding the active power from the solar array to the grid and three‐phase non‐linear loads. Moreover, VSC control is used to improve the grid current quality. A DC–DC boost converter is coupled between the photovoltaic array and the DC‐link capacitor, which tracks the maximum SPVA power from the SPV array by using perturb & observe algorithm. Here, the main goals of SPVA generating system are to eradicate power quality problems caused by unbalanced and non‐linear loads and to provide sinusoidal grid currents at solar PV array irradiance variation. Moreover, a comparison of ALMS control is made with other control algorithms. Performance of this ALMS control is studied at varying non‐linear loads and under different environmental conditions on a developed prototype in the laboratory. The simulated results of the system are validated with test results. Detailed behaviour of the grid‐integrated SPV system and harmonics spectrum of grid currents are given here while meeting the IEEE 519 Standard.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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Herein we describe the design, efficient synthesis, and photophysical properties of two macrocycle dyes for cancer theranostics. This study compares a glycosylated chlorin with a ...glycosylated phthalocyanine designed to specifically target cancer, wherein the photophysical properties enable both fluorescence imaging and the sensitization of the formation of reactive oxygen species (ROS) for photodynamic therapy. Both the compounds show low darktoxicity (IC50 > 100 μM). The glycosylated phthalocyanine showed low phototoxicity (IC50 > 100 μM) while glycosylated chlorin showed high phototoxicity (IC50 = 1–2 μM). ZnPcGlc8 has low solubility and also form aggregates in aqueous media, thus resulting in minimal uptake in two different human breast cancer cell lines: MDA-MB-231 and MCF-7. The glycosylated chlorin however was efficiently taken up by these two cell lines, thus allows fluorescence imaging in cells and in xenograft tumor model in mice. In this study, we find that the chlorin conjugate is the more promising theranostic agent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The photophysical properties of a chlorin, isobacteriochlorin and bacteriochlorin built on a core tetrapentafluorophenylporphyrin (TPPF20) and the nonhydrolyzable para thioglycosylated conjugates of ...these chromophores are presented. The photophysical characterization of these compounds was done in three different solvents to correlate with different environments in cells and tissues. Compared with TPPF20 other dyes have greater absorption in the red region of the visible spectrum and greater fluorescence quantum yields. The excited state lifetimes are from 3 to 11 ns. The radiative and nonradiative rate constants for deactivation of the excited state were estimated from the fluorescence quantum yield and excited state lifetime. The data indicate that the bacteriochlorin has strong absorption bands near 730 nm and efficiently enters the triplet manifold. The isobacteriochlorin has a 40–70% fluorescence quantum yield depending on solvent, so it may be a good fluorescent tag. The isobacteriochlorins also display enhanced two‐photon absorption, thereby allowing the use of 860 nm light to excite the compound. While the two‐photon cross section of 25 GM units is not large, excitation of low chromophore concentrations can induce apoptosis. The glycosylated compounds accumulate in cancer cells and a head and neck squamous carcinoma xenograft tumor model in mice. These compounds are robust to photobleaching.
Click‐type chemistry allows tetraglycosylation of the perfluorophenyl derivatives of a chlorin, bacteriochlorin, and an isobacteriochlorin in high yields. The four non‐hydrolysable sugars target the chromophores to mouse models of head and neck squamous cell carcinoma. Here the glycosylated chlorin allows fluorescence imaging of these tumors.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The facile synthesis and photophysical properties of three nonhydrolyzable thioglycosylated porphyrinoids are reported. Starting from meso-perfluorophenylporphyrin, the nonhydrolyzable ...thioglycosylated porphyrin (PGlc4), chlorin (CGlc4), isobacteriochlorin (IGlc4), and bacteriochlorin (BGlc4) can be made in 2−3 steps. The ability to append a wide range of targeting agents onto the perfluorophenyl moieties, the chemical stability, and the ability to fine-tune the photophysical properties of the chromophores make this a suitable platform for development of biochemical tags, diagnostics, or as photodynamic therapeutic agents. Compared to the porphyrin in phosphate buffered saline, CGlc4 has a markedly greater absorbance of red light near 650 nm and a 6-fold increase in fluorescence quantum yield, whereas IGlc4 has broad Q-bands and a 12-fold increase in fluorescence quantum yield. BGlc4 has a similar fluorescence quantum yield to PGlc4 (<10%), but the lowest-energy absorption/emission peaks of BGlc4 are considerably red-shifted to near 730 nm with a nearly 50-fold greater absorbance, which may allow this conjugate to be an effective PDT agent. The uptake of CGlc4, IGlc4, and BGlc4 derivatives into cells such as human breast cancer cells MDA-MB-231 and K:Molv NIH 3T3 mouse fibroblast cells can be observed at nanomolar concentrations. Photobleaching under these conditions is minimal.
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IJS, KILJ, NUK, PNG, UL, UM
Porphyrins bearing uracyl motifs at the four meso positions self-organize via homo-complementary hydrogen bonds and pi-stacking into nanofibers, nanorods and thin films on mica and glass surfaces ...depending on deposition conditions.
This paper deals with the power quality improvement in a double stage solar photovoltaic (SPV) grid integrated system by an adaptive least mean absolute third (LMAT) control. This topology has ...advantages such as, (1) it has high efficiency, and (2) it provides an enhanced response. This SPV generating system consists of many components such as, a BC (Boost converter), a RC ripple filter, a VSC (Voltage source converter), local loads, and a 3-\Phi grid. Here, the VSC is connected at DC bus for feeding SPV power into the three-phase grid, which is also used to improve the power quality. An adaptive LMAT control estimates the fundamental load components, which provides the fast rate of convergence and less steady state error. The THDs (Total Harmonic Distortions) of grid currents are shown within the limits of the IEEE-519 standard.
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