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De-coherence is the problem in quantum physics wherein the particles essentially lose their quantum properties. De-coherence of quantum states is a major hurdle towards scalable and reliable quantum computing[6]. By reducing de-coherence, the error correction can be alleviated and obviate the need for energy-intensive noise reduction techniques [6]. Through this paper I propose a way to reduce de-coherence obtained due to temperature and magnetic noise in an effective way., {"references":["1.\thttps://en.wikipedia.org/wiki/Quantum_computing#:~:text=Quantum%20computing%20is%20the%20use,are%20known%20as%20quantum%20computers.","2.\thttps://www.sciencedirect.com/science/article/pii/S0004370209001398?via%3Dihub","3.\thttps://en.wikipedia.org/wiki/Quantum_decoherence#:~:text=Quantum%20decoherence%20is%20the%20loss,to%20explain%20various%20quantum%20effects.","4.\thttps://arxiv.org/ftp/cs/papers/0602/0602096.pdf#:~:text=Specifically%2C%20problems%20related%20to%20decoherence,implementability%20of%20gates%20are%20considered.&text=Faster%20speed%20and%20the%20capacity,the%20building%20of%20quantum%20computers.","5.\thttps://arxiv.org/abs/1904.04323","6.\thttps://www.montanainstruments.com/Applications/Quantum-Computing-in-Cryogenic-Systems/","7.\thttps://www.sciencemag.org/news/2018/03/weird-vibrations-poised-control-quantum-computers","8.\thttp://www.mit.edu/~nselby/low-temperature-physics-for-quantum-computing.html","9.\thttps://arxiv.org/ftp/arxiv/papers/1608/1608.06273.pdf","10.\thttps://www.sciencedirect.com/science/article/abs/pii/S1386947707002718","11.\thttps://www.sciencedaily.com/releases/2018/10/181026102557.htm","12.\thttps://www.nature.com/articles/s41534-020-00309-7"]}

From the time we were created, humans have been piqued their interest. Man has always been exploring the outer space for new avenues both solar and extrasolar system planets. There are few factors that need to be analysed and studied. This paper discusses the various factors considered for space exploration

Aim To compare the periodontal status in relation to the lower anteriors of patients between labial and lingual orthodontic therapy. Materials and methods The study includes a total of 20 patients in the age group of 20-30 years. All the included patients were selected with limited lower anterior crowding within 0-8 mm. The subjects were randomly divided into two groups: labial (n=10) and lingual (n=10) fixed orthodontic therapy. The periodontal status was evaluated using three indices, plaque index, calculus index, and gingival index, at two different treatment intervals - the first month and the third month - of orthodontic treatment. Results The values of all the three indices at both time intervals were tabulated. There was no statistical significance when compared to the values in the first month. In the third month, all three indices were statistically significant for both labial and lingual therapy (p

For this study PbTe and PbSe thin films have been prepared on silicon substrates with native oxide by Atomic Layer Deposition (ALD) using lead (II)bis(2,2,6,6-tetramethyl-3,5-heptanedionato) (Pb(C11H19O2)2), (trimethylsilyl) telluride ((Me3Si)2Te) and bis-(triethyl silyl) selane ((Et3Si)2Se) as ALD precursors for lead, tellurium and selenium . Instead of classic layer by layer ALD growth the initial ALD nucleation of lead telluride was found to follow the Vollmer-Weber island growth model. We found a strong dependence of the nucleation process on the temperature. In this project, we present the optimized conditions for growing PbTe and PbSe thin films within the ALD process window range of 170 °C to 210 °C and discuss early nanolaminate structures. Results of various physical characterizations techniques and analysis are reported.

Though intestinal tuberculosis is relatively a common ailment in India and other developing countries; enterolithiasis is a rarely encountered clinical and radiological entity found in this disease. Enteroliths are formed due to stasis caused by stricture formation in intestinal tuberculosis. We report a case of enterolithiasis secondary to intestinal tuberculosis.

Thermoelectric materials have attracted much attention for their potential in conversion between heat and electricity and consequently could be used for heating and cooling systems. The efficiency of a thermoelectric material is expressed by the dimensionless thermoelectric figure of merit, ZT = S2σT/ k, where S is the Seebeck coefficient, σ is the electrical conductivity, and kis the thermal conductivity [1]. Previous work demonstrated alloying was used to decrease the lattice thermal conductivity and thus to increase ZT owning to mass difference enhanced phonon scattering. In order to further progress in the development and commercialization of the next generation of thermoelectric devices it is necessary to enhance the ZT value. Most recently research focused on low dimensional nanostructures, including quantum wells, quantum dots, superlattice, quantum wires and nanolaminates to improve ZT. In superlattice structures, reduced lattice thermal conductivity is mainly due to the phonon scattering at multiple interface boundaries. Significant efforts have been made to investigate the IV-VI semiconducting lead chalcogenides, such as PbTe and PbSe due to their high figure of merit, good chemical stability, low vapor pressure and high melting point. Therefore they are promising thermoelectric materials for intermediate temperature applications ranging from 600 to 800 K. PbTe and PbSe films have been deposited by different techniques, such as pulsed laser deposition (PLD), metal-organic chemical vapor deposition (MO-CVD), magnetron sputtering, molecular beam epitaxy (MBE) and atomic layer deposition (ALD). Among these, ALD is considered as a novel and competitive method to deposit PbTe/PbSe nanolaminate structures. The ALD is a self-limiting atomic layer reaction in each ALD cycle introduce. It can precisely control the film layer thickness, stoichiometry, composition, uniformity, and sharp interface. ALD also can be used to deposit conformal films onto very complex structures. It is possible to generate the reproducible and well-defined nanolaminate structures. Furthermore, the deposition temperature of ALD is rather low in comparison with other growth techniques. In this work we report on the successful synthesis of multiple PbTe/PbSeTe nanolaminates on silicon substrates by a thermal ALD system. In this new nanolaminate structure a very thin layer of the PbSeTe ternary compound is formed by nucleation of PbSe quantum dots between binary PbTe layers, which is followed by an annealing process step. It is noted that the formation of the PbSe quantum dots is facilitated the prevailing Volmer-Weber island growth mode. Lead bis(2,2,6,6-tetramethyl-3,5-heptanedionato) (Pb(C11H19O2)2), (trimethylsilyl) telluride ((Me3Si)2Te) and (trimethylsilyl) selenide ((Me3Si)2Se) were employed as the chemical ALD precursors for lead, telluride and selenide, respectively. 20 sccm N2 was used as a carrier gas to transport the chemical precursors into the ALD reaction chamber. The ALD growth temperature was 170 oC. The solid lead precursor was volatilized at a temperature of 140 oC, the liquid Te precursor required heating to 40 oC, and the liquid Se precursor was kept at room temperature. The chamber base pressure was kept at 30 mTorr. Several physical characterization techniques have been employed to determine the ALD nanolaminate formation. The crystal structure was analyzed by X-ray diffraction (XRD). The film morphology and structure of the products were determined by field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HR-TEM).The surface roughness was analyzed by atomic force microscopy (AFM). The analysis of the composition and stoichiometry of the ternary and binary layers were carried out by X-ray photoelectron spectroscopy (XPS) and Energy dispersive X-ray spectroscopy (EDS). References: K. Zhang, A. D. Ramalingom Pillai, D. Nminibapiel, M. Tangirala, V. S Chakravadhanula, C. Kübelc, H. Baumgart, V. Kochergin, ECS Trans., 58, 10, 131 (2013).

The IV-VI lead chalcogenides are considered as prospective thermoelectric materials which have their potential applications in green renewable energy by waste heat recovery and infrared devices. Among these materials, PbSe demonstrates a remarkable thermoelectric performance, The thermoelectric figure of merit ZT exceeds 1 for both n-type and p-type PbSe at high temperature. ZT is defined as ZT=σS2T/κ, where S is the Seebeck coefficient, σ is the electrical conductivity, and κ is the thermal conductivity, respectively. In addition, Se element is more abandant and less costly than Te which is a scarce element [1]. PbSe thin films on Si substrates have been synthesized by various methods. However, a careful literature search reveals, there are few if any reports on the synthesis of PbSe thin films by atomic layer deposition (ALD). The ALD technique exhibits self-limiting surface reactions in each ALD cycle which consequently results in precise layer thickness control, stoichiometry, composition, uniformity of large area on the substrate. ALD also can be used to deposit conformal film onto very complex substrates or nano-porous template surfaces. This is the one advantageous property of ALD which renders it more competitive and promising in porous template nano-structures. In contrast, magnetron sputtering and PLD cannot be used to coat complex 3D structures with PbSe. Furthermore, the growth temperature of ALD is rather low in comparison with other fabrication processes. In this work we report on the successful synthesis of multiple PbSe thin films on silicon substrates and inside microporous Si templates by thermal ALD, using lead bis(2,2,6,6-tetramethyl-3,5-heptanedionato) (Pb(C11H19O2)2) and (trimethylsilyl) selenide ((Me3Si)2Se) as the chemical ALD precursors for lead and selenide, respectively. The repetitive structure of nano-porous Si templates offers an additional degree of periodicity in the quest for high ZT thermoelectric films. The XRD and FE-SEM results reveal that the Lead selenide thin films are polycrystalline at deposition temperatures of 170 °C based on Volmer Weber Island growth mode and have characteristic FCC rock-salt crystal structure as shown in Figure (1), (2) and (3). References: H. Wang, Z. M. Gibbs, Y. Takigawa, G. J. Snyder, Energy Environ. Sci., 7, 804 (2014).