449 research outputs found
Phonon sidebands of localized excitons in molecular crystals with methyl torsions: Hexamethylbenzene
Fluorescence and phosphorescence phonon sidebands of isotopic mixed hexamethylbenzene crystals at 2°K are presented. The external phonons can be observed separately from the semiâinternal (methyl torsion) ones. The nature of the electronic or vibronic state has observable but not drastic effects on the excitonâphonon coupling function. Likewise, the exciton delocalization is of minor importance to the excitonâphonon function in hexamethylbenzene. The coupling between external and internal vibrations is also weak in this system. The excitonâphonon coupling appears comparable for the optical and acoustic phonons in hexamethylbenzene. The phonon sidebands give some of the phonon singularities of the lowâtemperature crystal.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70173/2/JCPSA6-60-6-2365-1.pd
COMPARATIVE ANALYTICAL STUDY OF SAJALA AND NIRJALA NARIKEL LAVANA
Advancement being the heart of development any science, Ayurveda has been no exception to this. Various basic formulations have been mentioned in the classical texts i.e. Samhitas and quite a few were added later on, by contemporary Acharyas. Lavana Kalpana is one of them. Lavana Kalpana literally denotes any pharmaceutical formulation comprising Lavana i.e. any type of salt along with other herbal ingredients. Narikel Lavana has been advised under the Rogadhikara of Parinaam Shula. Acharyas have explained two separate methods of preparation of Narikel Lavana: Sajala (retaining the water inside coconut) and Nirjala (without coconut water). Nirjala Narikel Lavana has been prepared by using Mahaputa and Sajala Narikel Lavana in Kukkutaputa. Current study is aimed at preparation, standardization and comparative study of Narikel Lavana as per two different references with the help of sophisticated analytical technique, XRF. Other methods of examination of Ayurvedic drug formulations such as organoleptic evaluation, physico- chemical tests are also employed. The differences between these values and variations in the XRF analysis have been elaborated here. Organoleptic evaluation of both the samples shows no difference, whereas minor variations are observed in the physico- chemical parameters. XRF analysis has clearly indicated the different between the elemental composition of both Sajal and Nirjala Narikel Lavana.
R&D results on a CsI-TTGEM based photodetector
The very high momentum particle identification detector proposed for the
ALICE upgrade is a focusing RICH using a C4F10 gaseous radiator. For the
detection of Cherenkov photons, one of the options currently under
investigation is to use a CsI coated Triple-Thick-GEM (CsI-TTGEM) with metallic
or resistive electrodes. We will present results from the laboratory studies as
well as preliminary results of beam tests of a RICH detector prototype
consisting of a CaF2 radiator coupled to a 10x10 cm2 CsI-TTGEM equipped with a
pad readout and GASSIPLEX-based front-end electronics. With such a prototype
the detection of Cherenkov photons simultaneously with minimum ionizing
particles has been achieved for the first time in a stable operation mode
The ÎS-Householder matrices
AbstractLet A,SâMn(C) be given. Suppose that S is nonsingular and Hermitian. Then A is ÎS-orthogonal if AâSA=S. Let uâCn be such that uâSuâ 0. The ÎS-Householder matrix of u is SuâĄI-tuuâS, where t=2uâSu. We show that det Su=-1, so that products of ÎS-Householder matrices have determinant ±1. Let nâ©Ÿ2 and let k be positive integers with kâ©œn. Set LkâĄIkâ-In-k. We show that every ÎLk-orthogonal matrix having determinant ±1 can be written as a product of at most 2n+2 ÎLk-Householder matrices. We also determine the possible Jordan Canonical Forms of products of two ÎLk-Householder matrices
STANDARDIZATION OF TRAILOKYASUNDAR RASA WITH SPECIAL REFERENCE TO RASARATNASAMUCHCHAYA
The imperishable fundamentals of Ayurveda, which were laid down by the great sages of the olden days are still applicable because of their eternal sustainability. These fundamentals need to be time tested through scientific research not only to prove the validity but also to update the existing knowledge. Rasa Shastra, with its blend of mystical and medical insights, is source of valuable knowledge. Rasa aushadhis are appreciated for their Quick efficacy even at small dosages, long durability etc. Trailokyasundar rasa is a Rasakalpa explained in Rasaratnasamucchaya. Little research has been done on this Kalpa and it is not commonly prescribed by the Ayurvedic practitioners and Vaidyas. Considering all the above factors, a step has been taken to develop standard operating procedures (SOP) for preparing Trailokyasundar rasa, in this study. This is an attempt towards standardizing the processes at every stage of preparation of Trailokyasundar rasa (so as to define the SMP) which is exclusively mentioned in Rasaratnasamuchhaya Pandurogadhikara. The final product has been analyzed on the basis of various parameters such as organoleptic characters, physico- chemical properties and XRF testing. The observations recorded through these techniques show that following the classically recommended directions for this Kalpa, results in the final product matching the desired standards.
Functional Association Between Three Archaeal Aminoacyl-tRNA Synthetases
Aminoacyl-tRNA synthetases (aaRSs) are responsible for attaching amino acids to their cognate tRNAs during protein synthesis. In eukaryotes aaRSs are commonly found in multi-enzyme complexes, although the role of these complexes is still not completely clear. Associations between aaRSs have also been reported in archaea, including a complex between prolyl-(ProRS) and leucyl-tRNA synthetases (LeuRS) in Methanothermobacter thermautotrophicus that enhances tRNAPro aminoacylation. Yeast two-hybrid screens suggested that lysyl-tRNA synthetase (LysRS) also associates with LeuRS in M. thermautotrophicus. Co-purification experiments confirmed that LeuRS, LysRS, and ProRS associate in cell-free extracts. LeuRS bound LysRS and ProRS with a comparable KD of about 0.3â0.9 ÎŒm, further supporting the formation of a stable multi-synthetase complex. The steady-state kinetics of aminoacylation by LysRS indicated that LeuRS specifically reduced the Km for tRNALys over 3-fold, with no additional change seen upon the addition of ProRS. No significant changes in aminoacylation by LeuRS or ProRS were observed upon the addition of LysRS. These findings, together with earlier data, indicate the existence of a functional complex of three aminoacyl-tRNA synthetases in archaea in which LeuRS improves the catalytic efficiency of tRNA aminoacylation by both LysRS and ProRS
MiR-133a Mimic Alleviates T1DM-Induced Systolic Dysfunction in Akita: An MRI-Based Study
Diabetic cardiomyopathy is a leading cause of heart failure. Developing a novel therapeutic strategy for diabetic cardiomyopathy and characterizing animal models used for diabetes mellitus (DM) are important. Insulin 2 mutant (Ins2+/-) Akita is a spontaneous, genetic, mouse model for T1DM, which is relevant to humans. There are contrasting reports on systolic dysfunction and pathological remodeling (hypertrophy and fibrosis) in Akita heart. Here, we used magnetic resonance imaging (MRI) approach, a gold standard reference for evaluating cardiac function, to measure ejection fraction (indicator of systolic dysfunction) in Akita. Moreover, we performed Wheat Germ Agglutinin (WGA) and hematoxylin and Eosin stainings to determine cardiac hypertrophy, and Masson\u27s Trichrome and picrosirius red stainings to determine cardiac fibrosis in Akita. MiR-133a, an anti-hypertrophy and anti-fibrosis miRNA, is downregulated in Akita heart. We determined if miR-133a mimic treatment could mitigate systolic dysfunction and remodeling in Akita heart. Our MRI results revealed decreased ejection fraction in Akita as compared to WT and increased ejection fraction in miR-133a mimic-treated Akita. We also found that miR-133a mimic treatment mitigates T1DM-induced cardiac hypertrophy and fibrosis in Akita. We conclude that Akita shows cardiac hypertrophy, fibrosis and systolic dysfunction and miR-133a mimic treatment to Akita could ameliorate them
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