Artículos de revistas: "Asymmetric top molecule"

1

Coudert, L. H. "Optimal orientation of an asymmetric top molecule with terahertz pulses". Journal of Chemical Physics 146, n.º 2 (14 de enero de 2017): 024303. http://dx.doi.org/10.1063/1.4973773.

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2

Schmiedt, Hanno, Stephan Schlemmer, Sergey N. Yurchenko, Andrey Yachmenev y Per Jensen. "A semi-classical approach to the calculation of highly excited rotational energies for asymmetric-top molecules". Physical Chemistry Chemical Physics 19, n.º 3 (2017): 1847–56. http://dx.doi.org/10.1039/c6cp05589c.

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3

Carvajal, M., C. Favre, I. Kleiner, C. Ceccarelli, E. A. Bergin y D. Fedele. "Impact of nonconvergence and various approximations of the partition function on the molecular column densities in the interstellar medium". Astronomy & Astrophysics 627 (julio de 2019): A65. http://dx.doi.org/10.1051/0004-6361/201935469.

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We emphasize that the completeness of the partition function, that is, the use of a converged partition function at the typical temperature range of the survey, is very important to decrease the uncertainty on this quantity and thus to derive reliable interstellar molecular densities. In that context, we show how the use of different approximations for the rovibrational partition function together with some interpolation and/or extrapolation procedures may affect the estimate of the interstellar molecular column density. For that purpose, we apply the partition function calculations to astronomical observations performed with the IRAM-30 m telescope towards the NGC 7538–IRS1 source of two N-bearing molecules: isocyanic acid (HNCO, a quasilinear molecule) and methyl cyanide (CH3CN, a symmetric top molecule). The case of methyl formate (HCOOCH3), which is an asymmetric top O-bearing molecule containing an internal rotor is also discussed. Our analysis shows that the use of different partition function approximations leads to relative differences in the resulting column densities in the range 9–43%. Thus, we expect this work to be relevant for surveys of sources with temperatures higher than 300 K and to observations in the infrared.

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4

Che, Dock-Chil, Federico Palazzetti, Yasuhiro Okuno, Vincenzo Aquilanti y Toshio Kasai. "Electrostatic Hexapole State-Selection of the Asymmetric-Top Molecule Propylene Oxide†". Journal of Physical Chemistry A 114, n.º 9 (11 de marzo de 2010): 3280–86. http://dx.doi.org/10.1021/jp909553t.

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5

Vacherand, J. M. y J. Demaison. "Notizen: Remark on the Off-Diagonal Rotational g-Tensor Elements in Asymmetric-Top Molecules". Zeitschrift für Naturforschung A 41, n.º 6 (1 de junio de 1986): 879–80. http://dx.doi.org/10.1515/zna-1986-0616.

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The isotopic dependence of the g-tensor of an asymmetric top molecule is investigated. A relationship is proposed which may be used to determine the g-tensor for isotopic species without measurements.

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6

Oldag, Frank y Dieter H. Sutter. "The Rotational Zeeman Effect in Acetone, its g-Tensor, its Magnetic Susceptibility Anisotropics and its Molecular Electric Quadrupole Moment Tensor; A High Resolution Microwave Fourier Transform Study". Zeitschrift für Naturforschung A 47, n.º 3 (1 de marzo de 1992): 527–32. http://dx.doi.org/10.1515/zna-1992-0315.

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Abstract Acetone is a molecule with an intermediate barrier for methyl- top internal rotation, and only molecules in the A1A1 - state of the tunneling motion exhibit a rigid rotor spectrum. For this state we report the results of a rotational Zeeman effect study of acetone in exterior fields up to 20 kGauss (2 Tesla). From an analysis of the observed Zeeman splittings within the asymmetric top approximation the nonzero elements of the g-tensor and the magnetic susceptibility anisotropies were obtained as follows: gaa= -0.04379 (8), gbb = - 0.06611 (5), gcc=-O.O1481 (7), 2ξaa -ξbb - ξcc = - 9.53 (21) 10-6 erg G -2 mole-1 and 2 ξbb - ξcc - ξaa = 25.57 (18) 10-6 erg G -2 mole-1 . The nonzero elements of the molecular electric quadrupole moment tensor were derived as Qaa- 2-77 (13) DÅ, Qbb= -4.59 (10) DÅ and Qcc= 1.82 (15) DÅ. Zeeman spectra were also recorded for seveal low-J transitions of molecules in the EE-state of methyl top tunneling (one top tunneling), and so far the same splittings have been found as for the A1 A1-species

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7

Song Xiao-Shu, Linghu Rong-Feng, Lü Bing, Cheng Xin-Lu y Yang Xiang-Dong. "Study on high-temperature spectra of the asymptotic asymmetric-top molecule H122C16O". Acta Physica Sinica 57, n.º 6 (2008): 3440. http://dx.doi.org/10.7498/aps.57.3440.

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8

Xiao-Shu, Song, Guo Yun-Dong, Ling-Hu Rong-Feng, Lü Bing, Cheng Xin-Lu y Yang Xiang-Dong. "Study on High-Temperature Spectra of Asymptotic Asymmetric-Top Molecule O 3". Communications in Theoretical Physics 50, n.º 2 (agosto de 2008): 481–85. http://dx.doi.org/10.1088/0253-6102/50/2/40.

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9

Dreizler, H. y S. Kassi. "On the Ambiguity of Complex Structures Derived from one Set of Rotational Constants". Zeitschrift für Naturforschung A 53, n.º 9 (1 de septiembre de 1998): 743–46. http://dx.doi.org/10.1515/zna-1998-0902.

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Abstract It is shown algebraically that from one set of rotational constants or moments of inertia of a complex formed by an asymmetric top molecule and a rare gas atom, eight generally different structures result which are compatible with the moments of inertia.

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10

Mitra, Krishna y Pradip N. Ghosh. "Vibration-internal rotation-rotation Hamiltonian of an asymmetric top molecule with C3v internal rotor". Journal of Molecular Spectroscopy 109, n.º 2 (febrero de 1985): 374–87. http://dx.doi.org/10.1016/0022-2852(85)90320-0.

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11

Rowland, David J. y Julie S. Biteen. "Top-Hat and Asymmetric Gaussian-Based Fitting Functions for Quantifying Directional Single-Molecule Motion". ChemPhysChem 15, n.º 4 (6 de diciembre de 2013): 712–20. http://dx.doi.org/10.1002/cphc.201300774.

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12

Schnyder, T., H. Gross, H. Winkler, H. M. Eppenberger y T. Wallimann. "Structure of the mitochondrial creatine kinase octamer: high-resolution shadowing and image averaging of single molecules and formation of linear filaments under specific staining conditions." Journal of Cell Biology 112, n.º 1 (1 de enero de 1991): 95–101. http://dx.doi.org/10.1083/jcb.112.1.95.

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The combination of high-resolution tantalum/tungsten (Ta/W) shadowing at very low specimen temperature (-250 degrees C) under ultrahigh vacuum (less than 2 x 10(-9) mbar) with circular harmonic image averaging revealed details on the surface structure of mitochondrial creatine kinase (Mi-CK) molecules with a resolution less than 2.5 nm. Mi-CK octamers exhibit a cross-like surface depression dividing the square shaped projection of 10 x 10 nm into four equally sized subdomains, which correspond to the four dimers forming the octameric Mi-CK molecule. By a combination of positive staining (with uranyl acetate) and heavy metal shadowing, internal structures as well as the surface relief of Mi-CK were visualized at the same time at high resolution. Computational image analysis revealed only a single projection class of molecules, but the ability of Mi-CK to form linear filaments, as well as geometrical considerations concerning the formation of octamers by four equal, asymmetric dimers, suggest the existence of at least two distinct faces on the molecule. By image processing of Mi-CK filaments a side view of the octamer differing from the top-bottom projections of single molecules became evident showing a funnel-like access each form the top and bottom of the octamer connected by a central channel. The general structure of the Mi-CK octamer described here is relevant to the localization of the molecule at the inner-outer mitochondrial contact sites and to the function of Mi-CK as an "energy channeling" molecule.

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13

Ortigoso, Juan. "Design of tailored microwave pulses to create rotational coherent states for an asymmetric-top molecule". Physical Review A 57, n.º 6 (1 de junio de 1998): 4592–99. http://dx.doi.org/10.1103/physreva.57.4592.

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14

Che, Dock-Chil, Keita Kanda, Federico Palazzetti, Vincenzo Aquilanti y Toshio Kasai. "Electrostatic hexapole state-selection of the asymmetric-top molecule propylene oxide: Rotational and orientational distributions". Chemical Physics 399 (mayo de 2012): 180–92. http://dx.doi.org/10.1016/j.chemphys.2011.11.020.

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15

Ulenikov, Oleg, Elena Bekhtereva, Olga Gromova, Aleksei Kakaulin, Christian Sydow y Sigurd Bauerecker. "Improved Theory of the Effective Dipole Moments and Absolute Line Strengths of the XY2 Asymmetric Top Molecules in the X2B1 Doublet Electronic States". International Journal of Molecular Sciences 24, n.º 16 (12 de agosto de 2023): 12734. http://dx.doi.org/10.3390/ijms241612734.

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A new effective dipole moment model for the XY2 (C2v−symmetry) molecule in a doublet electronic state is derived that includes (as special cases) all currently known models of effective dipole moments for such types of molecules, and allows us to take into account the influence of spin–rotation interactions on the effective dipole moment operator that were not considered in the preceding studies. Necessary for the analysis of absolute line strengths, the matrix elements of this dipole moment operator are derived. A comparison with the previous analog models is made and discussed. The efficiency of the obtained results is illustrated, which have been applied to a set of the “forbidden” ΔKa=2 transitions of the ν3 band of the OClO free radical molecule.

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16

Perevalov, V. I. y A. A. Lukashevskaya. "Parameterization of the effective dipole moment matrix elements in the case of the asymmetric top molecules. Application to NO2 molecule". Atmospheric and Oceanic Optics 28, n.º 1 (enero de 2015): 17–23. http://dx.doi.org/10.1134/s1024856015010091.

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17

Coudert, L. H. "Optimal control of the orientation and alignment of an asymmetric-top molecule with terahertz and laser pulses". Journal of Chemical Physics 148, n.º 9 (7 de marzo de 2018): 094306. http://dx.doi.org/10.1063/1.5018914.

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18

Hougen, J. T., I. Kleiner y M. Godefroid. "Selection Rules and Intensity Calculations for a Cs Asymmetric Top Molecule Containing a Methyl Group Internal Rotor". Journal of Molecular Spectroscopy 163, n.º 2 (febrero de 1994): 559–86. http://dx.doi.org/10.1006/jmsp.1994.1047.

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19

Oyama, Takahiro, Yuki Ohno, Akemi Tamanai, Yoshimasa Watanabe, Satoshi Yamamoto, Takeshi Sakai, Shaoshan Zeng, Riouhei Nakatani y Nami Sakai. "Laboratory Measurement of CH₂DOH Line Intensities in the Millimeter-wave Region". Astrophysical Journal 957, n.º 1 (19 de octubre de 2023): 4. http://dx.doi.org/10.3847/1538-4357/acf320.

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Abstract Deuterium fractionation in molecules is known as one of the most powerful tools to study chemical processes during star and planet formation. Among various interstellar molecules, methanol often shows very high deuterium fractionation. It is the most abundant saturated organic molecule and is known as a parent species to form more complex organic molecules. However, deriving the abundance of deuterated methanol suffers from the uncertainty in the intrinsic line intensities (S μ 2) of CH3OH isotopologues. Due to their floppy nature, theoretical evaluation of the S μ 2 values is not straightforward, particularly for asymmetric-top asymmetric-frame isotopologues such as CH2DOH. In this study, we have measured the line frequencies and their intensities for CH2DOH in the millimeter-wave region from 216 to 264 GHz by using an emission-type millimeter and submillimeter-wave spectrometer. For the a-type J = 5 − 4 transition, the derived S μ 2 values are 13%–27% larger than those theoretically calculated, except for the transitions of K a = 2 for e 0 and K a = 1 for e 1 affected by avoided level crossing. For b-type transitions, significant systematic differences are found between theoretical and experimental S μ 2 values. The results of the present study enable us to accurately derive from observations the CH2DOH abundances, which are essential for understanding deuterium fractionation in various sources.

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20

Evans, Myron Wyn. "Diffusion of an asymmetric-top molecule in three dimensions. Langevin equations and new, one-particle cross-correlation functions". Journal of the Chemical Society, Faraday Transactions 2 82, n.º 4 (1986): 653. http://dx.doi.org/10.1039/f29868200653.

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21

Maeda, Koki, Sakae Toyoda, Ryosuke Shimojima, Takashi Osada, Dai Hanajima, Riki Morioka y Naohiro Yoshida. "Source of Nitrous Oxide Emissions during the Cow Manure Composting Process as Revealed by Isotopomer Analysis of and amoA Abundance in Betaproteobacterial Ammonia-Oxidizing Bacteria". Applied and Environmental Microbiology 76, n.º 5 (4 de enero de 2010): 1555–62. http://dx.doi.org/10.1128/aem.01394-09.

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ABSTRACT A molecular analysis of betaproteobacterial ammonia oxidizers and a N2O isotopomer analysis were conducted to study the sources of N2O emissions during the cow manure composting process. Much NO2 −-N and NO3 −-N and the Nitrosomonas europaea-like amoA gene were detected at the surface, especially at the top of the composting pile, suggesting that these ammonia-oxidizing bacteria (AOB) significantly contribute to the nitrification which occurs at the surface layer of compost piles. However, the 15N site preference within the asymmetric N2O molecule (SP = δ15Nα − δ15Nβ, where 15Nα and 15Nβ represent the 15N/14N ratios at the center and end sites of the nitrogen atoms, respectively) indicated that the source of N2O emissions just after the compost was turned originated mainly from the denitrification process. Based on these results, the reduction of accumulated NO2 −-N or NO3 −-N after turning was identified as the main source of N2O emissions. The site preference and bulk δ15N results also indicate that the rate of N2O reduction was relatively low, and an increased value for the site preference indicates that the nitrification which occurred mainly in the surface layer of the pile partially contributed to N2O emissions between the turnings.

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22

Uprety, Bhawna y Charmaine Arderne. "The crystal structure of the zwitterionic co-crystal of 2,4-dichloro-6-{[(3-hydroxypropyl)azaniumyl]methyl}phenolate and 2,4-dichlorophenol". Acta Crystallographica Section E Crystallographic Communications 75, n.º 10 (10 de septiembre de 2019): 1452–55. http://dx.doi.org/10.1107/s2056989019012544.

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The title compound, C10H13Cl2NO2·C6H4Cl2O, was formed from the incomplete Mannich condensation reaction of 3-aminopropan-1-ol, formaldehyde and 2,4-dichlorophenol in methanol. This resulted in the formation of a co-crystal of the zwitterionic Mannich base, 2,4-dichloro-6-{[(3-hydroxypropyl)azaniumyl]methyl}phenolate and the unreacted 2,4-dichlorophenol. The compound crystallizes in the monoclinic crystal system (in space group Cc) and the asymmetric unit contains a molecule each of the 2,4-dichlorophenol and 2,4-dichloro-6-{[(3-hydroxypropyl)azaniumyl]methyl}phenolate. Examination of the crystal structure shows that the two components are clearly linked together by hydrogen bonds. The packing patterns are most interesting along the b and the c axes, where the co-crystal in the unit cell packs in a manner that shows alternating aromatic dichlorophenol fragments and polar hydrogen-bonded channels. The 2,4-dichlorophenol rings stack on top of one another, and these are held together by π–π interactions. The crystal studied was refined as an inversion twin.

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23

Fujitake, Masaharu, Jun Nakagawa y Michiro Hayashi. "Microwave spectrum of methyliodosilane: Determination of the dipole moment and eqQ of an asymmetric top molecule containing an atom with a large nuclear quadrupole moment". Journal of Molecular Spectroscopy 119, n.º 2 (octubre de 1986): 367–76. http://dx.doi.org/10.1016/0022-2852(86)90031-7.

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24

PEREDERINA, ANNA, NATALIA NEVSKAYA, OLEG NIKONOV, ALEXEI NIKULIN, PHILIPPE DUMAS, MIN YAO, ISAO TANAKA, MARIA GARBER, GEORGE GONGADZE y STANISLAV NIKONOV. "Detailed analysis of RNA–protein interactions within the bacterial ribosomal protein L5/5S rRNA complex". RNA 8, n.º 12 (diciembre de 2002): 1548–57. http://dx.doi.org/10.1017/s1355838202029953.

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The crystal structure of ribosomal protein L5 from Thermus thermophilus complexed with a 34-nt fragment comprising helix III and loop C of Escherichia coli 5S rRNA has been determined at 2.5 Å resolution. The protein specifically interacts with the bulged nucleotides at the top of loop C of 5S rRNA. The rRNA and protein contact surfaces are strongly stabilized by intramolecular interactions. Charged and polar atoms forming the network of conserved intermolecular hydrogen bonds are located in two narrow planar parallel layers belonging to the protein and rRNA, respectively. The regions, including these atoms conserved in Bacteria and Archaea, can be considered an RNA–protein recognition module. Comparison of the T. thermophilus L5 structure in the RNA-bound form with the isolated Bacillus stearothermophilus L5 structure shows that the RNA-recognition module on the protein surface does not undergo significant changes upon RNA binding. In the crystal of the complex, the protein interacts with another RNA molecule in the asymmetric unit through the β-sheet concave surface. This protein/RNA interface simulates the interaction of L5 with 23S rRNA observed in the Haloarcula marismortui 50S ribosomal subunit.

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25

Margulès, L., B. A. McGuire, R. A. Motiyenko, C. Brogan, T. Hunter, A. Remijan y J. C. Guillemin. "Millimeter wave spectroscopy of cyanoketene (NC–CH=C=O) and an observational search in the ISM". Astronomy & Astrophysics 638 (29 de mayo de 2020): A3. http://dx.doi.org/10.1051/0004-6361/201937183.

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Context. Ketene was detected in the interstellar medium (ISM) in 1977. Until now, only one derivative, the ketenyl radical, has been observed in this medium. Due to its large dipole moment value, cynaoketene is one of the best candidates for possible ketene derivative detection. Aims. To date, the measurements of the rotational spectra have been limited to 60 GHz. The extrapolation of the prediction in the millimeter wave domain is inaccurate and does not permit an unambiguous detection. Methods. The rotational spectra were re-investigated up to 330 GHz. Using the new prediction cyanoketene was sought after in a variety of astronomical sources: NGS 63341, SgrB2(N), and ASAI sources. Results. A total of 1594 transitions were newly assigned and fitted together with those from previous studies, reaching quantum numbers up to J = 82 and Ka = 24. Watson’s asymmetric top Hamiltonian in the Ir representation was used for the analysis; both reductions A and S were tested. Logically, the S reduction gave the best results confirming that the molecule is very close to the prolate limit. Cynaoketene was not found in ISM; upper limits to the column density were derived in each source.

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26

Oeffner, Robert D., Gábor Bunkóczi, Airlie J. McCoy y Randy J. Read. "Improved estimates of coordinate error for molecular replacement". Acta Crystallographica Section D Biological Crystallography 69, n.º 11 (12 de octubre de 2013): 2209–15. http://dx.doi.org/10.1107/s0907444913023512.

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The estimate of the root-mean-square deviation (r.m.s.d.) in coordinates between the model and the target is an essential parameter for calibrating likelihood functions for molecular replacement (MR). Good estimates of the r.m.s.d. lead to good estimates of the variance term in the likelihood functions, which increases signal to noise and hence success rates in the MR search.Phaserhas hitherto used an estimate of the r.m.s.d. that only depends on the sequence identity between the model and target and which was not optimized for the MR likelihood functions. Variance-refinement functionality was added toPhaserto enable determination of the effective r.m.s.d. that optimized the log-likelihood gain (LLG) for a correct MR solution. Variance refinement was subsequently performed on a database of over 21 000 MR problems that sampled a range of sequence identities, protein sizes and protein fold classes. Success was monitored using the translation-functionZ-score (TFZ), where a TFZ of 8 or over for the top peak was found to be a reliable indicator that MR had succeeded for these cases with one molecule in the asymmetric unit. Good estimates of the r.m.s.d. are correlated with the sequence identity and the protein size. A new estimate of the r.m.s.d. that uses these two parameters in a function optimized to fit the mean of the refined variance is implemented inPhaserand improves MR outcomes. Perturbing the initial estimate of the r.m.s.d. from the mean of the distribution in steps of standard deviations of the distribution further increases MR success rates.

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27

Dickinson, A. S., R. Hellmann, E. Bich y E. Vogel. "Transport properties of asymmetric-top molecules". Physical Chemistry Chemical Physics 9, n.º 22 (2007): 2836. http://dx.doi.org/10.1039/b618549e.

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28

Edwards, Beatrice Freya Lucy, Richard John Wheeler, Amy Rachel Barker, Flávia Fernandes Moreira-Leite, Keith Gull y Jack Daniel Sunter. "Direction of flagellum beat propagation is controlled by proximal/distal outer dynein arm asymmetry". Proceedings of the National Academy of Sciences 115, n.º 31 (20 de julio de 2018): E7341—E7350. http://dx.doi.org/10.1073/pnas.1805827115.

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The 9 + 2 axoneme structure of the motile flagellum/cilium is an iconic, apparently symmetrical cellular structure. Recently, asymmetries along the length of motile flagella have been identified in a number of organisms, typically in the inner and outer dynein arms. Flagellum-beat waveforms are adapted for different functions. They may start either near the flagellar tip or near its base and may be symmetrical or asymmetrical. We hypothesized that proximal/distal asymmetry in the molecular composition of the axoneme may control the site of waveform initiation and the direction of waveform propagation. The unicellular eukaryotic pathogens Trypanosoma brucei and Leishmania mexicana often switch between tip-to-base and base-to-tip waveforms, making them ideal for analysis of this phenomenon. We show here that the proximal and distal portions of the flagellum contain distinct outer dynein arm docking-complex heterodimers. This proximal/distal asymmetry is produced and maintained through growth by a concentration gradient of the proximal docking complex, generated by intraflagellar transport. Furthermore, this asymmetry is involved in regulating whether a tip-to-base or base-to-tip beat occurs, which is linked to a calcium-dependent switch. Our data show that the mechanism for generating proximal/distal flagellar asymmetry can control waveform initiation and propagation direction.

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29

Liza, Nishattasnim, Dylan Murphey, Peizhong Cong, David W. Beggs, Yuihui Lu y Enrique P. Blair. "Asymmetric, mixed-valence molecules for spectroscopic readout of quantum-dot cellular automata". Nanotechnology 33, n.º 11 (21 de diciembre de 2021): 115201. http://dx.doi.org/10.1088/1361-6528/ac40c0.

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Abstract Mixed-valence compounds may provide molecular devices for an energy-efficient, low-power, general-purpose computing paradigm known as quantum-dot cellular automata (QCA). Multiple redox centers on mixed-valence molecules provide a system of coupled quantum dots. The configuration of mobile charge on a double-quantum-dot (DQD) molecule encodes a bit of classical information robust at room temperature. When arranged in non-homogeneous patterns (circuits) on a substrate, local Coulomb coupling between molecules enables information processing. While single-electron transistors and single-electron boxes could provide low-temperature solutions for reading the state of a ∼1 nm scale molecule, we propose a room-temperature read-out scheme. Here, DQD molecules are designed with slightly dissimilar quantum dots. Ab initio calculations show that the binary device states of an asymmetric molecule have distinct Raman spectra. Additionally, the dots are similar enough that mobile charge is not trapped on either dot, allowing device switching driven by the charge configuration of a neighbor molecule. A technique such as tip-enhanced Raman spectroscopy could be used to detect the state of a circuit comprised of several QCA molecules.

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30

Patterson, Chris W., R. Scott Smith y Randall B. Shirts. "Rotational adiabatic switching of asymmetric top molecules". Journal of Chemical Physics 85, n.º 12 (15 de diciembre de 1986): 7241–44. http://dx.doi.org/10.1063/1.451361.

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31

Willitsch, S. y F. Merkt. "Rovibronic photoionization dynamics of asymmetric-top molecules". International Journal of Mass Spectrometry 245, n.º 1-3 (agosto de 2005): 14–25. http://dx.doi.org/10.1016/j.ijms.2005.06.004.

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32

Bulthuis, J., J. Möller y H. J. Loesch. "Brute Force Orientation of Asymmetric Top Molecules". Journal of Physical Chemistry A 101, n.º 41 (octubre de 1997): 7684–90. http://dx.doi.org/10.1021/jp9716750.

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33

Wormer, Paul E. S. "Second virial coefficients of asymmetric top molecules". Journal of Chemical Physics 122, n.º 18 (8 de mayo de 2005): 184301. http://dx.doi.org/10.1063/1.1889428.

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34

Flaud, J. M., A. Perrin y C. Camy-Peyret. "Fourier transform spectroscopy of asymmetric top molecules". Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 51, n.º 7 (julio de 1995): 1217–30. http://dx.doi.org/10.1016/0584-8539(94)00148-5.

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35

Chandra, S. y W. H. Kegel. "Collisional rates for asymmetrical top molecules". Astronomy and Astrophysics Supplement Series 142, n.º 1 (febrero de 2000): 113–18. http://dx.doi.org/10.1051/aas:2000142.

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36

Poulsen, Mikael D., Emmanuel Péronne, Henrik Stapelfeldt, Christer Z. Bisgaard, Simon S. Viftrup, Edward Hamilton y Tamar Seideman. "Nonadiabatic alignment of asymmetric top molecules: Rotational revivals". Journal of Chemical Physics 121, n.º 2 (8 de julio de 2004): 783–91. http://dx.doi.org/10.1063/1.1760731.

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37

Zhao, Xiaojun, Ying Yang, David H. A. Fitch y Michael A. Herman. "TLP-1 is an asymmetric cell fate determinant that responds to Wnt signals and controls male tail tip morphogenesis in C. elegans". Development 129, n.º 6 (15 de marzo de 2002): 1497–508. http://dx.doi.org/10.1242/dev.129.6.1497.

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We have isolated mutations defining a new gene, tlp-1, that affect asymmetric cell fates and morphogenesis during the development of the C. elegans tail. tlp-1 mutations cause defects in the specification of asymmetric cell fates in the descendants of the T blast cell, whose polarity is controlled by Wnt signaling and cause abnormal male tail development leading to the formation of a posterior protrusion reminiscent of ‘leptoderan’, or pointy tailed, nematode species. In wild-type C. elegans males, which have a ‘peloderan’ or rounded tail, retraction of the tail tip hypodermis involves a temporally ordered set of cell fusions and changes in cell shape that appear to be heterochronically delayed in tlp-1 males, suggesting that subtle changes in these events can bring about evolutionary changes in morphology. tlp-1 encodes a C2H2 zinc-finger protein that is a member of the Sp family of transcription factors. A TLP-1::GFP fusion protein is expressed in the nuclei of many cells during early embryogenesis and then becomes restricted primarily to posterior cells. At hatching, it is expressed in several head neurons, the posterior intestine cells, tail hypodermal cells, the T cells and specific T-cell descendents in a pattern that suggests TLP-1 may be asymmetrically expressed during the divisions of the T cell lineage. Furthermore, the asymmetry of TLP-1 expression and function appears to be controlled by Wnt signals that control T cell polarity. These results suggest that tlp-1 encodes a transcription factor required for cellular asymmetry that functions downstream of Wnt signals that control cell polarity, as well as in cell fusion and patterning in the C. elegans tail.

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38

Chen, Kuo-Mei. "Laser-Induced Alignments of Symmetric and Asymmetric Top Molecules". Journal of the Chinese Chemical Society 48, n.º 3 (junio de 2001): 609–12. http://dx.doi.org/10.1002/jccs.200100091.

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39

ARANGO, CARLOS A. y GREGORY S. EZRA. "CLASSICAL MECHANICS OF DIPOLAR ASYMMETRIC TOP MOLECULES IN COLLINEAR STATIC ELECTRIC AND NONRESONANT LINEARLY POLARIZED LASER FIELDS: ENERGY-MOMENTUM DIAGRAMS, BIFURCATIONS AND ACCESSIBLE CONFIGURATION SPACE". International Journal of Bifurcation and Chaos 18, n.º 04 (abril de 2008): 1127–49. http://dx.doi.org/10.1142/s0218127408020872.

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We study classical energy-momentum (E-m) diagrams for rotational motion of dipolar asymmetric top molecules in strong external fields. Static electric fields, nonresonant linearly polarized laser fields, and collinear combinations of the two are investigated. We treat specifically the molecules iodobenzene (a nearly prolate asymmetric top), pyridazine (nearly oblate asymmetric top), and iodopentafluorobenzene (intermediate case). The location of relative equilibria in the E-m plane and associated bifurcations are determined by straightforward calculation, with analytical results given where possible. In cases where analytical solutions cannot be obtained, we resort to numerical solutions, while keeping a geometrical picture of the nature of the solutions to the fore. The classification we obtain of the topology of classically allowed rotor configuration space regions in the E-m diagram is of potential use in characterization of energy eigenstates of the corresponding quantum mechanical problem.

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40

Kalmykov, Yu P. "Spectral Moments and Orientation Correlation Functions of Asymmetric Top Molecules". Optics and Spectroscopy 89, n.º 1 (julio de 2000): 23. http://dx.doi.org/10.1134/1.1131509.

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41

Weida, Miles J. y Charles S. Parmenter. "Aligning symmetric and asymmetric top molecules via single photon excitation". Journal of Chemical Physics 107, n.º 18 (8 de noviembre de 1997): 7138–47. http://dx.doi.org/10.1063/1.474955.

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42

Kalmykov, Yu P. y S. V. Titov. "Spectral moments and orientation correlation functions of asymmetric top molecules". Optics and Spectroscopy 89, n.º 1 (julio de 2000): 23–29. http://dx.doi.org/10.1134/bf03355983.

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43

Hain, Toby D., Robert M. Moision y Thomas J. Curtiss. "Hexapole state-selection and orientation of asymmetric top molecules: CH2F2". Journal of Chemical Physics 111, n.º 15 (15 de octubre de 1999): 6797–806. http://dx.doi.org/10.1063/1.480043.

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44

Nakamura, Masaaki, Shiun-Jr Yang, Po-Yu Tsai, Toshio Kasai, King-Chuen Lin, Dock-Chil Che, Andrea Lombardi, Federico Palazzetti y Vincenzo Aquilanti. "Hexapole-Oriented Asymmetric-Top Molecules and Their Stereodirectional Photodissociation Dynamics". Journal of Physical Chemistry A 120, n.º 27 (9 de mayo de 2016): 5389–98. http://dx.doi.org/10.1021/acs.jpca.6b02410.

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45

Watson, James K. G. "Quadratic Herman-Wallis factors for symmetric- and asymmetric-top molecules". Journal of Molecular Spectroscopy 153, n.º 1-2 (mayo de 1992): 211–24. http://dx.doi.org/10.1016/0022-2852(92)90470-9.

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46

Wenger, Ch, W. Raballand, M. Rotger y V. Boudon. "top data system (TDS) software for spectrum simulation of asymmetric molecules". Journal of Quantitative Spectroscopy and Radiative Transfer 95, n.º 4 (noviembre de 2005): 521–38. http://dx.doi.org/10.1016/j.jqsrt.2004.11.012.

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47

Hempel, Andrew, Norman Camerman, Donald Mastropaolo y Arthur Camerman. "Calmodulin antagonists: Structure of N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride (W-7) and comparison with trifluoperazine (TFP) Calmodulin binding". Canadian Journal of Chemistry 83, n.º 8 (1 de agosto de 2005): 1141–45. http://dx.doi.org/10.1139/v05-133.

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The crystal structure of the title compound contains one N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride molecule in the asymmetric unit. The molecule adopts an extended conformation with a linear hexyl group. Protonation occurs at the side chain terminal nitrogen atom. Hydrophobic packing and a three-dimensional hydrogen-bond network, involving all the hydrogen atoms capable of making hydrogen-bond contacts, stabilizes the crystal structure. Due to head-to-head and tail-to-tail arrangement of these hydrophobic molecules, an unusually long cell constant (b = 61.27 Å) characterizes the crystal structure. A stereochemical comparison with trifluoperazine suggests similar calmodulin binding mechanisms.Key words: crystal structure, stereochemistry, W-7, calmodulin binding, TFP.

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48

Dreizler, H., U. Andresen, J. U. Grabow y D. H. Sutter. "On the Measurement of Rotational Spectra of Monodeuterated Asymmetric Top Molecules in Natural Abundance Demonstrated for Monofluorobenzene". Zeitschrift für Naturforschung A 53, n.º 10-11 (1 de noviembre de 1998): 887–90. http://dx.doi.org/10.1515/zna-1998-10-1113.

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Abstract We report on the measurement of rotational transitions of monodeuterated fluorobenzene in natural abundance to show the feasibility of the investigation of monodeuterated asymmetric top molecules without the necessity of isotopic enrichment.

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49

Omiste, J. J., R. González-Férez y P. Schmelcher. "Rotational spectrum of asymmetric top molecules in combined static and laser fields". Journal of Chemical Physics 135, n.º 6 (14 de agosto de 2011): 064310. http://dx.doi.org/10.1063/1.3624774.

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50

Moruzzi, Giovanni. "An automated branch-assignment algorithm for rovibrational spectra of asymmetric-top molecules". Journal of Molecular Spectroscopy 246, n.º 1 (noviembre de 2007): 77–85. http://dx.doi.org/10.1016/j.jms.2007.08.004.

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