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Journal articles on the topic 'Minima of forms'

Author: Grafiati

Published: 17 September 2021

Last updated: 30 July 2025

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1

Brent, Barry. "Quadratic Minima and Modular Forms." Experimental Mathematics 7, no. 3 (1998): 257–74. http://dx.doi.org/10.1080/10586458.1998.10504372.

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2

Brent, Barry. "Quadratic minima and modular forms II." Acta Arithmetica 96, no. 4 (2001): 381–87. http://dx.doi.org/10.4064/aa96-4-8.

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3

VULAKH, L. YA. "MINIMA OF BINARY INDEFINITE HERMITIAN FORMS." International Journal of Number Theory 06, no. 02 (2010): 411–35. http://dx.doi.org/10.1142/s1793042110003034.

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Classification of binary indefinite primitive Hermitian forms modulo the action of the extended Bianchi group (or Hilbert modular group) Bd is given. When the discriminant of the quadratic field [Formula: see text] (and d) is negative, the results obtained can be applied to classify the maximal non-elementary Fuchsian subgroups of Bd, and to find the Hermitian points in the Markov spectrum of Bd. If ν is a Hermitian point in the spectrum, then there is a set of extremal geodesics in H3, the upper half-space model of the three-dimensional hyperbolic space, with diameter 1/ν, which depends on on

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4

Krieg, Aloys. "Primitive minima of positive definite quadratic forms." Acta Arithmetica 63, no. 1 (1993): 91–96. http://dx.doi.org/10.4064/aa-63-1-91-96.

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5

Vulakh, L. Ya. "On minima of rational indefinite quadratic forms." Journal of Number Theory 21, no. 3 (1985): 275–85. http://dx.doi.org/10.1016/0022-314x(85)90056-3.

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6

Grover, V. K., and M. Raka. "On inhomogeneous minima of indefinite binary quadratic forms." Acta Mathematica 167 (1991): 287–98. http://dx.doi.org/10.1007/bf02392452.

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7

Seeger, Alberto, and Mounir Torki. "Local minima of quadratic forms on convex cones." Journal of Global Optimization 44, no. 1 (2007): 1–28. http://dx.doi.org/10.1007/s10898-007-9225-2.

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8

Raka, Madhu. "Inhomogeneous minima of a class of ternary quadratic forms." Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics 55, no. 3 (1993): 334–54. http://dx.doi.org/10.1017/s144678870003408x.

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AbstractLet denote the kth successive inhomogeneous minima for positive values of real indefinite ternary quadratic forms of type (2, 1). Here it is proved that for the class of zero forms, All the critical forms have also been obtained. is already known. For non-zero forms it is proved that .

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9

Jaeggi, Rahel. ""No Individual Can Resist": Minima Moralia as Critique of Forms of Life." Constellations 12, no. 1 (2005): 65–82. http://dx.doi.org/10.1111/j.1351-0487.2005.00403.x.

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10

Iannacci, Paola. "L’ENUNCIATO: UNITÀ COMUNICATIVA MINIMA IN PROSPETTIVA DIDATTICA." Italiano LinguaDue 14, no. 1 (2022): 681–97. http://dx.doi.org/10.54103/2037-3597/18321.

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Si può cominciare già dalla scuola secondaria di primo grado a far vedere l’intreccio di livelli e piani e a mettere a fuoco le relazioni e le gerarchie che costituiscono l’architettura semantica di un testo? La dimensione testuale va riconosciuta soprattutto dal docente che si deve dotare degli strumenti messi a disposizione dalla linguistica del testo e dagli studi più recenti, ma nella didattica se ne deve tener conto già nei livelli più bassi. I contenuti dell’articolo suggeriscono un approccio a tale dimensione a partire dal riconoscimento e dall’analisi dell’Enunciato, unità comunicativa

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11

Abe, Ryuji, and Iain R. Aitchison. "Symmetry of topographs of Markoff forms." International Journal of Number Theory 16, no. 07 (2020): 1573–98. http://dx.doi.org/10.1142/s1793042120500839.

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The Markoff spectrum is defined as the set of normalized values of arithmetic minima of indefinite quadratic forms. In the theory of the Markoff spectrum we observe various kinds of symmetry. Each of Conway’s topographs of quadratic forms which give values in the discrete part of the Markoff spectrum has a special infinite path consisting of edges. It has symmetry with respect to a translation along the path and countable central symmetries by which the path is invariant. We prove that these properties are obtained from the fact that the path is a discretization of a geodesic in the upper half

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12

Skubenko, B. F. "Minima of decomposable forms of degree n in n variables for n ? 3." Journal of Soviet Mathematics 62, no. 4 (1992): 2928–35. http://dx.doi.org/10.1007/bf01098925.

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13

Patra, Shanti G., Nirmal K. Shee, Michael G. B. Drew, and Dipankar Datta. "Angle isomerism, as exemplified in a five-coordinate, dimeric copper(ii) Schiff base complex. Observation of Ostwald ripening." New Journal of Chemistry 40, no. 4 (2016): 3238–43. http://dx.doi.org/10.1039/c5nj02765a.

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14

Chattopadhyay, Anjan, Praveen Saini, and Riddhish Pandharkar. "Exploring the isomerization paths of push–pull hexatrienes." RSC Advances 6, no. 91 (2016): 88433–42. http://dx.doi.org/10.1039/c6ra16812d.

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The first photo-excited singlet state of all-trans donor (amine), acceptor (cyano)-substituted hexatriene forms donor side-twisted minima and its passage towards the cis–trans–trans isomer is characterized by an S<sub>0</sub>/S<sub>1</sub> conical intersection.

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15

Liu, Wei-Chun, and François P. Gabbaï. "Characterization of a Lewis adduct in its inner and outer forms." Science 385, no. 6714 (2024): 1184–88. http://dx.doi.org/10.1126/science.adp7465.

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The entrance channel of bimolecular reactions sometimes involves the formation of outer complexes as weakly bound, fleeting intermediates. Here, we characterize such an outer complex in a system that models the bimolecular, C-O bond–forming reaction of a phosphine oxide Lewis base with a carbenium Lewis acid. Crystallographic studies show that the C-O distance in the outer form exceeds that of the final or inner adduct by 1.1 angstroms. As the system samples the two forms of the complex, which correspond to minima on the corresponding potential energy surface, the C-O linkage switches from a s

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16

Drátovský, Milan, Ludmila Langová, Jiří Makovička, and Jaroslav Rosický. "The Na+,K+/CN-,I- ternary reciprocal system." Collection of Czechoslovak Chemical Communications 56, no. 10 (1991): 2148–53. http://dx.doi.org/10.1135/cccc19912148.

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The DTA method was used to obtain the phase diagram of the Na+, K+/CN-, I- ternary reciprocal system. This system forms completely miscible solid solutions with two ternary minima with the parameters xNa+ = 0.50, xI- = 0.57, θ = 412°C, and xNa+ = 0.75, xI- = 0.20, θ = 428°C. The NaI-KCN diagonal is the stable diagonal.

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17

Ramek, Michael, Ching-Hsing Yu, and Lothar Schäfer. "Article." Canadian Journal of Chemistry 76, no. 5 (1998): 566–75. http://dx.doi.org/10.1139/v98-063.

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The ab initio conformational energy minima of the model tripeptide N-formyl-L-alanyl-L-alanine amide (ALA-ALA) were determined by ab initio RHF/4-21G and RHF/6-31G* gradient geometry refinement. For the current investigation, 11 664 RHF/4-21G structures were optimized, representing grid points in the four-dimensional (phi1, psi1, phi2, psi2) conformational space, which were constructed in 40° increments along the outer torsions phi1 and psi2 and in 30° increments along the inner torsions psi1 and phi2 of ALA-ALA. Two new energy minima, previously not reported, are described. The positions of t

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18

Sekuler, Allison B. "Local and Global Minima in Visual Completion: Effects of Symmetry and Orientation." Perception 23, no. 5 (1994): 529–45. http://dx.doi.org/10.1068/p230529.

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The visual information that specifies three-dimensional objects is often incomplete because objects occlude parts of themselves and other objects. Yet people rarely have difficulty perceiving complete, three-dimensional forms. Somehow the visual system seems to ‘complete’ partially specified objects. The perceptual processes underlying this seemingly effortless and immediate completion are poorly understood. Sekuler and Palmer designed in 1992 the primed-matching paradigm for the objective study of completion effects and their microgenesis. Results from the paradigm suggest that global process

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19

Alvarado, Raúl, Gustavo Cárdenas, Juan J. Nogueira, Nicolás Ramos-Berdullas, and Marcos Mandado. "On the Permeation of Polychlorinated Dibenzodioxins and Dibenzofurans through Lipid Membranes: Classical MD and Hybrid QM/MM-EDA Analysis." Membranes 13, no. 1 (2022): 28. http://dx.doi.org/10.3390/membranes13010028.

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The permeation of dioxin-like pollutants, namely, chlorinated dibenzodioxins and dibenzofurans, through lipid membranes has been simulated using classic molecular dynamics (CMD) combined with the umbrella sampling approach. The most toxic forms of chlorinated dibenzodioxin and dibenzofuran, 2,3,7,8-tetrachloro-p-dibenzodioxin (TCDD) and 2,3,7,8-tetrachlorodibenzofuran (TCDF), and a dioleyl-phosphatidylcholine (DOPC) lipid membrane of 50 Å wide have been chosen for our study. The free energy profile shows the penetration process is largely favoured thermodynamically (ΔG ≈ −12 kcal/mol), with a

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20

Anandakumar, K., Nageswararao Pacha, J. Saminathan, R. Subathrai, and Kumarasamy Gandla. "Development of Difference Spectroscopic Method for the Estimation of Balsalazide in Bulk and in Formulation." E-Journal of Chemistry 6, no. 3 (2009): 809–13. http://dx.doi.org/10.1155/2009/360972.

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A simple, precise and accurate difference spectroscopic method has been developed for the estimation of balsalazide in bulk and in pharmaceutical dosage form. The proposed method is based on the principle that balsalazide can exhibit two different chemical forms in basic and acidic medium that differ in the absorption spectra in basic and acidic medium. Since the drug was freely soluble in distilled water, a stock solution (1 mg/mL) was prepared with distilled water. Further dilution was made by using 0.1 M sodium hydroxide and 0.1 M hydrochloric acid separately. The maxima and minima in the d

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21

Pereira, Ricardo, Monique Feist, and Ana C. Azerêdo. "New charophytes from the Upper Jurassic of the Lusitanian Basin (Portugal)." Journal of Micropalaeontology 22, no. 2 (2003): 113–26. http://dx.doi.org/10.1144/jm.22.2.113.

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Abstract. In the Lusitanian Basin (west-central Portugal), Upper Jurassic (Oxfordian) sediments were investigated in order to identify palaeontological assemblages of charophytes. Systematic studies were undertaken on specimens obtained from four field sections (Pedrógão, Vale de Ventos, Memória and Valverde). These studies revealed the presence of new forms of Porocharaceae (Porochara pedunculata n. sp) and of forms previously unknown in this region (Auerbachichara cf. saidakovskyi), as well as P. raskyae, P. minima, P. fusca, P. sulcata, P. kimmeridgensis, Aclistochara longiformis and Poroch

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22

Younesie, Mostafa. "Minima Onomastica Graeca Alpharabia: Notes on the Treatise "tafsir asma al-hukama"." Collectanea Philologica, no. 24 (December 28, 2021): 127–40. http://dx.doi.org/10.18778/1733-0319.24.08.

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One of the treatises attributed to the scholar and philosopher al-Farabi is the fascinating single- page manuscript entitled tafsir asma al-hukama, a small document containing a shorthand inventory of fourteen Greek names. Although the authenticity of the attribution is still debated, the treatise itself demonstrates that its author had a strong interest in the interplay of philology and philosophy – a theme that first appears in a remarkable passage in Plato’s Politeia, namely Book IX, 582e. This paper therefore will examine the nature of the tafsir asma al-hukama, especially with regard to t

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23

Dułak, Dawid, Małgorzata Gadzała, Mateusz Banach, et al. "Filamentous Aggregates of Tau Proteins Fulfil Standard Amyloid Criteria Provided by the Fuzzy Oil Drop (FOD) Model." International Journal of Molecular Sciences 19, no. 10 (2018): 2910. http://dx.doi.org/10.3390/ijms19102910.

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Abnormal filamentous aggregates that are formed by tangled tau protein turn out to be classic amyloid fibrils, meeting all the criteria defined under the fuzzy oil drop model in the context of amyloid characterization. The model recognizes amyloids as linear structures where local hydrophobicity minima and maxima propagate in an alternating manner along the fibril’s long axis. This distribution of hydrophobicity differs greatly from the classic monocentric hydrophobic core observed in globular proteins. Rather than becoming a globule, the amyloid instead forms a ribbonlike (or cylindrical) str

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24

Starkey, J. M., and J. E. Bernard. "A Constraint Function Technique for Improved Structural Dynamics." Journal of Vibration and Acoustics 108, no. 1 (1986): 101–6. http://dx.doi.org/10.1115/1.3269292.

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A constraint function approach is presented for finding design changes that remove natural frequencies from undesirable frequency bands for lightly damped structures. The technique requires the minimization of a function which becomes smaller when (1) natural frequencies clear out of undesirable bands, and (2) design changes become small. Useful forms of these functions are defined, and the number of possible minima is explored. Graphical intepretations of the constraint functions are given, and an example is included which shows the effects of the parameters which weight these two functions.

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25

R., Tijar, El Merbouh B., Bourjila M., et al. "Conformational space analysis of neutral and deprotonated forms of benzoic acid, salicylic acid and phthalic acid using a genetic algorithm." Chemistry International 2, no. 4 (2016): 201–21. https://doi.org/10.5281/zenodo.1471383.

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In this paper we present a detailed conformational study of three aromatic systems constituting the basic units of humic acids namely benzoic acid, salicylic acid and phthalic acid. The genetic algorithm, based on the multi-niche crowding (MNC) method, coupled with the semi-empirical AM1 method is used to analyze the potential energy surface (PES) of these systems. This algorithm, implemented in the MOPAC program and piloted by scripts, provides better detection of global and local minima in a reasonable time. The results obtained are comparable with those of previous studies. Three factors ca

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26

Sayyed-Alangi, S. Zahra, and Mohammad T. Baei. "Ab Initioand DFT Studies of Conformational Properties of Heteroatom Containing Ketene Analogues and Their Comparison with the Related Cyclic Analogues." E-Journal of Chemistry 9, no. 1 (2012): 193–202. http://dx.doi.org/10.1155/2012/380109.

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Minimum-energy and transition state geometries of 3-thioxoprop-2-enethial, 3-thioxoacrylaldehyde, 3-oxoprop-2-enethial, 3-selenoxoprop-2-enethial, 3-thioxoprop-2-eneselenal, 3-selenoxoprop-2-eneselenal, 3-oxoacrylaldehyde, 3-selenoxoacrylaldehyde and 3-oxoprop-2-eneselenal were calculated using HF, B3LYP and MP2 levels of theory and 6-31+G*basis set by rotation around the related -C-C- single bonds. In all of the above mentioned molecules, the s-trans conformation was obtained as the most stable conformer with the 180°dihedral angle, apart from 3-oxoprop-2-enethial and 3-thioxoprop-2-eneselena

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27

Sokolov, S. Yu, and A. S. Bich. "COMPARISON OF THE SPATIAL LOCATION OF DEEP-SEA POLYMETALLIC SULPHIDE ORE OBJECTS AND DEEP MANTLE STRUCTURE BASED ON GEOPHYSICAL FIELDS IN THE NORTHERN NEAR-EQUATORIAL SEGMENT OF THE MID-ATLANTIC RIDGE." Bulletin of Kamchatka Regional Association «Educational-Scientific Center». Earth Sciences 2(62) (June 28, 2024): 35–48. http://dx.doi.org/10.31431/1816-5524-2024-2-62-35-48.

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A comparison of geophysical data along the segment of the Mid-Atlantic Ridge (MAR) between 10° N and 25° N and seafloor massive sulfides (SMS) ore objects revealed a number of regularities and relationships in their spatial distribution. SMS are grouped in areas with the following features: near subvertical «microplumes», into which the single axial anomaly of the MAR, determined by the seismotomographic model UU-P07, splits; maximums of Bouguer anomalies between the Vema and Kane transform faults, corresponding to dense mantle volumes and minimal magmatic debit; a pronounced alternation of sp

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28

Lakshmana, Prabu, Suriya Prakash, and A. Shanmugarathinam. "Development of difference spectrophotometric method for the estimation of leflunomide in tablet dosage form." Chemical Industry and Chemical Engineering Quarterly 18, no. 3 (2012): 407–10. http://dx.doi.org/10.2298/ciceq110804016l.

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A new simple, accurate, precise, highly sensitive and reproducible difference spectrophotometric method for the determination of leflunomide in bulk and pharmaceutical dosage form is described. Difference spectroscopic method is based on the principle that leflunomide exhibit two different forms; in acidic and basic medium which differs in their absorption spectra. The difference spectra were obtained by reading the absorbance of leflunomide in 0.1N HCl in the reference cell and the absorbance of leflunomide in 0.1N NaOH in the sample cell and vice versa; in the difference spectrum maxima and

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29

Maithy, P. K., and Rupendra Babu. "The Mid-Proterozoic Vindhyan Macrobiota from Chopan, Southeast Uttar Pradesh." Journal Geological Society of India 31, no. 6 (1988): 584–90. http://dx.doi.org/10.17491/jgsi/1988/310606.

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Abstract Macrobiota comprising body fossils and trace fossils are reported from the Semri and Kaimur Groups of the Vindhyan Supergroup exposed around Chopan. Carbonaceous compressions of Chuaria minima and Tawuia dalensis, impressions of Sekwia excentrica and moulds of Longfengsahnia chopanensis sp. nov. are reported from the Rohtas Limestone Formation, Semri Group. Beside these, Longfengsahnia stiplala and epirelief of trace fossils belonging to possibly annelids are reported from the Ghurma Shale Formation of Kaimur Group. The macrobiota record indicates that during the Rohtas time free plan

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30

Nguyen‐Tuan, Long, Feras Alkam, and Tom Lahmer. "Damage identification based on XFEM: inverse analysis and experimental validation." ce/papers 6, no. 6 (2023): 1470–75. http://dx.doi.org/10.1002/cepa.2897.

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AbstractModel‐based inverse analyses emerge as an alternative means to reconstruct buried objects in structures. In this paper, we introduced an inverse analysis using XFEM and adjoint method to identify the cracks, which is based on laboratory experimental data. XFEM model allows precisely reproducing the crack forms in the structures, whilst adjoint state with level set for inverse problem allows calculating the gradient of complex geometrical structures and avoiding the local minima traps. Besides proposing a modification XFEM to model reinforced concrete behaviors, we also establish the ad

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31

Durig, J. R., T. G. Costner, and T. S. Little. "Raman and infrared spectra, conformational stability, vibrational assignment, and ab initio calculations of cis-1,3-dichloropropene." Canadian Journal of Chemistry 71, no. 10 (1993): 1751–63. http://dx.doi.org/10.1139/v93-218.

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The Raman (3200−10 cm−1) and infrared (3200−20 cm−1) spectra of gaseous and solid cis-1,3-dichloropropene, cis-ClHC=CHCH2Cl, have been recorded. Additionally, the Raman spectrum of the liquid with qualitative depolarization data has also been obtained. These spectral data have been interpreted on the basis that the molecule exists predominantly in the gauche (allylic chlorine atom oriented gauche to the double bond) conformation in all physical phases. Some bands in the infrared spectrum of the gas could be due to a second higher energy conformer but the lack of corresponding Raman bands casts

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32

Spaltro, Agustín, Melina G. Peluas, Carlos O. Della Védova, and Rosana M. Romano. "Conformational Analysis of Trifluoroacetyl Triflate, CF3C(O)OSO2CF3: Experimental Vibrational and DFT Investigation." Spectroscopy Journal 2, no. 2 (2024): 68–81. http://dx.doi.org/10.3390/spectroscj2020005.

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The conformations of trifluoroacetyl triflate, CF3C(O)OSO2CF3, were investigated through experimental vibrational methods (gas-phase FTIR, liquid-phase Raman, and Ar matrix FTIR spectroscopy) and density functional theory (DFT) calculations. A potential energy surface was computed using the B3P86/6-31+g(d) approximation as a function of the dihedral angles τ1 = CC−OS and τ2 = CO−SC. The surface reveals three minima, which were further optimized using the B3LYP method with various basis sets (6-31++G(d), 6-311++G(d), tzvp, and cc-pvtz). The global minimum corresponds to a syn–anti conformer (th

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33

MA, N. L., and P. WU. "A DENSITY FUNCTIONAL STUDY OF THE STRUCTURE OF SILANE COUPLING AGENT 3–AMINOPROPYLTRIETHOXYSILANE." Journal of Theoretical and Computational Chemistry 04, no. 01 (2005): 117–26. http://dx.doi.org/10.1142/s021963360500157x.

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Using density functional theory, we predicted the solution structure of the hydrolyzed 3–aminopropyltriethoxysilane (h–APS), which is a silane coupling agent commonly used in many industrial applications. We have located five stable minima on the potential energy surface of h–APS in which four of them are "neutral", and the remaining one is zwitterionic (dipolar) in nature. Our calculations suggested that the stability of the most stable form of h–APS in water (denoted as II_N) arose from strong intramolecular OH ⋯ N hydrogen bond. The least stable form is the zwitterionic form (I_ZW), which i

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34

Sabirov, Abudvakhid. "Definition of Foraminiferal Zones in the Famennian Stage (upper Devonian) of Tajikistan." Journal of Foraminiferal Research 49, no. 2 (2019): 163–77. http://dx.doi.org/10.2113/gsjfr.49.2.163.

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AbstractSeven foraminiferal zones [Parathurammina dagmarae–Saltovskajina scitula–Neoarchaesphaera, Septaglomospiranella primaeva, Quasiendothyra (Eoquasiendothyra) bella, Q. (Eoendothyra) communis, Q. (E.) regularis, Q. (Q.) kobeitusana–Endoglomospiranella imminuta, and Q. (Q.) konensis–End. Nigra] have been identified from Famennian Stage carbonate sections in Tajikistan and compared to foraminiferal sequences from the Franco-Belgian Basin, the Russian part of the Eastern European Platform, the Ural Mountains (Russia), and Kyrgyzstan. The lower Famennian boundary is marked by the rapid extinc

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Gavezzotti, A. "Polymorphism of 7-dimethylaminocyclopenta[c]coumarin: packing analysis and generation of trial crystal structures." Acta Crystallographica Section B Structural Science 52, no. 1 (1996): 201–8. http://dx.doi.org/10.1107/s0108768195008895.

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The crystal structures of two polymorphs of the title compound [Pbca and Pna21; Jasinski & Woudenberg (1995). Acta Cryst. C51, 107–109] were analysed. Packing energies and indices were compared. Molecules in the two forms show a slight conformational difference; both conformers were packed in some of the most frequent space groups for organic molecules (P21, P21/c, P212121 and Pna21) using a computer program for crystal structure generation and prediction (PROMET3). The results of such calculations are used to provide tentative explanations for the preference of the two conformers for cent

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ΜΑΡΚΟΠΟΥΛΟΥ- ΔΙΑΚΑΝΤΩΝΗ, Α., Ρ. Μ. ΜΙΡΚΟΥ, and Μ. ΠΑΠΑΔΑΚΗ. "The finding of bryozoans from the lower Pliocence of Crete (Maronia - Sitia). Systematics - Paleoecology." Bulletin of the Geological Society of Greece 34, no. 2 (2018): 503. http://dx.doi.org/10.12681/bgsg.16982.

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A rich fauna of Bryozoa from the Lower Pliocene of the Maronia district (location of Hagios loannis) had been studied. 47 species have been indentified belonging to the Cyclostomata (16) and Cheilostomata (31). This study allows to precise - based on the Foraminifers - the distribution of Bryozoans in this area of the South- East Mediterranean. Based on the zoarial forms, the bathymetry, the temperature and the bottoms, where some species live yet now, we attempt to give a reconstruction of the paleoenvironments. The Lower Pliocene age is based on the stratigraphie distribution of the followin

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37

Suryanarayanan, T. S., V. Kumaresan, and J. A. Johnson. "Foliar fungal endophytes from two species of the mangrove Rhizophora." Canadian Journal of Microbiology 44, no. 10 (1998): 1003–6. http://dx.doi.org/10.1139/w98-087.

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Endophytic fungi were isolated from leaves of Rhizophora apiculata Bl. and Rhizophora mucronata Lamk., two typical mangrove plants growing in the Pichavaram mangrove of Tamil Nadu, Southern India. Three hundred leaf segments from each plant species were sampled during dry and rainy months. More endophytes could be isolated during the rainy months than during the dry period. Hyphomycetes and sterile forms were more prevalent than ascomycetes or coelomycetes. Sporormiella minima, Acremonium sp. strain MG1 and a sterile fungus (MG90) were isolated from both plants irrespective of the season. Some

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Bartol, Ian K., Roger Mann, and Mark R. Patterson. "Aerobic respiratory costs of swimming in the negatively buoyant brief squidLolliguncula brevis." Journal of Experimental Biology 204, no. 21 (2001): 3639–53. http://dx.doi.org/10.1242/jeb.204.21.3639.

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SUMMARYBecause of the inherent inefficiency of jet propulsion, squid are considered to be at a competitive disadvantage compared with fishes, which generally depend on forms of undulatory/oscillatory locomotion. Some squid, such as the brief squid Lolliguncula brevis, swim at low speeds in shallow-water complex environments, relying heavily on fin activity. Consequently, their swimming costs may be lower than those of the faster, more pelagic squid studied previously and competitive with those of ecologically relevant fishes. To examine aerobic respiratory swimming costs, O2 consumption rates

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Goyal, Parnika, Dimpy Rani, and Renu Chadha. "EXPLORING STRUCTURAL ASPECTS OF NATEGLINIDE POLYMORPHS USING POWDER X-RAY DIFFRACTION." International Journal of Pharmacy and Pharmaceutical Sciences 9, no. 10 (2017): 119. http://dx.doi.org/10.22159/ijpps.2017v9i10.20795.

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Objective: The present manuscript highlights the structural aspects of some polymorphic forms of nateglinide using powder x-ray diffraction (PXRD) pattern.Methods: All the polymorphic forms were isolated as microcrystalline powder, therefore, powder diffraction patterns was used as a tool to determine the crystal structure. For this, Reflux Plus module of BIOVIA Material Studio software was used. Polymorph prediction (PP) and crystal morphology analysis were performed to estimate the global minimum in lattice energy landscape and morphologically important (M. I.) facets, respectively. Besides

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Rigby, J. Keith, and A. W. Potter. "Ordovician Sphinctozoan Sponges from the Eastern Klamath Mountains, Northern California." Journal of Paleontology 60, S20 (1986): 1–47. http://dx.doi.org/10.1017/s0022336000060820.

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Extensive silicified faunules of Middle and Late Ordovician sphinctozoan sponges have been assembled from the northern part of the eastern Klamath Mountains in northern California. The sponges are from eugeosynclinal rocks that are the westernmost Middle Ordovician to Late Devonian rocks at that latitude in North America. Seventeen new species occur in the assemblages, including 10 porate and 7 aporate forms. New genera of porate forms areAmblysiphonelloidesandCorymbospongia, and new porate species include:Amblysiphonella grossa, Amblysiphonelloides tubula, A. reticulata, Imperatoria mega, I.

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Milenin, Andrey I., Anna A. Popova, and Konstantin A. Shestibratov. "Effect of Type of Forest Growth Conditions and Climate Elements on the Dynamics of Radial Growth in English Oak (Quercus robur L.) of Early and Late Phenological Forms." Forests 14, no. 1 (2022): 11. http://dx.doi.org/10.3390/f14010011.

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The pattern of annual radial growth is influenced by various factors: the local growth conditions, the age structure, and the ecotypes or provenances of trees. A more in-depth approach to the study of specific growth patterns of tree forms is needed to predict the further genesis of forests. This research was carried out on healthy English oak trees of early (EF) and late (LF) phenological forms in Shipov Forest, Voronezh Region. The dendroclimatic analysis was performed on permanent sample plots in wet, dry, and very dry oak stands grown on different soil types. The effect of precipitation on

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Ozbay, Serkan. "Modified Backpropagation Algorithm with Multiplicative Calculus in Neural Networks." Elektronika ir Elektrotechnika 29, no. 3 (2023): 55–61. http://dx.doi.org/10.5755/j02.eie.34105.

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Backpropagation is one of the most widely used algorithms for training feedforward deep neural networks. The algorithm requires a differentiable activation function and it performs computations of the gradient proceeding backwards through the feedforward deep neural network from the last layer through to the first layer. In order to calculate the gradient at a specific layer, the gradients of all layers are combined via the chain rule of calculus. One of the biggest disadvantages of the backpropagation is that it requires a large amount of training time. To overcome this issue, this paper prop

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GARCKE, HARALD, BRITTA NESTLER, BJÖRN STINNER, and FRANK WENDLER. "ALLEN–CAHN SYSTEMS WITH VOLUME CONSTRAINTS." Mathematical Models and Methods in Applied Sciences 18, no. 08 (2008): 1347–81. http://dx.doi.org/10.1142/s0218202508003066.

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We consider the evolution of a multi-phase system where the motion of the interfaces is driven by anisotropic curvature and some of the phases are subject to volume constraints. The dynamics of the phase boundaries is modeled by a system of Allen–Cahn type equations for phase field variables resulting from a gradient flow of an appropriate Ginzburg–Landau type energy. Several ideas are presented in order to guarantee the additional volume constraints. Numerical algorithms based on explicit finite difference methods are developed, and simulations are performed in order to study local minima of

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Näther, C., N. Nagel, H. Bock, W. Seitz, and Z. Havlas. "Structural, kinetic and thermodynamic aspects of the conformational dimorphism of diethyl 3,6-dibromo-2,5-dihydroxyterephthalate." Acta Crystallographica Section B Structural Science 52, no. 4 (1996): 697–706. http://dx.doi.org/10.1107/s0108768196003187.

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The crystal structures of the title compound and of its ethanol solvate have been determined by X-ray diffraction. The compound crystallizes in two different crystal forms (I: P21/n, high-temperature stable modification, II: P21/c, room-temperature stable modification), which differ in molecular conformation and hydrogen bonding. Ab initio calculations show that both observed conformations correspond to local energy minima and predict the conformation in polymorph (II) to be energetically more favourable. Packing energy calculations confirm that form (II) should be more stable than form (I). C

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M., Bourjila, El Merbouh B., Tijar R., et al. "Polyalanine gas phase acidities determination and conformational space analysis by genetic algorithm assessment." Chemistry International 2, no. 3 (2016): 145–57. https://doi.org/10.5281/zenodo.1470690.

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The genetic algorithm, based on the Multi-Niche Crowding (MNC) method, coupled with the semi-empirical AM1 method is used to analyze the potential energy surface of some polypeptides containing cysteine. Calculating the formation energies of these systems in both neutral and deprotonated states, we deducted their enthalpy of deprotonation (ΔHacid) and we identified the types of rearrangement of these systems when isolated. Deprotonation occurs at the level of the alone acid site characterizing these peptides namely the thiol. The values obtained for the deprotonation enthalpies of polype

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Usoskin, I. G., S. K. Solanki, N. A. Krivova, et al. "Solar cyclic activity over the last millennium reconstructed from annual 14C data." Astronomy & Astrophysics 649 (May 2021): A141. http://dx.doi.org/10.1051/0004-6361/202140711.

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Aims. The 11-year solar cycle (Schwabe cycle) is the dominant pattern of solar magnetic activity reflecting the oscillatory dynamo mechanism in the Sun’s convection zone. Solar cycles have been directly observed since 1700, while indirect proxy data suggest their existence over a much longer period of time, but generally without resolving individual cycles and their continuity. Here we reconstruct individual solar cycles for the last millennium using recently obtained 14C data and state-of-the-art models. Methods. Starting with the 14C production rate determined from the so far most precise me

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Espinosa-Garcia, J., M. Monge-Palacios, and J. C. Corchado. "Constructing Potential Energy Surfaces for Polyatomic Systems: Recent Progress and New Problems." Advances in Physical Chemistry 2012 (October 9, 2012): 1–19. http://dx.doi.org/10.1155/2012/164752.

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Different methods of constructing potential energy surfaces in polyatomic systems are reviewed, with the emphasis put on fitting, interpolation, and analytical (defined by functional forms) approaches, based on quantum chemistry electronic structure calculations. The different approaches are reviewed first, followed by a comparison using the benchmark H + CH4 and the H + NH3 gas-phase hydrogen abstraction reactions. Different kinetics and dynamics properties are analyzed for these reactions and compared with the available experimental data, which permits one to estimate the advantages and disa

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Bujaroska, Biljana, Kiro Stojanoski, and Ljupco Pejov. "On the differential hydration of various forms of glycine in diluted aqueous solutions: a Monte Carlo study." Macedonian Journal of Chemistry and Chemical Engineering 31, no. 2 (2012): 295. http://dx.doi.org/10.20450/mjcce.2012.11.

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Rigid-body Monte Carlo simulations were carried out to study the differential hydration of zwitterionic and neutral forms of glycine in water. To account for the solute polarization by the rather polar liquid environment, initial geometries were chosen as minima on the MP2/aug-cc-pVTZ potential energy surfaces of neutral and zwitterionic glycine continuously solvated by water, implementing the polarizable continuum model (PCM) within the integral equation formalism (IEFPCM). The dynamically changing hydrogen bonding network between the solute and solvent molecules was analyzed imposing distanc

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Neumann, Klaus, W. Berry Lyons, and David J. Des Marais. "Inorganic carbon-isotope distribution and budget in the Lake Hoare and Lake Fryxell basins, Taylor Valley, Antarctica." Annals of Glaciology 27 (1998): 685–89. http://dx.doi.org/10.3189/1998aog27-1-685-689.

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One of the unusual features of Lakes Fryxell and Hnare in Taylor Valley, southern Victoria Land, Antarctica, is their perennial ice cover. This ice cover limits gas exchange between the atmosphere and the lake water, and causesa very stable stratification of the lakes. We analyzed a series of water samples from profiles of these lakes and their tributaries for δ13C of the dissolved inorganic carbon (DIC) in order to qualify the carbon flux from the streams into the lakes, and to investigate the carbon cycling with in the lakes. Isotopic values in the uppermost waters (δ13C = +l.3‰ to 5.3‰ in L

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SAINI, AJAY, SREENIVASULU K. REDDY, and NARENDRA JAWALI. "Intra-individual and intra-species heterogeneity in nuclear rDNA ITS region of Vigna species from subgenus Ceratotropis." Genetics Research 90, no. 4 (2008): 299–316. http://dx.doi.org/10.1017/s001667230800983x.

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SummaryThe extent of intra-individual and intra-species heterogeneity in the nuclear rDNA internal transcribed spacer (ITS) was investigated among the ‘Asiatic Vigna’ species (subgenus Ceratotropis). High intra- and inter-individual ITS polymorphism was observed among Vigna radiata accessions, where multiple ITS length variants ranging from ~700 to ~770 bp were detected on PCR amplification. Subsequent analysis revealed that the variants are ‘heteroduplex ITS fragments’ generated during the PCR process. Analysis of ITS from wild and cultivated forms of ten Vigna species from subgenus Ceratotro

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