scholarly journals Investigation of DNA denaturation from generalized Morse potential

2018 ◽  
Vol 3 (2) ◽  
Author(s):  
R. El Kinani ◽  
H. Kaidi ◽  
M. Benhamou
Keyword(s):  
Morse Potential ◽  
Bound States ◽  
Analytical Study ◽  
Free Energy Density ◽  
Exact Expression ◽  
Dna Denaturation ◽  
Denaturation Temperature ◽  
Finite Distance ◽  
The Mean ◽  
Generalized Morse Potential

In this paper, we present a non-linear model for the study of DNA denaturation transition. To this end, we assume that the double-strands DNA interact via a realistic generalized Morse potential that reproduces well the features of the real interaction. Using the Transfer Matrix Method, based on the resolution of a Schrödinger equation, we first determine exactly their solution, which are found to be bound states. Second, from an exact expression of the ground state, we compute the denaturation temperature and the free energy density, in terms of the parameters of the potential.Then, we calculate the contact probability, which is the probability to find the double-strands at a (finite) distance apart, from which we determine the behaviour of the mean-distance between DNA-strands.The main conclusion is that, the present analytical study reveals that the generalized Morse potential is a good candidate for the study of DNA denaturation

scholarly journals Rigorous Study of the Unbinding Transition of Biomembranes and Strings from Morse Potentials

2013 ◽  
Vol 2013 ◽  
pp. 1-7
Author(s):  
Mabrouk Benhamou ◽  
Radouane El Kinani ◽  
Hamid Kaidi
Keyword(s):  
Morse Potential ◽  
Bound States ◽  
State Energy ◽  
Free Energy Density ◽  
Bilayer Membranes ◽  
Realistic Potential ◽  
Exact Ground State ◽  
Rigorous Study ◽  
Generalized Morse Potential ◽  
Morse Potentials

The purpose is an exact study of the unbinding transition from two interacting manifolds (strings or bilayer membranes). These systems have similar scaling behavior, and then it is sufficient to consider only the strings’ problem. We assume that the manifolds interact via a realistic potential of Morse type. To this end, the use is made of the transfer matrix method, based on the resolution of a Schrödinger equation. We first determine the associated bound states and energy spectrum. Second, the exact ground state energy gives the free energy density, from which we extract the expression of the unbinding temperature. Third, we determine the contact probability between manifolds, from which we compute the (diverging) average separation and roughness of the manifolds. It is found that their critical behavior is close to that obtained using Field-Theoretical Renormalization-Group. The conclusion is that these analytical studies reveal that the Morse potential is a good candidate for the study of the unbinding phenomenon within manifolds. Finally, the discussion is extended to generalized Morse potential.

The focusing of radiation by a random surface when the source is at a finite distance

1960 ◽  
Vol 56 (1) ◽  
pp. 27-40 ◽  
Author(s):  
M. S. Longuet-Higgins
Keyword(s):  
Mean Curvature ◽  
Joint Distribution ◽  
Total Curvature ◽  
Statistical Distribution ◽  
Constant Parameter ◽  
Random Surface ◽  
Second Derivatives ◽  
Finite Distance ◽  
The Mean ◽  
Image Position

Imagine a nearly horizontal, statistically uniform, random surface ζ(x, y), Gaussian in the sense that the second derivatives , , have a normal joint distribution. The problem considered is the statistical distribution of the quantitywhere J and Ω denote the mean curvature and total curvature of the surface, respectively, and ν is a constant parameter.

scholarly journals Relationship between Body Mass Index and Tooth Decay in a Population of 3–6-Year-Old Children in Iran

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Leila Shafie Bafti ◽  
Maryam Alsadat Hashemipour ◽  
Hamidreza Poureslami ◽  
Zeinab Hoseinian
Keyword(s):  
Body Weight ◽  
Analytical Study ◽  
Deciduous Teeth ◽  
Tooth Decay ◽  
Cross Sectional ◽  
Dmft Index ◽  
The Mean ◽  
Iranian Children ◽  
The Relationship

The aim of the present study was to evaluate the relationship between BMI and tooth decay in a population of Iranian children. In this cross-sectional descriptive/analytical study, 1482 children were selected from kindergartens and preschool centers in Kerman, Iran. The children underwent examination of deciduous teeth (using the dmft index) after determination of height and weight for calculation of BMI. The relationship between BMI (after adjustment for age) and dmft was determined using Poisson’s regression model. The mean of dmft in children with normal BMI was 1.5-fold that in subjects with extra body weight. Age had a significant effect on dmft. In addition, dmft was higher in boys compared to girls. The results of the present study showed that caries rate in the deciduous teeth of 3–6-year-old children decreases with an increase in body weight.

scholarly journals Perubahan nilai laktat serum dan nilai leukosit pasca penanganan pasien multitrauma

2016 ◽  
Vol 8 (2) ◽  
Author(s):  
Jimmy Koan ◽  
Laurens T. B. Kalesaran ◽  
Heber B. Sapan
Keyword(s):  
Blood Lactate ◽  
Analytical Study ◽  
Early Stage ◽  
Cellular Level ◽  
Metabolic Changes ◽  
T Test ◽  
Laboratory Markers ◽  
The Mean ◽  
Paired T Test

Abstract: Available laboratory markers in the early stage of injury are very helpful for the clinicians to predict the diturbances in cellular level concerning prevention of early decompensation, therefore, vital condition of the patient can improve faster. Lactate and leucocyte levels are assumed as sensitive markers of metabolic changes that occur at the time of injury. This study aimed to obtain the changes of lactate and leukocyte levels in multitraumatic patients after resusitation at Prof. Dr. R. D. Kandou Hospital Manado from August to September 2015. This was an observational analytical study. The results showed that there were 36 multitraumatic patients in this study, consisted of 27 males and 9 females. One patient died during this study. The mean decrease of blood lactate was 1.4611 mmol/L, meanwhile, of leukocytes was 5582.2000/mm3. The paired T test showed very significant changes of blood lactate and leukocyte levels (P < 0.001) after resusitation. Conclusion: Achievement of resusitation and improvement in cellular level could be monitored by using lactate and leukocyte levels after resusitation of multitraumatic patients although the definitive aim of the trauma was not final yet.Kata kunci: lactate, leukocyte, multitraumatic patientsAbstrak: Tersedianya penanda laboratorik pada fase awal cedera dapat memudahkan klinisi memrediksi kelainan yang terjadi di tingkat sel untuk mencegah terjadinya fase dekompensasi secara dini sehingga dapat memperbaiki kondisi vital pasien dengan segera. Kadar laktat dan jumlah leukosit telah lama dianggap sebagai salah satu penanda yang sensitif terhadap perubahan metabolisme yang terjadi saat cedera. Penelitian ini bertujuan untuk mengetahui perubahan nilai serum laktat dan leukosit darah yang terjadi pada pasien multitrauma setelah penanganan di RSUP Prof. Dr. R. D. Kandou Manado sejak bulan Agustus sampai dengan September 2015. Jenis penelitian ini observasional analitik dengan desain potong lintang. Hasil penelitian memperlihatkan terdapat 36 pasien multitrauma, terdiri dari 27 laki-laki dan 9 perempuan. Selama penelitian didapatkan 1 pasien meninggal saat penanganan. Pada pasca penanganan, rerata penurunan nilai asam laktat darah sebesar 1,4611 mmol/L dan nilai leukosit sebesar 5582,2000/mm3. Hasil uji T berpasangan memperlihatkan perubahan nilai laktat darah dan leukosit pasca penanganan yang sangat bermakna (P < 0,001). Simpulan: Tercapainya resusitasi dan perbaikan di tingkat sel dapat dimonitor dari nilai laktat dan leukosit darah pasca penanganan pasien multitrauma walaupun penanganan belum sampai pada tujuan definitif trauma.Kata kunci: asam laktat, leukosit, multitrauma

Alignment of carbon nanotubes under the influences of nematic liquid crystals and electric fields — an analytical study

2021 ◽  
Author(s):  
Setia Budi Sumandra ◽  
Bhisma Mahendra ◽  
Fahrudin Nugroho ◽  
Yusril Yusuf
Keyword(s):  
Carbon Nanotubes ◽  
Free Energy ◽  
Electric Field ◽  
Electric Fields ◽  
Analytical Study ◽  
Free Energy Density ◽  
Diameter Ratio ◽  
Order Parameters ◽  
Anchoring Strength ◽  
Length To Diameter Ratio

Carbon nanotubes (CNTs) have benefits in various fields, they are disadvantageous due to their tendency to form aggregates and poorly controlled alignment of the CNT molecules (characterized by order parameters). These deficiencies can be overcome by dispersing the CNTs in nematic liquid crystal (LC) and placing the mixture under the influence of an electric field. In this study, Doi and Landau–de Gennes free energy density equations are used to analytically confirm that an electric field increases the order parameters of CNTs and LCs in a dispersion mixture. The anchoring strength of the nematic LC is also found to affect the order parameters of the CNTs and LC. Further, increasing the length-to-diameter ratio of the CNTs increases their alignment without affecting the LC alignment. These findings indicate that CNT molecular alignment can be controlled by adjusting the CNT length-to-diameter ratio, anchoring the LCs, and adjusting the electric field strength.

scholarly journals A New Generalized Morse Potential Function for Calculating Cohesive Energy of Nanoparticles

Energies ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3323 ◽  
Author(s):  
Omar M. Aldossary ◽  
Anwar Al Rsheed
Keyword(s):  
Potential Function ◽  
Cohesive Energy ◽  
Morse Potential ◽  
Attractive Force ◽  
Repulsive Interaction ◽  
Additional Parameter ◽  
Generalized Potential ◽  
The Stability ◽  
Experimental Values ◽  
Generalized Morse Potential

A new generalized Morse potential function with an additional parameter m is proposed to calculate the cohesive energy of nanoparticles. The calculations showed that a generalized Morse potential function using different values for the m and α parameters can be used to predict experimental values for the cohesive energy of nanoparticles. Moreover, the enlargement of the attractive force in the generalized potential function plays an important role in describing the stability of the nanoparticles rather than the softening of the repulsive interaction in the cases when m > 1.

Über das Dissoziationsgleichgewicht realer Gase

1966 ◽  
Vol 21 (3) ◽  
pp. 252-255
Author(s):  
H. Koppe ◽  
G. Spies
Keyword(s):  
Cross Sections ◽  
Bound States ◽  
Exact Expression ◽  
Mass Action ◽  
Quantum Mechanical ◽  
Law Of Mass Action ◽  
Vibrational States ◽  
Degree Of Dissociation ◽  
Atom Scattering ◽  
Collision Approximation

The quantum mechanical cluster expansion, when applied to the partition function of a gas consisting of atoms whose bound states are the rotational and vibrational states of diatomic molecules, provides an exact expression for the degree of dissociation. The approximation containing only the second cluster integral is shown to be identical with the law of mass action involving the binary collision approximation for the activity coefficient of the dissociated constituent. This coefficient can be calculated from the phase shifts and thus from the cross sections of the elastic atom-atom-scattering.

scholarly journals Model reduction by mean-field homogenization in viscoelastic composites. II. Application to rigidly reinforced solids

2020 ◽  
Vol 476 (2242) ◽  
pp. 20200408
Author(s):  
Martín I. Idiart ◽  
Noel Lahellec ◽  
Pierre Suquet
Keyword(s):  
Elastic Moduli ◽  
Solid Phase ◽  
Mean Field ◽  
Free Energy Density ◽  
Companion Paper ◽  
Viscoelastic Solid ◽  
Complex Deformation ◽  
Link Type ◽  
The Mean ◽  
Viscoelastic Composites

The mean-field homogenization scheme proposed by Lahellec & Suquet (2007 Int. J. Solids Struct. 44 , 507–529 ( doi:10.1016/j.ijsolstr.2006.04.038 )) and revisited in a companion paper (Idiart et al . 2020 Proc. R. Soc. A 20200407 ( doi:10.1098/rspa.2020.0407 )) is applied to random mixtures of a viscoelastic solid phase and a rigid phase. Two classes of mixtures with different microstructural arrangements are considered. In the first class the rigid phase is dispersed within the continuous viscoelastic phase in such a way that the elastic moduli of the mixture are given exactly by the Hashin–Shtrikman formalism. In the second class, both phases are intertwined in such a way that the elastic moduli of the mixture are given exactly by the Self-Consistent formalism. Results are reported for specimens subject to various complex deformation programmes. The scheme is found to improve on earlier approximations of common use and even recover exact results under several circumstances. However, it can also generate highly inaccurate predictions as a result of the loss of convexity of the free-energy density. An auspicious procedure to partially circumvent this issue is advanced.

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