Conformational, electronic, and spectroscopic characterization of isophthalic acid (monomer and dimer structures) experimentally and by DFT.

Isophthalic acid (C6H4(CO2H)2) is a noteworthy organic compound widely used in coating and synthesis of resins and the production of commercially important polymers such as drink plastic bottles. The effects of isophthalic acid (IPA) on human health, toxicology, and biodegradability are the main focus of many researchers. Because structural and spectroscopic investigation of molecules provides a deep understanding of interactional behaviors of compounds, this study stands for exploring those features. Therefore, the spectroscopic, structural, electronic, and thermodynamical properties of IPA were thoroughly studied in this work experimentally using UV-Vis, (1)H and (13)C NMR, FT-IR, FT-Raman and theoretically via DFT and TD-DFT calculations. The UV-Vis absorption spectrum in water was taken in the region 200-400nm. The NMR chemical shifts ((1)H and (13)C) were recorded in DMSO solution. The infrared and Raman spectra of the solid IPA were recorded in the range of 4000-400cm(-1) and 3500-50cm(-1), respectively. DFT and TD-DFT calculations were performed at the level of B3LYP/6-311++G(d,p) in determination of geometrical structure, electronic structure analysis and normal mode. The (13)C and (1)H nuclear magnetic resonance (NMR) spectra were estimated by using the gauge-invariant atomic orbital (GIAO) method. The scaled quantum mechanics (SQM) method was used to determine the total energy distribution (TED) to assign the vibrational modes accurately. Weak interactions such as hydrogen bonding and Van der Walls were analyzed via reduced density gradient (RDG) analysis in monomeric and dimeric forms. Furthermore, the excitation energies, density of state (DOS) diagram, thermodynamical properties, molecular electro-static potential (MEP), and nonlinear optical (NLO) properties were obtained.

DFT calculations and experimental FT-IR, FT-Raman, NMR, UV-Vis spectral studies of 3-fluorophenylboronic acid.

The spectroscopic (FT-IR, FT-Raman, (1)H and (13)C NMR, UV-Vis), structural, electronic and thermodynamical properties of 3-fluorophenylboronic acid (C6H4FB(OH)2), 3FPBA) were submitted by using both experimental techniques and theoretical methods (quantum chemical calculations) in this work. The experimental infrared and Raman spectra were obtained in the region 4000-400 cm(-1) and 3500-10 cm(-1), respectively. The equilibrium geometry and vibrational spectra were calculated by using DFT (B3LYP) with 6-311++G(d,p) basis set. The vibrational wavenumbers were also corrected with scale factor to take better results for the calculated data. The total energy distributions (TED) of the vibrational modes were performed for the assignments of the title molecule by using scaled quantum mechanics (SQM) method. The NMR chemical shifts ((1)H and (13)C) were recorded in DMSO solution. The (1)H and (13)C NMR spectra were computed by using the gauge-invariant atomic orbital (GIAO) method, showing a good agreement with the experimental ones. The last one UV-Vis absorption spectra were analyzed in two solvents (ethanol and water), saved in the range of 200-400 nm. In addition these, HOMO and LUMO energies, the excitation energies, density of states (DOS) diagrams, thermodynamical properties and molecular electrostatic potential surface (MEPs) were presented. Nonlinear optical (NLO) properties and thermodynamic features were performed. The experimental results are combined with the theoretical calculations using DFT calculations to fortification of the paper. At the end of this work, the results were proved our paper had been indispensable for the literature backing.

FT-IR and FT-Raman, NMR and UV spectroscopic investigation and hybrid computational (HF and DFT) analysis on the molecular structure of mesitylene.

The spectroscopic properties of mesitylene were investigated by FT-IR, FT-Raman, UV, (1)H and (13)C NMR techniques. The geometrical parameters and energies have been obtained from density functional theory (DFT) B3LYP method and Hartree-Fock (HF) method with 6-311++G(d,p) and 6-311G(d,p) basis sets calculations. The geometry of the molecule was fully optimized, vibrational spectra were calculated and fundamental vibrations were assigned on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method and PQS program. Total and partial density of state (TDOS and PDOS) and also overlap population density of state (OPDOS) diagrams analysis were presented. (13)C and (1)H NMR chemical shifts were calculated by using the gauge-invariant atomic orbital (GIAO) method. The electronic properties, such as excitation energies, oscillator strength, wavelengths, HOMO and LUMO energies, were performed by time-dependent density functional theory (TD-DFT) results complements with the experimental findings. The results of the calculations were applied to simulate spectra of the title compound, which show excellent agreement with observed spectra. Besides, frontier molecular orbitals (FMO), molecular electrostatic potential (MEP) and thermodynamic properties were performed. Reduced density gradient (RDG) of the mesitylene was also given to investigate interactions of the molecule.

Determination of structural and vibrational spectroscopic features of neutral and anion forms of dinicotinic acid by using NMR, infrared and Raman experimental methods combined with DFT and HF.

In this study; the experimental (NMR, infrared and Raman) and theoretical (HF and DFT) analysis of dinicotinic acid were presented. (1)H and (13)C NMR spectra were recorded in DMSO solution and chemical shifts were calculated by using the gauge-invariant atomic orbital (GIAO) method. The vibrational spectra of dinicotinic acid were recorded by FT-Raman and FT-IR spectra in the range of 4000-10 cm(-1) and 4000-400 cm(-1), respectively. To determine the most stable neutral conformer of molecule, the selected torsion angle was changed every 10° and molecular energy profile was calculated from 0° to 360°. The geometrical parameters and energies were obtained for all conformers form from density functional theory (DFT/B3LYP) and HF with 6-311++G(d,p) basis set calculations. However, the results of the most stable neutral and two anion forms (anion(-1) and anion(-2) forms) of dinicotinic acid are reported here. The complete assignments were performed on the basis of the total energy distribution (TED) of the vibrational wavenumbers, calculated with scaled quantum mechanics (SQM) method and PQS program.

Coulomb excitation of 104Sn and the strength of the 100Sn shell closure.

A measurement of the reduced transition probability for the excitation of the ground state to the first 2+ state in 104Sn has been performed using relativistic Coulomb excitation at GSI. 104Sn is the lightest isotope in the Sn chain for which this quantity has been measured. The result is a key point in the discussion of the evolution of nuclear structure in the proximity of the doubly magic nucleus 100Sn. The value B(E2; 0+ → 2+) = 0.10(4) e2b2 is significantly lower than earlier results for 106Sn and heavier isotopes. The result is well reproduced by shell model predictions and therefore indicates a robust N = Z = 50 shell closure.

Superallowed Gamow-Teller decay of the doubly magic nucleus 100Sn.

The shell structure of atomic nuclei is associated with 'magic numbers' and originates in the nearly independent motion of neutrons and protons in a mean potential generated by all nucleons. During ß(+)-decay, a proton transforms into a neutron in a previously not fully occupied orbital, emitting a positron-neutrino pair with either parallel or antiparallel spins, in a Gamow-Teller or Fermi transition, respectively. The transition probability, or strength, of a Gamow-Teller transition depends sensitively on the underlying shell structure and is usually distributed among many states in the neighbouring nucleus. Here we report measurements of the half-life and decay energy for the decay of (100)Sn, the heaviest doubly magic nucleus with equal numbers of protons and neutrons. In the ß-decay of (100)Sn, a large fraction of the strength is observable because of the large decay energy. We determine the largest Gamow-Teller strength so far measured in allowed nuclear ß-decay, establishing the 'superallowed' nature of this Gamow-Teller transition. The large strength and the low-energy states in the daughter nucleus, (100)In, are well reproduced by modern, large-scale shell model calculations.

16+ spin-gap isomer in 96Cd.

A ß-decaying high-spin isomer in (96)Cd, with a half-life T(1/2)=0.29(-0.10)(+0.11) s, has been established in a stopped beam rare isotope spectroscopic investigations at GSI (RISING) experiment. The nuclei were produced using the fragmentation of a primary beam of (124)Xe on a (9)Be target. From the half-life and the observed γ decays in the daughter nucleus, (96)Ag, we conclude that the ß-decaying state is the long predicted 16(+) "spin-gap" isomer. Shell-model calculations, using the Gross-Frenkel interaction and the πν(p(1/2),g(9/2)) model space, show that the isoscalar component of the neutron-proton interaction is essential to explain the origin of the isomer. Core excitations across the N=Z=50 gaps and the Gamow-Teller strength, B(GT) distributions have been studied via large-scale shell-model calculations using the πν(g,d,s) model space to compare with the experimental B(GT) value obtained from the half-life of the isomer.

Evidence for a spin-aligned neutron-proton paired phase from the level structure of (92)Pd.

Shell structure and magic numbers in atomic nuclei were generally explained by pioneering work that introduced a strong spin-orbit interaction to the nuclear shell model potential. However, knowledge of nuclear forces and the mechanisms governing the structure of nuclei, in particular far from stability, is still incomplete. In nuclei with equal neutron and proton numbers (N = Z), enhanced correlations arise between neutrons and protons (two distinct types of fermions) that occupy orbitals with the same quantum numbers. Such correlations have been predicted to favour an unusual type of nuclear superfluidity, termed isoscalar neutron-proton pairing, in addition to normal isovector pairing. Despite many experimental efforts, these predictions have not been confirmed. Here we report the experimental observation of excited states in the N = Z = 46 nucleus (92)Pd. Gamma rays emitted following the (58)Ni((36)Ar,2n)(92)Pd fusion-evaporation reaction were identified using a combination of state-of-the-art high-resolution γ-ray, charged-particle and neutron detector systems. Our results reveal evidence for a spin-aligned, isoscalar neutron-proton coupling scheme, different from the previous prediction. We suggest that this coupling scheme replaces normal superfluidity (characterized by seniority coupling) in the ground and low-lying excited states of the heaviest N = Z nuclei. Such strong, isoscalar neutron-proton correlations would have a considerable impact on the nuclear level structure and possibly influence the dynamics of rapid proton capture in stellar nucleosynthesis.

Changes in nasal structures following orthopaedic and surgically assisted rapid maxillary expansion.

The aim of this study was to investigate and compare changes in the nasomaxillary complex substructures following orthopaedic rapid maxillary expansion (RME) and surgically assisted RME (SARME). 10 patients received RME, 10 patients received SARME, and 10 patients served as an untreated control group. Lateral and posteroanterior cephalograms were obtained for each individual at pre-expansion/pre-control (T1) and post-expansion/post-control (T2). Descriptive parameters and transversal measurements on maxillo-mandibular dentoalveolar structures and skeletal bases, right and left nasal cavity angles (NC/Lom/VL and CN/Lom/VL, respectively), total nasal cavity angle (NC/Lom/CN), nasal cavity width (NC-CN) and nasal septum angle (sn/Lom/VL) were also calculated. Paired t-tests were used to evaluate changes within groups following treatment/control. Analysis of variance (ANOVA) and Duncan's tests were used to compare changes between groups. With the exception of nasal septum deviation, all nasal parameters significantly increased following RME and SARME. The increases in the SARME group were greater than in the other groups, but no statistically significant differences were recorded between the RME and SARME groups. Neither RME nor SARME created positional changes in the nasal septum.

Single nucleotide polymorphism in esophageal cancer related gene 1: an analysis in resected oral squamous cell carcinoma patients.

Esophageal cancer related gene 1 (ECRG1) is a novel candidate tumor suppressor gene in human esophageal squamous cells. Overexpression of ECRG1 protein inhibits tumor cell proliferation. Genetic polymorphisms in coding sequences of the gene may cause functional alterations of the gene product and be associated with higher cancer risk and disease phenotypes. A single nucleotide polymorphism (SNP) (Arg290Gln) found in the coding region of ECRG1 might play a role in susceptibility to esophageal squamous cell carcinoma. This study examined SNPs in ECRG1 in a similar tumor type (oral squamous cell carcinoma; OSCC) and investigated the relationship between SNPs in ECRG1 and the clinical outcome of patients with OSCC. DNA samples of 137 OSCC patients were analyzed for SNP genotypes Arg/Arg, Arg/Gln and Gln/Gln in the coding region (exon 8) of ECRG1. SNP genotypes Arg/Arg were found in 70 (51%), Arg/Gln in 60 (43%) and Gln/Gln in 7 (5%) patients. There was no significant association between genotypes and survival (p=0.77) or relapse free survival (p=0.32). The Gln/Gln genotype had the best survival (not significant) probably due to rare cases of SNP Gln/Gln genotype. Genotype Arg/Arg might be a potential negative prognostic marker in OSCC, but more studies with higher patient numbers are required.

Experimental kerma coefficients for carbon deduced from microscopic cross sections at 96 MeV incident neutron energy.

The double-differential cross sections for (n, px), (n, dx), (n, tx), (n, 3Hex) and (n, alphax) reactions in carbon have been measured at 96 MeV incident neutron energy. The various charged particles (inclusive spectra) were identified using deltaE-E techniques. From the experimental data, energy- and angle-differential as well as production cross sections were determined, and subsequently the partial and total kerma coefficients. The deduced partial and total kerma coefficients were compared to previous experimental results and theoretical calculations. The findings indicate that the deduced kerma coefficients for the hydrogen isotopes are in good agreement with those deduced from a previous measurement, and that the kerma coefficient values, in particular of the hydrogen isotopes, are systematically higher than values obtained from recent model calculations, which consequently resulted in a total kerma coefficient which is up to 30% higher than predicted by the calculations.

Fluoride content of infant formulas and market milk in Turkey.

The aim of the present study was to test the fluoride contents of infant formulas and market milk in Turkey. Fifteen formulas and nine market milks were prepared according to manufacturers' instructions with deionized water. Fluoride contents were analyzed with a spectrophotometer (CADAS 50S) and results were obtained as ppm (microgF/ml). Mean fluoride content of the formulas was 0.101 ppm F and of the milks was 0.08 ppm F. Formulas reconstituted with water containing < 0.3 ppm F do not provide a daily fluoride intake at any age. To decrease dental caries among children in Turkey, fluoride supplements could be prescribed at minimal dosages according to the ADA fluoride schedule.

Expression of beta 1 integrins in human dental pulp in vivo: a comparative immunohistochemical study on healthy and chronic marginal periodontitis samples.

AIM: The objective of this study was to determine the tissue distribution of beta 1 integrin chains in sound human dental pulps and to compare the findings with connective tissue compartments of other organs and to pulp tissue in teeth extracted due to periodontal disease. METHODOLOGY: Freshly frozen pulp tissue samples from teeth extracted for orthodontic reasons were examined and compared to samples from teeth extracted due to chronic (marginal) periodontitis. beta 1 integrin chains were determined using an indirect-immunoperoxidase technique. Seven monoclonal antibodies recognizing alpha 1, alpha 2, alpha 3, alpha 4, alpha 5, alpha 6 and beta 1 chains of Very Late Activation Antigen (VLA) integrins were used for this purpose. RESULTS: VLA-1, VLA-2, VLA-3 and VLA-5 were expressed by vascular endothelium and vascular smooth muscle in varying intensities in both groups. VLA-6 reactivity was observed in the basal surfaces of arterial, venous and capillary endothelia. Our results indicate that there was no significant difference in the expression of VLA integrins in sound pulp tissue when compared to the samples from chronic (marginal) periodontitis and the connective tissue compartments of other viscera. CONCLUSION: The present findings suggest that human dental pulp tissue is not different from other connective tissue compartments in the body with respect to VLA integrin expression, and chronic marginal periodontitis does not affect pulp tissue to a histopathologically detectable extent.

Investigation of the ototoxic effects of interferon alpha2A on the mouse cochlea.

This prospective randomized study investigates the possible toxic effects of interferon (IFN) alpha2A on the mouse cochlea. Thirty-six albino Swiss mice that were randomly assigned to 3 groups underwent baseline auditory brain stem response testing bilaterally to objectively assess baseline hearing levels. The first group received a single dose of 50,000 units, and the second group received 100,000 units of IFN-alpha2A intraperitoneally, whereas the third group was given no medication. Repeat auditory brain stem response testing revealed a significant rise in mean baseline peak equivalent sound pressure level thresholds in the groups that received IFN (P < 0.001). Histologically, the cochleae of mice that received IFN had a decreased number of fibroblasts in the spiral limbus, as well as prominent cytoplasmic vacuolation of these cells, compared with control animals. Loss of hair cells was not observed. It is possible that reversible biochemical and metabolic changes in the cochlea, rather than morphologic abnormalities, manifest IFN ototoxicity.

Two male patients with nevoid basal cell carcinoma syndrome from Turkey.

Nevoid basal cell carcinoma syndrome, also known as Gorlin's syndrome, is a familial autosomal dominant syndrome characterized by multiple basal cell carcinomas, multiple odontogenic keratocysts of the jaws, and skeletal anomalies. Both tumors and malformations of the central nervous system occur with nevoid basal cell carcinoma. Medulloblastoma is the primary brain tumor most frequently associated with this syndrome. The authors report in this article two male patients with nevoid basal cell carcinoma syndrome: a 22-year-old male patient with multiple odontogenic keratocysts, who had medulloblastoma at two years and multiple basal cell carcinoma at 10 years of age, and a 15-year-old male patient with skeletal abnormalities and multiple odontogenic keratocysts in the jaws.

Antibacterial activity of fifth-generation dentin bonding systems.

Past concepts that the pulp does not become infected until an actual carious exposure takes place have been challenged. The antibacterial effects of the dentin bonding systems Single Bond, Prime&Bond NT, and Excite were evaluated using the bacteria Streptococcus mutans ATCC 25175, Streptococcus intermedius, Lactobacillus acidophilus, Prevotella oris, Prevotella bivia, Prevotella denticola, Porphyromonas gingivalis, Porphyromonas endodontalis, and Clostridium ramosum with a disk diffusion method. Chlorhexidine (0.2%) was used as a positive control. After incubation zones of inhibited bacterial growth were measured. Prime&Bond NT showed growth inhibition for all bacterial strains. Lactobacillus acidophilus and Streptococcus mutans were remarkably resistant to Single Bond, whereas EX produced no inhibitory effect on Porphyromonas endodontalis, although the adhesive produced the maximum halo inhibition to Streptococcus mutans (15+/-1 mm), showing an antibacterial effect closest to chlorhexidine. The variety of results obtained in this study suggest that antibacterial properties of current dentin adhesives may depend on components that are originally incorporated to promote adhesion.

Endothelial cell and stromal antigens in human periapical granulation tissue.

Periapical granulation tissue consists of vasculature of varying sizes and types, infiltrating cells, and other stromal elements. We examined the differential expression of endothelial and stroma antigens in this tissue to determine their tissue distribution in order to obtain hints on their functions. Some of the antigens examined were present only in the endothelial lining of vasculature, including high endothelial venules (e.g. CD31 and CD105), whereas others were more widely expressed by both vascular and stromal elements (e.g. CD29, CD63, CD44, and CD151). Immunohistochemical analysis using monoclonal antibodies specific to certain tissue compartments revealed the tissue architecture more precisely and the expression of certain antigens in the tissue suggested special roles for these antigens. Tissue distribution of CD63, CD143, CD147, and CD151 in periapical granulation tissue is first reported in the present study.

CD45/isotypes expression in the immune cells of human periapical lesions.

Expression of some leukocyte antigens (including CD45) and its isoforms (CD2, CD4, CD5, CD6, CD7, and CD8) was examined in the human periapical granulation tissue samples in the present study. The majority of the infiltrating cells expressed heavy molecular-weight isoforms of the CD45 antigen. Expression of CD2, CD5, CD6, and CD7 antigens was also detected, implying significant roles for these antigens in the immune reaction taking place in periapical lesions. This suggests that the immune response taking place at the periapical region is predominantly cellular and the humoral responses to antigenic challenge are conducted mainly by regional lymph nodes.

Endothelial cell adhesion molecules in human dental pulp: a comparative immunohistochemical study on chronic periodontitis.

Migration of leukocytes to inflammation sites through vascular endothelium is controlled by the interactions of adhesion molecules expressed on both endothelial cells and leukocytes, most of which are already covered by cluster of differentiation (CD) codes. We examined the expression of a variety of endothelial cell adhesion molecules in human dental pulp vasculature to obtain further evidence on the tissue distribution and function of these molecules by using an indirect immunoperoxidase technique. We obtained the pulp tissue samples from teeth extracted due to orthodontic reasons as controls and compared with those extracted due to chronic periodontitis. In all samples, both CD31 and CD146 were expressed by arterial, venous, and capillary endothelia. There was no significant difference between the staining intensity of normal and inflamed pulp tissues. CD102 expression on the endothelium was significantly stronger in chronic periodontitis pulp samples. CD106, CD62-E, CD62-P, CD105, and CD54 were variably expressed in control and chronic periodontitis groups. Our results indicate that CD102 represents the major endothelial cell adhesion molecule probably involved in the inflammatory reactions in chronic periodontitis.