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1.
J Chem Phys ; 158(8): 084102, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36859092

ABSTRACT

In this paper, we propose to compute the electronic circular dichroism (ECD) spectra of chiral molecules using a real-time propagation of the time-dependent Schrödinger equation (TDSE) in the space of electronic field-free eigenstates, by coupling TDSE with a given treatment of the electronic structure of the target. The time-dependent induced magnetic moment is used to compute the ECD spectrum from an explicit electric perturbation. The full matrix representing the transition magnetic moment in the space of electronic states is generated from that among pairs of molecular orbitals. In the present work, we show the ECD spectra of methyloxirane, of several conformers of L-alanine, and of the Λ-Co(acac)3 complex, computed from a singly excited ansatz of time-dependent density functional theory eigenstates. The time-domain ECD spectra properly reproduce the frequency-domain ones obtained in the linear-response regime and quantitatively agree with the available experimental data. Moreover, the time-domain approach to ECD allows us to naturally go beyond the ground-state rotationally averaged ECD spectrum, which is the standard outcome of the linear-response theory, e.g., by computing the ECD spectra from electronic excited states.

2.
J Chem Phys ; 159(12)2023 Sep 28.
Article in English | MEDLINE | ID: mdl-38127378

ABSTRACT

Quantum-chemistry methods in the time domain with Gaussian basis sets are increasingly used to compute high-harmonic generation (HHG) spectra of atomic and molecular systems. The quality of these approaches is limited by the accuracy of Gaussian basis sets to describe continuum energy states. In the literature, optimal-continuum Gaussian basis sets have been proposed: Kaufmann et al. [J. Phys. B: At., Mol. Opt. Phys. 22, 2223 (1989)], Wozniak et al. [J. Chem. Phys. 154, 094111 (2021)], Nestmann and Peyerimhoff [J. Phys. B: At., Mol. Opt. Phys. 23, L773 (1990)], Faure et al. [Comput. Phys. Commun. 144, 224 (2002)], and Krause et al. [J. Chem. Phys. 140, 174113 (2014)]. In this work, we have compared the performances of these basis sets to simulate HHG spectra of H atom at different laser intensities. We have also investigated different strategies to balance basis sets with these continuum functions, together with the role of angular momentum. To quantify the performance of the different basis sets, we introduce local and global HHG descriptors. Comparisons with the grid and exact calculations are also provided.

3.
J Chem Phys ; 153(20): 200901, 2020 Nov 28.
Article in English | MEDLINE | ID: mdl-33261492

ABSTRACT

The multidisciplinary nature of the research in molecular nanoplasmonics, i.e., the use of plasmonic nanostructures to enhance, control, or suppress properties of molecules interacting with light, led to contributions from different theory communities over the years, with the aim of understanding, interpreting, and predicting the physical and chemical phenomena occurring at molecular- and nano-scale in the presence of light. Multiscale hybrid techniques, using a different level of description for the molecule and the plasmonic nanosystems, permit a reliable representation of the atomistic details and of collective features, such as plasmons, in such complex systems. Here, we focus on a selected set of topics of current interest in molecular plasmonics (control of electronic excitations in light-harvesting systems, polaritonic chemistry, hot-carrier generation, and plasmon-enhanced catalysis). We discuss how their description may benefit from a hybrid modeling approach and what are the main challenges for the application of such models. In doing so, we also provide an introduction to such models and to the selected topics, as well as general discussions on their theoretical descriptions.

4.
Int J Legal Med ; 133(5): 1529-1536, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31197452

ABSTRACT

In this cross-sectional study, the accuracy of Cameriere's European formula was tested and a new specific model was developed for two samples of black and white South African children with known age and sex. For these purposes, 970 children of black South African ethnicity (girls 491, boys 479) and 974 with European ethnicity, living in South Africa (girls 493, boys 481), were retrospectively analyzed. The application of the European formula showed that there is a trend in the error estimates: the ages of the younger children are overestimated and those of the older children are underestimated, in both white and black children. A new model, based on the relationship between the apical width and the tooth length (maturity index) of the seven permanent mandibular teeth, was therefore constructed. The new developed equation for the South African population was able to explain 76% of total variance in white girls and 80% in white boys' subgroup. On the other side, the model explained 76% of total variance in black girls and 78% in the black boys' subgroup. The mean absolute error of the residuals (residuals = predicted age minus observed age) ranged from 0.718 to 0.769 years, with the interquartile range (IQRres) ranging from 1.19 to 1.31 years. Differently from the Cameriere's European formula, the plot did not tend to underestimate the chronological age significantly as the age increases. Cameriere's maturity index is reproducible in both samples of South African black and white children, for forensic purposes, and the Bayesian calibration approach is useful for a more accurate and precise estimation.


Subject(s)
Age Determination by Teeth/methods , Dentition, Permanent , Mandible/growth & development , Models, Statistical , Tooth Apex/growth & development , Adolescent , Bayes Theorem , Black People , Child , Cross-Sectional Studies , Female , Forensic Dentistry , Humans , Male , Mandible/diagnostic imaging , Radiography, Panoramic , South Africa/ethnology , Tooth Apex/diagnostic imaging , White People
5.
Int J Legal Med ; 132(5): 1457-1464, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29520486

ABSTRACT

AIMS: The evaluation of the cutoff value of I3M = 0.08 for discriminating black South African minors from adults, and its relationship with chronological age. MATERIAL AND METHODS: A sample of 833 panoramic radiographs of healthy black South African subjects (500 females and 333 males), in the age range of 14 to 24 years (mean age 17.67 years in females and 17.42 years in males), was retrospectively evaluated. RESULTS: ICC values were 99.10% (95% CI 97.70 to 99.70%) and 99.20% (95% CI 98.00 to 99.60%), for the intra- and inter-observer reliability, respectively. I3M decreased as the real age gradually increased in both sexes. According to the logistic regression model, the variable sex was not significant when the probability that an individual is 18 years or older was calculated. The I3M = 0.08 was valuable in discriminating between adults and minors. The overall accuracy (ACC = fraction of accurately classified subjects) is 0.90 (95% CI 0.87-0.91); the proportion of correctly classified subjects (Se = sensitivity) is 0.80 (95% CI 0.76-0.84), and specificity (Sp) is 0.95 (95% CI 0.93-0.97). The PPV (predictive positive value) is 0.96 (95% CI 0.95-0.97), and the negative predictive value is 0.76 (95% CI 0.72-0.80). CONCLUSION: The results show that I3M is a valuable method to distinguish subjects who are around legal adult age in South Africa.


Subject(s)
Age Determination by Teeth , Black People , Forensic Dentistry , Molar, Third , Adolescent , Adult , Female , Humans , Male , Radiography, Panoramic , Reproducibility of Results , Retrospective Studies , South Africa , Young Adult
6.
J Biol Regul Homeost Agents ; 32(6): 1605-1608, 2018.
Article in English | MEDLINE | ID: mdl-30574773

ABSTRACT

OAtrophic maxilla is a challenge in dental implant surgery, and new strategies are needed. We present a new minimally-invasive approach, called "Spider Zygoma", consisting of implant-supported prosthesis with the addition of customized maxillofacial plates and screws on surface of zygomatic bone. A 3D-model of the edentulous upper jaw was used as preoperative model. Two customized bone plates were created and used as guide for placement of implants and zygomatic screws. Although this is only a pilot study, this new surgical technique seems to be safe and accurate, confirmed by the maintenance of good aesthetic and functional results after 5-year follow-up.


Subject(s)
Dental Implantation, Endosseous/methods , Dental Implants , Dental Prosthesis, Implant-Supported , Maxilla/surgery , Zygoma/surgery , Humans , Pilot Projects
7.
Fish Physiol Biochem ; 40(2): 577-93, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24078221

ABSTRACT

Largely attributable to concerns surrounding sustainability, the utilisation of omega-3 long-chain polyunsaturated fatty acid-rich (n-3 LC-PUFA) fish oils in aquafeeds for farmed fish species is an increasingly concerning issue. Therefore, strategies to maximise the deposition efficiency of these key health beneficial fatty acids are being investigated. The present study examined the effects of four vegetable-based dietary lipid sources (linseed, olive, palm and sunflower oil) on the deposition efficiency of n-3 LC-PUFA and the circulating blood plasma concentrations of the appetite-regulating hormones, leptin and ghrelin, during the grow-out and finishing phases in rainbow trout culture. Minimal detrimental effects were noted in fish performance; however, major modifications were apparent in tissue fatty acid compositions, which generally reflected that of the diet. These modifications diminished somewhat following the fish oil finishing phase, but longer-lasting effects remained evident. The fatty acid composition of the alternative oils was demonstrated to have a modulatory effect on the deposition efficiency of n-3 LC-PUFA and on the key endocrine hormones involved in appetite regulation, growth and feed intake during both the grow-out and finishing phases. In particular, n-6 PUFA (sunflower oil diet) appeared to 'spare' the catabolism of n-3 LC-PUFA and, as such, resulted in the highest retention of these fatty acids, ultimately highlighting new nutritional approaches to maximise the maintenance of the qualitative benefits of fish oils when they are used in feeds for aquaculture species.


Subject(s)
Dietary Fats, Unsaturated/administration & dosage , Dietary Fats, Unsaturated/pharmacokinetics , Fatty Acids, Omega-3/administration & dosage , Fatty Acids, Omega-3/pharmacokinetics , Ghrelin/blood , Oncorhynchus mykiss/growth & development , Oncorhynchus mykiss/physiology , Animal Feed/analysis , Animals , Diet , Fatty Acids/chemistry , Fatty Acids/metabolism , Fish Oils/administration & dosage , Fish Oils/pharmacokinetics , Fish Proteins/blood , Fisheries , Leptin/blood , Plant Oils/administration & dosage , Plant Oils/pharmacokinetics
8.
J Phys Chem Lett ; 14(7): 1941-1948, 2023 Feb 23.
Article in English | MEDLINE | ID: mdl-36787099

ABSTRACT

Effects of the conformational dynamics of 2-PET protective ligands on the electronic circular dichroism (ECD) of the chiral Au38(SC2H4Ph)24 cluster are investigated. We adopt a computational protocol in which ECD spectra are calculated via the first principle polTDDFT approach on a series of conformations extracted from MD simulations by using Essential Dynamics (ED) analysis, and then properly weighted to predict the final spectrum. We find that the experimental spectral features are well reproduced, whereas significant discrepancies arise when the spectrum is calculated using the experimental X-ray structure. This result unambiguously demonstrates the need to account for the conformational effects in the ECD modeling of chiral nanoclusters. The present procedure proved to be able of capturing the essential conformational features of the dynamic Au38(SC2H4Ph)24 system, opening the possibility to model the ECD of soluble chiral nanoclusters in a realistic way.

9.
Minerva Stomatol ; 61(9): 355-65, 2012 Sep.
Article in English, Italian | MEDLINE | ID: mdl-22976564

ABSTRACT

AIM: The aim of this study was to investigate the retention values and mode of failure of metal crowns and fibre-reinforced composite crowns. METHODS: Seventy-five implants and the corresponding abutments were used. After the galvanic copings were fabricated, the specimens were distributed into three groups: in group A traditional metal crowns were realized, whereas in groups B and C fibre-reinforced composite crowns were made. In group B the same resin based cement used in group A was employed for luting the fibre-reinforced composite crowns to the galvanic copings, while in group C a dedicated self-adhesive composite cement was used. All galvanic coping/crown assemblies were cemented onto abutments with Panavia 21 cement. Specimens were subjected to a pull-out test; median retentive values and standard deviations were calculated. RESULTS: All samples in the group A showed separation at the abutment-galvanic cap interface. All samples in the group B showed decementation at galvanic cap-crown interface. In 13 samples of the group C the decementation occurred at the abutment-galvanic cap interface and in 12 samples of this group the decementation occurred at the galvanic cap-crown interface. The mean retention value was 659.1 N±162.9 for group A, 304.7 N±101.4 for B and 635.4 N±155.9 for C. Differences between groups A/B and B/C are statistically significant (t-student test, P<0.01), while is not statistically different between groups A/C. CONCLUSION: When a self-adhesive composite cement is used, fibre-reinforced composite single crowns and conventional metal crowns show similar retentive performance.


Subject(s)
Crowns , Dental Abutments , Dental Prosthesis Retention , Dental Prosthesis Design , In Vitro Techniques
10.
Sci Rep ; 12(1): 19978, 2022 Nov 20.
Article in English | MEDLINE | ID: mdl-36404312

ABSTRACT

The eruption of the Hunga-Tonga volcano in the South Pacific Ocean on January 15, 2022, at about 4:15 UTC, generated a violent explosion, which created atmospheric pressure disturbances in the form of Rayleigh-Lamb waves detected all over the globe. Here we discuss the observation of the Hunga-Tonga shock-wave performed at the Ny-Ålesund Research Station on the Spitsbergen island, by the detectors of the PolarquEEEst experiment and their ancillary sensors. Online pressure data as well as the results of dedicated offline analysis are presented and discussed in details. Results include wave arrival times, wave amplitude measurements and wave velocity calculation. We observed five passages of the shock wave with a significance larger than 3 [Formula: see text] and an amplitude up to 1 hPa. The average propagation velocity resulted to be (308 ± 0.6) m/s. Possible effects of the atmospheric pressure variation associated with the shock-wave multiple passages on the cosmic-ray rate at ground level are also investigated. We did not find any significant evidence of this effect.

11.
Minerva Ginecol ; 63(1): 47-70, 2011 Feb.
Article in Italian | MEDLINE | ID: mdl-21311420

ABSTRACT

Adhesions are the most frequent complication of abdominopelvic surgery, causing important short- and long-term problems, including infertility, chronic pelvic pain and a lifetime risk of small bowel obstruction. They also complicate future surgery with considerable morbidity and expense, and an important mortality risk. They pose serious quality of life issues for many patients with associated social and healthcare costs. Despite advances in surgical techniques, the healthcare burden of adhesion-related complications has not changed in recent years. Adhesiolysis remains the main treatment although adhesions reform in most patients. There is rising evidence, however, that surgeons can take important steps to reduce the impact of adhesions. A task force of Italian gynecologists with a specialist interest in adhesions having reviewed the current evidence on adhesions and considered the opportunities to reduce adhesions in Italy, have approved a collective consensus position. This consensus paper provides a comprehensive overview of adhesions and their consequences and practical proposals for actions that gynecological surgeons in Italy should take. As well as improvements in surgical technique, developments in adhesion-reduction strategies and new agents offer a realistic possibility of reducing adhesion formation and improving outcomes for patients. They should be adopted particularly in high risk surgery and in patients with adhesiogenic conditions. Patients also need to be better informed of the risks of adhesions.


Subject(s)
Gynecologic Surgical Procedures/adverse effects , Tissue Adhesions/etiology , Tissue Adhesions/prevention & control , Abdomen , Costs and Cost Analysis , Female , Humans , Risk Factors , Tissue Adhesions/complications , Tissue Adhesions/economics , Tissue Adhesions/epidemiology
12.
J Chem Theory Comput ; 17(10): 6314-6329, 2021 Oct 12.
Article in English | MEDLINE | ID: mdl-34486881

ABSTRACT

In this work, a theoretical and computational set of tools to study and analyze time-resolved electron dynamics in molecules, under the influence of one or more external pulses, is presented. By coupling electronic-structure methods with the resolution of the time-dependent Schrödinger equation, we developed and implemented the time-resolved induced density of the electronic wavepacket, the time-resolved formulation of the differential projection density of states (ΔPDOS), and of transition contribution map (TCM) to look at the single-electron orbital occupation and localization change in time. Moreover, to further quantify the possible charge transfer, we also defined the energy-integrated ΔPDOS and the fragment-projected TCM. We have used time-dependent density-functional theory (TDDFT), as implemented in ADF software, and the Bethe-Salpeter equation, as provided by MolGW package, for the description of the electronic excited states. This suite of postprocessing tools also provides the time evolution of the electronic states of the system of interest. To illustrate the usefulness of these postprocessing tools, excited-state populations have been computed for HBDI (the chromophore of GFP) and DNQDI molecules interacting with a sequence of two pulses. Time-resolved descriptors have been applied to study the time-resolved electron dynamics of HBDI, DNQDI, LiCN (being a model system for dipole switching upon highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) electronic excitation), and Ag22. The computational analysis tools presented in this article can be employed to help the interpretation of fast and ultrafast spectroscopies on molecular, supramolecular, and composite systems.

13.
J Phys Chem A ; 114(9): 3221-8, 2010 Mar 11.
Article in English | MEDLINE | ID: mdl-20099796

ABSTRACT

Small (4)He clusters doped with a single atomic impurity, (1)H, (2)H, and (3)H, have been studied via a quantum Monte Carlo approach with the intent of establishing their binding behavior in nanoscopic clusters. Our calculations find that the only trimer (x)H (He)(2), which exhibits a bound state, is that with the tritium dopant (x = 3), in agreement with previous calculations using hyperspherical coordinates in the adiabatic approximation. The lightest dopant (1)H is seen not to stabilize the small helium clusters, while (2)H and (3)H are weakly bound to this solvent: our computed exchange energies and probability distribution functions reveal the "heliophobic" nature of hydrogen, leading thus to a further confirmation, in the realm of nanoscopic-size systems like the helium droplets, of the well-known nonmixing and nonsolvating features of hydrogen in macroscopic liquid bulk helium.

14.
Appl Opt ; 49(25): 4780-90, 2010 Sep 01.
Article in English | MEDLINE | ID: mdl-20842804

ABSTRACT

In-vacuum Faraday isolators (FIs) are used in gravitational wave interferometers to prevent the disturbance caused by light reflected back to the input port from the interferometer itself. The efficiency of the optical isolation is becoming more critical with the increase of laser input power. An in-vacuum FI, used in a gravitational wave experiment (Virgo), has a 20 mm clear aperture and is illuminated by an almost 20 W incoming beam, having a diameter of about 5 mm. When going in vacuum at 10(-6) mbar, a degradation of the isolation exceeding 10 dB was observed. A remotely controlled system using a motorized lambda=2 waveplate inserted between the first polarizer and the Faraday rotator has proven its capability to restore the optical isolation to a value close to the one set up in air.

15.
J Chem Phys ; 130(9): 094906, 2009 Mar 07.
Article in English | MEDLINE | ID: mdl-19275423

ABSTRACT

Variable-size (4)He(N) clusters doped with a single p-H(2) molecule are studied here using variational and diffusion Monte Carlo calculations that show the highly quantum nature of the dopant and the solvent. Energetic and structural features extracted from our analysis reveal that the p-H(2) molecule behaves as a gentle perturber: The He droplets remain essentially liquidlike, with no evident structural change with respect to the pure ones. The p-H(2) dopant represents a kind of "competitor" for helium in the smaller droplets because it can replace the solvent adatoms; it also remains immersed in the cluster as N increases although located off-center within the droplet, while, finally, getting fully solvated in the larger droplets. The calculations are carried out up to N=100 as the largest number of solvent (4)He atoms and clearly show no evidence of either shell structuring or of "magic" numbers in the size of the smaller droplets.

16.
J Chem Phys ; 130(22): 224903, 2009 Jun 14.
Article in English | MEDLINE | ID: mdl-19530785

ABSTRACT

In this paper, we carry out variational Monte Carlo and diffusion Monte Carlo (DMC) calculations for Li(2)((1)Sigma(g) (+))((4)He)(N) and Li(2)((3)Sigma(u) (+))((4)He)(N) with N up to 30 and discuss in detail the results of our computations. After a comparison between our DMC energies with the "exact" discrete variable representation values for the species with one (4)He, in order to test the quality of our computations at 0 K, we analyze the structural features of the whole range of doped clusters. We find that both species reside on the droplet surface, but that their orientation is spin driven, i.e., the singlet molecule is perpendicular and the triplet one is parallel to the droplet's surface. We have also computed quantum vibrational relaxation rates for both dimers in collision with a single (4)He and we find them to differ by orders of magnitude at the estimated surface temperature. Our results therefore confirm the findings from a great number of experimental data present in the current literature and provide one of the first attempts at giving an accurate, fully quantum picture for the nanoscopic properties of alkali dimers in (4)He clusters.

17.
Minerva Stomatol ; 58(10): 459-70, 2009 Oct.
Article in English, Italian | MEDLINE | ID: mdl-19893471

ABSTRACT

AIM: Fiber-reinforced composite may be successful used to fabricate inlay fixed partial dentures. This study used a finite element model to investigate three-dimensional stress distribution in a 3-unit fiber-reinforced composite fixed partial denture, and compared three types of fiber and three abutment configurations. METHODS: A finite element model of a 3-unit fixed partial denture was used to investigate stress distribution in three different fiber-reinforced composite systems (1) Ribbond Triaxial plus Sinfony; 2) EverStick plus Sinfony; 3) Vectris Pontic/Frame plus Sinfony) and in three different abutment configurations (minimal distal-occlusal and mesial-occlusal preparation; extensive distal-occlusal and mesial-occlusal preparation; mesial-occlusal-distal preparation of both abutment teeth). Maximum load of 196 N was applied at the center of the occlusal and buccal surfaces of the pontic. Stress distribution was calculated in the tooth/restoration complex and in the abutment preparation. RESULTS: When a vertical load was applied, no substantial differences between stress amount in the molar and in the premolar connectors was found. When a lateral load was applied, the stress was greater in the premolar connector than in the molar connector. In all designs investigated, stress was concentrated at the cervical margins of the proximal boxes adjacent to the pontic; no stress concentrated at the occlusal box preparation surface. CONCLUSIONS: Within the limitations of this study, the results suggest that different fiber-reinforced composite systems show similar pattern of stress distribution. Stress concentrates at the connector areas and in the prepared teeth. Peak stress is at the cervical margin of the boxes adjacent to the pontic.


Subject(s)
Dental Abutments , Dental Materials , Dental Restoration, Temporary , Denture, Partial, Fixed , Inlays , Stress, Mechanical , Finite Element Analysis , Humans , Materials Testing
18.
Ann N Y Acad Sci ; 1127: 73-82, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18443333

ABSTRACT

Infertile women are examined to exclude tubal occlusion or a pelvic factor through indirect tests, such as hysterosalpingography (HSG), sonohysterosalpingography/hysterosalpingosonography (SH), and/or laparoscopy (Lps). Assisted reproductive technologies (ART) are proposed to resolve infertility according to the results of the above-mentioned diagnostic procedures. Today, Lps still represents the second option after several failures of in vivo attempts and before moving to conceive in vitro. The aim of this study was to establish the diagnostic power of HSG and SH compared with that of Lps and the efficacy of ART when each single test is used as an inclusion criterion. We recruited 2560 infertile women (aged 20 to 35) to undergo diagnostic and therapeutic procedures to address their infertility in our clinical theatre. Of these, 1080 women underwent Lps and hysteroscopy (Group 1), 525 underwent HSG (Group 2), and 955 underwent SH (Group 3). The positive and negative predictive values of sonosalpingosonography were 75.8% and 91.2% and those of hysterosalpingography were 71.8% and 88.2%, respectively. Endometriosis (stage II-IV of the revised American Society for Reproductive Medicine [ASRM] classification) was diagnosed laparoscopically in 344 out of 1080 women (32%). Only 44 women (13%) with endometriosis showed bilateral tubal occlusion. Pelvic factors other than tubal occlusions are neither diagnosed nor treated in a timely manner by indirect tubal patency tests. The conventional use of HSG and/or SH may increase the time required to find an adequate treatment by which to achieve a successful pregnancy.


Subject(s)
Endometriosis/diagnosis , Gynecology/methods , Hysterosalpingography/methods , Infertility, Female/diagnosis , Infertility, Female/therapy , Laparoscopy/methods , Reproductive Techniques, Assisted , Adult , Endometriosis/complications , Fallopian Tube Diseases/diagnosis , Fallopian Tube Patency Tests , Female , Humans , Hysteroscopy/methods , Predictive Value of Tests , Pregnancy , Sensitivity and Specificity , Sterilization, Tubal
19.
Panminerva Med ; 50(4): 327-37, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19078873

ABSTRACT

A possible relationship between periodontal diseases (PDs) and cardiovascular diseases (CVDs) has been supposed and investigated. This review of the literature focuses exclusively on published studies on current theories and models of correlation between PDs and CVDs. A literature search of clinical and observational studies, in the English language, was performed in MEDLINE/PubMed, OVID database and Cochrane Oral Health Group's Trial Register. In addition, references cited in reviewed studies were evaluated for relevant papers. Various mechanisms are described in order to explain this possible association such as a hyper-responsive inflammatory response to chronic infections in predisposed individuals, and systemic effects of periodontal microorganisms including blood platelet aggregation, atheroma formation, increase in lipid levels, activation of acute phase reaction and systemic production of proinflammatory mediators, but a ultimate relation as well as the potential mechanisms have not been defined yet. Controversial result can be related to different method or objectives of studies including different study design, exposure evaluation, outcome variables and clinical endpoints considered. This paper provides a narrative review of the epidemiological studies dealing with the potential association between PDs and cardiovascular events. A precise association between PDs and CVDs, as well as the involved mechanisms are not yet well defined. Additional large-scale longitudinal epidemiological and intervention studies are necessary to validate this association.


Subject(s)
Cardiovascular Diseases/etiology , Periodontal Diseases/complications , Cardiovascular Diseases/physiopathology , Female , Humans , Inflammation/complications , Inflammation/physiopathology , Male , Models, Biological , Periodontal Diseases/physiopathology , Risk Factors
20.
Appl Opt ; 47(31): 5853-61, 2008 Nov 01.
Article in English | MEDLINE | ID: mdl-19122727

ABSTRACT

We describe a model evaluating changes in the optical isolation of a Faraday isolator when passing from air to vacuum in terms of different thermal effects in the crystal. The changes are particularly significant in the crystal thermal lensing (refraction index and thermal expansion) and in its Verdet constant and can be ascribed to the less efficient convection cooling of the magneto-optic crystal of the Faraday isolator. An isolation decrease by a factor of 10 is experimentally observed in a Faraday isolator that is used in a gravitational wave experiment (Virgo) with a 10 W input laser when going from air to vacuum. A finite element model simulation reproduces with a great accuracy the experimental data measured on Virgo and on a test bench. A first set of measurements of the thermal lensing has been used to characterize the losses of the crystal, which depend on the sample. The isolation factor measured on Virgo confirms the simulation model and the absorption losses of 0.0016 +/- 0.0002/cm for the TGG magneto-optic crystal used in the Faraday isolator.

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