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We report the first measurement of the (e,e^{'}p) three-body breakup reaction cross sections in helium-3 (^{3}He) and tritium (^{3}H) at large momentum transfer [⟨Q^{2}⟩≈1.9  (GeV/c)^{2}] and x_{B}>1 kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta 40≤p_{miss}≤500  MeV/c that, in the QE limit with no rescattering, equals the initial momentum of the probed nucleon. The measured cross sections are compared with state-of-the-art ab initio calculations. Overall good agreement, within ±20%, is observed between data and calculations for the full p_{miss} range for ^{3}H and for 100≤p_{miss}≤350  MeV/c for ^{3}He. Including the effects of rescattering of the outgoing nucleon improves agreement with the data at p_{miss}>250  MeV/c and suggests contributions from charge-exchange (SCX) rescattering. The isoscalar sum of ^{3}He plus ^{3}H, which is largely insensitive to SCX, is described by calculations to within the accuracy of the data over the entire p_{miss} range. This validates current models of the ground state of the three-nucleon system up to very high initial nucleon momenta of 500  MeV/c.

We report the first measurement of the (e,e^{'}p) three-body breakup reaction cross sections in helium-3 (^{3}He) and tritium (^{3}H) at large momentum transfer [⟨Q^{2}⟩≈1.9  (GeV/c)^{2}] and x_{B}>1 kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta 40≤p_{miss}≤500  MeV/c that, in the QE limit with no rescattering, equals the initial momentum of the probed nucleon. The measured cross sections are compared with state-of-the-art ab initio calculations. Overall good agreement, within ±20%, is observed between data and calculations for the full p_{miss} range for ^{3}H and for 100≤p_{miss}≤350  MeV/c for ^{3}He. Including the effects of rescattering of the outgoing nucleon improves agreement with the data at p_{miss}>250  MeV/c and suggests contributions from charge-exchange (SCX) rescattering. The isoscalar sum of ^{3}He plus ^{3}H, which is largely insensitive to SCX, is described by calculations to within the accuracy of the data over the entire p_{miss} range. This validates current models of the ground state of the three-nucleon system up to very high initial nucleon momenta of 500  MeV/c.

We report the first measurement of the (e,e′p) reaction cross-section ratios for Helium-3 (He3), Tritium (H3), and Deuterium (d). The measurement covered a missing momentum range of 40≤pmiss≤550MeV/c, at large momentum transfer (〈Q2〉≈1.9 (GeV/c)2) and xB>1, which minimized contributions from non quasi-elastic (QE) reaction mechanisms. The data is compared with plane-wave impulse approximation (PWIA) calculations using realistic spectral functions and momentum distributions. The measured and PWIA-calculated cross-section ratios for He3/d and H3/d extend to just above the typical nucleon Fermi-momentum (kF≈250 MeV/c) and differ from each other by ∼20%, while for He3/H3 they agree within the measurement accuracy of about 3%. At momenta above kF, the measured He3/H3 ratios differ from the calculation by 20%−50%. Final state interaction (FSI) calculations using the generalized Eikonal Approximation indicate that FSI should change the He3/H3 cross-section ratio for this measurement by less than 5%. If these calculations are correct, then the differences at large missing momenta between the He3/H3 experimental and calculated ratios could be due to the underlying NN interaction, and thus could provide new constraints on the previously loosely-constrained short-distance parts of the NN interaction.

We report the first measurement of the (e,e′p) reaction cross-section ratios for Helium-3 (He3), Tritium (H3), and Deuterium (d). The measurement covered a missing momentum range of 40≤pmiss≤550MeV/c, at large momentum transfer (〈Q2〉≈1.9 (GeV/c)2) and xB>1, which minimized contributions from non quasi-elastic (QE) reaction mechanisms. The data is compared with plane-wave impulse approximation (PWIA) calculations using realistic spectral functions and momentum distributions. The measured and PWIA-calculated cross-section ratios for He3/d and H3/d extend to just above the typical nucleon Fermi-momentum (kF≈250 MeV/c) and differ from each other by ∼20%, while for He3/H3 they agree within the measurement accuracy of about 3%. At momenta above kF, the measured He3/H3 ratios differ from the calculation by 20%−50%. Final state interaction (FSI) calculations using the generalized Eikonal Approximation indicate that FSI should change the He3/H3 cross-section ratio for this measurement by less than 5%. If these calculations are correct, then the differences at large missing momenta between the He3/H3 experimental and calculated ratios could be due to the underlying NN interaction, and thus could provide new constraints on the previously loosely-constrained short-distance parts of the NN interaction.

The first measurements of the three-body phototdisintegration of 3He polarized parallel and anti-parallel to a circularly polarized γ-ray beam were carried out at the High Intensity γ-ray Source (HIγS) facility located at Triangle Universities Nuclear Laboratory (TUNL). A high pressure 3He target, polarized via spin-exchange optical pumping with alkali metals, was used in the experiments. The neutrons from the three-body photodisintegration were detected with sixteen 12.7 cm diameter liquid scintillator detectors. The spin-dependent cross sections and the contributions from the three-body photodisintegration to the 3He Gerasimov-Drell-Hearn sum rule integrand were extracted and compared with state-of-the-art three-body calculations at the incident photon energies of 12.8, 14.7, and 16.5 MeV. The calculations, which include the Coulomb interaction are in good agreement with the results of the measurements at 12.8 and 14.7 MeV but deviate from the results at 16.5 MeV.

Various theories predict the possible existence of T-odd and P-odd shortrange forces between spin ½ fermions, proportional to S・r where S is the fermion spin and r is the separation between particles. We use ensembles of polarized nuclei and an un-polarized mass to search for such a force over sub-mm ranges. We established an improved upper bound on the product gsgpn of the scalar coupling to particles in the un-polarized mass and the pseudo-scalar coupling of polarized neutrons for force ranges from 10−4 to 10−2 m, corresponding to a mass range of 2・10−3 to 2・10−5 eV for the exchange boson [1].

The first measurement of the three-body photodisintegration of polarized ³He using a circularly polarized photon beam has been performed at incident energies of 12.8 and 14.7 MeV. This measurement was carried out at the high-intensity γ-ray source located at Triangle Universities Nuclear Laboratory. A high-pressure ³He target, polarized via spin exchange optical pumping with alkali metals, was used in the experiment. The spin-dependent double- and single-differential cross sections from ³He(γ,n)pp for laboratory angles varying from 30° to 165° are presented and compared with state-of-the-art three-body calculations. The data reveal the importance of including the Coulomb interaction between protons in the three-body calculations. [ABSTRACT FROM AUTHOR]

The first measurement of the three-body photodisintegration of longitudinally polarized ³He with a circularly polarized γ-ray beam was carried out at the High Intensity γ-ray Source facility located at Triangle Universities Nuclear Laboratory. The spin-dependent double-differential cross sections and the contributions from the three-body photodisintegration to the ³He Gerasimov-Drell-Hearn integrand are presented and compared with state-of-the-art three-body calculations at the incident photon energies of 12.8 and 14.7 MeV. The data reveal the importance of including the Coulomb interaction between protons in three-body calculations. [ABSTRACT FROM AUTHOR]

Following the first experiment on three-body photodisintegration of polarized 3He utilizing circularly polarized photons from High-Intensity Gamma Source (HI $ \gamma$ S) at Duke Free Electron Laser Laboratory (DFELL), a new high-pressure polarized 3He target cell made of pyrex glass coated with a thin layer of sol-gel doped with aluminum nitrate nonahydrate has been built in order to reduce the photon beam-induced background. The target is based on the technique of spin exchange optical pumping of hybrid rubidium and potassium and the highest polarization achieved is ∼ 62% determined from both NMR-AFP and EPR polarimetries. The phenomenological parameter that reflects the additional unknown spin relaxation processes, X , is estimated to be ∼ 0.10 and the performance of the target is in good agreement with theoretical predictions. We also present beam test results from this new target cell and the comparison with the GE180 3He target cell used previously at HI $ \gamma$ S. This is the first time that the sol-gel coating technique has been used in a polarized 3He target for nuclear-physics experiments. [ABSTRACT FROM AUTHOR]

Early detection and treatment improve the prognosis for oral cancer. Delays from the onset of symptoms to clinical diagnosis are common. Our aim is to identify factors associated with this delay. Between 1995 and 1998, we interviewed 105 consecutive patients with histologically confirmed oral cancer in Greece. If 21 or more days elapsed from the time the patient noticed major symptoms to a definitive diagnosis, we called it a delay (52% of cases). We used logistic and linear regression to estimate odds ratios of delayed diagnosis and to identify correlates of length of delay, respectively. Former smokers had a 4.3 times greater risk of delayed diagnosis compared with current smokers (95% confidence interval: 1.1-17.1). The length of delay was greater among single patients, nonsmokers, or those with stage IV tumors. Clinicians should be advised that delay in the diagnosis of oral cancer occurs frequently, even in individuals who do not smoke heavily. [ABSTRACT FROM AUTHOR]

Twenty-seven patients (19 females and 8 males) with a clinically diagnosed desquamative gingivitis were used in this study. Twenty-seven additional patients with oral and skin diseases and with gingival involvement other than that of the desquamative gingivitis type served as controls. Biopsy gingival specimens were sectioned and stained with H and E. The rest of the tissue specimen was cut with a cryostat and used for immunofluorescent assays of the tissue-bound antibodies (IgG, IgA, lgM, C3 and fibrin). Circulating antibodies were determined by using the indirect immunofluorcscence method in serum samples. Normal human oral mucosa and several animal epithelial tissues were used as substrates. The immunopathologic findings suggest the diagnosis of lichen planus in the presence of linear or granular fibrin deposition at the basement membrane zone/mucosal submucosal interface with or without cytoid bodies and cicatricial pemphigoid, in the presence of circulating and/or tissue-bound immunoglobulins and C3 in a linear continuous pattern along the BMZ. It is suggested that an accurate diagnosis of the underlying disease of the desquamative gingivitis can be made on the basis of the clinical, histopathologic, immunopathologic and follow-up findings. [ABSTRACT FROM AUTHOR]

Examines a design method for low-cost totally self-checking checkers for 1-out-of-n and (n-1)-out-of-n codes. Complexity and sophistication of digital systems and their important applications; Monitoring of the outputs of a functional circuit.

Two families of Greek origin with oral pemphigus vulgaris are reported. Both are fully documented cases of familial pemphigus in Greek Mediterranean patients. In the first family, a sister and a brother developed oral mucosal pemphigus lesions within a 5-year period, and a cousin had died from the disease 20 years earlier. In the second family, a daughter, a son and their mother developed the disease 2, 4 and 6 years apart. HLA typing has been performed and disclosed striking associations and similarities between the members of each family. Review of the fully documented cases of familial pemphigus vulgaris is also presented in a tabular form. [ABSTRACT FROM AUTHOR]

Solid phase extraction (SPE) methods are studied for the sample pretreatment for HPLC analysis of Taxus cell suspension cultures. Various types of SPE materials were tested for the extraction of both the taxane standards and samples of various origin. Comparison between the different cartridges and the different elution solvents are made in terms of extraction recovery and sample clean-up. Selective elution of the taxanes is achieved by a gradient elution scheme. [ABSTRACT FROM AUTHOR]

One hundred and sixty HIV-infected Greek patients were prospectively examined and the oral signs and symptoms were recorded. At the time of oral examina tion, 76 patients were asymptomatic seropositive, 47 were in ARC stage and 37 had AIDS. One or more oral findings were recorded in 90.6% of the patients while a total of 33 different lesions were observed. The more common oral lesions (highly suspicious) were candidiasis (61%), hairy leukoplakia (24%), periodontitis (19%), necrotizing gingivitis (11%) and Kaposi's sarcoma (12%). In addition some unclassified lesions or symptoms (xerostomia 26%, burning mouth syndrome 19%, patchy depapillated tongue 16%, hairy tongue 10%, exfoliative cheilitis 4%), were common while submandibular and cervical lymph node enlargement were found in 49% of the patients. Interestingly in 16 patients (10%) the suspicion of HIV infection was exclusively based on oral lesions. Our findings show that oral signs and symptoms are common and some times early manifestations of HIV infection and it is in association to those reported in previous studies. [ABSTRACT FROM AUTHOR]

Glycogen storage disease type 1b is a rare metabolic disorder which affects the transport system of glucose-6-phosphatase metabolism. As a result, hepatomegaly, failure to thrive, renal dysfunction and recurrent infections occur in affected patients. In this paper, the oral complications in three children with glycogen storage disease type 1b are discussed. Oral ulcers were a common finding, probably due to severe neutropenia and impaired neutrophil migration which characterises the onset of this rare disorder. [ABSTRACT FROM AUTHOR]

Orogenital sex in the last decades has become a common sexual practice (fellatio and cunnilingus) between both heterosexual and homosexual individuals. Consequently, several sexually transmitted diseases (STDs) including bacterial infections, are a persistent problem in Europe and throughout the world, despite vigorous efforts in prevention and people education. The last two decades, HIV infection, revived the interest of the medical community and the people for the sexually transmitted diseases. Many of these bacterial infections present predominantly with characteristic oral signs and symptoms. As a result, it is imperative for the oral physician (stomatologist) to keep abreast of the latest updates in the behavior and to be aware of the whole spectrum of clinical manifestations of these diseases. Orogenital bacterial infections may be divided into two major categories: (i) Common including syphilis and gonorrhoea and (ii) Rare, including chlamydia trachomatis infection and tropical sexually transmitted infections (chancroid, donovanosis, lymphogranuloma venereum). Syphilis is the leader of sexually transmitted diseases and has been of great interest in the past and today and has played a central role in medicine for several decades. The oral lesions of syphilis (primary secondary and tertiary stages) have a broad spectrum of manifestations, which mimic a lot of other oral lesions. The recent incidence data, the oral manifestations, the laboratory tests and treatment of both categories of these diseases will be discussed, as the increased practice of oral sex has become a more important potential route of transmission for oral and genital bacterial pathogens. Stomatologists and Dentists, frequently evaluate oral mucosal manifestations and thus play an important role in the diagnosis and treatment of many of highly infectious sexually transmitted infections. [ABSTRACT FROM AUTHOR]

Editorial. Provides information on how to treat oral leukoplakia. Definition of the clinical term leukoplakia; Three major forms of leukoplakia; Factors for the development of oral leukoplakia; Information on the malignant transformation of leukoplakic lesions; Parameters to be considered in the treatment protocol of oral leukoplakia.

Abstract: The differential cross section of the 10B(p,α)7Be reaction has been measured for bombarding proton energies between 2.1MeV and 6.0MeV, in 100keV steps, at seven laboratory angles from 30° to 150°. This reaction is of importance because it can be a source of radioactive waste in reactors which will use boron as a nuclear fuel. The total cross section was extracted at each proton energy. On average, the results of this experiment are ∼16% higher than previously reported measurements. The astrophysical S-factors were also extracted from the total cross sections. [Copyright &y& Elsevier]

We measured the triple coincidence A(e,e^{'}np) and A(e,e^{'}pp) reactions on carbon, aluminum, iron, and lead targets at Q^{2}>1.5  (GeV/c)^{2}, x_{B}>1.1 and missing momentum >400  MeV/c. This was the first direct measurement of both proton-proton (pp) and neutron-proton (np) short-range correlated (SRC) pair knockout from heavy asymmetric nuclei. For all measured nuclei, the average proton-proton (pp) to neutron-proton (np) reduced cross-section ratio is about 6%, in agreement with previous indirect measurements. Correcting for single-charge exchange effects decreased the SRC pairs ratio to ∼3%, which is lower than previous results. Comparisons to theoretical generalized contact formalism (GCF) cross-section calculations show good agreement using both phenomenological and chiral nucleon-nucleon potentials, favoring a lower pp to np pair ratio. The ability of the GCF calculation to describe the experimental data using either phenomenological or chiral potentials suggests possible reduction of scale and scheme dependence in cross-section ratios. Our results also support the high-resolution description of high-momentum states being predominantly due to nucleons in SRC pairs.

Oral medicine (stomatology) is a recognized and increasingly important dental specialty in many parts of the world that recognizes and fosters the interplay between medical health and oral health. Its dental activities rely greatly on the underlying biology of disease and evidence-based outcomes. However, full recognition of the importance of oral medicine to patient care, research, and education is not yet totally universally acknowledged. To address these shortcomings, we outline the birth, growth, and future of oral medicine globally, and record identifiable past contributions to the development of the specialty, providing an accurate, unique, and valuable resource on oral medicine. Although it was challenging to gather the data, we present this information as a review that endeavors to summarize the salient points about oral medicine, based on MEDLINE, other internet searches, communication with oral medicine and stomatological societies across the world, the web page http://en.wikipedia.org/wiki/List_of_dental_organizations, and discussions with a wide range of key senior persons in the specialty., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Carcinoma of the oral cavity is one of the most common cancers worldwide. Tobacco smoking and the consumption of alcoholic beverages are significant risk factors but to the authors' knowledge the role of nutrition is not adequately understood. The authors undertook an epidemiologic study of oral carcinoma occurring in Greece, where tobacco smoking and alcohol consumption are common but the incidence of the disease is among the lowest reported in Europe., Methods: One hundred six patients with histologically confirmed incident oral carcinoma and an equal number of control subjects matched for age and gender were studied. Dietary information was assessed through a validated extensive food frequency questionnaire and the data were analyzed using conditional logistic regression., Results: After adjustment for energy intake, tobacco smoking, and alcohol consumption, there was evidence that the consumption of cereals, fruits, dairy products, and added lipids (which in Greece are represented mostly by olive oil) was found to be associated inversely with the risk of oral carcinoma. Only with respect to meat and meat products was there adequate evidence of a positive association with the risk of oral carcinoma. Among the micronutrients studied, riboflavin, magnesium, and iron appeared to be correlated inversely with the disease., Conclusions: Fruits, cereals, dairy products, and olive oil appear to convey protection against oral carcinoma and their effects may be mediated through higher intakes of riboflavin, iron, and magnesium. The low incidence of oral carcinoma reported in Greece may be explained in part by the higher consumption of the food groups and micronutrients that appear to protect against the disease., (Copyright 2002 American Cancer Society.)

We investigated effects on oral cancer (OC) risk of an interaction between a single nucleotide polymorphism (SNP) in the alcohol dehydrogenase 3 (ADH3) gene and alcohol consumption levels using a hospital-based study of 93 cases and 99 controls conducted in Athens, Greece. This SNP affects ethanol metabolism in vitro and appeared to interact with alcohol consumption in a previous OC study. We also evaluated a SNP in CYP2E1, another gene involved in ethanol metabolism, reported to be associated with OC risk in a European population. Data on genotypes and risk factors obtained from interviews were analyzed using multivariate logistic regression, accounting for potential confounders. No overall (marginal) association was found between OC risk and ADH3 genotypes. An interaction between ADH3 genotypes and alcohol consumption levels, however, was suggested. In non-drinkers, the ADH3(1-1) genotype has higher risk than ADH3(1-2) or ADH3(2-2) genotypes, but for subjects consuming alcohol, lower risk was observed for ADH3. We fit a logistic regression model to estimate the increase in OC risk associated with each alcohol drink consumed per week. We estimated that OC risk increased by 31.5% per drink/week for the ADH3(2-2) genotype, 4.1% for the ADH3(1-2) genotype and 1.6% for the ADH3(1-1) genotype. Evidence of genotype-environment interaction was suggestive (p = 0.048, Wald chi p = 0.145, likelihood ratio). This finding is opposite to that reported for a population in Puerto Rico, where the ADH3(1-1) genotype seemed more sensitive to ethanol exposure. In Greece, genetic variation at the CYP2E1 SNP is almost entirely absent, with only 1 case and 1 control heterozygous for the variant. By contrast, in a population in France where an OC association was reported, the frequency of CYP2E1 heterozygotes was 5% in controls and 9% in OC cases. These findings illustrate the importance of replicating SNP associations both within and between different racial and ethnic groups and geographic regions., (Published 2001 Wiley-Liss, Inc.)

Studies on the involvement of the human papillomavirus (HPV) in initiation and progression of oral neoplasia have generated conflicting results. The observed discrepancy is attributable mainly to the varying sensitivity of the applied methodologies and to epidemiologic factors of the examined patient groups. To evaluate the role of HPV in oral carcinogenesis, we analyzed 53 potentially neoplastic and neoplastic oral lesions consisting of 29 cases of hyperplasia, 5 cases of dysplasia, and 19 cases of squamous cell carcinomas, as well as 16 oral specimens derived from healthy individuals. A highly sensitive nested polymerase chain reaction (PCR) assay was used, along with type-specific PCR, restriction fragment length polymorphism analysis, dot blotting, and nonisotopic in situ hybridization. Nested PCR revealed the presence of HPV DNA in 48 of the 53 (91%) pathologic samples analyzed, whereas none (0%) of the normal specimens was found to be infected. Positivity for HPV was independent of histology and the smoking habits of the analyzed group of patients. At least one "high risk" type, such as HPV 16, 18, and 33, was detected by type-specific PCR in 47 (98%) infected specimens, whereas only 1 (2%) squamous cell carcinoma was solely infected by a "low risk" type (HPV 6). HPV 16 was the prevailing viral type, being present in 71% of infected cases. Single HPV 16 and HPV 18 infections were confirmed by restriction fragment length polymorphism. HPV 58 was detected by dot blotting in three hyperplastic lesions. HPV positivity and genotyping were further confirmed, and the physical status of this virus was evaluated by nonisotopic in situ hybridization. Diffuse and punctate signals, indicative of the episomal and integrative pattern of HPV infection, were observed for low- and high-risk types, respectively. Our findings are suggestive of an early involvement of high-risk HPV types in oral carcinogenesis.