Search

Continuum and lattice analyses have revealed the existence of a mass-scale in the gluon two-point Schwinger function. It has long been conjectured that this expresses the action of a Schwinger mechanism for gauge boson mass generation in quantum chromodynamics (QCD). For such to be true, it is necessary and sufficient that a dynamically-generated, massless, colour-carrying, scalar gluon+gluon correlation emerge as a feature of the dressed three-gluon vertex. Working with results on elementary Schwinger functions obtained via the numerical simulation of lattice-regularised QCD, we establish with an extremely high level of confidence that just such a feature appears; hence, confirm the conjectured origin of the gluon mass scale., 8 pages, 8 figures

Electrically charged particles can be created by the decay of strong enough electric fields, a phenomenon known as the Schwinger mechanism1. By electromagnetic duality, a sufficiently strong magnetic field would similarly produce magnetic monopoles, if they exist2. Magnetic monopoles are hypothetical fundamental particles that are predicted by several theories beyond the standard model3-7 but have never been experimentally detected. Searching for the existence of magnetic monopoles via the Schwinger mechanism has not yet been attempted, but it is advantageous, owing to the possibility of calculating its rate through semi-classical techniques without perturbation theory, as well as that the production of the magnetic monopoles should be enhanced by their finite size8,9 and strong coupling to photons2,10. Here we present a search for magnetic monopole production by the Schwinger mechanism in Pb-Pb heavy ion collisions at the Large Hadron Collider, producing the strongest known magnetic fields in the current Universe11. It was conducted by the MoEDAL experiment, whose trapping detectors were exposed to 0.235 per nanobarn, or approximately 1.8 × 109, of Pb-Pb collisions with 5.02-teraelectronvolt center-of-mass energy per collision in November 2018. A superconducting quantum interference device (SQUID) magnetometer scanned the trapping detectors of MoEDAL for the presence of magnetic charge, which would induce a persistent current in the SQUID. Magnetic monopoles with integer Dirac charges of 1, 2 and 3 and masses up to 75 gigaelectronvolts per speed of light squared were excluded by the analysis at the 95% confidence level. This provides a lower mass limit for finite-size magnetic monopoles from a collider search and greatly extends previous mass bounds.

We present novel results for the three-gluon vertex, obtained from an extensive quenched lattice simulation in the Landau gauge. The simulation evaluates the transversely projected vertex, spanned on a special tensorial basis, whose form factors are naturally parametrized in terms of individually Bose-symmetric variables. Quite interestingly, when evaluated in these kinematics, the corresponding form factors depend almost exclusively on a single kinematic variable, formed by the sum of the squares of the three incoming four-momenta, $q$, $r$, and $p$. Thus, all configurations lying on a given plane in the coordinate system $(q^2, r^2, p^2)$ share, to a high degree of accuracy, the same form factors, a property that we denominate \emph{planar degeneracy}. We have confirmed the validity of this property through an exhaustive study of the set of configurations satisfying the condition $q^2 = r^2$, within the range $[0, 5\, \rm GeV]$. Moreover, a preliminary exploration reveals that the planar degeneracy persist in the case of more arbitrary configurations. This drastic simplification allows for a remarkably compact description of the main bulk of the data, which is particularly suitable for future numerical applications. A semi-perturbative analysis reproduces the lattice findings rather accurately, once the inclusion of a gluon mass has cured all spurious divergences., Comment: 8 pages, 7 figures

We are grateful for constructive comments from K.-L. Cai, O. Denisov, F. de Soto, T. Frederico, J. Friedrich, C. Mezrag, V. Mokeev, W.-D. Nowak, C. Quintans, G. Salme and J. Segovia. Work supported by: National Natural Science Foundation of China (Grant nos. 12135007, 11805097); Helmholtz-Zentrum Dresden-Rossendorf High Potential Programme; Spanish Ministry of Science and Innovation (MICINN) (Grant nos. PID2020-113334GB, PID2019-107844GBC22); Generalitat Valenciana (Grant no. Prometeo/2019/087); Junta de Andalucia (Grant nos. P18-FR-5057, UHU-1264517, UHU EPIT2021); and STRONG-2020 "The strong interaction at the frontier of knowledge: fundamental research and applications" which received funding from the European Union's Horizon 2020 research and innovation programme (grant no. 824093)., Analyses of the pion valence-quark distribution function (DF), u(pi) (x; sigma), which explicitly incorporate the behaviour of the pion wave function prescribed by quantum chromodynamics (QCD), predict u(pi) (x similar or equal to 1; sigma) similar to (1 - x)(beta(sigma)), beta(sigma greater than or similar to m(p)) > 2, where mp is the proton mass. Nevertheless, more than forty years after the first experiment to collect data suitable for extracting the x similar or equal to 1 behaviour of up, the empirical status remains uncertain because some methods used to fit existing data return a result for up that violates this constraint. Such disagreement entails one of the following conclusions: the analysis concerned is incomplete; not all data being considered are a true expression of qualities intrinsic to the pion; or QCD, as it is currently understood, is not the theory of strong interactions. New, precise data are necessary before a final conclusion is possible. In developing these positions, we exploit a single proposition, viz. there is an effective charge which defines an evolution scheme for parton DFs that is all-orders exact. This proposition has numerous corollaries, which can be used to test the character of any DF, whether fitted or calculated., National Natural Science Foundation of China (NSFC) 12135007 11805097, Spanish Government European Commission PID2020-113334GB PID2019-107844GBC22, Generalitat Valenciana European Commission, General Electric Prometeo/2019/087, Junta de Andalucia P18-FR-5057 UHU-1264517 UHU EPIT2021, STRONG-2020 "The strong interaction at the frontier of knowledge: fundamental research and applications" - European Union's Horizon 2020 research and innovation programme 824093, Helmholtz-Zentrum Dresden-Rossendorf High Potential Programme

An outstanding goal of physics is to find solutions that describe hadrons in the theory of strong interactions, Quantum Chromodynamics (QCD). For this goal, the light-front Hamiltonian formulation of QCD (LFQCD) is a complementary approach to the well-established lattice gauge method. LFQCD offers access to the hadrons' nonperturbative quark and gluon amplitudes, which are directly testable in experiments at existing and future facilities. We present an overview of the promises and challenges of LFQCD in the context of unsolved issues in QCD that require broadened and accelerated investigation. We identify specific goals of this approach and address its quantifiable uncertainties.

Zusammenfassung Die Haufigkeit von Dermatophyten im gesunden Fell oder im Fell nicht pilzbedingter Hauterkrankungen — trockenes Ekzem, Alopezie nach der Geburt, Kala-Azar, usw. — wurde bei 100 Katzen und 300 Hunden ermittelt. Bei 17 (17 %) Katzen und 18 (6 %) Hunden wurden Dermatophyten nachgewiesen. Aus den Untersuchungsmaterialien der Katzen wurde nur der Dermatophyt Microsporum canis gezuchtet. Aus den Proben von den Hunden wurden neben Microsporum canis — (14mal), Microsporum gypseum — (2mal) und Trichophyton mentagrophytes-Stamme (2mal) isoliert. Summary The prevalence of dermatophytes was determined in the healthy skin or in dermatological skin lesions which were not caused by fungi-dry eczema, alopecia after delivery, kala-azar etc. —of 100 cats and 300 dogs. In 17 (17 %) cats and 18 (6 %) dogs dermatophytes were found. From the samples of the cats only the dermatophyte Microsporum canis was cultured. From the samples of the dogs strains of Microsporum canis (14), of Microsporum gypseum (2) and of Trichophyton mentagrophytes (2) were isolated.

We study a fundamental, all order cancellation operating between graphs of distinct kinematic nature, which allows for the construction of gauge-independent effective self-energies, vertices, and boxes at arbitrary order., Comment: 4 pages, 3 figures. Contributed to QCD 03: High-Energy Physics International Conference in Quantum Chromodynamics, Montpellier, France, 2-9 July 2003

The molecular structure and vibrational spectra of the different oxidation states of tetrakis(dimethylamino)ethylene (TDAE) are calculated using structural optimization and normal-mode calculations. The predictions are compared with x-ray structural data and infrared spectra of TDAE, TDAE-C60 and (TDAE)(Cl)2. The C–N stretch vibration frequency and axial torsional angle are shown to be sensitive indicators of the charge state of the molecule. TDAE+, which occurs in TDAE-C60 is found to have a near-degenerate configurational ground state.

The accurate execution of DNA replication requires a strict control of the replication licensing factors hCdt1 and hCdc6. The role of these key replication molecules in carcinogenesis has not been clarified. To examine how early during cancer development deregulation of these factors occurs, we investigated their status in epithelial lesions covering progressive stages of hyperplasia, dysplasia, and full malignancy, mostly from the same patients. Abnormal accumulation of both proteins occurred early from the stage of dysplasia. A frequent cause of unregulated hCdc6 and hCdt1 expression was gene amplification, suggesting that these components can play a role per se in cancer development. Overexpression of hCdt1 and hCdc6 promoted rereplication and generated a DNA damage response, which activated the antitumor barriers of senescence and apoptosis. Generating an inducible hCdt1 cellular system, we observed that continuous stimulus by deregulated hCdt1 led to abrogation of the antitumor barriers and resulted in the selection of clones with more aggressive properties. In addition, stable expression of hCdc6 and hCdt1 in premalignant papilloma cells led to transformation of the cells that produced tumors upon injection into nude mice depicting the oncogenic potential of their deregulation. ©2007 American Association for Cancer Research.

Using the pinch technique, we show how to construct the QCD effective charge to all orders., Comment: 4 pages, no figures. Contributed to QCD 02: High-Energy Physics International Conference in Quantum Chromodynamics, Montpellier, France, 2-9 July 2002

Objectives: to assess the incidence and the rate of progression of internal carotid artery (ICA) stenosis and to determine the related risk factors. Design: open prospective study. Materials and methods: between 1988-1947, 442 carotid al arteries with various degrees of stenosis were followed using colour duplex ultrasonography every 6 months. Of these arteries, 290 (66%) were asymptomatic, 62 (14%) had caused transient ischaemic attack and 90 (20%) a stroke. In 145 eases (33%), there was concomitant coronary artery disease (CAD), in 134 (30%) diabetes mellitus, in 248 (56%) hypertension, in 139 (31%) hypercholesterolaemia and in 370 (84%) history of smoking. Of the plaques, 44 (10%) were uniformly echolucent, 19 (4%) haemorrhagic, 136 (31%) predominantly echolucent, 146 (33%) predominantly echogenic and 97 (22%) uniformly echogenic. Results: significant progression of stenosis occurred in 82 cases (19%). The mean progression rate in these cases was 15% annually (range: 5-50%). There uns no statistically significant correlation between the progression of the ICA stenosis and initial neurological status, age, gender, diabetes mellitus, hypertension, hypercholesterolaemia and smoking habit. Stenosis progression was correlated only with CAD and the ultrasonographic characteristics of the plaques. Patients with CAD as well as those with uniformly echolucent plaques presented a higher incidence and rate of stenosis progression (p

In quantum electrodynamics with fermions f = e,\mu..., knowledge of the vacuum polarization spectral function determined from the tree level e^+e^- -> f^+f^- cross sections, together with a single low energy measurement of the fine structure constant \alpha, enables the construction of the one-loop effective charge \alpha_eff(q^2) for all q^2. It is shown how an identical procedure can be followed in the electroweak sector of the Standard Model to construct three gauge-, scale- and scheme-independent one-loop electroweak effective charges and an effective weak mixing angle from the tree level e^+e^- -> W^+W^-, ZH and e^+\nu_e -> W^+Z, W^+\gamma, W^+H differential cross sections, together with three low energy measurements, which may be chosen to be \alpha and the masses of the W and Z bosons. It is found that the corresponding proper self-energy-like functions thus constructed are identical to those obtained in the pinch technique framework. In this way, it is shown how the concept of effective charges in the electroweak Standard Model is as well-defined and unique as in quantum electrodynamics., Comment: 40 pages, 7 figs, Latex, uses epsf.sty, axodraw.sty (included), fig 6 scale corrected

The adherence of strains of Candida albicans to buccal epithelial cells as well as the phagocytosis of these organisms by human polymorphonuclear leucocytes (PMNL) was studied. The strains of C. albicans were obtained from patients' urine. from bird faeces and from soil. The strains of C. albicans obtained from patients and the environment displayed greater adhering ability (23.8 +/- 6.4 and 27.5 +/- 5.2 respectively) than the avian strains (14.4 +/- 2.2) (P0.01). Strains obtained from the environment were resistant to phagocytosis (81.6 +/- 0.2 organisms ingested per 200 PMNL) and killing (8.4 +/- 2.6%) by PMNL as compared to human and avian strains (P0.01). These observations indicate that environmental strains of C. albicans may be more virulent for human beings.

We tested peripheral blood from 60 patients with definite multiple sclerosis (MS) and 60 healthy controls for polymorphonuclear leukocyte (PMNL) functions and found significant disorders in adherence (9.07% +/- 8.18% for patients versus 28.97% +/- 5.76% for controls), chemotaxis (18.32 +/- 3.1 for patients versus 30.49 +/- 4.52 for controls), phagocytosis (73.6 +/- 25.25 for patients versus 111.2 +/- 25.7 for controls), and bactericidal action (10.35% +/- 5% for patients versus 25.09% +/- 4.82% for controls). All differences were significant (p0.001). We confirmed the results by retesting 3 to 8 months later. The depressed PMNL functions in MS patients may explain their increased susceptibility to infections of the respiratory, digestive, and urinary tracts.

Patients with malignancies are at high risk to develop infections byCandida albicans. We have compared the adherence ofC. albicans isolated from urine cultures to bladder epithelial cells obtained from healthy volunteers and patients with cancer of the bladder. The mean number ofC. albicans adhering per epithelial cell from areas infiltrated from cancer was significantly higher as compared to cells obtained from intact areas of cancerous bladders bladders and from normal bladders. The increased adherence ofC. albicans to cancerous epithelial cell suggests that malignancies are associated with alterations of the epithelial cell surface which render the cells more susceptible to colonization byC. albicans. The increased colonization may predispose these patients toC. albicans infections.

Ciprofloxacin was administered to 10 healthy volunteers at a dose of 250 mg orally. Serum and polymorphonuclear leukocytes (PMNLs) were obtained from all subjects before the administration of the drug and 12 hours after the administration. In addition serum was obtained from all subjects at 24 and 48 hours after ciprofloxacin administration. All sera and PMNLs were used for the chemotactic, phagocytic and killing determinations of the PMNLs. The results demonstrated that serum obtained 12 hours after the administration of ciprofloxacin potentiates PMNL chemotactic activity (chemotactic index (CI) = 33.0 +/- 4.2 microns (means +/- S.D.)) as compared to the chemotactic activity generated by serum obtained prior to administration of the drug, CI = 20.4 +/- 4.4 microns (p < 0.01). Serum obtained 24 and 48 hours after ciprofloxacin administration did not stimulate PMNL function. The administration of ciprofloxacin did not have any direct influence on the PMNLs in terms of their chemotactic response. Furthermore, serum obtained after the administration of ciprofloxacin markedly enhanced PMNL phagocytosis and killing of all organisms tested. Ciprofloxacin also acted directly on the PMNLs and increased their bactericidal activity. These results demonstrate that ciprofloxacin potentiates PMNL function in vivo which may be of potential clinical benefit.

The antimicrobial efficacy of preservatives in ophthalmic solutions was tested. Five strains were used as challenge organisms. They represented bacteria, yeasts and molds. Sixty per cent of the ophthalmic solutions showed a good preservation against S. aureus ATCC 6538, according to the standards and in 40% of cases, the bacteria disappeared on the second week. Against E. coli ATCC 8739, 90% of the samples were well preserved and in 10% the bacteria disappeared by the second week. Against Ps. aeruginosa ATCC 9027, C. Albicans ATCC 10231 and Asp. niger ATCC 16404, the ophthalmic solutions showed a 100% preservation. The majority of the products showed a satisfactory preservation. They contained declared preservatives and sometimes combinations of two antimicrobial agents.

The survival of bacteriophage 1 of the Salmonella typhimurium phage typing scheme was studied in four different types of sterile soil at 4.20 and 37 degrees C. The longevity of the phage was generally short, not exceeding 36 days and depended on the temperature and the type of soil.

Culturing Escherichia coli, Proteus mirabilis and Klebsiella pneumoniae in the presence of subinhibitory concentrations (1/4 MIC) of trimethoprim, sulphamethoxazole or their combination, resulted in reduced adherence of all the above strains. The number of phagocytosed bacteria pre-exposed to subinhibitory concentrations of the above antibiotics was not significantly changed, but a significant increase of bactericidal activity of the polymorphonuclear leucocytes was observed. Furthermore, filtrates of K. pneumoniae and P. mirabilis grown in the presence of trimethoprim alone or in combination with sulphamethoxazole induced an increased chemotactic response of human polymorphonuclear leucocytes.

Summary The ability of human polymorphonuclear leucocytes (PMNs) to ingest and kill gentamicin-sensitive and resistant Pseudomonas aeruginosa strains was studied. Strains becoming resistant to gentamicin either by laboratory training or through an R-factor were more susceptible to the phagocytic and bactericidal function of the PMNs. These results may explain previous clinical and laboratory observations indicating that gentamicin-resistant strains are less virulent.

Faeces from 10 colon cancer patients and from 10 control subjects were studied by quantitative and qualitative aerobic and anaerobic techniques using a variety of non selective, selective and differential media. In several cases, there were significantly different numbers of organisms of specific types recovered from the two groups studied. Most prominent and meaningful findings were the higher frequency of isolation and counts of Bacteroides species (especially B. fragilis group) and of C. paraputrificum in the patient group. Apart from the demonstration of the altered faecal bacterial flora in colon cancer patients and of the possible etiologic role of C. paraputrificum and B. fragilis in colon carcinogenesis, the bacteriological data, confirmed by more extensive studies, could be used as an index for colon cancer or for populations at high risk.

The in vitro antibacterial activity of HR-756 was compared to cefoxitin and cefuroxime. 122 multiresistant clinical isolates including Enterobacteriaceae (104) an

Ninety-eight hospital strains of Pseudomonas aeruginosa isolated from six different hospitals in Athens were serotyped by a slide agglutination test with unabsorbed commercial antisera. Serotypes O6, O11, O12, and "pool E" strains (strains that agglutinated only in pool E, which contained antisera against O2, O5, O15, and O16 antigens, but did not agglutinate in the individual antisera) predominated, accounting for more than 62% of all isolates tested. In respect to serotypes, (i) there was no apparent correlation with hospital of origin, (ii) most strains of serotypes O6 and O11 were sensitive to gentamicin and carbenicillin (iii) most strains of pool E were from urine and were resistant to these drugs, (iv) all 9 strains of serotype O12 tested were resistant to carbenicillin and all 5 strains tested hydrolyzed this drug, and (v) 24 of 25 strains of pool E were resistant to carbenicillin but only 2 of 17 strains hydrolyzed it.

Summary. A thin-layer chromatographic technique for the estimation of lipase in Pseudomonas aeruginosa and staphylococci is described. The technique needs a short incubation period (4 h), while the subsequent procedure is quite simple and rapid. The validity of the technique was established by testing 56 strains of Ps. aeruginosa and 35 strains of staphylococci. The results strongly support the usefulness of the technique which can be quite easily applied to routine use.

Netilmicin was compared with sisomicin, tobramycin and amikacin against 65 recent clinical enterobacterial isolates found to be highly resistant to gentamicin (MIC ≥ 80 μg/ml). Netilmicin showed a hig

Fecal cholesterol and its metabolites were measured in 10 patients with colon cancer and 10 control subjects. All individuals were consuming a mixed western diet of collection of stool specimens. The fecal concentration of total neutral sterols and coprostanol was greater in the control subjects as compared to the colon cancer patients, but the difference was not statistically significant. The same was the case for the metabolic conversion rate of cholesterol. The frequency distribution of the latter was bimodal especially among control subjects, with 3 subjects having an extremely high conversion rate. The level of neutral sterols is lower from stated values in most reports for colon cancer patients but higher to that reported for high risk populations for colon cancer and to this respect our finding are relevant with the increasing incidence of colon cancer in Greece.

Two kits containing fluorescein labeled-polyvalent antisera to Bacteroides fragilis, Bacteroides distasonis, Bacteroides ovatus, Bacteroides thetaiotaomicron, Bacteroides vulgatus (Fluoretec-F) and to Bacteroides melaninogenicus subsp. melaninogenicus and intermedins and to Bacteroides asaccharolyticus (non-oral strains) (Fluoretec-M) were evaluated for the identification of the respective organisms in bacterial cultures and clinical specimens. In both cases immunofluorescent tests were compared to the bacteriological data. The results clearly demonstrated that Fluoretec-F has a specificity 97% and a sensitivity 96%. The corresponding values for Fluoretec-M were 99% and 87.5% respectively, either clinical specimens or pure cultures were examined. The presence of aerobic of facultative anaerobic bacteria and obligate anaerobic bacteria other than those to which antisera were included in the test kits did not seem to influence the test result. No cross-reactivity between Fluoretec-F and -M were observed. Also, no positive fluorescence was obtained when other anaerobic bacteria than Bacteroides spp . were tested. The same was also the case with various aerobic or facultative anaerobic bacteria. The use of Fluoretec-F and -M is considered as a useful tool for the early accurate identification of the Bacteroides species mentioned, which may serve as a guide for an appropriate prompt therapy which is especially needed in serious anaerobic infections.

One hundred and six clinical isolates of Pseudomonas aeruginosa, collected from various hospitals were typed with O-antisera and studied for their susceptibility to antibiotics and phages. Forty-four of 49 multiresistant isolates belonged to the O12 serogroup, a serogroup rarely found among strains of other resistance phenotypes. Eleven of the 45, O12 isolates were resistant to all phages, and 31 were sensitive only to phage 68. The latter pattern was encountered in nine of the 61 strains comprising the other O-serogroups.

Aldosterone injected i.m. decreased the release of renomedullary PGEs and the index (urinary Na/K ratio) in conscious normotensive intact and adrenalectomized rats. Coadministration of spironolactone increased the release of PGEs as well as the index (urinary Na/K ratio). The effect of spironolactone was partly inhibited by aspirin injected in a ratio 5:1 (aspirin:spironolactone), and effect which could be reversed by the infusion of a synthetic prostaglandin (PGA2) in a subhypotensive dose.