Observation of B_s Production at the Y(5S) Resonance

Using the CLEO detector at the Cornell Electron Storage Ring, we have observed the B_s meson in e^+e^- annihilation at the Υ(5S) resonance. We find 14 candidates consistent with B_s decays into final states with a J/ψ or a D_s^((*)-). The probability that we have observed a background fluctuation is less than 8×10^(-10). We have established that at the energy of the Υ(5S) resonance B_s production proceeds predominantly through the creation of B_s^*B̅ _s^* pairs. We find σ(e^+e^-→B^s^*B̅ ^*)=[0.11_(-0.03)^(+0.04)(stat)±0.02(syst)]  nb, and set the following limits: σ(e^+e^-→B_sB̅ _s)/σ(e^+e^-→B_s^*B̅ _s^*)<0.16 and [σ(e^+e^-→B_sB̅ _s^*)+σ(e^+e^-→B_s*B̅ _s)]/σ(e^+e^-→B_s*B̅ _s^*)<0.16 (90% C.L.). The mass of the B_s^* meson is measured to be M_(B_s^*=[5.414±0.001(stat)±0.003(syst)]  GeV/c^2

A Preliminary Look at the Physics Reach of a Solar Neutrino TPC: Time-Independent Two Neutrino Oscillations

This paper will discuss the physics reach of a solar neutrino TPC containing many tons of He4 under high pressure. Particular attention is given to the LMA and SMA solutions, which are allowed by current data, and which are characterized by a lack of time-dependent phenomena (either summer-winter or day-night asymmetries). In this case, the physics of neutrino masses and mixing is all contained in the energy dependence of the electron neutrino survival probability, (or in its reciprocal, the electron neutrino disappearance probability).Comment: 19 pages, 12 figure

The role of low temperature waste heat recovery in achieving 2050 goals: a policy positioning paper

Urban waste heat recovery, in which low temperature heat from urban sources is recovered for use in a district heat network, has a great deal of potential in helping to achieve 2050 climate goals. For example, heat from data centres, metro systems, public sector buildings and waste water treatment plants could be used to supply 10% of Europe’s heat demand. Despite this, at present, urban waste heat recovery is not widespread and is an immature technology. Based on interviews with urban waste heat stakeholders, investors interested in green investments, and experience from demonstrator projects, a number of recommendations are made. It is suggested that policy raising awareness of waste heat recovery, encouraging investment and creating a legal framework should be implemented. It is also recommended that pilot projects should be promoted to help demonstrate technical and economic feasibility. A pilot credit facility is suggested aimed at bridging the gap between potential investors and heat recovery projects

The Lectin-Gold Technique: An Overview of Applications to Pathological Problems

Lectins are proteins, mainly of vegetal origin, which recognize glycosidic residues with high specificity; for this property they have been used for many studies of molecular biology. The colloidal gold represents at present the most popular electron dense marker employed in immunocytochemistry, since it offers intrinsic and unique characteristics which are superior to those displayed by the other markers. The cytochemical method which utilizes the gold-labelled lectins takes advantages from both the two systems, in order to optimize the localization of the glycoconjugates. The present paper reviews both the technical aspects of the preparation of the lectin-gold complex and its application to some selected pathological problems. In particular, the papers concerning the eye and ear tissues, the urinary, reproductive, nervous and digestive systems and the blood cells are quoted

Scanning Electron Microscopy in the Study of Campylobacter Pylori Associated Gastritis

The close association between Campylobacter pylori (CP), gastritis and peptic ulcer is now well established. Moreover increasing evidence has been collected of a major etiological role of CP in type B chronic gastritis. For this reason, searching for CP is essential in all patients with upper gastrointestinal symptoms. Scanning electron microscopy (SEM) is a most reliable technique for studying the distribution of microorganisms and their relationship to the gastric mucosal surface. The aim of this paper is to compare SEM to other routine methods of detection for CP, such as Giemsa staining on histological sections and Urease Microtiter Test (MT) on fresh tissue and to investigate the surface morphology of gastric mucosa colonized by CP and to correlate it with the histopathological picture. Thirty-seven biopsies taken from the gastric body and the antrum of 22 patients were used for each type of determination. The different parameters were graded semiquantitatively. Histology showed a normal mucosa in 4 cases, chronic superficial gastritis in 12 and chronic atrophic gastritis in 21 cases. SEM was more sensitive than histology and Urease MT in detecting Campylobacter pylori. This is due to the patchy distribution of this bacterium on gastric mucosa. For this reason SEM should always be performed when routine tests are negative. The presence of CP correlated significantly (p \u3c 0.001, Spearman Rank Correlation Test) with the neutrophilic infiltrate, thus with the activity of the gastritis. The CP associated gastritis has no distinctive surface features other than the presence of the bacterium SEM morphology of surface gastric mucous cells suggests that CP does not damage the lining epithelium directly. Neutrophils and inflammatory mediators could be involved in the production of the mucosal lesions

Kinetic Enzymatic Determination of Creatinine by a Rapid Semiautomated Procedure

Peer Reviewe

Characterization of Mucus Glycoconjugates in Normal Human Conjunctiva by Lectins in Light Microscopy, Transmission and Scanning Electron Microscopy

Maintenance of tear film in normal conditions is dependent on 1) mucus layer integrity and 2) the presence and distribution of conjunctival epithelial cell microvilli. In the present work a new methodology has been developed to gain correlative information about microprojection assessment and mucus composition, from the same specimen, by Light Microscopy (LM), Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). We have characterized the glycosidic residues secreted by goblet cells in normal human conjunctiva, by means of four lectins (WGA, ConA, PNA and SBA), conjugated with FITC for LM and with colloidal gold for TEM and SEM. The cytochemical reactions were performed on histological sections of paraffin-embedded material and on semithin and ultrathin sections of both Epon embedded material directly processed for TEM and of blocks recovered from SEM and reprocessed for TEM. WGA, ConA, PNA and SBA receptors were found to be constituents of the mucus produced by goblet cells in human conjunctiva. The granules of the so-called second mucus system (SMS) cells were labelled mainly by WGA. A difference in the quality of glycoconjugates between goblet cells and SMS cells has been also demonstrated. Our results provide an improved method to evaluate alterations of tear film that occur in many conjunctival diseases

Correlative Scanning Electron Microscopy in the Study of Human Gastric Mucosa

We studied two aspects of the human gastric mucosa: - the surface morphology of mucous cells, as viewed by scanning electron microscopy (SEM); - the glycosidic components of intracellular mucins, characterized by means of lectins. The latter were conjugated with fluorescein isothiocyanate and with colloidal gold-silver for the visualization of the reaction products in light microscopy (LM) and in SEM (backscattered mode) respectively. The surface morphology of mucous cells appears to be correlated to the secretory state.In gastric ulcers we found a prevalence of non-secreting cells. A decrease in glycosidic receptors for fucose-binding lectin and galactose-(l-3)-N-acetyl-galactosamine-binding lectin was also observed. This suggests the presence of an impaired mucus secretion which may play a role in the pathogenesis of gastric ulcer. Spiral bacteria, supposed to be aetiologically related to peptic ulcer and gastritis, were easily detected by SEM. Intestinal metaplasia defined complete in LM showed surface morphology and glycosidic components different from those of true intestinal mucosa. This implies the necessity of taking into account also these parameters when classifying this lesion. The same applies to polyps. Our data indicate that correlative SEM may contribute further information on the pathogenesis and pathology of gastric diseases

Neutrinos in a spherical box

In the present paper we study some neutrino properties as they may appear in the low energy neutrinos emitted in triton decay with maximum neutrino energy of 18.6 keV. The technical challenges to this end can be achieved by building a very large TPC capable of detecting low energy recoils, down to a a few tenths of a keV, within the required low background constraints. More specifically We propose the development of a spherical gaseous TPC of about 10-m in radius and a 200 Mcurie triton source in the center of curvature. One can list a number of exciting studies, concerning fundamental physics issues, that could be made using a large volume TPC and low energy antineutrinos: 1) The oscillation length involving the small angle of the neutrino mixing matrix, directly measured in this disappearance experiment, is fully contained inside the detector. Measuring the counting rate of neutrino-electron elastic scattering as a function of the distance of the source will give a precise and unambiguous measurement of the oscillation parameters free of systematic errors. In fact first estimates show that even with a year's data taking a sensitivity of a few percent for the measurement of the above angle will be achieved. 2) The low energy detection threshold offers a unique sensitivity for the neutrino magnetic moment which is about two orders of magnitude beyond the current experimental limit. 3) Scattering at such low neutrino energies has never been studied and any departure from the expected behavior may be an indication of new physics beyond the standard model. In this work we mainly focus on the various theoretical issues involved including a precise determination of the Weinberg angle at very low momentum transfer.Comment: 16 Pages, LaTex, 7 figures, talk given at NANP 2003, Dubna, Russia, June 23, 200

Importance of Tests for the Complete Lorentz Structure of the t --> W+ b vertex at Hadron Colliders

The most general Lorentz-invariant decay-density-matrix for $t\to W^{+}b\to (l^{+}\nu)b$, or for $t\to W^{+}b\to (j_{\bar d}j_u)b$, is expressed in terms of eight helicity parameters. The parameters are physically defined in terms of partial-width-intensities for polarized-final-states in $t\to W^{+}b$ decay. The parameters are the partial width, the $b$ quark's chirality parameter $\xi$, the $W^+$ polarimetry parameter $\sigma$, a "pre-SSB" test parameter $\zeta$, and four $W_{L}$-$W_{T}$ interference parameters $\eta$, $\eta^{'}$, $\omega$, $\omega^{'}$ which test for $\tilde T_{FS}$ violation. They can be used to test for non-CKM-type CP violation, anomalous $\Gamma_{L,T}$'s, top weak magnetism, weak electricity, and second-class currents. By stage-two spin-correlation techniques, percent level statistical uncertainites are typical for measurements at the Tevatron, and several mill level uncertainites are typical at the LHC.Comment: Minor clarifications. Expression for r_{+-} corrected. 19 pages LaTex + Tables + 1 Figur