Effect of surface properties of different food contact materials on the efficiency of quaternary ammonium compounds residue recovery and persistence

Residues of quaternary ammonium compounds (QACs) remaining after sanitising were evaluated for a number of materials used in food plants. The residues were collected by swabs and measured using a spectrophotometric method. Surface topography and energy affected the QACs recovery. Highest percentage of QACs recovery was achieved for the tile material (102.2%) which had the most hydrophilic properties and least irregularities in surface topology, followed by stainless steel (82.1%). Meanwhile, the lowest recovery occurred in PVC (42.1%) and resin (44.3%) that exhibited hydrophobic characteristics and abrupt changes in height profile in a given surface area. Monitoring of QACs residues deposited on the surfaces after 7 days showed that the recovery of QACs in PVC and resin reduced significantly (P < 0.05), supposing that QACs might be degraded or interacted with the materials. However, no significant changes in residue recovery were observed for tiles and stainless steel surfaces after 7 days.     

Ultimate Response of RC Beams Strengthened with CFRP Plates

Poststrengthening and retrofitting is a growing reality, as existing structures are required to meet the demands of modern society. Apart from the need to increase load capacity, upgrading of a structure may be necessitated through deterioration of the structure by corrosion or accidental damage, a change in the structural system, or to rectify initial design and construction faults. A commonly observed mode of failure for beams strengthened using carbon-fiber-reinforced polymer composite material plates is one due to the plate peeling off prematurely and unpredictably at relatively low magnitudes of applied loading. End plate anchorages and long unanchored plate lengths, which can add significantly to the overall cost of a strengthening solution, overcome this problem. This paper presents the results of flexural tests on ten reinforced concrete beams strengthened with different plate configurations. A strain compatibility and force equilibrium method of analysis, coupled with an empirical rule derived from the test data, is demonstrated to be effective in predicting the ultimate response of simply supported beams in bending with and without end plate anchorages and irrespective of plate length.     

Topography of wound canals and possibilities of collateral blood circulation

By complexed structural and functional study performed in 76 dogs in acute, subacute and chronic experiments, destruction of muscles of the extremity, intraorganic vascular bed of which does not participate in collateral blood circulation was shown not to be an impairing factor in vascular trauma. If the wound canal localization directly relates to the topography of most important collaterals pronounced structural and functional disorders of ischemic genesis develop in the organism and in the extremity within the next day. In case of primary adhesion of the soft tissue wound in the zone of collateral pathways or distinctly limited foci of purulent wound infection in any topography of wound canal acute arterial insufficiency is compensated due to mobilization of all vascular reserves. These are primarily arteries of remaining muscles and nerves, cutaneofascial vessels and arterial bed of the opposite extremity as well. On contrary, wound suppuration sharply suppresses vessel plastic properties, promotes tissue necrosis, including ischemic gangrene of the extremity distant segments. Basic dogma of anatomic experimental studies were supported by clinico-physiological evaluation of collateral circulation in the 16 wounded with vascular disturbances.     

Clinic characteristics associated with reduced hospitalization of drug users with AIDS

The purpose of this study was to develop a substantive grounded theory of courage among middle-aged adults with long-term health concerns. Twenty-five persons from rural and non-metropolitan areas of Central Illinois were selected to participate in this study based on theoretical sampling procedures. Interviews of 1 to 2 hours using openended questions were audiotaped and transcribed verbatim. The data were analysed using grounded theory methods. Courage among middle-aged adults with long-term health concerns was determined to consist of an ongoing progressive-regressive process of becoming and being courageous. Being courageous involves being fully aware of and accepting the threat of a long-term health concern, solving problems using discernment, and developing enhanced sensitivities to personal needs and the world in general. Courageous behaviour consists of taking responsibility and being productive. Courage is not limitless, and the process of becoming and being courageous is dependent on intrapersonal and interpersonal factors. Health-care providers facilitate this process by demonstrating competence and communicating effectively. Outcomes of being courageous include personal integrity and thriving in the midst of normality.     

Diagnosis of natural rubber latex allergy: multicenter latex skin testing efficacy study. Multicenter Latex Skin Testing Study Task Force

BACKGROUND: No characterized diagnostic natural rubber latex skin testing material is licensed for use in the United States. OBJECTIVE: We have conducted a multicenter clinical skin testing study to document the safety and diagnostic sensitivity and specificity of a candidate Hevea brasiliensis nonammoniated latex (NAL) extract. These data are intended to support the licensing of this reagent for the diagnosis of latex allergy in high-risk populations. METHODS: Three hundred twenty-four subjects (304 adults and 20 children) were classified by their clinical history as having latex allergy (LA group, 124 adults and 10 children) or having no latex allergy (NLA group, 180 adults and 10 children). All subjects provided blood samples and then received sequential puncture skin tests (PSTs) at 1, 100, or 1000 microg/mL protein with a bifurcated needle and NAL (Greer Laboratories) from Malaysian Hevea brasiliensis (clone 600) sap. A 2-stage glove provocation test was used to clarify latex allergy status of individuals with positive history/negative PST result and negative history/positive PST result mismatches. RESULTS: Twenty-four subjects (15%) originally designated as having LA on the basis of their initial clinical history were reclassified to the NLA group on the basis of a negative glove provocation test result. Of the 134 subjects with LA, 54 (40%) were highly sensitive to latex, with a positive PST result at 1 microg/mL NAL. The Greer NAL reagent produced a positive PST rate (sensitivity) of 95% and 99% in subjects with LA at 100 microg/mL and 1 mg/mL, respectively. The negative PST rate (specificity) in 190 subjects with a negative history with the NAL extract at 100 microg/mL and 1 mg/mL, was 100% and 96%, respectively. Immediately after the PST, mild systemic reactions (mainly pruritus) were recorded in 16.1 % of the adults in the LA group and 4.4% of the adults in the NLA group. No reactions required treatment with epinephrine. Only mild delayed reactions were observed in 9.6% (LA group) and 2.8% (NLA group) of subjects 24 to 48 hours after PST. Mean wheal and erythema diameters measured in the 10 children in the LA group with spina bifida at 100 microg/mL and 1 mg/mL were similar to those observed in the adults in the LA group, suggesting that children are not at increased risk for systemic reactions compared with adults. CONCLUSIONS: A suggestive clinical history is necessary but not sufficient for a definitive diagnosis of IgE-dependent latex allergy. These data support the safety and diagnostic efficacy of the Greer NAL, skin test reagent at 100 micro/mL and 1 mg/mL for confirmatory PSTs.