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Poultry processing establishments use antimicrobial aids on broiler parts to minimize Campylobacter contamination. A silver-stabilized hydrogen peroxide (SHP) product was assessed for use as an antimicrobial processing aid. In a series of experiments, wing segments with skin were inoculated with 103 to 107 cells of Campylobacter coli, followed by treatment with SHP at 15,000 or 30,000 mg/L, peroxyacetic acid (PAA) at 300 or 3,000 mg/L (parts per million), or water. Each treatment was applied by either dip or spray. Rinsates from each wing segment were analyzed for direct counts and prevalence of Campylobacter. Treatment with SHP or PAA significantly reduced Campylobacter levels compared with water controls by up to 2.22 log CFU/mL. At high inoculum levels (106 to 107), SHP and PAA applied by dip had up to 1.27 log CFU/mL further reductions of Campylobacter levels compared with spray-treated wing segments. Additionally, wing drumettes were observed to retain higher levels and prevalence of Campylobacter recovery compared with wing flats at a low inoculation level (103). The results indicated that there was no carryover effect of SHP (same day versus 24 h) and dip treatment with SHP or PAA decreased Campylobacter recovery on broiler chicken wing segments compared with a water control. Although a 2-log reduction was modest, SHP had similar efficacy as the commonly used processing aid PAA. SHP shows potential for further investigation as an antimicrobial processing aid for use on poultry parts. HIGHLIGHTS

The nature and role of the binary companion of carbon-oxygen white dwarf stars that explode as Type Ia supernovae (SNe Ia) are not yet fully understood. Past detections of circumstellar material (CSM) that contain hydrogen for a small number of SN Ia progenitor systems suggest that at least some have a nondegenerate companion. In order to constrain the prevalence, location, and quantity of CSM in SN Ia systems, we performed a near-ultraviolet (NUV) survey with the Hubble Space Telescope (HST) to look for the high-energy signature of SN Ia ejecta interacting with CSM. Our survey revealed that SN 2015cp, a SN 1991T-like overluminous SN Ia, was experiencing late-onset interaction between its ejecta and surrounding CSM at $664$ days after its light-curve peak. We present ground- and space-based follow-up observations of SN 2015cp that reveal optical emission lines of H and Ca, typical signatures of ejecta-CSM interaction. We show how SN 2015cp was likely similar to the well-studied SN Ia-CSM event PTF11kx, making it the second case in which an unambiguously classified SN Ia was observed to interact with a distant shell of CSM that contains hydrogen ($R_{\rm CSM} \gtrsim 10^{16}\ {\rm cm}$). The remainder of our HST NUV images of SNe Ia were nondetections that we use to constrain the occurrence rate of observable late-onset CSM interaction. We apply theoretical models for the emission from ejecta-CSM interaction to our NUV nondetections, and place upper limits on the mass and radial extent of CSM in SN Ia progenitor systems., 29 pages, 10 figures, 6 tables; accepted to ApJ

Objective: To identify and document the incidence of severe, clinically symptomatic stenosis in a general intensive care unit (ICU) population and thus to identify airway interventions that are associated with stenosis. Design: A prospective, observational study over five years. Setting: Clinical investigation in a district general hospital adult intensive care unit. Subjects: One hundred and thirty-six consecutive, intubated patients with an ICU stay of five or more days and who survived to be followed up to six months were studied. Interventions: None. Measurements and main results: Detailed information was recorded for every patient on the type of intubation, number of reintubations and mode of ventilation. Post-discharge patients were clinically examined and had full pulmonary function tests, with flow loops, performed at two and six months post-ICU discharge. Of the 136 patients, 48 had open operative tracheostomies performed and 37 patients were reintubated twice or more; 120 had pulmonary function ...

Alterations in intestinal permeability reflect one component of intestinal epithelial barrier function. The objective of this study was to assess the degree of derangement of intestinal permeability in critically ill patients and to investigate the relationship of this to markers of disease severity and sepsis. Sixteen patients admitted to the intensive care unit for a variety of problems were studied with the severity of illness and degree of sepsis recorded daily. A differential sugar absorption test, using lactulose and mannitol as markers, was performed, and in 10 patients this was repeated after an interval of between 4-11 days. The use of the lactulose/mannitol (L/M) ratio corrects for variables unrelated to permeability such as gastric emptying. The L/M ratio was significantly higher in patients (median 0.98) compared to normal controls (median 0.008). The ratios showed no relation to disease severity or sepsis. These results establish that increased intestinal permeability occurs in the general ICU patient but that it is not uniquely related to sepsis. The extent of this abnormality suggests that further study is required to show the various influences on this process.

Thirty-seven patients with a wide range of illnesses were studied during mechanical ventilation of the lungs in an intensive care unit. Fifteen were sedated with a continuous propofol infusion, with analgesia provided by bolus doses of papaveretum. Twelve received a continuous infusion of papaveretum, supplemented by bolus doses of midazolam. The level of sedation was assessed every four hours and measurements were made of haemodynamic and respiratory variables. Levels of sedation were generally satisfactory in both groups. Six patients who received propofol required the use of muscle relaxants, because of their strong respiratory drives, to achieve synchronisation with the ventilator. There was no significant difference in respiratory or haemodynamic variables between the groups, but several patients required inotropic support because of their disease. There was no evidence of inhibition of adrenal steroidogenesis in the propofol group. Propofol can be a useful sedative agent in the intensive care unit, but sedative regimens should be tailored to individual patient requirements.

The development of damage in cross-ply Hercules AS4/3502 graphite/epoxy laminates has been investigated. Specific endeavors were to identify the mechanisms for initiation and growth of matrix cracks and to determine the effect of matrix cracking on the stiffness loss in cross-ply laminates. Two types of matrix cracks were identified. These include both straight and curved cracks. The experimental study of matrix crack damage revealed that the curved cracks formed after the straight cracks and followed a repeatable pattern of location and orientation relative to the straight cracks. Therefore, it was postulated that the growth mechanism for curved cracks is driven by the stress state resulting from the formation of the straight cracks. This phenomenon was analytically investigated by a finite-element model of straight cracks in a cross-ply laminate. The finite-element results provide supporting evidence for the postulated growth mechanism. The experimental study also revealed that the number of curved cracks increased with the number of consecutive 90-deg plies. Finally, experimental results show as much as 10-percent degradation in axial stiffness due to matrix cracking in cross-ply graphite/epoxy laminates.

Summary The haemodynamic response to tracheal intubation was compared in 303 patients in whom anaesthesia was induced with either thiopentone 4 mg/kg, etomidate 0.3 mg/kg or propofol 2.5 mg/kg, with and without fentanyl 2 μg/kg. There was after propofol alone a significant decrease in arterial blood pressure, which did not increase above control values after intubation. Significant increases in arterial pressure followed intubation in patients induced with thiopentone or etomidate alone. Increases in heart rate occurred with all agents after laryngoscopy. The use of fentanyl resulted in arterial pressures lower than those after the induction agent alone, and in an attentuation, but not abolition of the responses to largyngoscopy and intubation.

Continuous fiber laminated composites are known to undergo substantial load induced damage in the form of matrix cracking, interior delamination, fiber fracture, etc. These damage modes produce significant losses in component performance measures such as stiffness, residual strength, and life. The authors have previously constructed a general model for predicting the response of laminated composites with damage. The current paper utilizes the model to predict stiffness loss as a function of damage in quasi-isotropic and angle-ply laminates with matrix cracks. It is shown that the model is capable of predicting the stiffness loss for any layup by utilizing the same input data, thus producing a model which is independent of stacking sequence. The favorable comparisons of the model to experimental results reported herein support the validity of the model.

GnRH interacts with a plasma membrane receptor to provoke gonadotropin release, as well as regulate numbers of its own receptor and target cell responsiveness. Receptor numbers are altered in different physiological states of the animal. Microaggregation of the GnRH receptor mimics all known actions of the releasing hormone, and therefore is viewed as an early step in the molecular mechanism of hormone action. Internalized hormone is neither necessary nor sufficient for stimulation of known releasing hormone actions. Evidence summarized in the present work suggests that Ca2+ serves a role as a second messenger for GnRH-stimulated gonadotropin release, and that it may be involved in receptor up-regulation in response to the releasing hormone. In the former role, diacylglycerols by their action on protein kinase C, in a fashion independent of the Ca2+ -calmodulin system, may act as a signal amplifier.

This report summarizes research completed during a four year period under AFOSR grant no. AFOSR-84-0067 and originally detailed under Texas A&M research Foundation proposal no. RF-84-34 and dated October 1983. The objective of this research has been to develop an accurate damage model for predicting strength and stiffness of continuous fiber laminated composite media subjected to fatigue or monotonic loading and to verify this model with experimental results obtained from composite specimens of selected geometry and makeup. Further details of this research can be found in the three previous annual reports available either from AFOSR or the author. Keywords: Composites, Damage, Experimental mechanics, Continuum mechanics, Internal state variables, Laminated composites.

The airway pressures at ventilatory frequencies of 15, 60, 100, 120 and 150 breaths per minute were measured in eight adult patients undergoing coronary artery bypass grafting. Measurements were made perioperatively at four stages: precardiopulmonary bypass with the chest closed, precardiopulmonary bypass with the chest open, postcardiopulmonary bypass with the chest open and postcardiopulmonary bypass with the chest closed. In five patients thoracic compliance and airways resistance were also measured at these times. Neither sternotomy nor cardiopulmonary bypass made any significant difference to the airway pressures during normal and high frequency ventilation, nor were lung mechanics affected.

The maximal calcium-activated isometric tension produced by a skinned frog single muscle fiber falls off as the ionic strength of the solution bathing this fiber is elevated declining to zero near 0.5 M as the ionic strength is varied using KCl. When other neutral salts are used, the tension always declines at high ionic strength, but there is some difference between the various neutral salts used. The anions and cations can be ordered in terms of their ability to inhibit the maximal calcium-activated tension. The order of increasing inhibition of tension (decreasing tension) at high ionic strength for anions is propionate- ≃ SO4-- < Cl- < Br-. The order of increasing inhibition of calcium-activated tension for cations is K+ ≃ Na+ ≃ TMA+ < TEA+ < TPrA+ < TBuA+. The decline of maximal calcium-activated isometric tension with elevated salt concentration (ionic strength) can quantitatively explain the decline of isometric tetanic tension of a frog muscle fiber bathed in a hypertonic solution if one assumes that the internal ionic strength of a muscle fiber in normal Ringer's solution is 0.14–0.17 M. There is an increase in the base-line tension of a skinned muscle fiber bathed in a relaxing solution (no added calcium and 3 mM EGTA) of low ionic strength. This tension, which has no correlate in the intact fiber in hypotonic solutions, appears to be a noncalcium-activated tension and correlates more with a declining ionic strength than with small changes in [MgATP], [Mg], pH buffer, or [EGTA]. It is dependent upon the specific neutral salts used with cations being ordered in increasing inhibition of this noncalcium-activated tension (decreasing tension) as TPrA+ < TMA+ < K+ ≃ Na+. Measurements of potentials inside these skinned muscle fibers bathed in relaxing solutions produced occasional small positive values (

History. —W. F. N., male child, aged 2, up to Dec. 23, 1909, had had no serious illness. About 3 a. m., December 23, the child awoke and seemed to be in great pain. Half an ounce of castor-oil was given by the parents. About 5 a. m. the child began vomiting. Pain and vomiting continuing, a physician was called about noon. He prescribed calomel and more castoroil, but everything given by mouth was rejected. On the second day several enemas were given, and, excepting a very small stool following the first enema, neither feces nor flatus passed. There had been no mucus nor blood passed per rectum. Pain, vomiting and absolute constipation had been continuous from the beginning of the illness. I was called on the evening of the fourth day and found that the child had died a few minutes before my arrival. I asked for an autopsy and