bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiargument logical operations performed with excitable chemical medium
Authors: Gorecka J. , Gorecki J.
Published: February 2006

Assuming that a pulse of excitation corresponds to the logical “true” state one can use a chemical medium for information processing and construct devices that execute the basic binary logical operations. Here we discuss direct chemical realizations of four argument logical functions equivalent to special types of McCulloch-Pitts neuron. We demonstrate that if a proper geometrical arrangement of excitable and nonexcitable areas is used then the construction of the considered devices can be much simpler than in the case where they are composed of chemical binary logical gates.
Path-integral virial estimator for reaction-rate calculation based on the quantum instanton approximation
Authors: Yang Sandy , Yamamoto Takeshi , Miller William H.
Published: February 2006

The quantum instanton approximation is a type of quantum transition-state theory that calculates the chemical reaction rate using the reactive flux correlation function and its low-order derivatives at time zero. Here we present several path-integral estimators for the latter quantities, which characterize the initial decay profile of the flux correlation function. As with the internal energy or heat-capacity calculation, different estimators yield different variances (and therefore different convergence properties) in a Monte Carlo calculation. Here we obtain a virial (-type) estimator by using a coordinate scaling procedure rather than integration by parts, which allows more computational benefits. We also consider two different methods for treating the flux operator, i.e., local-path and global-path approaches, in which the latter achieves a smaller variance at the cost of using second-order potential derivatives. Numerical tests are performed for a one-dimensional Eckart barrier and a model proton transfer reaction in a polar solvent, which illustrates the reduced variance of the virial estimator over the corresponding thermodynamic estimator.
Thermochemistry of the activation of N2 on iron cluster cations: Guided ion beam studies of the reactions of Fen+ (n=1–19) with N2
Authors: Tan Lin , Liu Fuyi , Armentrout P. B.
Published: February 2006

The kinetic energy dependences of the reactions of Fen+ (n=1–19) with N2 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0–15eV. In addition to collision-induced dissociation forming Fem+ ions, which dominate the product spectra, a variety of FemN2+ and FemN+ product ions, where m⩽n, is observed. All processes are observed to exhibit thresholds. Fem+–N and Fem+–2N bond energies as a function of cluster size are derived from the threshold analysis of the kinetic energy dependences of the endothermic reactions. The trends in this thermochemistry are compared to the isoelectronic D0(Fen+–CH), and to bulk phase values. A fairly uniform barrier of 0.48±0.03eV at 0K is observed for formation of the FenN2+ product ions (n=12, 15–19) and can be related to the rate-limiting step in the Haber process for catalytic ammonia production.
Stabilization of the filamentation instability and the anisotropy of the background plasma
Authors: Bret A. , Deutsch C.
Published: February 2006

The interaction of a relativistic electron beam with an anisotropic Maxwellian plasma is investigated, with a focus on the stabilization condition for the filamentation instability. It is found that this condition is very sensitive to the anisotropy degree of the background plasma so that the investigation of the beam instability may not be easily decoupled from the state of the background plasma in typical fusion conditions. Furthermore, regardless of the plasma isotropy, filamentation can no longer be suppressed when the beam density exceeds a threshold value that is determined.
Parallel electron velocity shear instability in a magnetized plasma
Authors: Eliasson B. , Shukla P. K. , Hall J. O.
Published: February 2006

It is shown that the parallel electron velocity shear can destabilize low-frequency (in comparison with the electron gyrofrequency) electrostatic waves in a magnetized plasma. A new dispersion relation is derived and solved for the parameters relevant for laboratory experiments of velocity shear instabilities in a magnetized plasma.
Suppression of phase separation in Hf-silicate films using NH3 annealing treatment
Authors: Chung K. B. , Whang C. N. , Cho M.-H. , Yim C. J. , Ko D.-H.
Published: February 2006

The structural characteristics of Hf-silicate films and nitrogen incorporated Hf-silicate films, prepared using a NH3 annealing treatment, were investigated by various measurements. Hf-silicate films annealed in a N2 ambient at 900°C show the evidence of crystallization in local regions, resulting in the phase separation of HfO2 and SiO2. In addition, a SiO2 overlayer is formed on the Hf-silicate films, due to the diffusion of Si by postannealing in an ambient of N2 at 900°C. However, in nitrogen incorporated Hf-silicate films, prepared using a NH3 annealing treatment, phase separation is effectively suppressed and no SiO2 overlayer is present. The incorporated N is distributed into the film and interfacial layer, and obstructs the diffusion of Si from the substrate as well as the film. Structural changes in films affect electrical characteristics such as the dielectric constant and flatband voltage.
Detection of magnetic state in a nanoscale ferromagnetic ring by using ballistic semiconductor two-dimensional electron gas
Authors: Hara Masahiro , Shibata Junya , Kimura Takashi , Otani Yoshichika
Published: February 2006

We have developed a method of measuring magnetization process in a ferromagnetic ring by analyzing a characteristic response of a semiconductor two-dimensional electron gas (2DEG) lying beneath the ring. A 2DEG microcross structure is formed underneath a ferromagnetic ring to detect the position of paired domain walls of the onion state. The variation of the bend resistance due to the rotation of the paired domain walls is quantitatively reproduced by a semiclassical billiard model.
Low-threshold lasers based on a high-mobility semiconducting polymer
Authors: Heliotis G. , Choulis S. A. , Itskos G. , Xia R. , Murray R. , Stavrinou P. N. , Bradley D. D. C.
Published: February 2006

Progress toward electrically driven conjugated polymer lasers should benefit from the identification of materials that exhibit good charge transport properties coupled with large optical gain. Here, we report a detailed study of a blue-emitting fluorene-based polymer that combines a large hole mobility with desirable stimulated emission characteristics. Laser oscillation is achieved within distributed feedback structures and leads to low threshold, tunable lasers operating in the blue spectral region. Our results establish this material as an attractive gain medium with which to try and construct a polymer laser diode.
High-temperature operation of self-assembled GaInNAs∕GaAsN quantum-dot lasers grown by solid-source molecular-beam epitaxy
Authors: Liu C. Y. , Yoon S. F. , Sun Z. Z. , Yew K. C.
Published: February 2006

Self-assembled GaInNAs∕GaAsN single layer quantum-dot (QD) lasers grown using solid-source molecular-beam epitaxy have been fabricated and characterized. Temperature-dependent measurements have been carried out on the GaInNAs QD lasers. The lowest obtained threshold current density in this work is ∼1.05kA∕cm2 from a GaInNAs QD laser (50×1700μm2) at 10°C. High-temperature operation up to 65°C was also demonstrated from an unbonded GaInNAs QD laser (50×1060μm2), with high characteristic temperature of 79.4K in the temperature range of 10–60°C.
Laser-nanostructured Ag films as substrates for surface-enhanced Raman spectroscopy
Authors: Henley S. J. , Carey J. D. , Silva S. R. P.
Published: February 2006

Pulsed-laser (248nm) irradiation of Ag thin films was employed to produce nanostructured Ag∕SiO2 substrates. By tailoring the laser fluence, it was possible to controllably adjust the mean diameter of the resultant near-spherical Ag droplets. Thin films of tetrahedral amorphous carbon (ta-C) were subsequently deposited onto the nanostructured substrates. Visible Raman measurements were performed on the ta-C films, where it was observed that the intensity of the Raman signal was increased by nearly two orders of magnitude, when compared with ta-C films grown on nonstructured substrates. The use of laser annealing as a method of preparing substrates, at low macroscopic temperatures, for surface-enhanced Raman spectroscopy on subnanometer-thick films is discussed.
Conclusiveness of the Cochrane Neonatal Reviews: A systematic analysis
Authors: Mandel Dror , Littner Yoav , Mimouni Francis B. , Lubetzky Ronit
Published: February 2006

Abstracts

Aim: To assess the conclusiveness of the Cochrane Neonatal Reviews (CNRs). We tested the hypotheses that: 1) the majority of the reviews is inconclusive; 2) the majority of reviews recognizes the need for further studies; 3) the ability to reach a conclusion is dependent upon both the number of studies and the number of patients. We also aimed to determine whether the conclusiveness of the CNRs was affected by time.

Methods: We selected CNRs available in the Cochrane Library in June 2004. The number of randomized clinical trials (RCTs) found, number of RCTs included for analysis, number of patients enrolled, the stated need for further studies, and the conclusiveness of CNRs were recorded.

Results: Out of 170 CNRs, 67.7% were conclusive. The average number of articles was similar, but the total number of patients enrolled was three times higher in the conclusive CNRs. The percentage of articles included in conclusive studies was significantly higher than in inconclusive ones. The vast majority of CNRs recognized the need for further studies. The number of studies included correlated significantly with the total number of patients included. The percentage of conclusive CNRs correlated negatively with year of publication.

Conclusion: The majority of CNRs is conclusive, but emphasizes the need for further studies. The ability of a CNR to reach a conclusion is affected by the cumulative sample size and by the number of studies performed. The probability of a newer review to be conclusive is lower than that of an older review.
Studies of the Toxicological Potential of Tripeptides (L-Valyl-L-prolyl-L-proline and L-lsoleucyl-L-prolyl-L-proline): II. Introduction
Authors: Bernard Bruce K. , Nakamura Yasunori , Bando Izuki , Mennear John H.
Published: February 2006

The consumption of fermented milk to maintain good health, including the maintance of normal blood pressure, is an ancient tradition in a number of areas of the world (e.g., East Asia, France). Recent studies have suggested that fermented milk has a normotensive effect in hypertensive rats and humans, but no effect on blood pressure in normotensive rats and humans. Two tripeptides, L-valyl-L-prolyl-L-proline (VPP) and L-isoleucyl-L-prolyl-L-proline (IPP), have been identified as possessing significant angiotensin-converting enzyme inhibitory activity and are therefore believed to be the source of the normotensive effects. This document, the second of nine chapters, provides information on these two tripeptides, including physical/chemical properties, molecular weights, chemical structures, normal consumption in the diet, manufacturing information, regulatory approval in Japan, and Japanese consumption of food containing enhanced levels of VPP plus IPP. In addition, the results of studies in rats and humans conducted to evaluate the effect of these substances on blood pressure are presented. The research suggests that in adult normotensive volunteers, consumption of up to 7.92 mg of VPP and 4.52 mg IPP daily for 2 weeks causes neither clinical signs nor biologically meaningful effects on systolic or diastolic blood pressure, pulse rate, or clinical pathology (serum chemistry or hematology). However, when a similar study was performed using mildly and moderately hypertensive adults as subjects and they consumed 2.52 mg of VPP and 1.64 mg of IPP per day, a significant drop in systolic blood pressure was detected for a prolonged time interval. This chapter also introduces the issue of safety testing for these substances and describes the information to be found in the subsequent seven chapters.
Studies of the Toxicological Potential of Tripeptides (L-Valyl-L-prolyl-L-proline and L-lsoleucyl-L-prolyl-L-proline): VIII. Assessment of Cytotoxicity and Clastogenicity of Tripeptides-Containing Casein Hydrolysate and Lactobacillus helveticus-fermented Milk Powders in Chinese Hamster Lung Cells
Authors: Maeno Masafumi , Mizuno Seiichi , Mennear John H. , Bernard Bruce K.
Published: February 2006

The objective of this chromosomal aberration test was to assess the mutagenic potential of tripeptides by determining their ability to induce chromosomal aberrations in cultured Chinese hamster lung (CHL) cells. The test agents used in these experiments were (1) powdered casein hydrolysate (CH) and (2) powdered Lactobacillus helveticus-fermented milk (FM). Both test agents contain two tripeptides, L-valyl-L-prolyl-L-proline (VPP) and L-isoleucyl-L-prolyl-L-proline (IPP). CHL cells were cultured and exposed in the presence or absence of a rat hepatic metabolizing system (S9); CH or FM (1250, 2500, 5000 /μg/ml of incubation medium); or positive-control agents, mitomycin C (0.1 or 0.05 /ig/ml) or benzo(a)pyrene (20 /μg/ml). In experiments with CH, cells were incubated for 6 h (either in the presence or absence of S9) or for 24 h (without S9). In experiments with FM, the cells were incubated for 6 h (either in the presence or absence of S9) or for 24 or 48 h (without S9). Neither short-term nor continuous exposure to either CH or FM caused the induction of significant changes in cell growth indices, incidences of chromosomal aberrations or the incidence of polyploids. Exposures of cells to mitomycin C and benzo(a)pyrene consistently resulted in the induction of the anticipated aberrant cells after either short-term or continuous exposures. The results of these assays support the conclusions that, under the conditions of these experiments, neither CH nor FM possesses demonstrable potential for the induction of cytotoxicity or clastogenesis.
Global Geography of ‘Little Italy’: Italian Neighbourhoods in Comparative Perspective
Authors: Gabaccia Donna R.
Published: February 2006

Between 1870 and 1970 the migration of 26 million people from Italy produced an uneven geography of Little Italies worldwide. Migrants initially clustered residentially in many lands, and their festivals, businesses, monuments and practices of everyday life also attracted negative commentary everywhere. But neighbourhoods labelled as Little Italies came to exist almost exclusively in North America and Australia. Comparison of Italy's migrants in the three most important former ‘settler colonies’ of the British Empire (the USA, Canada, Australia) to other world regions suggests why this was the case. Little Italies were, to a considerable extent, the product of what Robert F. Harney termed the Italo-phobia of the English-speaking world. English-speakers’ understandings of race and their history of anti-Catholicism helped to create an ideological foundation for fixing foreignness upon urban spaces occupied by immigrants who seemed racially different from the earlier Anglo-Celtic and northern European settlers.
High Ambient Temperature Reduces Rate of Body-Weight Loss Produced by Wheel Running
Authors: Gutiérrez Emilio , Baysari Melissa T. , Carrera Olaia , Whitford Thomas J. , Boakes Robert A.
Published: February 2006

This study examined the effect of ambient temperature (AT) on the relationship between activity and weight loss. Compared with a neutral AT of 21°C, high ATs of 27–29°C produced a slower rate of weight loss in rats given 1.5-hr food access and 22.5-hr running-wheel access in a standard activity-based anorexia (ABA) procedure (Experiments 1 and 2). The high AT did not affect food intake or wheel running in Experiment 1, but did reduce running in Experiment 2. Switching from neutral to high AT had only a transient effect on weight loss when wheel access was maintained (Experiment 2) but resulted in less weight loss when wheel access was prevented (Experiment 3). Giving rats only 3 hr of wheel access each day at a neutral AT also produced substantial weight loss, but less if for the rest of each day they were maintained at a high AT (Experiment 4).
Management of Occupational Exposures to Hepatitis C Virus Current Practice and Controversies
Authors: Alvarado-Ramy Francisco , Alter Miriam J. , Bower William , Henderson David K. , Sohn Annette H. , Sinkowitz-Cochran Ronda L. , Jarvis William R.
Published: February 2006

Unlike hepatitis B virus and human immunodeficiency virus, there currently are no immunization or chemoprophylactic interventions available to prevent infection after an occupational exposure to hepatitis C virus (HCV). A “Reality Check” session was held at the 4th Decennial International Conference on Nosocomial and Healthcare-Associated Infections to gather information on current practices related to management of occupational exposures to HCV, generate discussion on controversial issues, and identify areas for future research. Infection control professionals in attendance were knowledgeable in most issues addressed regarding the management of occupational exposures to HCV. Areas of controversy included the use of antiviral therapy early in the course of HCV infection and the appropriate administrative management of an HCV-infected healthcare worker.
Clostridium difficile- Associated Diarrhea in a VA Medical Center Clustering of Cases, Association With Antibiotic Usage, and Impact on HIV-infected Patients
Authors: Mody Lona R. , Smith Sharon M. , Dever Lisa L.
Published: February 2006

A case-control study of patients with stools assayed forClostridium difficiletoxin over a 24-month period at a Veterans Affairs hospital found that the majority of cases (70.6%) occurred in temporal clusters. Clustering was particularly evident on a designated human immunodeficiency virus (RW) unit. Thirty-four (75.5%) of 45 HIV-infected patients withC difficile-associated diarrhea (CDAD) died during their hospitalization. Third-generation cephalosporins were the antibiotics most strongly associated with CDAD.
Invasive Aspergillosis Outbreak on a Hematology-Oncology Ward
Authors: Burwen Dale R. , Lasker Brent A. , Rao Nalini , Durry Elias , Padhye Arvind A. , Jarvis William R.
Published: February 2006

An outbreak of invasive aspergillosis occurred in a community hospital in temporal association with construction activity. Epidemiological investigation showed that patients who are at highest risk comprise a small group and are readily identifiable. Clinicians should strive to protect these patients, following guide-lines published by the Centers for Disease Control and Prevention.
Tap Water Colonization With Psmdomonas aeruginosa in a Surgical Intensive Care Unit (ICU) and Relation to Psmdomonas Infections of ICU Patients
Authors: Trautmann Matthias , Michalsky Thomas , Wiedeck Heidemarie , Radosavljevic Vladan , Ruhnke Markus
Published: February 2006

Water faucets on a surgical intensive care ward were examined prospectively as a source of Pseudomonas aeruginosa infections. All water outlets harbored distinct genotypes of P aeruginosa over prolonged time periods. Over a period of 7 months, 5 (29%) of 17 patients were infected with P aeruginosa genotypes also detectable in tap water.
Application of the IDSA Guidelines for the Use of Antimicrobial Agents in Neutropenic Patients: Impact on Reducing the Use of Glycopeptides
Authors: Nucci Marcio , Landau Marianne , Silveira Fernanda , Spector Nelson , Pulcheri Wolmar
Published: February 2006

We evaluated the impact of applying the Infectious Diseases Society of America guidelines for febrile neutropenic patients in reducing the use of glycopeptides. Forty-five prior episodes of febrile neutropenia were compared to 97 episodes seen after application of the guidelines. Glycopeptide use was reduced from 73% to 43% of episodes (P=.0008), without changes in outcome.
Bacterial Contamination of Fabric Stethoscope Covers: The Velveteen Rabbit of Health Care?
Authors: Milam Michael W. , Hall Melanie , Pringle Teri , Buchanan Kay
Published: February 2006

To determine if fabric stethoscope covers pose an infection control problem, we studied how they are cared for by our healthcare workers and performed microbiological investigations on 22 covers collected over a 3-week period. Our study suggests that fabric stethoscope covers represent a potential infection control problem because they are used for prolonged periods, are infrequently laundered, and are contaminated with bacteria.
Surveillance and Control of Methicillin-ResistantStaphylococcus aureusInfections in French Hospitals
Authors: Lepelletier Didier , Richet Hervé
Published: February 2006

Objective:

To assess the way French hospitals conduct surveillance for, and control infections caused by, methicillin-resis-tantStaphylococcus aureus(MRSA), and to evaluate the incidence of these infections.

Design:

Retrospective analysis of sample surveillance data.

Setting:

Representative sample of French hospitals.

Participants:

Representative sample of 38 French public hospitals.

Methods:

Hospitals were selected randomly in 1996, taking into account their location and number of beds. Administrative data, surveillance denominators used, antimicrobial resistance rates, and infection control practices were analyzed for the period 1990 to 1995. The same 38 centers were contacted 3 years later, in 1998, to reassess their surveillance and control activities.

Results:

French hospitals were slow to implement MRSA surveillance programs; only 5% had such programs in 1990, when the median incidence per admission (0.37%) and per patient-days (0.04%) of MRSA infections was already high. Despite the implementation of surveillance programs in 66% of French hospitals in 1995 and 87% in 1998, the MRSA infection rates remained stable from 1990 to 1995 and increased from 1995 to 1998. The proportion of French hospitals having a policy for the transfer of MRSA-infected patients to other hospitals increased from 47% in 1995 to 61% in 1998, whereas screening for MRSA colonization (42%-53%) and isolation for colonized or infected patients (87%-89%) remained stable.

Conclusions:

This first national survey showed that French hospitals probably were not optimally prepared to control and prevent MRSA infections, since they were slow to respond to the growing problem.
Neonatal Bacteremia: Patterns of Antibiotic Resistance
Authors: Bromiker Ruben , Arad Ilan , Peleg Ofra , Preminger Aviya , Engelhard Dan
Published: February 2006

Objective:

To determine the incidence and evaluate the antimicrobial-susceptibility patterns of bacterial infections in our neonatal units.

Design:

Retrospective surveillance study.

Setting:

The neonatal units of the Hadassah University Hospitals, Jerusalem, Israel.

Patients:

All newborns admitted from January 1994 through February 1999.

Methods:

The records of all patients with positive blood and cerebrospinal fluid cultures were reviewed. Bacteremia was considered early-onset (vertical) when occurring within the first 72 hours of life and late-onset (nosocomial) when occurring later. The prevalence and antibiotic-resistance patterns of vertically transmitted and nosocomially acquired strains were compared and studied over time.

Results:

219 of 35,691 newborn infants had at least one episode of bacteremia (6.13/1,000 live births). There were 305 identified organisms, of which 21% (1.29/1,000 live births) were considered vertically transmitted and 79% nosocomially acquired. The most common organism causing early-onset disease (29.2%) was group B streptococcus (0.38/1,000 live births), whereas coagulase-negative staphylococci (51%) were the most prevalent in late-onset disease. All gram-positive bacteria were susceptible to vancomycin. Most gram-positive organisms other than staphylococci were susceptible to ampicillin. Gram-negative organisms represented 31% of all isolates. Generally, there was a trend of increasing resistance to commonly used antibiotics among nosocomially acquired gram-negative organisms, compared to those vertically transmitted, with statistically significant differences for ampicillin and mezlocillin (P<.05 andP<.01, respectively). Over the years, a trend toward an increasing resistance to antibiotics was observed among gram-negative organisms.

Conclusions:

The trend of increasing bacterial resistance to commonly used antibiotics necessitates the implementation of a rational empirical treatment strategy, based on local susceptibility data, reserving certain agents for emerging resistant pathogens.
Epidemiology of Biological-Exposure Incidents Among Spanish Healthcare Workers
Authors: Monge Vicente , Mato Gloria , Mariano Alberto , Fernández Cristina , Fereres José ,   GERABTAS Working Group
Published: February 2006

Objective:

To determine the frequency and the epidemiological characteristics of biological-exposure incidents occurring among healthcare personnel.

Design:

Prospective surveillance study.

Setting:

Participating Spanish primary-care and specialty centers from January 1994 to December 1997.

Participants:

70 centers in 1994, 87 in 1995, 97 in 1996, and 104 in 1997.

Methods:

Absolute and relative frequencies were calculated for several variables (position held, area of care, type of injuring object, activity, etc) and for the different categories of each variable.

Results:

There were 20,235 registered incidents. Annual incidence rates were as follows: 1994, 51 per 1,000; 1995, 58 per 1,000; 1996, 54 per 1,000; and 1997, 59 per 1,000. Mean age of accident victims was as follows: 1994, 35.68 (standard deviation [SD], 16.26); 1995, 33.6 (SD, 11.9); 1996, 38.2 (SD, 17.27); and 1997, 36.7 (SD, 16.33) years. Of the 20,235 incidents, 15,860 (80.7%) occurred to women; 50% (9,833) accidents were among nursing staff. The type of incident most frequently reported was percutaneous injury (81.1%). The highest frequency of accidents was seen in medical and surgical areas (28% and 25.6%, respectively). Blood and blood products were the most commonly involved material (87.6%). Administration of intramuscular or intravenous medication was the activity associated with the highest accident rate (20.3%). The most frequent immediate action in response was rinsing and disinfecting (65.6%).

Conclusions:

The incident registry was highly stable in terms of incidence rates over the observation period and served to highlight the large number of incidents recorded each year. The potential implications of die results are the need to explore reasons for increased exposures in certain areas, with the aim of focusing prevention efforts, and, similarly, to establish the factors associated with diminished incidence rates to model successful measures.
Hospital Bloodborne Pathogens Programs: Program Characteristics and Blood and Body Fluid Exposure Rates
Authors: Beekmann Susan E. , Vaughn Thomas E. , McCoy Kimberly D. , Ferguson Kristi J. , Torner James C. , Woolson Robert F. , Doebbeling Bradley N.
Published: February 2006

Objective:

To describe hospital practices and policies relating to bloodborne pathogens and current rates of occupational exposure among healthcare workers.

Participants and Methods:

Hospitals in Iowa and Virginia were surveyed in 1996 and 1997 about Standard Precautions training programs and compliance. The primary outcome measures were rates of percutaneous injuries and mucocutaneous exposures.

Results:

153 (64%) of 240 hospitals responded. New employee training was offered no more than twice per year by nearly one third. Most (79%-80%) facilities monitored compliance of nurses, housekeepers, and laboratory technicians; physicians rarely were trained or monitored. Implementation of needlestick prevention devices was the most common action taken to decrease sharps injuries. Over one half of hospitals used needleless intravenous systems; larger hospitals used these significantly more often. Protected devices for phlebotomy or intravenous placement were purchased by only one third. Most (89% of large and 80% of small) hospitals met the recommended infection control personnel-to-bed ratio of 1:250. Eleven percent did not have access to postexposure care during all working hours. Percutaneous injury surveillance relied on incident reports (99% of facilities) and employee health records (61%). The annual reported percutaneous injury incidence rate from 106 hospitals was 5.3 injuries per 100 personnel. Compared to single tertiary-referral institution rates determined more than 5 years previously, current injury rates remain elevated in community hospitals.

Conclusions:

Healthcare institutions need to commit sufficient resources to Standard Precautions training and monitoring and to infection control programs to meet the needs of all workers, including physicians. Healthcare workers clearly remain at risk for injury. Further effective interventions are needed for employee training, improving adherence, and providing needlestick prevention devices.
Development of Minimum Criteria for the Initiation of Antibiotics in Residents of Long-Term–Care Facilities: Results of a Consensus Conference
Authors: Loeb Mark , Bentley David W. , Bradley Suzanne , Crossley Kent , Garibaldi Richard , Gantz Nelson , McGeer Allison , Muder Robert R. , Mylotte Joseph , Nicolle Lindsay E. , Nurse Brenda , Paton Shirley , Simor Andrew E. , Smith Philip , Strausbaugh Larry
Published: February 2006

Establishing a clinical diagnosis of infection in residents of long-term–care facilities (LTCFs) is difficult. As a result, deciding when to initiate antibiotics can be particularly challenging. This article describes the establishment of minimum criteria for the initiation of antibiotics in residents of LTCFs. Experts in this area were invited to participate in a consensus conference. Using a modified delphi approach, a questionnaire and selected relevant articles were sent to participants who were asked to rank individual signs and symptoms with respect to their relative importance. Using the results of the weighting by participants, a modification of the nominal group process was used to achieve consensus. Criteria for initiating antibiotics for skin and soft-tissue infections, respiratory infections, urinary infections, and fever where the focus of infection is unknown were developed.
New-Onset Rhinitis Symptoms Among Hospitalized Patients: Are Flowers a Culprit?
Authors: Manian Farrin A.
Published: February 2006

New-onset rhinitis symptoms following admission to the hospital were reported by 12.7% of surveyed patients. Presence of flower arrangements in the proximity of patients' beds was highly associated with the development of new rhinitis (odds ratio, 9.7; 95% confidence interval, 4.3-21.7), or what may be more aptly referred to as “florocomial” rhinitis.
A Blinded Comparison of Three Laboratory Protocols for the Identification of Patients Colonized With Methicillin-Resistant Staphylococcus aureus
Authors: Gardam Michael , Brunton James , Willey Barbara , McGeer Allison , Low Donald , Conly John
Published: February 2006

Objective:

To compare three laboratory screening protocols for the detection of methicillin-resistantStaphylococcus aureus(MRSA) from surveillance specimens (mannitol-salt agar containing 2 μg/mL of oxacillin [MSA-2], mannitol-salt agar containing 4 μg/mL of oxacillin [MSA-4], and a broth-containing protocol as recommended by the American Society for Microbiology [M-ASM]).

Design:

Blinded comparative laboratory study and cost analysis.

Setting:

University-affiliated microbiology laboratory.

Methods:

Outcome measurements included rate of detection of MRSA-positive specimens and patients, turnaround time, and media and technologist costs. All MRSA culture swabs obtained from any patient site from November 1998 to April 1999 were included.

Results:

The M-ASM protocol detected between 19.1% and 32.0% more MRSA-positive specimens and between 13.3% and 23.3% more MRSA-positive patients per surveillance event than the MSA-4 and MSA-2 protocols, respectively. There was no difference in positive-culture reporting time between the M-ASM and MSA-4 protocols. The broth-containing protocol was 2- to 2.5-fold more expensive than the simpler protocols, taking into account media and laboratory personnel costs.

Conclusions:

It remains to be determined whether it is cost beneficial for a hospital to adopt the M-ASM, as the potential cost of MRSA transmission from unidentified MRSA-colonized patients is unknown. A broth-containing protocol should be considered the gold standard in future studies examining newer MRSA screening protocols.
Blood Products: A Significant Risk Factor for Long-Term Catheter-Related Bloodstream Infections in Cancer Patients
Authors: Hanna Hend A. , Raad Issam
Published: February 2006

Data obtained from a previous prospective randomized study in cancer patients conducted at our institution were analyzed to investigate risk factors for catheter-related (CR) bloodstream infections (BSIs). Our recent analysis showed that the administration of blood products through central venous catheters was a risk factor for CR BSI, whereas thrombocytopenia during catheterization may have provided protection against CR BSI, as did central venous catheter insertion under maximal sterile barrier precautions.
Urinary Tract Infections in Long-Term–Care Facilities
Authors: Nicolle Lindsay E. ,   SHEA Long-Term–Care Committee
Published: February 2006

Urinary tract infection (UTI) is the most common bacterial infection occurring in residents of long-term–care facilities. It is a frequent reason for antimicrobial administration, but antimicrobial use for treating UTIs is often inappropriate. Achieving optimal management of UTI in this population is problematic because of the very high prevalence of bacteriuria, evidence that the treatment of asymptomatic bacteriuria is not beneficial, and the clinical and microbiological imprecision in diagnosing symptomatic UTI. This position paper has been developed, using available evidence, to assist facilities and healthcare professionals in managing this common problem.
Bacterial Contamination Associated With Electronic Faucets: A New Risk for Healthcare Facilities
Authors: Hargreaves James , Shireley Larry , Hansen Shannon , Bren Virginia , Fillipi Gordon , Lacher Craig , Esslinger Virginia , Watne Terry
Published: February 2006

Objective:

To investigate the safety of the hospital water supply following a major flood.

Design:

Surveillance was conducted of the hospital water supply as it entered the hospital and at randomly selected water faucets throughout the facility.

Setting:

A newly constructed surgical critical-care unit in a 265-bed community hospital that had to be evacuated and was out of operation for 6 weeks following a major flood of the city.

Methods:

Random water samples throughout the facility were analyzed for heterotrophic plate counts (HPCs), chlorine, and coliforms utilizing standard methods.

Results:

Water samples entering the hospital met appropriate standards, indicating the city water distribution system was not contaminated. Of 169 faucets tested, 13 (22%) of 59 electronic faucets exceeded the HPC threshold, and 12 (11%) of 110 manual faucets exceeded the HPC threshold (P<.14). A comparison of two brands of electronic faucets with manual faucets and with each other revealed that the HPC threshold was exceeded by 11 (32%) of 34 brand A faucets as compared to 12 (11%) of 110 manual faucets (P<.006). The HPC threshold was exceeded by 2 (8%) of 25 brand B faucets compared to 12 (11%) of 110 manual faucets (P<.94). Contamination rates of brand A and brand B faucets differed significantly (P<.003). Similar testing 2 months after hyperchlorination of the water supply indicated that the HPC threshold was exceeded by 16 (52%) of 31 brand A faucets compared to 10 (9.%) of 110 manual faucets (P<.0000003) and by 2 (18%) of 25 brand B faucets compared to 10 (9%) of 110 manual faucets (P=1.0).

Conclusions:

A certain brand of electronic water faucet used in the hospital was associated with unacceptable levels of microbial growth in water and was a continuing source of bacteria potentially hazardous to patients.
Methicillin-ResistantStaphylococcus aureusin Two Tertiary-Care Centers in Jeddah, Saudi Arabia
Authors: Madani Tariq A. , Al-Abdullah Nabeela A. , Al-Sanousi Ali A. , Ghabrah Tawfik M. , Afandi Shadia Z. , Bajunid Huda A.
Published: February 2006

Objective:

To review clinical experience with methicillin-resistantStaphylococcus aureus(MRSA) in tertiary-care hospitals in Jeddah, Saudi Arabia.

Design:

Retrospective review for the year 1998.

Setting:

Two tertiary-care hospitals.

Methods:

Results of MRSA-positive cultures of clinical specimens obtained as part of investigations for suspected infections were retrieved from the microbiology laboratories' records. Charts of patients were reviewed, with standardized data collection.

Results:

Of 673S aureusisolates identified, 222 (33%, or 6.8 isolates/1,000 admissions) were MRSA Overall MRSA prevalence was 2% in 1988. Nosocomial acquisition occurred in 84.2% of cases. All age groups were affected, and 52% of patients had at least one comorbidity. MRSA prevalence was highest in the intensive care units (26.6% of all isolates), the medical wards (24.8%), and the surgical wards (19.8%). Seventy-three percent of isolates caused infection; the rest represented colonization. Surgical wounds (35.2%), the chest (29%), and central venous catheters (13%) were the most common sites of infection. Bacteremia occurred in 15.4% of patients. Local signs (84%) and fever (75.9%) were the most common clinical manifestations. Respiratory distress and septic shock occurred in 30.2% and 13.6% of cases, respectively. Of 162 patients with MRSA infection and 60 patients with MRSA colonization, 95.7% and 70% received antibiotics in the preceding 6 weeks, respectively (P<.0001). The total mortality of patients with MRSA infection was 53.7%: 36.4% as a result of MRSA infection and 17.3% as a result of other causes.

Conclusions:

The prevalence of MRSA is high and rapidly increasing in the two hospitals, as it is worldwide. Control measures to prevent die spread of MRSA in hospitals should continue, with reinforcement of hygienic precautions and development of policies to restrict the use of antibiotics.
Management of an Outbreak of Vancomycin-Resistant Enterococci in the Medical Intensive Care Unit of a Cancer Center
Authors: Hanna Hend , Umphrey Jan , Tarrand Jeffrey , Mendoza Michelle , Raad Issam
Published: February 2006

Between November 1996 and February 1997, 17 episodes of vancomycin-resistant enterococci (VRE) infection or colonization (9 infections, 8 colonizations), all with the same or a similar genomic DNA pattern, were identified in the medical intensive care unit (MICU) of a tertiary-care cancer hospital. The cases were genotypically traced to a patient who was admitted to the hospital in September 1996 and who, by December 1996, had four different admissions to the MICU. Multifaceted infection control measures, including decontamination of the environment and of nondisposable equipment, halted the nosocomial transmission of VRE in the MICU.
Infection Control Dogma: Top 10 Suspects
Authors: Manangan Lilia P. , Pugliese Gina , Jackson Marguerite , Lynch Patricia , Sohn Annette H. , Sinkowitz-Cochran Ronda L. , Jarvis William R.
Published: February 2006

As infection control evolved into an art and science through the years, many infection control practices have become infection control dogmas (principles, beliefs, ideas, or opinions). In this “Reality Check” session of the 4th Decennial International Conference on Nosocomial and Healthcare-Associated Infections, we assessed participants' perceptions of prevalent infection control dogmas. The majority of participants agreed with all dogmas having evidence of efficacy, except for the dogma on the frequency of changing mechanical-ventilator tubing. In contrast, the majority of participants disagreed with dogmas not having evidence of efficacy, except for the dogma on perineal care, umbilical cord care, and reminder signs for isolation precaution. As for controversial dogmas, many of the responses were almost evenly distributed between “agree” and “disagree.” Infection control professionals were knowledgeable about evidence-based infection control practices. However, many of the respondents still believe in some of the non–evidence-based dogmas.
A Review of Single-Use and Reusable Gowns and Drapes in Health Care
Authors: Rutala William A. , Weber David J.
Published: February 2006

Gowns and drapes are used widely in healthcare facilities. Gowns have been used to minimize the risk of disease acquisition by healthcare providers, to reduce the risk of patient-to-patient transmission, and during invasive procedures to aid in maintaining a sterile field. Drapes have been used during invasive procedures to maintain the sterility of environmental surfaces, equipment, and patients. This article reviews the use of gowns and drapes in healthcare facilities, including the characteristics, costs, benefits, and barrier effectiveness of single-use and reusable products.

Currently, gowns protect healthcare personnel performing invasive procedures from contact with bloodborne pathogens. Although gowns have been recommended to prevent patient-to-patient transmission in certain settings (eg, neonatal intensive care unit) and for certain patients (eg, those infected with vancomycin-resistant enterococci), scientific studies have produced mixed results of their efficacy. While appropriate use of drapes during invasive procedures is recommended widely as an aid in minimizing contamination of the operative field, the efficacy of this practice in reducing surgical-site infections has not been assessed by scientific studies.

Based on an evaluation of the functional requirements, environmental impact, and economics of gowns and drapes, clear superiority of either reusable or single-use gowns and drapes cannot be demonstrated. The selection of particular gowns and drapes by individual healthcare facilities requires an assessment of the facility's requirements, available products, and costs and should be based on the desired characteristics of an ideal gown or drape as defined in this paper.
Nosocomial Rotavirus in a Pediatric Hospital
Authors: Ratner Adam J. , Neu Natalie , Jakob Kathleen , Grumet Surah , Adachi Nora , Della-Latta Phyllis , Marvel Edith , Saiman Lisa
Published: February 2006

We describe a nosocomial rotavirus outbreak among pediatric cardiology patients and the impact of a prospective, laboratory-based surveillance program for rotavirus in our university-affiliated, quartenary-care pediatric hospital in New York City. Improved compliance with infection control and case-finding among patients and healthcare workers halted the outbreak.
The Chronic Indwelling Catheter and Urinary Infection in Long-Term–Care Facility Residents
Authors: Smith Philip W. , Nicolle Lindsay E.
Published: February 2006

From 5% to 10% of residents of long-term–care facilities have urinary drainage managed with chronic indwelling catheters. These residents are always bacteriuric, usually with a complex microbiological flora of two to five organisms and a biofilm on the catheter that may contribute to obstruction. Residents with chronic indwelling catheters have increased morbidity from urinary infection compared to bacteriuric residents without chronic catheters. The most effective means to prevent infection is limitation of chronic indwelling catheter use. While appropriate catheter care and infection control precautions are recommended in managing these patients, the impact of these practices on the occurrence of urinary infection or prevention of symptomatic episodes has not been evaluated. Symptomatic infection can likely be prevented by attention to catheter care, including early recognition and replacement of obstructed catheters and prevention of catheter trauma. Appropriate use of prophylactic antimicrobial therapy prior to invasive genitourinary procedures is also necessary. Asymptomatic bacteriuria should not be treated. When symptomatic episodes occur, patients should be evaluated clinically and microbiologically and treated with appropriate antimicrobial therapy. Further technological advances in catheter material and urine drainage will be needed to have a substantial impact on the frequency of urinary infection with chronic catheter use.
HACCP and Food Hygiene in Hospitals Knowledge, Attitudes, and Practices of Food-Services Staff in Calabria, Italy
Authors: Angelillo Italo F. , Viggiani Nunzia M.A. , Greco Rosa M. , Rito Daniela ,   Collaborative Group
Published: February 2006

Objectives:

To determine adherence to Hazard Analysis and Critical Control Points (HACCP) methods and to evaluate knowledge, attitudes, and practices of food-services staff with regard to food hygiene in hospitals.

Design:

A survey.

Participants:

Hospital medical directors and food-services staff of 36 hospitals in Calabria, Italy.

Methods:

A questionnaire about hospital characteristics, food-services organization, and measures and procedures for the control and prevention of foodborne diseases was sent to medical directors; a questionnaire about demographic and practice characteristics, knowledge, attitudes, and behaviors about control and prevention of foodborne diseases was sent to food-services staff. Multiple logistic regression analysis was performed.

Results:

Only 54% of the 27 responding hospitals were using the HACCP system and, of those using HACCP, 79% adopted a food-hygiene–practice manual; more than one half already had developed written procedures for food storage, personal hygiene, cleaning and disinfection; one half or less performed microbiological assessment of foods and surfaces. Of the 290 food-services staff who responded, 78.8% were aware of the five leading food-borne pathogens; this knowledge was significantly higher among those with a higher educational level and those who worked in hospitals that had implemented the HACCP system. Younger staff and those who had attended continuing educational courses about food hygiene and hospital foodborne diseases had a significantly higher knowledge of safe temperatures for food storage. A positive attitude toward foodborne-diseases prevention was reported by the great majority, and it was significantly higher in older respondents and in those working in hospitals with a lower number of beds. Only 54.9% of those involved in touching or serving unwrapped raw or cooked foods routinely used gloves during this activity; this practice was significantly greater among younger respondents and in those working in hospitals using HACCP.

Conclusion:

Full implementation of the HACCP system and infection control policies in hospital food services is needed.
Differences in Antimicrobial Susceptibility Among Hospitals in an Integrated Health System
Authors: Lubowski Teresa J. , Woon John L. , Hogan Patricia , Hwang Ching-Chang
Published: February 2006

We evaluated the differences in antimicrobial susceptibility among hospitals in three different integrated healthcare systems. Each system provided antibiogram-susceptibility reports from representative hospitals. Reports were analyzed for statistically significant differences between hospitals in a given system for nine important organisms. We found numerous significant interhospital differences in antimicrobial-susceptibility patterns within health systems. For this reason, the practice of combining antibiotic-susceptibility data into a systemwide antibiogram should be discouraged.