bluuebunny/crossref_metadata_2025 huggingface dataset:
Bupropion in breast milk: an exposure assessment for potential treatment to prevent post-partum tobacco use
Authors: Haas J S , Kaplan C P , Barenboim D , Jacob P , Benowitz N L
Published: February 2004

Objectives:To assess potential infant exposure to bupropion and its active metabolites in breast milk such as would occur during treatment to prevent post-partum relapse to tobacco use, and to compare the concentrations of bupropion in urine and saliva with plasma and breast milk.

Design and setting:Cohort study, outpatient clinical research centre.

Subjects:Ten healthy post-partum volunteers who agreed to take bupropion for seven days, pump and discard their breast milk, and have samples of breast milk, plasma, saliva, and urine analysed.

Intervention:Bupropion 150 mg a day for three days and then 300 mg a day for four days.

Main outcome measures:Concentrations of bupropion and its active metabolites (hydroxybupropion, erythrohydrobupropion, threohydrobupropion) in breast milk, plasma, saliva, and urine. Determination of average infant exposure.

Results:The calculated average dosage of bupropion in breast milk was 6.75 μg/kg/day. Therefore, the average infant exposure is 0.14 % of the standard adult dose of bupropion, corrected for the difference in body weight. Considering the sum of bupropion and its active metabolites, the average infant exposure is expected to be 2% of the standard maternal dose on a molar basis. The concentration of bupropion and its active metabolites in breast milk was not associated with age, body mass index, use of oral contraceptive pills, age of infant, or the frequency of breast feeding at the time the study was initiated. The coefficient of determination (r2) between the concentration of bupropion in breast milk and in urine was 0.77 (p < 0.01).

Conclusions:Bupropion and its active metabolites are present in the breast milk of lactating women. The concentrations of bupropion in breast milk and urine were highly correlated. These results indicate that the daily dose of bupropion and metabolites that would be delivered to an infant of a woman taking a therapeutic dose of bupropion is small. These results suggest that the effectiveness of bupropion to prevent post-partum relapse to tobacco use should be evaluated without excluding women who plan to breast feed.
Tobacco industry litigation to deter local public health ordinances: the industry usually loses in court: Table 1
Authors: Nixon M L , Mahmoud L , Glantz S A
Published: February 2004

Background:The tobacco industry uses claims of state preemption or violations of the US Constitution in litigation to overturn local tobacco control ordinances.

Methods:Collection of lawsuits filed or threatened against local governments in the USA; review of previously secret tobacco industry documents; interviews with key informants.

Results:The industry is most likely to prevail when a court holds that there is explicit preemption language by the state legislature to exclusively regulate tobacco. The industry has a much weaker record on claims of implied preemption and has lost all challenges brought under equal protection claims in the cases we located. Although the tobacco industry is willing to spend substantial amounts of money on these lawsuits, it never won on constitutional equal protection grounds and lost or dropped 60% (16/27) of the cases it brought claiming implied state preemption.

Conclusions:Municipalities should continue to pass ordinances and be prepared to defend them against claims of implied preemption or on constitutional grounds. If the ordinance is properly prepared they will likely prevail. Health advocates should be prepared to assist in this process.
Intervention to reduce environmental tobacco smoke exposure in Latino children: null effects on hair biomarkers and parent reports: Table 1
Authors: Conway T L , Woodruff S I , Edwards C C , Hovell M F , Klein J
Published: February 2004

Objective:To evaluate the effectiveness of a lay delivered intervention to reduce Latino children’s exposure to environmental tobacco smoke (ETS). The a priori hypothesis was that children living in households that were in the intervention group would have lower exposure over time than measurement only controls.

Design:A two group, randomised control trial was conducted.

Setting:Areas of San Diego county with a large Latino population.

Participants:143 Latino parent–child pairs.

Intervention:Trained bicultural and bilingual Latina lay community health advisors, orpromotoras, conducted problem solving aimed at lowering the target child’s exposure to ETS in the household. Six home and telephone sessions were delivered by thepromotorasover a four month period.

Main outcome measures:Outcome measures were collected at baseline, immediately post-intervention, three months post-intervention, and 12 months post-intervention. Four outcomes were considered: (1) parent’s paper-and-pencil reports of the child’s past month exposure; (2) hair samples from the child analysed for past month nicotine; (3) hair samples from the child analysed for past month cotinine; and (4) per cent confirmed reducers.

Results:There were no significant condition-by-time interactions, the term indicative of a differential intervention effect. Significant or near significant time main effects were seen for children’s hair cotinine, per cent confirmed reducers, and, in particular, parent reports of exposure.

Conclusions:Applying a laypromotoramodel to deliver the behavioural problem solving intervention unfortunately was not effective. A likely explanation relates to the difficulty of delivering a relatively complex intervention by lay women untrained in behaviour change theory and research methods.
A study of smoking and smoking cessation on the curricula of UK medical schools
Authors: Roddy E , Rubin P , Britton J
Published: February 2004

Objectives:To identify current practice in teaching on smoking and smoking cessation in UK medical schools, and establish whether newly qualified UK doctors feel prepared to deliver smoking cessation interventions.

Design:Search of published curricula from all UK medical schools; questionnaire surveys of all UK medical school deans and UK qualified pre-registration house officers (PRHOs).

Participants:Deans or nominated representatives from all 24 UK medical schools with current undergraduates, and all UK qualified PRHOs.

Main outcome measures:Inclusion and organisation in curriculum of 15 predefined core topics related to smoking (deans); perceived readiness to deliver smoking cessation interventions (PRHOs).

Results:There was no mention of smoking or smoking cessation in the published curriculum material of 10 (42%) medical schools. Deans reported compulsory teaching on a mean (SD) of 9.5 (2.8) core topics, while PRHOs recalled compulsory teaching in only 6.6 (3.2). Training in clinical aspects of smoking cessation was particularly neglected, with 60% of PRHOs reporting that they graduated unable to deliver smoking cessation interventions in accordance with national guidelines. Only 17% of PRHOs felt well prepared to deliver advice on using nicotine replacement therapy, and 5% on bupropion.

Conclusions:Teaching on smoking cessation in UK medical schools is inadequate.
A tobacco industry study of airline cabin air quality: dropping inconvenient findings
Authors: Neilsen K , Glantz S A
Published: February 2004

Objective:To examine an industry funded and controlled study of in flight air quality (IFAQ).

Methods:Systematic search of internal tobacco industry documents available on the internet and at the British American Tobacco Guildford Depository.

Results:Individuals from several tobacco industry companies, led by Philip Morris, designed, funded, conducted, and controlled the presentation of results of a study of IFAQ for the Scandinavian airline SAS in 1988 while attempting to minimise the appearance of industry control. Industry lawyers and scientists deleted results unfavourable to the industry’s position from the study before delivering it to the airline. The published version of the study further downplayed the results, particularly with regard to respirable suspended particulates. The study ignored the health implications of the results and instead promoted the industry position that ventilation could solve problems posed by secondhand smoke.

Conclusions:Sponsoring IFAQ studies was one of several tactics the tobacco industry employed in attempts to reverse or delay implementation of in-flight smoking restrictions. As a result, airline patrons and employees, particularly flight attendants, continued to be exposed to pollution from secondhand smoke, especially particulates, which the industry’s own consultants had noted exceeded international standards. This case adds to the growing body of evidence that scientific studies associated with the tobacco industry cannot be taken at face value.
Changes in population attitudes about where smoking should not be allowed: California versus the rest of the USA
Authors: Gilpin E A , Lee L , Pierce J P
Published: February 2004

Background:The decade long California Tobacco Control Program is unique to the nation in its duration, emphasis, and level of funding. Programme emphasis is on changing social norms about smoking as a means to discourage smoking and thus reduce the harmful health effects of tobacco to the population.

Methods:Data from the 1992–93, 1995–96, and 1998–99 Tobacco Use Supplements to the national Current Population Survey (n > 175 000 each period) were used to examine changes in norms regarding where smoking should “not be allowed at all” in both California and in the rest of the USA. Venues queried were restaurants, hospitals, work areas, bars, indoor sports venues, and indoor shopping malls.

Results:There were substantial increases in the percentages of the adult population (18+ years) stating that smoking should not be allowed in the venues queried in California by 1998–99 compared to 1992–93; only modest increases were observed in the rest of the USA. In fact, for most venues, the percentages for the rest of the USA were lower in 1998–99 than in California in 1992–93. Further, the percentage increase over this period in respondents stating that smoking should not be allowed in four or more of the six venues was 30% in California and 23% in the rest of the USA. The most dramatic percentage increase in California occurred among current smokers (93%).

Conclusions:A strong, comprehensive tobacco control programme such as California’s can influence population norms, including those of smokers, with respect to where smoking should not be allowed.
Smoker and ex-smoker reactions to cigarettes claiming reduced risk
Authors: Shiffman S , Pillitteri J L , Burton S L , Di Marino M E
Published: February 2004

Context:The tobacco industry is introducing modified tobacco products claiming to reduce the risk of smoking (potential reduced exposure products, PREPs). If PREPs are perceived as safe, they may deter smokers from quitting and encourage re-initiation by smokers who have quit.

Objective:To assess smokers’ and ex-smokers’ perceptions of PREPs and the impact of PREP claims on interest in quitting (among smokers) or in resuming smoking (ex-smokers).

Design:A random-digit-dialled survey of US smokers and ex-smokers. We used Eclipse, a modified PREP cigarette, as an exemplar PREP. During the survey, the interviewer read risk reduction claims made for Eclipse by its manufacturer, assessing smokers’ interest in quitting before and after the exposure.

Participants:1000 current cigarette smokers and 499 ex-smokers (300 quit within the last two years), over 18 years old.

Main outcome measures:Perception of risk reduction from Eclipse; interest in using Eclipse; smokers’ interest in quitting was assessed using a stage of change approach (pre- and post-exposure to claims).

Results:91% of smokers thought Eclipse was safer than regular cigarettes. 24% believed Eclipse was completely safe. 57.4% of smokers were interested in using Eclipse; interest was greatest among smokers who were contemplating quitting. Exposure to Eclipse’s claims was followed by reduced interest in quitting. Among all ex-smokers, interest in Eclipse was 6.2%, but interest was 15.2% among young adults (18–25 years) who had stopped smoking within two years.

Conclusions:There is substantial risk that smokers will overinterpret reduced risk claims made for modified tobacco products. PREPs appeal to smokers who are contemplating quitting and exposure to reduced risk product claims appears to reduce smokers’ readiness to quit. PREPs also appealed to young adults who had recently stopped smoking. Thus, reduced risk tobacco product claims can undermine adult cessation and youth prevention, possibly resulting in increased harm even if the products are less toxic.
Airport smoking rooms don’t work
Authors: Pion M , Givel M S
Published: February 2004

Objectives:To document tobacco industry involvement in thwarting enactment of a smoke-free airport policy at Lambert-St Louis International Airport (Lambert Airport) in the 1990s; and to test whether smoking rooms at Lambert Airport protect non-smokers from exposure to secondhand tobacco smoke (SHS) in adjacent non-smoking areas.

Methods:Tobacco industry document websites were searched for previously secret documents relating to efforts to maintain smoking in Lambert Airport. Testing of SHS contamination in non-smoking areas adjacent to a designated smoking room was conducted at Lambert Airport in 1997–98 and again in 2002. A 1998 comparative test was also performed inside nominally smoke-free Seattle-Tacoma International Airport (Sea-Tac Airport). Tests were performed using either static or active nicotine monitors.

Results:Industry documents show that the tobacco industry promoted the construction of designated smoking rooms as a way to sidetrack efforts to make Lambert Airport entirely non-smoking. Nicotine vapour air monitoring in a non-smoking area of the airport, adjacent to a smoking room located in Terminal C, reveals elevated levels of ambient nicotine vapour in excess of what would be expected in a completely non-smoking environment.

Conclusions:This study shows that airport smoking rooms expose non-smokers in adjacent non-smoking areas to a significant concentration of nicotine vapour from SHS.
Adverse effects of smoke exposure on the upper airway
Authors: Samet J M
Published: February 2004

Objective:This paper reviews secondhand smoke (SHS) exposure and diseases and symptoms of the upper airway, including the sinuses. Risks to flight attendants, who were occupationally exposed until smoking was banned on all flights, are emphasised.

Data sources:A systematic database search was conducted; the US Surgeon General’s reports and other major reviews were evaluated. Literature summarised by National Research Council (NRC) reports on the airline cabin environment are included.

Study selection:A limited number of research publications on adults were identified; these are included. Many studies cited by the NRC were never published and information is taken directly from the reports.

Data extraction:Data from observational studies of cabin crews and the general public were extracted from surveys; exposure monitoring of cabin crews is reported. Data from controlled exposure studies are included; most are challenge studies using volunteers screened for sensitivity to SHS.

Data synthesis:Evidence shows that active and passive smoking cause upper airway diseases, including sinonasal and laryngeal cancers in adult active smokers. Experimental studies indicate that brief exposures to SHS result in nasal mucosa inflammation. However, direct evidence on sinusitis is limited.

Conclusions:Evidence does not show a strong connection between active smoking and sinusitis, and active smokers have substantial exposures to SHS. However, extrapolation of these studies to cabin crews needs to be cautious, as other environmental conditions may increase risk for upper airway disease and symptoms. Surveys of cabin crews, while flawed, consistently indicate high rates of upper airway symptoms.
The case of the disappearing nitrosamines: a potentially global phenomenon
Authors: Gray N , Boyle P
Published: February 2004

The cigarette usually carries in its smoke significant doses of carcinogenic tobacco specific nitrosamines (TSNAs), which have been implicated as causes of oral, lung, oesophageal, and pancreatic cancer. However, there is substantial variation in nitrosamine content of the smoke of modern cigarettes. This variation is both unacceptable and unnecessary, as TSNAs can be readily removed during the manufacturing process. Removing a known carcinogen needs no justification, even though proof of benefit may not be forthcoming for decades.
Clearing the airways: advocacy and regulation for smoke-free airlines
Authors: Holm A L , Davis R M
Published: February 2004

Objective:To examine the advocacy and regulatory history surrounding bans on smoking in commercial airliners.

Methods:Review of historical documents, popular press articles, and other sources to trace the timeline of events leading up to the US ban on smoking in airliners and subsequent efforts by airlines and other nations.

Results:In early years, efforts by flight attendants and health advocates to make commercial airliners smoke-free were not productive. Advocacy efforts between 1969 and 1984 resulted in maintenance of the status quo, with modest exceptions (creation of smoking and non-smoking sections of aircraft, and a ban on cigar and pipe smoking). Several breakthrough events in the mid 1980s, however, led to an abrupt turnaround in regulatory efforts. The first watershed event was the publication in 1986 of the National Academy of Science’s report on the airliner cabin environment, which recommended banning smoking on all commercial flights. Subsequently, following concerted lobbying efforts by health advocates, Congress passed legislation banning smoking on US domestic flights of less than two hours, which became effective in 1988. The law was made permanent and extended to flights of less than six hours in 1990. This landmark legislation propelled the adoption of similar rules internationally, both by airlines and their industry’s governing bodies. Though the tobacco industry succeeded in stalling efforts to create smoke-free airways, it was ultimately unable to muster sufficient grassroots support or scientific evidence to convince the general public or policymakers that smoking should continue to be allowed on airlines.

Conclusions:The movement to ban smoking in aircraft represents a case study in effective advocacy for smoke-free workplaces. Health advocates, with crucial assistance from flight attendants, used an incremental advocacy process to push for smoking and non-smoking sections on US commercial flights, then for smoking bans on short domestic flights, and finally for completely smoke-free domestic and international flights. Through the course of the battle, advocates from all quarters of tobacco control presented a unified message, exhibited remarkable focus on an attainable goal, and effectively leveraged their relationships with champions in both government and the private sector.
The decline of smoking in British portraiture: Table 1
Authors: Wilson N , Thomson G
Published: February 2004

Objective:To examine time trends in the portrayal of smoking in a national collection of portraiture and to compare this with the similar trends for television and film.

Methods:A compact disc produced by the National Portrait Gallery in London, UK, was systematically searched for artworks produced in the years 1950 to 1999. A “smoking portrayal” in an artwork was defined as having a cigarette, cigar or pipe in the mouth or hand of a named individual.

Results:Out of 1063 artworks included in the analysis, 53 portrayed smoking by identifiable individuals (5.0%). The rate of portrayal was highest in the 1950s (10%) and 1960s (11%) and then declined sharply thereafter (p value for trend < 0.00001). Smoking virtually disappeared from portraiture in the 1990s (at 0.6%). The median age of the smokers portrayed was significantly higher in the 1970 to 1999 period when compared to the 1950 to 1969 period.

Conclusions:The decline of smoking in this collection of portraiture is consistent with the decline in smoking in the UK over these decades, but contrasts with trends for increasing smoking portrayal described elsewhere for film and television.
Size effects in axially loaded square-section concrete prisms strengthened using carbon fibre reinforced polymer wrapping
Authors: Masia Mark J , Gale Trevor N , Shrive Nigel G
Published: February 2004

The use of carbon fibre reinforced polymer (CFRP) wrapping to strengthen plain concrete prisms of square cross section was investigated experimentally. The study was aimed at quantifying the increase in axial compressive strength and ductility that can be achieved and assessing the effect of cross-sectional size on the increases. Thirty prisms of three different square cross-sectional sizes (100 mm × 100 mm × 300 mm, 125 mm × 125 mm × 375 mm, 150 mm × 150 mm × 450 mm) were tested. Ten prisms were constructed in each size. Five prisms in each size were left unwrapped as control specimens, and five were wrapped with two layers of unidirectional CFRP laminate. All prisms were loaded in axial compression until failure. Significant increases in strength and ductility were achieved by wrapping. The effectiveness of the wrap, as measured by the percentage increases in strength and peak axial strain, reduced with increasing cross-sectional size. These tests indicate that the use of CFRP wrapping is an effective technique for strengthening and (or) rehabilitating concrete columns. Test results available in the literature by other authors are also summarized. Although these results are highly scattered, they are consistent with the findings of the current tests.Key words: concrete, prism, column, square, rehabilitation, strengthening, FRP, experimental.
Interactions between cavity flow and main stream skimming flows: an experimental study
Authors: Gonzalez C A , Chanson H
Published: February 2004

In the last two decades, research on the hydraulics of skimming flows down stepped chutes was driven by needs for better design guidelines. Skimming flows are characterized by significant momentum transfer from the main stream to the recirculation zones. Investigations are difficult because of the complex nature of the flow, the strong flow aeration, and the interactions between entrained air and turbulence. This study provides a comprehensive database on main stream and cavity flow interactions in skimming flows down a stepped chute. Measurements were conducted on a large facility (α = 15.9°, h = 0.05 and 0.1 m, W = 1 m) with precise instrumentation based upon a Froude similitude. Air–water velocity and turbulence measurements demonstrated a well-defined mixing layer developing downstream of each step edge in which the velocity profiles had the same shape as classical monophase flow results. A comparative analysis of air–water flow properties for Froude similar flow conditions showed a good agreement between the two step heights in terms of dimensionless distributions of air content, velocity, and turbulence intensity, but dimensionless bubble count rates, turbulence levels, and bubble chord sizes were improperly scaled.Key words: stepped chute, skimming flow, flow recirculation, momentum exchange, physical modelling.
Flexural and shear strengthening of timber beams using glass fibre reinforced polymer bars — an experimental investigation
Authors: Svecova D , Eden R J
Published: February 2004

An experimental program was undertaken at The University of Manitoba to test timber stringers strengthened with glass fibre reinforced polymer (GFRP) bars. Various strengthening schemes were investigated as a means of increasing the load carrying capacity of timber stringers in shear and flexure. The shear strengthening was achieved by inserting GFRP dowels in the centre of the cross section along the length of the stringers. The flexural strengthening used the concept of near-surface-mounted GFRP bars. Fifty beams were tested to evaluate the performance of the various strengthening schemes. The behaviour of the beams is described in terms of mode of failure, mechanical properties, and load–deflection behaviour. This study found that strengthening timber stringers with GFRP reinforcement increased the ultimate strength of the stringers and reduced its variability. It is believed that the shear and flexural GFRP reinforcements act as a truss member within the timber beam and bridge the local defects and discontinuities of the timber.Key words: timber, glass fibre reinforced polymer, bridge, stringers, dowels, strengthening, ductility.
Neural networks for the inversion of soil surface parameters from synthetic aperture radar satellite data
Authors: Sahebi Mahmod Reza , Bonn Ferdinand , Bénié Goze B
Published: February 2004

This paper presents an application of neural networks to the extraction of bare soil surface parameters such as roughness and soil moisture content using synthetic aperture radar (SAR) satellite data. It uses a fast learning algorithm for training a multilayer feedforward neural network using the Kalman filter technique. Two different databases (theoretical and empirical) were used for the learning stage. Each database was configured as single and multiangular sets of input data (data acquired at two different incidence angles) that are compatible with data from one and two satellite images, respectively. All the configurations are trained and then evaluated using RADARSAT-1 and simulated data. The empirical (measured) database with the multiangular set of input data configuration had the best accuracy with a mean error of 1.54 cm for root mean square (rms) height of the surface roughness and 2.45 for soil dielectric constant in the study area. Based on these results the proposed approach was applied on RADARSAT-1 images from the Chateauguay watershed area (Quebec, Canada) and the final results are presented in the form of roughness and humidity maps.Key words: neural networks, Kalman filter, RADARSAT, SAR, soil roughness, soil moisture.
Structural behaviour of water sloshing damper with embossments subject to random excitation
Authors: Ju Young-Kyu
Published: February 2004

To improve the serviceability of tall buildings, several types of vibration control systems have been developed. The tuned liquid damper (TLD) has advantages, such as simple adjustment of natural frequency, easy installation, and low maintenance. Since water tanks at the top of tall buildings can be directly modeled as a TLD system, it is more practical than any other vibration control system in Korea. Since most of the tanks in Korea have embossments on the wall, the structural characteristics are different from those of tanks used in other countries. As the damping ratio of the TLD depends on several factors, such as the magnitude and frequency of applied load, the shape of the tank, wall roughness, and so forth, it is difficult to evaluate the control performance of the tank exactly. In this study, the characteristics of the water sloshing damper with embossments (WSDE) are evaluated and the equation for equivalent damping ratio is proposed. To clarify the damping effect of a high-rise building with a damping device subject to random excitation, an experiment of a coupled structural model with a water tank was conducted. The parameters were mass ratio of water to model structure, number of wire screens, and shape factor of the water tank. The peak displacement, acceleration response, and standard deviation of the experimental results are analyzed. The coupled structural model with a water tank shows lower maximum and standard deviation responses than those of the structural model alone.Key words: water sloshing damper with embossment, vibration control, structural test, tall buildings.
Effet des imperfections géométriques sur la stabilité des coques élastiques cylindriques
Authors: Khamlichi Abdellatif , Bezzazi Mohammed , Elbakkali Larbi , Limam Ali
Published: February 2004

The effects of geometrical imperfections on the critical load of elastic cylindrical shells when subjected to axial compression are studied through analytical modelling. In addition to distributed defects of both axisymmetric or asymmetric forms, emphasis is put on the more severe case of localized defects satisfying the axial symmetry. The Von Kármán – Donnell shell equations were used. The obtained results show that shell strength at buckling varies very much with the defect amplitude. These variations are not monotonic in general. They indicate however a clear reduction of the shell critical load for some defects revealed as the most dangerous ones. The proposed method does not consider the complete coupled situation that may arise from interactions between several localized defects. It facilitates nevertheless straightforward initializing of closer analyses if such couplings are to be taken into account by means of special numerical approaches, because it enables fast a priori selection of the most hazardous isolated defects.Key words: stability, buckling, imperfections, thin shells, silos, localized defects.
Failure tests on full-scale models of grout laminated wood decks
Authors: Mufti Aftab A , Bakht Baidar , Svecova Dagmar , Limaye Vidyadhar
Published: February 2004

Grout laminated wood decks (GLWDs), representing the third generation of stressed wood decks, comprise either laminates or logs trimmed to obtain two parallel faces. The logs or laminates, running along the span, are held together by means of transverse internal grout cylinders that may be in either compression or tension. Two full-scale models of GLWD were constructed at Dalhousie University, Halifax, one with grout cylinders in compression and the other with the cylinders in tension. Service load tests conducted in Halifax showed that the former deck had better load distribution characteristics. Two years after the tests in Halifax, the models were shipped to The University of Manitoba in Winnipeg, where they were tested to failure under a central patch load. Because of miscommunication with the supplier, the logs of the GLWD with grout cylinders in compression were also trimmed to the third face that was kept at the bottom of the deck. The failure tests showed that despite its superior load distribution characteristics, the deck with grout cylinders in compression failed at a significantly lower load than the GLWD with cylinders in tension. It is argued that a planar surface in the logs at the flexural tension face not only reduces their flexural stiffness but also brings the defects of wood to the surface with maximum stress. The deck with the flat bottom surface underwent tension failure of the most heavily loaded logs, whereas the deck with the intact round surface of the logs at both top and bottom failed by horizontal splitting of all the logs.Key words: articulated plate, bridge deck, grout laminated deck, orthotropic plate, timber.
Fouling assessment in a municipal water reclamation reverse osmosis system as related to concentration factor
Authors: Xie R J , Gomez M J , Xing Y J , Klose P S
Published: February 2004

A study was conducted to assess possible formation of inorganic scaling and organic fouling in a municipal wastewater reverse osmosis (MWRO) system with microfiltration membrane treated secondary effluent as feed water. Results indicate that reject from the MWRO process can be supersaturated with sparingly soluble phosphate salts and hydroxide compounds that may form scales on the reverse osmosis (RO) membrane. The degrees of saturation, however, are much less than that in the seawater RO (SWRO) process. Therefore, a concentration factor as high as 10 can be applied to the MWRO, reflecting a recovery of 90%. Such high recovery was demonstrated using RO design software and operating a two 3-elements-in-series RO pilot plant. As the recovery rate increases, organic substances from the feed water concentrate in membrane elements at locations where flowrate is substantially reduced. At CF 5, total organic carbon and total nitrogen in the reject can be greater than 40 g/m3. The challenge of high recovery in the MWRO process then is the design and configuration of an efficient RO process in which organic and bio-fouling can be effectively controlled and advanced technologies can be integrated for fouling minimization. Key words: wastewater reclamation, reverse osmosis, membrane inorganic scaling, organic fouling, concentration factor.
Monitoring spatial and temporal variations of phosphorus within a cold climate subsurface flow constructed wetland
Authors: McCarey A E.D , Anderson B C , Martin D
Published: February 2004

Performance of constructed wetland systems has been widely variable, particularly with respect to cold climate systems. Phosphorus removal has been particularly challenging in wetland systems, with widely variable removal efficiencies being reported. A subsurface flow constructed wetland is being used at Sunny Creek Estates in Bayside, Ontario, to polish sewage lagoon effluent. A benchmarking study was conducted to gather operational data from within the wetland, to characterize phosphorus dynamics within the system. Samples were collected and analyzed for total and dissolved phosphorus concentrations for a one-year period. Spatial and temporal variations in phosphorus were then investigated, and mass balances were performed. Mass balances conducted on an average annual basis, and on a seasonal basis, indicated a net removal of phosphorus in all cases except the spring season. Segmented phosphorus profiles through the wetland revealed that, regardless of season, there is more phosphorus in shallower wells, and with increasing distance from the influent distribution pipe. Phosphorus masses varied significantly with depth, and in directions both parallel and perpendicular to flow through the wetland. The seasonal and spatial variations illustrate the importance of monitoring within wetlands, and reinforce the limitations of using a black box approach in wetland design. Key words: constructed treatment wetlands, subsurface flow, wastewater treatment, phosphorus, cold-climate operation, eutrophication, seasonal variability.
Developments in the use ofBacillusspecies for industrial production
Authors: Schallmey Marcus , Singh Ajay , Ward Owen P
Published: February 2004

Bacillus species continue to be dominant bacterial workhorses in microbial fermentations. Bacillus subtilis (natto) is the key microbial participant in the ongoing production of the soya-based traditional natto fermentation, and some Bacillus species are on the Food and Drug Administration's GRAS (generally regarded as safe) list. The capacity of selected Bacillus strains to produce and secrete large quantities (20–25 g/L) of extracellular enzymes has placed them among the most important industrial enzyme producers. The ability of different species to ferment in the acid, neutral, and alkaline pH ranges, combined with the presence of thermophiles in the genus, has lead to the development of a variety of new commercial enzyme products with the desired temperature, pH activity, and stability properties to address a variety of specific applications. Classical mutation and (or) selection techniques, together with advanced cloning and protein engineering strategies, have been exploited to develop these products. Efforts to produce and secrete high yields of foreign recombinant proteins in Bacillus hosts initially appeared to be hampered by the degradation of the products by the host proteases. Recent studies have revealed that the slow folding of heterologous proteins at the membrane – cell wall interface of Gram-positive bacteria renders them vulnerable to attack by wall-associated proteases. In addition, the presence of thiol-disulphide oxidoreductases in B. subtilis may be beneficial in the secretion of disulphide-bond-containing proteins. Such developments from our understanding of the complex protein translocation machinery of Gram-positive bacteria should allow the resolution of current secretion challenges and make Bacillus species preeminent hosts for heterologous protein production. Bacillus strains have also been developed and engineered as industrial producers of nucleotides, the vitamin riboflavin, the flavor agent ribose, and the supplement poly-γ-glutamic acid. With the recent characterization of the genome of B. subtilis 168 and of some related strains, Bacillus species are poised to become the preferred hosts for the production of many new and improved products as we move through the genomic and proteomic era.Key words: Bacillus, fermentation, enzymes, insecticides, vitamins, antibiotics, D-ribose.
Influence of phosphate and disinfection on the composition of biofilms produced from drinking water, as measured by fluorescence in situ hybridization
Authors: Batté M , Mathieu L , Laurent P , Prévost M
Published: February 2004

Biofilms were grown in annular reactors supplied with drinking water enriched with 235 µg C/L. Changes in the biofilms with ageing, disinfection, and phosphate treatment were monitored using fluorescence in situ hybridization. EUB338, BET42a, GAM42a, and ALF1b probes were used to target most bacteria and the alpha (α), beta (β), and gamma (γ) subclasses of Proteobacteria, respectively. The stability of biofilm composition was checked after the onset of colonization between T = 42 days and T = 113 days. From 56.0% to 75.9% of the cells detected through total direct counts with DAPI (4'-6-diamidino-2-phenylindole) were also detected with the EUB338 probe, which targets the 16S rRNA of most bacteria. Among these cells, 16.9%–24.7% were targeted with the BET42a probe, 1.8%–18.3% with the ALF1b probe, and <2.5% with the GAM42a probe. Phosphate treatment induced a significant enhancement to the proportion of γ-Proteobacteria (detected with the GAM42a probe), a group that contains many health-related bacteria. Disinfection with monochloramine for 1 month or chlorine for 3 days induced a reduction in the percentage of DAPI-stained cells that hybridized with the EUB338 probe (as expressed by percentages of EUB338 counts/DAPI) and with any of the ALF1b, BET42a, and GAM42a probes. The percentage of cells detected by any of the three probes (ALF1b+BET42a+GAM42a) tended to decrease, and reached in total less than 30% of the EUB338-hybridized cells. Disinfection with chlorine for 7 days induced a reverse shift; an increase in the percentage of EUB338 counts targeted by any of these three probes was noted, which reached up to 87%. However, it should be noted that the global bacterial densities (heterotrophic plate counts and total direct counts) tended to decrease over the duration of the experiment. Therefore, those bacteria that could be considered to resist 7 days of chlorination constituted a small part of the initial biofilm community, up to the point at which the other bacterial groups were destroyed by chlorination. The results suggest that there were variations in the kinetics of inactivation by disinfectant, depending on the bacterial populations involved.Key words: biofilm, phosphate, chlorine, monochloramine, FISH, drinking water.
Controlled induction of the RpoS regulon inEscherichia coli, using an RpoS-expressing plasmid
Authors: Chen Guozhu , Schellhorn Herb E
Published: February 2004

RpoS, an alternative sigma factor produced by many Gram-negative bacteria, primarily controls genes that are expressed in stationary phase in response to nutrient deprivation. To test the idea that induction of RpoS in the exponential phase, when RpoS is not normally expressed, increases RpoS-dependent gene expression, we constructed a plasmid carrying the rpoS gene under the control of an IPTG (isopropyl-β-D-thiogalactopyranoside)-inducible T7lac promoter. Northern and Western analyses revealed that levels of RpoS mRNA and protein, respectively, increased in response to the inducer IPTG. Assays of changes in RpoS-dependent functions (catalase activity and glycogen accumulation), confirmed that induced RpoS was functional in exponential phase and was sufficient for the expression of RpoS-dependent functions. Controlled expression of RpoS and RpoS-dependent genes by plasmid-encoded rpoS may thus offer a useful tool for the study of RpoS-dependent gene expression.Key words: RpoS, regulon, gene expression, Escherichia coli.
Extracellular peroxidase production by Coprinus species from urea-treated soil
Authors: Ikehata Keisuke , Buchanan Ian D , Smith Daniel W
Published: February 2004

Thirteen strains of inky-cap mushroom Coprinus species were evaluated for the production of extracellular peroxidase. The liquid fermentation was carried out in shake flasks containing 1% glucose, 0.5% peptone, 0.3% yeast extract, and 0.3% malt extract broth at 25 °C. Peroxidase activity was detected in the liquid culture of several Coprinus species, including C. echinosporus NBRC 30630; C. macrocephalus NBRC 30117; Coprinus spp. UAMH 10065, UAMH 10066, UAMH 10067, and 074, after 10 days of growth. Peroxidase production by Coprinus sp. UAMH 10067, a Coprinus species isolated from urea-treated soil, was comparable to that of C. cinereus and reached 15 U·mL–1 after 10 days. In addition, the peroxidase from Coprinus sp. UAMH 10067 was apparently more thermally stable than the enzyme produced by C. cinereus.Key words: Coprinus species, urea treatment, phenol, wastewater treatment.
Potential role of kinins in the effects of taurine in high-fructose-fed rats
Authors: Nandhini A.T Anitha , Thirunavukkarasu V , Anuradha C V
Published: February 2004

The present work investigates the involvement of kinins in the effects of taurine in fructose-fed hypertensive rats. The effects of taurine on blood pressure, plasma glucose, insulin, and the insulin sensitivity index were determined. Angiotensin-converting enzyme (ACE) activity and nitrite content in plasma, plasma and tissue kallikrein activity, and taurine content were also investigated. The blood pressure changes in response to the coadministration of inhib itors of the synthesis of nitric oxide (NO), prostaglandins (PGs), or a kinin receptor blocker along with taurine was also evaluated. Fructose-fed rats had higher blood pressure and elevated plasma levels of glucose and insulin. Kallikrein activity, taurine, and nitrite contents were significantly lower in fructose-fed rats as compared with controls. The increases in systolic blood pressure, hyperglycemia, and hyperinsulinemia were controlled by taurine administration in fructose-fed rats. ACE activity was lower, while nitrite and taurine content and kallikrein activity were higher, in taurine-supplemented rats as compared with fructose-fed rats. A significant increase in blood pressure was observed in rats cotreated with the inhibitors Hoe 140 (a kinin receptor blocker), L-NAME (a NO synthase inhibitor), or indo metha cin (a PG synthesis inhibitor) with taurine for 1 week as compared with taurine-treated fructose-fed rats. This suggests that the antihypertensive effect of taurine in fructose-fed rats was blocked by the inhibitors. Augmented kallikrein activity and, hence, increased kinin availability may be implicated in the effects of taurine in fructose-fed hypertensive rats.Key words: kallikrein, nitric oxide, angiotensin-converting enzyme, blood pressure, taurine.
Human urotensin-II enhances plasma extravasation in specific vascular districts in Wistar rats
Authors: Gendron Gabrielle , Simard Bryan , Gobeil, Jr. Fernand , Sirois Pierre , D'Orléans-Juste Pedro , Regoli Domenico
Published: February 2004

Plasma extravasation (PE) was measured in adult Wistar rats by injecting Evans blue dye (EB) (20 mg kg–1) intravenously in the absence or presence of human urotensin II (U-II) (0.1–10 nmol kg–1). A consistent increase of PE was observed in specific organs (e.g., aorta, from 28.1 ± 2.4 to 74.6 ± 3.6 µg EB g–1 dry tissue; P < 0.001) after an administration of 4.0 nmol kg–1 (a preselected optimal dose) of U-II. The effects of U-II (4.0 nmol kg–1) were compared with those of endothelin-1 (ET-1) (1.0 nmol kg–1). In the thoracic aorta and pancreas, U-II was active, while ET-1 was not. The two agents were equivalent in the heart and kidney, whereas, in the duodenum, ET-1 was more active than U-II. Increases of plasma extravasation induced by U-II, but not by ET-1, were reduced after treatment with [Orn8]U-II (0.3 µmol kg–1). This latter antagonist did not show any significant residual agonistic activity in vivo in the rat. Other specific receptor antagonists for ET-1, such as BQ-123 (endothelin type A (ETA) receptor) and BQ-788 (endothelin type B (ETB) receptor), and for the platelet activating factor (PAF), such as BN50730, failed to modify the action of U-II. The present study is the first report describing the modulator roles of U-II on vascular permeability in specific organs. Moreover, the action of U-II appears specific, since it is independent of the ET-1 and PAF signalling pathways.Key words: urotensin-II, receptors antagonists, Evans blue dye, vascular permeability, rats.
Attenuation of liver ischemia-reperfusion-induced atrial dysfunction by external pacing but not by isoproterenol
Authors: Ben-Abraham Ron , Shapira Itzhak , Szold Amiki , Weinbroum Avi A
Published: February 2004

Remote ischemia–reperfusion detrimentally affects myocardial function by initially interfering with the rate of contraction. We investigated the usefulness of isoproterenol versus external electrical pacing in attenuating secondary functional damage of isolated Wistar rat atria. Atrial strips (n = 10/group) were bathed within oxygenated Krebs–Henseleit solution that exited from isolated livers that had been either perfused normally (controls) or underwent no flow (ischemia) for 2 h. In addition to one noninterventional ischemia-exposed strip group, a second group was externally paced at a fixed rate (55 pulses·min–1, 6 V) and a third "ischemia" group was treated with isoproterenol (0.1 mM), both interventions commencing upon the strips' exposure to the hepatic effluents. Control strips displayed unaltered contraction rate and systolic-generated tension during the 2-h exposure. Nontreated strips exposed to ischemic reperfusate experienced bradycardia compared with baseline values (7 ± 2 vs. 50 ± 12 beats·min–1, p < 0.05), followed <1-min later by a fall in the generated tension (11 ± 4 vs. 20 ± 6 mmHg, p < 0.05). The paced-ischemic strips displayed unaltered rate and force of contraction, whereas the addition of isoproterenol did not prevent deterioration in the rate and force of contraction (8 ± 3 beats·min–1, 12 ± 4 mmHg, respectively; p < 0.05 vs. baseline control ischemia-paced strips). Thus, external electrical pacing prevented liver ischemia–reperfusion-induced atrial strips' bradycardia and loss of contractility, while isoproterenol did not.Key words: ischemia, reperfusion, liver, atrium, dysfunction, isoproterenol, pacing.
Phylogenetic relationships of the genusChiropterotriton(Caudata: Plethodontidae) based on 16S ribosomal mtDNA
Authors: Parra-Olea Gabriela
Published: February 2004

The genus Chiropterotriton contains only 12 described species but includes a rich variety of morphological and ecological forms ranging from diminutive to large cave-dwelling species, as well as a number of terrestrial and arboreal forms. Although morphological diversification has taken place during the evolution of this genus, morphological stasis and parallelism also characterize the evolution of this group, generating complexes of cryptic species. I obtained sequences of the 16S ribosomal mtDNA gene from most of the species. Mitochondrial DNA shows great diversification, with genetic divergence among taxa as high as 12.5%. The 531-bp mtDNA data matrix contained 121 parsimony-informative characters. Basal relationships are poorly supported by maximum parsimony analyses. There is, however, support for a clade that includes all of the samples of the C. chiropterus group. The maximum-likelihood and Bayesian topologies differ from maximum-parsimony topologies mainly in the arrangement of the basal relationships. Based on the results, the genus Chiropterotriton comprises 12 species with available names: C. arboreus, C. chiropterus, C. chondrostega, C. cracens, C. dimidiatus, C. lavae, C. magnipes, C. mosaueri, C. multidentatus, C. orculus, C. priscus, and C. terrestris, plus 7 additional undescribed species for which allozyme and mitochondrial data sets are congruent.