bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation of the Intact Zwittermicin A Biosynthetic Gene Cluster and Discovery of a Complementary Resistance Mechanism in Bacillus thuringiensis
Authors: Luo Yi , Ruan Li-Fang , Zhao Chang-Ming , Wang Cheng-Xian , Peng Dong-Hai , Sun Ming 
Published: July 2011

ABSTRACT

Zwittermicin A (ZmA) is a hybrid polyketide-nonribosomal peptide produced by certain
Bacillus cereus
group strains. It displays broad-spectrum antimicrobial activity. Its biosynthetic pathway in
B. cereus
has been proposed through analysis of the nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) modules involved in ZmA biosynthesis. In this study, we constructed a bacterial artificial chromosome (BAC) library from
Bacillus thuringiensis
subsp.
kurstaki
strain YBT-1520 genomic DNA. The presence of known genes involved in the biosynthesis of ZmA in this BAC library was investigated by PCR techniques. Nine positive clones were identified, two of which (covering an approximately 60-kb region) could confer ZmA biosynthesis ability upon
B. thuringiensis
BMB171 after simultaneous transfer into this host by two compatible shuttle BAC vectors. Another previously unidentified gene cluster, named
zmaWXY
, was found to improve the yield of ZmA and was experimentally defined to function as a ZmA resistance transporter which expels ZmA from the cells. Putative transposase genes were detected on the flanking regions of the two gene clusters (the ZmA synthetic cluster and
zmaWXY
), which suggests a mobile nature of these two gene clusters. The intact ZmA gene cluster was validated, and a resistance mechanism complementary to that for
zmaR
(the previously identified ZmA self-resistance gene) was revealed. This study also provided a straightforward strategy to isolate and identify a huge gene cluster from
Bacillus
.
Comparison of the characteristics of fire and non-fire households in the 2004–2005 survey of fire department-attended and unattended fires
Authors: Greene Michael A 
Published: July 2011

ObjectiveComparison of characteristics of fire with non-fire households to determine factors differentially associated with fire households (fire risk factors).Design, setting and subjectsNational household telephone survey in 2004–2005 by the US Consumer Product Safety Commission with 916 fire households and a comparison sample of 2161 non-fire households. There were an estimated 7.4 million fires (96.6% not reported to fire departments) with 130 000 injuries.Main outcome measureBivariate analysis and multivariate logistic regression analyses to assess differences in household characteristics.ResultsSignificant factors associated with fire households were renting vs. owning (OR 1.988 p<0.0001); household members under 18 year of age (OR 1.277 p<0.0001); lack of residents over 64 years old (OR 0.552 p=0.0007); and college or higher education (some college OR 1.444 p=0.0360, college graduate OR 1.873, p<0.0001, postgraduate OR 2.156 p<0.0001). Not significant were age of house; race; ethnicity; and income. Number of smokers was borderline significant (OR 1.132 p=0.1019) but was significant in the subset of fire households with non-cooking fires (OR 1.383 p=0.0011). Single family houses were associated with non-fire households in the bivariate analysis but not in the multivariate analyses.ConclusionRenting, household members under 18 years old and smokers are risk factors for unattended fires, similar to the literature for fatal and injury fires. Differences included household members over 65 years old (associated with non-fire households), college/postgraduate education (associated with fire households) and lack of significance of income. Preventing cooking fires (64% of survey incidents), smoking prevention efforts and fire prevention education for families with young children have the potential for reducing unattended fires and injuries.
The Energy Budget of the Polar Atmosphere in MERRA
Authors: Cullather Richard I. , Bosilovich Michael G. 
Published: July 2011

Abstract
Components of the atmospheric energy budget from the Modern-Era Retrospective Analysis for Research and Applications (MERRA) are evaluated in polar regions for the period 1979–2005 and compared with previous estimates, in situ observations, and contemporary reanalyses. Closure of the budget is reflected by the analysis increments term, which indicates an energy surplus of 11 W m−2 over the North Polar cap (70°–90°N) and 22 W m−2 over the South Polar cap (70°–90°S). Total atmospheric energy convergence from MERRA compares favorably with previous studies for northern high latitudes but exceeds the available previous estimate for the South Polar cap by 46%. Discrepancies with the Southern Hemisphere energy transport are largest in autumn and may be related to differences in topography with earlier reanalyses. For the Arctic, differences between MERRA and other sources in top of atmosphere (TOA) and surface radiative fluxes are largest in May. These differences are concurrent with the largest discrepancies between MERRA parameterized and observed surface albedo. For May, in situ observations of the upwelling shortwave flux in the Arctic are 80 W m−2 larger than MERRA, while the MERRA downwelling longwave flux is underestimated by 12 W m−2 throughout the year. Over grounded ice sheets, the annual mean net surface energy flux in MERRA is erroneously nonzero. Contemporary reanalyses from the Climate Forecast Center (CFSR) and the Interim Re-Analyses of the European Centre for Medium-Range Weather Forecasts (ERA-I) are found to have better surface parameterizations; however, these reanalyses also disagree with observed surface and TOA energy fluxes. Discrepancies among available reanalyses underscore the challenge of reproducing credible estimates of the atmospheric energy budget in polar regions.
Restoring Point‐of‐Care Testing during Parathyroidectomy with a Newer Parathyroid Hormone Assay
Authors: Terris David J. , Weinberger Paul M. , Farrag Tarik , Seybt Melanie , Oliver Joyce E. 
Published: July 2011

ObjectiveIntraoperative parathyroid hormone (IOPTH) monitoring has emerged as a useful adjunct in parathyroidectomy. Originally performed within the operating room, removal of the Nichols assay from the market forced many surgeons to rely on testing done in central laboratories, reducing convenience and prolonging operative times. The authors hypothesized that PTH assessment with a newer point‐of‐care (POC) assay would reduce results reporting time compared with central‐laboratory PTH assays.Study DesignCross‐sectional study with planned data collection.SettingAcademic medical center.Subjects and MethodsPatients underwent parathyroidectomy for primary or recurrent hyperparathyroidism. Intraoperative monitoring of serum PTH levels was used to confirm biochemical cure following adenoma excision. Samples were run in duplicate using both a POC PTH assay (Future Diagnostics) located within the operating room and a laboratory‐based assay (Turbo PTH). Samples were taken at incision and at 5‐, 10‐, and 15‐minute intervals following removal of suspected parathyroid adenomas. Results reporting time was recorded and compared by nonparametric Wilcoxon rank sum test.ResultsSixty‐six serum samples were assayed. There was excellent correlation between POC and central‐laboratory IOPTH results (r = 0.880, P <. 001). The POC IOPTH results were available faster than corresponding central‐laboratory results, with a mean of 14.4 minutes compared with 30.7 minutes, respectively (P <. 001). All patients (100%) demonstrated a biochemical cure by the end of the procedure.ConclusionUse of a rapid POC IOPTH assay results in a significant decrease in the amount of time for laboratory results to be communicated to the surgical team. This reduces operative times for parathyroidectomy and improves patient care.
Ethics
Authors: Healy Gerald B. 
Published: July 2011

Dr John J. Conley was an integral part of the house of surgery in the latter part of the 20th century. Conley placed the ethical values of practice at the forefront of his teachings and transcribed many valuable lessons in his writings. In 1993, he wrote his version of the Hippocratic Oath outlining 12 important principles. Those principles are revisited here as a way to celebrate the joy of the calling that is medical practice. In addition, 7 new elements are added as a way to enhance that joy in the light of 21st‐century medicine. The uplifting experience found in a career filled with ethical conduct is the legacy we should all strive to achieve.
Comparison of the use of minimized cardiopulmonary bypass with conventional techniques on the incidence of retinal microemboli during aortic valve replacement surgery
Authors: Rimpiläinen R , Hautala N , Koskenkari JK , Rimpiläinen J , Ohtonen PP , Mustonen P , Surcel H-M , Savolainen E-R , Mosorin M , Ala-Kokko TI , Juvonen T 
Published: July 2011

Objectives: Minimized cardiopulmonary bypass (MCPB) circuits have been shown to reduce cerebral and retinal microembolisation during coronary artery bypass graft (CABG) surgery compared to conventional CPB (CCPB) circuits. Our aim was to evaluate whether the reduction of microembolisation is sustained in aortic valve surgery, as well as to evaluate the effects of MCPB on inflammatory, endothelial, and platelet activation markers. Material and methods: Patients were randomized to undergo aortic valve replacement (AVR), with or without CABG, with MPCB (n=20) or CCPB (n=20). After anaesthesia induction and termination of CPB, standardized digital retinal fluorescein angiography images were obtained on both eyes and analyzed in a blinded fashion. Blood samples were collected at eight time points until the third postoperative day. Results: Fewer patients in the MCPB group showed evidence of microembolic perfusion defects on postperfusion retinal fluorescein angiographs compared to the CCPB group (37% vs. 63%, absolute difference 26%, 95% CI -5% -51%, P = 0.194). Polymorphonuclear leukocyte (PMN) elastase and von Willebrand factor release were statistically significantly reduced in the MCPB group, but there were no significant differences in other markers of inflammation, coagulation or endothelial activation. A significantly higher three-fold increase in the amount of shed blood was collected to the cell saver with a higher rate of intraoperative platelet transfusion in the MCPB group compared to CCPB. Conclusions: The use of MCPB was associated statistically insignificantly with less retinal microemboli compared to CCPB. MCPB was complicated by excess bleeding and need for transfusion. The feasibility of MCPB techniques in valve surgery requires further studies.
Usefulness of the 6-minute walk test and the 200-metre fast walk test to individualize high intensity interval and continuous exercise training in coronary artery disease patients after acute coronary syndrome: a pilot controlled clinical study
Authors: Gremeaux M , Hannequin A , Laurent Y , Laroche D , Casillas JM , Gremeaux V 
Published: July 2011

Objective: To study the effects of three individualized exercise training prescriptions using either a percentage of maximal heart rate (HR), maximal 6-minute walk test (6MWT) HR, or maximal 200-metre fast walk test (200-mFWT) HR, on walking performance and exercise capacity in coronary artery disease (CAD) patients. Design: Controlled clinical study. Participants: Twenty-seven outpatients enrolled in a rehabilitation programme after an acute coronary syndrome. Setting: Cardiac rehabilitation unit. Interventions: Three groups: (A): moderate intensity continuous exercise (MICE) at 70% of the maximal HR of the graded maximal exercise test ( n = 10); (B): MICE at the maximal 6MWT HR ( n = 8); (C): high intensity interval training (HIIT) based on the 6MWT and the 200-mFWT maximal HR ( n = 9). Group B and C performed walk tests every 2 weeks, to readjust training HR (THR) if needed. Measures: 6MWT and 200-mFWT performances, peak VO2 and peak power (Pmax). Results: 6MWT and 200-mFWT performances improved significantly and similarly in all groups ( P < 0.05). Peak VO2 improved significantly in all groups ( P < 0.05), this improvement being higher in group C (HIIT) versus A ( P < 0.05). Group B was closer to the recommended THR during exercise sessions compared to group A. Conclusion: This pilot study showed that using the 6MWT and 200-mFWT HR to individualize MICE or HIIT prescription is feasible in CAD patients, and could lead them closer to THR objective, to similar improvements in walking performance, and greater peak VO2 increase for HIIT. Future randomised studies should investigate long-term effects of programmes prescribed from walk tests HR, especially for HIIT modality.
Stiffness and strength aspects in the design of automotive coil springs for McPherson front suspensions: a case study
Authors: Bartolozzi R , Frendo F 
Published: July 2011

The current paper deals with the elastic and stress analysis of a side-load spring, which is employed in cars belonging to the medium segment of the European automotive market. In the design of this kind of spring both the elastic characteristics and the fatigue strength have to be considered as significant aspects. Side-load springs, indeed, have a thrust axis which results in skew with respect to the damper axis; for this reason they are widely employed in front McPherson automotive suspensions in order to minimize the side force acting on the strut damper, which is responsible for the undesired damper-sticking phenomenon. In addition to this particular elastic property, as a consequence of the research effort in reducing the mass of components typical of the automotive industry, these springs have to face very high working stresses. The structural reliability of the spring must therefore be ensured by high residual stresses, which are induced by presetting and shot peening treatment at the end of the manufacturing process. The evolution of the thrust axis during suspension travel was analysed by a finite element (FE) model of the spring–seats assembly, built starting from a three-dimensional (3D) scan of the spring. In addition an experimental campaign was planned in order to measure the residual stresses at several points along the spring by X-ray diffraction. The actual stresses were then obtained as the superposition of those produced by the external loads, computed by means of the FE model, and the measured residual stresses. The beneficial effect of residual stresses on the structural reliability is discussed with a theoretical fatigue analysis on the basis of different multiaxial criteria. A mechanism of residual stress generation, based on the superposition of stresses coming from presetting and shot peening, is also suggested with the aid of FE simulations.
Modelling of passive ammonia selective catalytic reduction system for lean-burn spark ignition direct injection engines
Authors: Narayanaswamy K , Najt P M , Li W , Perry K L , Kim C H 
Published: July 2011

Lean-burn spark ignition direct injection (SIDI) engines offer potential fuel economy savings; however, the lack of simple and cost-effective lean nitrogen oxide (NO x) aftertreatment systems hinder their broad application. Lean NO x traps (LNT) and urea selective catalytic reduction (SCR) catalysts have been widely investigated as possible lean gasoline aftertreatment technologies, but with limited acceptance. Passive ammonia SCR operation is a promising low-cost alternative for lean NO x aftertreatment with SIDI engines. The aftertreatment system includes close-coupled three-way catalyst (TWC) converters and one or more under-floor SCR catalysts. Ammonia (NH3) is formed on the TWC with short pulses of rich engine operations and the generated NH3 is then stored on the under-floor SCR catalysts. During subsequent lean operations, the NO x that breaks through the TWC converters is reduced to nitrogen by NH3 stored on the SCR catalysts. This paper provides an overview of system level analysis as a complement to experimental testing in the development of a passive NH3 SCR-based aftertreatment system. Various aftertreatment architectures (SCR type, the order, and location of the catalysts) were efficiently evaluated and screened, to achieve the best trade-off between engine back-pressure, catalyst warm-up, emission constraints, and acceptable thermal ageing under high-speed/load conditions.
A multi-zone combustion model with detailed chemistry including cycle-to-cycle dynamics for diesel engine control design
Authors: Jochim B , Felsch C , Drews P , Vanegas A , Hoffmann K , Abel D , Peters N , Pitsch H 
Published: July 2011

This paper reviews the research activities within the subproject B1 Model Reduction for Low-Temperature Combustion Processes through CFD-Simulations and Multi-Zone Models of the Collaborative Research Centre SFB 686 – Model-Based Control of Homogenized Low-Temperature Combustion. The SFB 686 is carried out at RWTH Aachen University, Germany and Bielefeld University, Germany, and is funded by the German Research Foundation (DFG). This paper thereby summarizes the outcome of various publications by the authors, with the appropriate references given in the individual sections. Additionally, some new results are introduced. The particular subject of this work is a dynamic simulation strategy for premixed charge compression ignition (PCCI) combustion that can be used in closed-loop control development. A detailed multi-zone chemistry model for the high-pressure part of the engine cycle is extended by a mean value gas exchange model accounting for the low-pressure part. Thus, an efficient model capable of describing PCCI combustion is sufficiently well established. In order to capture cycle-to-cycle dynamics, identified system dynamics influencing the input parameters are incorporated. For this, a Wiener model is set up that uses the combustion model as a nonlinear system representation. In this way, a dynamic nonlinear model for the representation of the controlled plant Diesel engine is created. The model is validated against transient experimental engine data.
How to use marginal structural models in randomized trials to estimate the natural direct and indirect effects of therapies mediated by causal intermediates
Authors: Oba Koji , Sato Tosiya , Ogihara Toshio , Saruta Takao , Nakao Kazuwa 
Published: July 2011

Background Although intention-to-treat analysis is a standard approach, additional supplemental analyses are often required to evaluate the biological relationship among interventions, intermediates, and outcomes. Therefore, we need to evaluate whether the effect of an intervention on a particular outcome is mediated by a hypothesized intermediate variable. Purpose To evaluate the size of the direct effect in the total effect, we applied the marginal structural model to estimate the average natural direct and indirect effects in a large-scale randomized controlled trial (RCT). Method The average natural direct effect is defined as the difference in the probability of a counterfactual outcome between the experimental and control arms, with the intermediate set to what it would have been, had the intervention been a control treatment. We considered two marginal structural models to estimate the average natural direct and indirect effects introduced by VanderWeele ( Epidemiology 2009) and applied them in a large-scale RCT – the Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J trial) – that compared angiotensin receptor blockers and calcium-channel blockers in high-risk hypertensive patients. Results There were no strong blood pressure-independent or dependent effects; however, a systolic blood pressure reduction of about 1.9 mmHg suppressed all events. Compared to the blood pressure-independent effects of calcium channel blockers, those of angiotensin receptor blockers contributed positively to cardiovascular and cardiac events, but negatively to cerebrovascular events. Limitations There is a particular condition for estimating the average natural direct effect. It is impossible to check whether this condition is satisfied with the available data. Conclusion We estimated the average natural direct and indirect effects through the achieved systolic blood pressure in the CASE-J trial. This first application of estimating the average natural effects in an RCT can be useful for obtaining an in-depth understanding of the results and further development of similar interventions.
Protein functional links in Trypanosoma brucei, identified by gene fusion analysis
Authors: Dimitriadis Dimitris , Koumandou V Lila , Trimpalis Philip , Kossida Sophia 
Published: July 2011

Abstract

Background
Domain or gene fusion analysis is a bioinformatics method for detecting gene fusions in one organism by comparing its genome to that of other organisms. The occurrence of gene fusions suggests that the two original genes that participated in the fusion are functionally linked, i.e. their gene products interact either as part of a multi-subunit protein complex, or in a metabolic pathway. Gene fusion analysis has been used to identify protein functional links in prokaryotes as well as in eukaryotic model organisms, such as yeast and Drosophila.

Results
In this study we have extended this approach to include a number of recently sequenced protists, four of which are pathogenic, to identify fusion linked proteins in Trypanosoma brucei, the causative agent of African sleeping sickness. We have also examined the evolution of the gene fusion events identified, to determine whether they can be attributed to fusion or fission, by looking at the conservation of the fused genes and of the individual component genes across the major eukaryotic and prokaryotic lineages. We find relatively limited occurrence of gene fusions/fissions within the protist lineages examined. Our results point to two trypanosome-specific gene fissions, which have recently been experimentally confirmed, one fusion involving proteins involved in the same metabolic pathway, as well as two novel putative functional links between fusion-linked protein pairs.

Conclusions
This is the first study of protein functional links in T. brucei identified by gene fusion analysis. We have used strict thresholds and only discuss results which are highly likely to be genuine and which either have already been or can be experimentally verified. We discuss the possible impact of the identification of these novel putative protein-protein interactions, to the development of new trypanosome therapeutic drugs.
Neural correlates of cognitive impairment in
schizophrenia
Authors: Ortiz-Gil Jordi , Pomarol-Clotet Edith , Salvador Raymond , Canales-Rodríguez Erick J. , Sarró Salvador , Gomar Jesús J. , Guerrero Amalia , Sans-Sansa Bibiana , Capdevila Antoni , Junqué Carme , McKenna Peter J. 
Published: July 2011

BackgroundCognitive impairment is an established feature of schizophrenia. However,
little is known about its relationship to the structural and functional
brain abnormalities that characterise the disorder.AimsTo identify structural and/or functional brain abnormalities associated
with schizophrenic cognitive impairment.MethodWe carried out structural magnetic resonance imaging (MRI) and
voxel-based morphometry in 26 participants who were cognitively impaired
and 23 who were cognitively preserved, all with schizophrenia, plus 39
matched controls. Nineteen of those who were cognitively impaired and 18
of those who were cognitively preserved plus 34 controls also underwent
functional MRI during performance of a working memory task.ResultsNo differences were found between the participants who were cognitively
intact and those who were cognitively impaired in lateral ventricular
volume or whole brain volume. Voxel-based morphometry also failed to
reveal clusters of significant difference in grey and white matter volume
between these two groups. However, during performance of the n-back task,
the participants who were cognitively impaired showed hypoactivation
compared with those who were cognitively intact in the dorsolateral
prefrontal cortex among other brain regions.ConclusionsCognitive impairment in schizophrenia is not a function of the structural
brain abnormality that accompanies the disorder but has correlates in
altered brain function.