bluuebunny/crossref_metadata_2025_split huggingface dataset:
The multiplicity of divergence mechanisms in a single evolving population
Authors: Maharjan Ram P , Ferenci Thomas , Reeves Peter R , Li Yang , Liu Bin , Wang Lei 
Published: June 2012

Abstract
Background
Evolutionary divergence is common within bacterial species and populations, even during a single bacterial infection. We use large-scale genomic and phenotypic analysis to identify the extent of diversification in controlled experimental populations and apply these data to differentiate between several potential mechanisms of evolutionary divergence.

Results
We defined testable differences between five proposed mechanisms and used experimental evolution studies to follow eight glucose-limited Escherichia coli chemostat populations at two growth rates. Simple phenotypic tests identified 11 phenotype combinations evolving under glucose limitation. Each evolved population exhibited 3 to 5 different combinations of the 11 phenotypic clusters. Genome sequencing of a representative of each phenotypic cluster from each population identified 193 mutations in 48 isolates. Only two of the 48 strains had evolved identically. Convergent paths to the same phenotype occurred, but two pleiotropic mutations were unique to slow-growing bacteria, permitting them greater phenotypic variance. Indeed, greater diversity arose in slower-growing, more stressed cultures. Mutation accumulation, hypermutator presence and fitness mechanisms varied between and within populations, with the evolved fitness considerably more uniform with fast growth cultures. Negative frequency-dependent fitness was shown by a subset of isolates.

Conclusions
Evolutionary diversity is unlikely to be explained by any one of the available mechanisms. For a large population as used in this study, our results suggest that multiple mechanisms contribute to the mix of phenotypes and evolved fitness types in a diversifying population. Another major conclusion is that the capacity of a population to diversify is a function of growth rate.
Developmental stress has sex-specific effects on nestling growth and adult metabolic rates but no effect on adult body size or body composition in song sparrows
Authors: Schmidt Kim L. , MacDougall-Shackleton Elizabeth A. , MacDougall-Shackleton Scott A. 
Published: June 2012

Summary
Variation in the pre- and postnatal environments can have long-term effects on adult phenotype. In humans and other animals, exposure to stressors can lead to long-term changes in physiology. These changes may predispose individuals to disease, especially disorders involving energy metabolism. In addition, by permanently altering metabolic rates and energy requirements, such effects could have important fitness consequences. We determined the effects of early-life food restriction and corticosterone (CORT) treatment on growth and adult body size, body composition (assessed via quantitative magnetic resonance), and metabolic rates in a songbird, the song sparrow (Melospiza melodia). Nestlings were hand-raised in captivity from 3 days of age (d3). Treatments (ad libitum food, food restriction, or CORT-treatment) lasted from d7–d60. Both experimental treatments had sex-specific effects on growth. In the nestling period, CORT-treated males weighed more than controls, whereas CORT-treated females weighed less than controls. Food-restricted males weighed the same as controls, whereas food-restricted females weighed less than controls. Both experimental treatments also had sex-specific effects on standard metabolic rates (SMR). Females exposed to food restriction or CORT treatment during development had higher SMRs in adulthood than control females, but neither stressor affected SMR in males. There were no effects of either treatment on adult body size, body composition (lean or fat mass), or peak metabolic rates. Therefore early-life stress may have sex-specific programming effects on metabolic rates and energy expenditure in song sparrows. In addition, both treatments affected nestling growth in a manner that exaggerated the typical sex difference in nestling mass, which could provide male nestlings with a competitive advantage over their sisters when developing in a poor quality environment.
Vector-based and landmark-guided navigation in desert ants of the same species inhabiting landmark-free and landmark-rich environments
Authors: Cheng Ken , Middleton Eliza J.T. , Wehner Rüdiger 
Published: June 2012

Summary
The central Australian desert ant Melophorus bagoti lives in a visually cluttered semi-arid habitat dotted with grass tussocks, bushes and trees. Previously, Bühlmann et al. (Bühlmann et al., 2011) have shown that this species has a higher propensity to switch from vector-based navigation to landmark-guided navigation, compared with the North African desert ant Cataglyphis fortis, which usually inhabits a visually bare habitat. Here we ask whether different colonies of M. bagoti, inhabiting more and less cluttered habitats, also show a similar difference. We compared ants from typically cluttered habitats with ants from an exceptional nest located on a open field largely devoid of vegetation. Ants from both kinds of nests were trained to forage from a feeder and were then displaced to a distant test site on the open field. Under these conditions, ants from cluttered habitats switched more readily from vector-based navigation to landmark-guided navigation than ants from the open field. Thus, intraspecific differences due to the experience of particular landmarks encountered en route, or of particular habitats, ride on top of previously found interspecific, inherited differences due to the evolutionary history of living in particular habitats (Bühlmann et al., 2011).
Functional properties of myoglobins from five whale species with different diving capacities
Authors: Helbo Signe , Fago Angela 
Published: June 2012

SummaryWhales show an exceptionally wide range of diving capabilities and many express high amounts of the O2 carrier protein myoglobin (Mb) in their muscle tissues that prolongs their aerobic diving capacity. Although previous studies have mainly focused on the muscle Mb concentration and O2 carrying capacity as markers of diving behavior in whales, it still remains unexplored whether whale Mbs differ in their O2 affinities and in their enzymatic activities as nitrite reductase and peroxidase enzymes, all functions that could contribute to differences in diving capacities. In this study, we have measured the functional properties of purified Mbs from five toothed whales and two baleen whales and have examined their correlation with the average dive duration. Results showed that some variation in functional properties exists among whale Mbs with the toothed whale Mbs having higher O2 affinities and nitrite reductase activities (similar to those of horse) compared with baleen whale Mbs. However, these differences did not correlate with average dive duration. Instead, a significant correlation was found between whale Mb concentration and average duration and depth of dives and between O2 affinity and nitrite reductase activity when including other mammalian Mbs. Despite the fact that the functional properties showed little species-specific differences in vitro, they may still contribute to enhancing diving capacity as a result of the increased muscle Mb concentration found in extreme divers. In conclusion, Mb concentration rather than specific functional reactivities may support whale diving performance.
The lizard celestial compass detects linearly polarized light in the blue
Authors: Beltrami Giulia , Parretta Antonio , Petrucci Ferruccio , Buttini Paola , Bertolucci Cristiano , Foà Augusto 
Published: June 2012

SummaryThe present study first examined whether ruin lizards Podarcis sicula are able to orientate using plane polarized light produced by a LCD screen. Ruin lizards were trained and tested indoors, inside an hexagonal Morris water maze, positioned under the LCD screen producing white polarized light with a single E-vector, which provided an axial cue. White polarized light did not include wavelengths in the UV. Lizards orientated correctly either when tested with E-vector parallel to the training axis or after 90° rotation of the E-vector direction, and thus validating the apparatus. Further experiments examined whether in ruin lizards there is a preferential region of the light spectrum to perceive the E-vector direction of polarized light. For this purpose, lizards reaching learning criteria under white polarized light were subdivided into 4 experimental groups. Each group was respectively tested for orientation under a different spectrum of plane polarized light (named red, green, cyan and blue) with equalized photon flux density. Lizards tested under blue polarized light orientated correctly, whereas lizards tested under red polarized light were completely disoriented. Green polarized light was barely discernible by lizards, and thus insufficient for a correct functioning of their compass. When exposed to cyan polarized light, lizard orientation performances were optimal, indistinguishable from lizards detecting blue polarized light. Overall, the present results demonstrate that perception of linear polarization in the blue is necessary - and sufficient - for a proper functioning of the sky polarization compass of ruin lizards. This may be adaptively important, since detection of polarized light in the blue improves functioning of the polarization compass under cloudy skies, i.e. when the alternative celestial compass based on detection of the sun disk is rendered useless because the sun is obscured by clouds.
The Effect of Smectite on the Corrosion of Iron Metal
Authors: Balko Barbara A. , Bossé Stephanie A. , Cade Anne E. , Jones-Landry Elise F. , Amonette James E. , Daschbach John L. 
Published: June 2012

AbstractThe combination of zero-valent iron (ZVI) and a clay-type amendment is often observed to have a synergistic effect on the rate of reduction reactions. In the present study, electrochemical techniques were used to determine the mechanism of interaction between the iron (Fe) and smectite clay minerals. Iron electrodes coated with an evaporated smectite suspension (clay-modified iron electrodes, CMIEs) were prepared using five different smectites: SAz-1, SWa-1, STx-1, SWy-1, and SHCa-1. All the smectites were exchanged with Na+ and one sample of SWy-1 was also exchanged with Mg2+. Potentiodynamic polarization scans and cyclic voltammograms were taken using the CMIEs and uncoated but passivated Fe electrodes. These electrochemical experiments, along with measurements of the amount of Fe2+ and Fe3+ sorbed in the smectite coating, suggested that the smectite removed the passive layer of the underlying Fe electrode during the evaporation process. Cyclic voltammograms taken after the CMIEs were biased at the active-passive transition potential for varying amounts of time suggested that the smectite limited growth of a passive layer, preventing passivation. These results are attributed to the Brønsted acidity of the smectite as well as to its ability to sorb Fe cations. Oxides that did form on the surface of the Fe in the presence of the smectite when it was biased anodically were reduced at a different electrochemical potential from those that form on the surface of an uncoated Fe electrode under otherwise similar conditions; this difference suggested that the smectite reacted with the Fe2+ formed from the oxidation of the underlying Fe. No significant correlation could be found between the ability of the smectite to remove the Fe passive film and the smectite type. The results have implications for the mixing of sediments and Fe particles in permeable reactive barriers, underground storage of radioactive waste in steel canisters, and the use of smectite supports in preventing aggregation of nano-sized zero-valent iron.
Peripheral Arterial Disease Associated With Caries and Periodontal Disease
Authors: Soto‐Barreras Uriel , Olvera‐Rubio Javier O. , Loyola‐Rodriguez Juan P. , Reyes‐Macias Juan F. , Martinez‐Martinez Rita E. , Patiño‐Marin Nuria , Martinez‐Castañon Gabriel A. , Aradillas‐Garcia Celia , Little James W. 
Published: June 2012

Background: Peripheral arterial disease (PAD) is an important cardiovascular disorder of the peripheral arteries. Chronic infections, such as periodontitis, may play an important role in the etiology and pathophysiology of PAD and other cardiovascular conditions. Recently, Streptococcus mutans has been found with high frequency in atheromatous plaques. The aim of this study is to evaluate the possible clinical and microbiologic association between PAD and periodontitis and dental caries.Methods: Thirty patients with PAD and 30 control individuals were selected. PAD and its severity were established by the use of the ankle‐branchial index (ABI). Clinical attachment loss (AL); probing depth; decayed, missing, and filled teeth (DMFT) index; and C‐reactive protein (CRP) levels were evaluated. The presence of bacterial DNA from Streptococcus mutans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Treponema denticola, and Aggregatibacter actinomycetemcomitans was identified by polymerase chain reaction in subgingival biofilm and serum.Results: Patients with ≥30% AL ≥ 4 mm had six‐fold increased risk of having PAD (odds ratio = 8.18; 95% confidence interval = 1.21 to 35.23; P = 0.031). There was statistical difference in the CRP (P = 0.0413) and DMFT index (P = 0.0002), with elevated number of missing teeth (P = 0.0459) in the PAD group compared with the control group. There were no significant differences in the frequency of bacteria in serum and subgingival plaque.Conclusion: There was a positive relationship between periodontitis based on AL and PAD determined by the ABI (odds ratio = 8.18).
Laser Therapy as an Effective Method for Implant Surface Decontamination: A Histomorphometric Study in Rats
Authors: Salmeron Samira , Rezende Maria L.R. , Consolaro Alberto , Sant'Ana Adriana C.P. , Damante Carla A. , Greghi Sebastião L.A. , Passanezi Euloir 
Published: June 2012

Background: To the best of the authors’ knowledge, a standard protocol for treating peri‐implantitis is not yet established.Methods: A total of 150 titanium disks with smooth or rough surfaces contaminated with microbial biofilm were implanted subcutaneously in rats after undergoing one of three treatments: 1) low‐intensity laser (LIL); 2) antimicrobial photodynamic therapy (aPDT); or 3) toluidine blue O (TBO). Sterile and contaminated disks served as negative (NC) and positive (C) control groups, respectively. After days 7, 28, and 84, tissue inflammation was evaluated microscopically by measuring the density of collagen fibers (degree of fibrosis) and concentration of polymorphonuclear neutrophils.Results: Surface texture did not affect the degree of inflammation, but the area of reactive tissue was significantly greater for rough implants (2.6 ± 3.7 × 106 µm2) than for smooth ones (1.9 ± 2.6 × 106 µm2; P = 0.0377). Group C presented the lowest and group NC presented the highest degree of fibrosis with significance only after day 7; these groups had the highest and lowest scores, respectively, for degree of inflammation. Group C showed the largest area of reactive tissue (9.11 ± 2.10 × 106 µm2), but it was not significantly larger than group LIL (P = 0.3031) and group TBO (P = 0.1333). Group aPDT showed the smallest area (4.34 ± 1.49 × 106 µm2) of reactive tissue among the treatment groups. After day 28, groups LIL, aPDT, TBO, and C resembled group NC in all the studied parameters.Conclusion: Group aPDT showed more favorable results in parameter area of reactive tissue than the other methods after day 7, but over longer time periods all methods produced outcomes equivalent to sterile implants.
Trauma Course for an Aerial Medical Transport System in the Amazon Rainforest of Ecuador
Authors: Mora Francisco E , Nicholson Benjamin , Lovelady Jay , Dhindsa Harrinder , Mata Lina V , Kleiman Debbie , Chin Theresa , King Ashley 
Published: June 2012

ABSTRACT

Objectives
Aerial transport of injured patients in rural Southeastern Ecuador is provided by humanitarian organizations with no medical personnel or assistance. We sought to evaluate the feasibility and usefulness of a tailored aeromedical transport (AMT) course for nonmedical personnel (pilot and technicians) in the jungles of Ecuador, where there are no formal medical crew members.

Methods
Fixed-wing aeromedical flights in the Amazon province of Morona Santiago were analyzed to delineate the injury patterns (IP) and reason for transport (RFT). An 8-hour didactic and hands-on AMTC course based on IP and RFT was developed and administered by the Virginia Commonwealth University (VCU) International trauma system development program (ITSDP) and VCU Life Evac with extensive experience in aeromedical education and training. Pre- and post-test course evaluation was used to assess the medical background and knowledge retention of the participants.

Results
A total of 5,716 fixed-wing aeromedical transports between Jan 2003 and Dec 2005 were analyzed. The course was developed based on 1176 (20%) RFT resulting from traumatic injuries. Course structure based on identified IP included 4 didactic lectures and hands-on skill training in aerial physiology, airway management, bleeding control, shock, musculoskeletal injuries, immobilization and patient transport. Fifteen students (4 pilots, 4 engineers, 2 physicians, 4 aerial staff and 1 flight operator) participated in the course. Pre- and post-test evaluations demonstrated significant improvement in knowledge from 53% (average 10.53, STD 1.6) to 73% (average 14.53, STD 2.13) p-value < 0.0001). Critical deficiencies in information uptake were identified in airway management and flight physiology

Conclusion
A tailored AMTC may serve as the first step toward the development of a regionally specific aeromedical transport service. Long-term follow-up is needed to evaluate the real impact of this intervention in terms of morbidity and mortality.

How to cite this article
Aboutanos MB, Mora FE, Nicholson B, Lovelady J, Dhindsa H, Mata LV, Kleiman D, Chin T, King A, Ivatury RR. Trauma Course for an Aerial Medical Transport System in the Amazon Rainforest of Ecuador. Panam J Trauma Critical Care Emerg Surg 2012;1(1):1-5.
The Role of CT Scan in Recognizing Blunt Diaphragmatic Rupture
Authors: Passos Edward , Nascimento Bartolomeu , Netto Fernando Spencer , Tien Homer 
Published: June 2012

ABSTRACT

Background
Blunt traumatic diaphragmatic rupture (BTDR) occurs when signicant deceleration mechanism and energy are applied to the torso, and it is associated with signicant injuries and high morbidity and mortality. Although it has limitations, CT scan is the diagnostic of choice for BTDR. This study is a retrospective analyse of our experience in diagnosing BTDR using the 64-slice CT scanner. Sensitivity and specicity of this exam were assessed.

Methods
We reviewed reports from 2006 to 2009 of all CT scans of the abdomen that were done in the rst 24 hours of hospitalization of blunt trauma patients. We compared CT ndings to surgery reports.

Results
Our cohort consisted of 2670 patients; 69% were male. We found 28 cases of BTDR, most of them on the patient s left side (54%). Eleven percent of cases were bilateral. BTDR was often caused by motor vehicle collisions. We found sensitivity of 86%, specicity of 99%.

Conclusion
CT scan is reliable tool in blunt trauma patients. As new technologies arise, its sensibility and specicity also increases.

How to cite this article
Passos E, Nascimento B, Netto FS, Tien H, Rizoli S. The Role of CT Scan in Recognizing Blunt Diaphragmatic Rupture. Panam J Trauma Critical Care Emerg Surg 2012;1(1):24-26.
Nonlinear Analysis of Heart Rate Variability to Assess the Reaction of Ewe Fetuses Undergoing Fetal Cardiac Surgery
Authors: Del Gaudio Costantino , Carotti Adriano , Grigioni Mauro , Morbiducci Umberto 
Published: June 2012

Fetal cardiac surgery (FCS) represents a challenging issue for the in utero treatment of congenital heart defects. However, FCS has still not gained the sufficient reliability for clinical practice due to an incompletely elucidated fetal stress response. For example, blood sampling can contribute to its onset, leading to fetoplacental unit dysfunction, one of the main causes of failure of the surgical procedure. In order to address this issue, the role of the autonomic control system during an experimental procedure of cardiac bypass on ewe fetuses was investigated by means of recurrence quantification analysis (RQA), a well-recognized method for the analysis of nonlinear systems. RQA was applied to time series extracted from fetal arterial pressure recordings before and after the cardiac bypass established by means of an extracorporeal circuit, including an axial blood pump, and taking advantage of the capability of the placenta to work as a natural oxygenator. Statistically significant correlations were found among RQA-based metrics and fetal blood gas data, suggesting the possibility to infer the clinical status of the fetus starting from its hemodynamic signals. This study shows the relevance of RQA as a complementary tool for the monitoring of the fetal status during cardiac bypass.
Influence of Extraction Methodologies on the Analysis of Five Major Volatile Aromatic Compounds of Citronella Grass (Cymbopogon nardus) and Lemongrass (Cymbopogon citratus) Grown in Thailand
Authors: Chanthai Saksit , Prachakoll Sujitra , Ruangviriyachai Chalerm , Luthria Devanand L 
Published: June 2012

Abstract
This paper deals with the systematic comparison of extraction of major volatile aromatic compounds (VACs) of citronella grass and lemongrass by classical microhydrodistillation (MHD), as well as modern accelerated solvent extraction (ASE). Sixteen VACs were identified by GC/MS. GC-flame ionization detection was used for the quantification of five VACs (citronellal, citronellol, geraniol, citral, and eugenol) to compare the extraction efficiency of the two different methods. Linear range, LOD, and LOQ were calculated for the five VACs. Intraday and interday precisions for the analysis of VACs were determined for each sample. The extraction recovery, as calculated by a spiking experiment with known standards of VACs, by ASE and MHD ranged from 64.9 to 91.2% and 74.3 to 95.2%, respectively. The extraction efficiency of the VACs was compared for three solvents of varying polarities (hexane, dichloromethane, and methanol), seven different temperatures (ranging from 40 to 160°C, with a gradual increment of 20°C), five time periods (from 1 to 10 min), and three cycles (1, 2, and 3 repeated extractions). Optimum extraction yields of VACs were obtained when extractions were carried out for 7 min with dichloromethane and two extraction cycles at 120°C. The results showed that the ASE technique is more efficient than MHD, as it results in improved yields and significant reduction in extraction time with automated extraction capabilities.