bluuebunny/crossref_metadata_2025 huggingface dataset:
Patterns of aluminum hydroxychloride deposition onto the skin
Authors: Mayeux Géraldine , Xhauflaire‐Uhoda Emmanuelle , Piérard Gérald E.
Published: March 2011

Background: Aluminum hydroxychloride (AlCl3) is an antiperspirant.

Aim: To revisit the AlCl3 deposition in vivo and in vitro on glass slides and stratum corneum (SC) harvested by cyanoacrylate skin surface strippings (CSSS).

Methods: Transepidermal water loss (TEWL) was assessed following application of 5% AlCl3 on the forearms. The AlCl3‐coated skin, glass slides and CSSS were observed using two ultraviolet light‐emitting CCD cameras in order to record changes in specular reflectance related to AlCl3 deposition. In addition, the corneoxenometry bioassay was performed in order to predict AlCl3 irritation.

Results: AlCl3 deposited on glass slides looked as linear threads and rings of similar sizes. AlCl3 deposits on skin were almost restricted inside the microrelief lines and as annular deposits at their crossings where acrosyringia are opening. After daily AlCl3 applications, deposits extended on the CSSS plateaus. At rest in absence of sweating, TEWL was decreased following AlCl3 applications. During physical exercise, the TEWL increase was limited on the AlCl3 areas. CSSS appeared unreactive to AlCl3 at the corneoxenometry bioassay.

Conclusion: The similar aspect of AlCl3 deposits on human SC and on glass slides suggested a physical property of AlCl3. Repetitive applications of AlCl3 increased both the deposit area and the barrier function.
Peer tutoring in reading in Scotland: thinking big
Authors: Topping Keith , Miller David , Thurston Allan , McGavock Karen , Conlin Nora
Published: March 2011

A large‐scale randomised‐controlled trial of reading tutoring in 80 schools in Scotland used the Paired Reading (PR) technique. On long‐term evaluation, cross‐age PR was significantly better than regular teaching, but same‐age was not. On short‐term evaluation, PR pupils did significantly better than control pupils in both years, and cross‐age and same‐age were similarly effective. Low socio‐economic pupils, lower reading ability pupils, girls and reading with maths tutoring groups did significantly better. Implementation was good in parts, but some important aspects of technique were rare. Reading gains were significantly greater for those with mistakes about every 2 minutes and those who stopped reading to talk every 5 to 7 minutes. Significant gains in self‐esteem were seen in same‐age and cross‐age groups, and for tutees and tutors, but not for controls. The relationship of achievement gain to quality of technique and socio‐emotional gains is discussed, with implications for practice.
New media, evolving multimodal literacy practices and the potential impact of increased use of the visual mode in the urban environment on young children's learning
Authors: Yamada‐Rice Dylan
Published: March 2011

This article looks at the way in which the changing visual environment affects education at two levels: in communication patterns and research methodologies. The research considers differences in the variance and quantity of types of visual media and their relationship to the written mode in the urban landscapes of Tokyo and London, using Google Street View to make comparisons. It reflects on the parallels this might have in the ways in which children encounter text in the environment. The data were analysed using Visual Content Analysis and colour coding. It found the Tokyo sample to have a higher density and diversity of visual media types at a wider range of heights. Visual and written communication also appear to be confined to more separately definable spaces with more equal weighting in the use of written and visual modes. Particularly, within the context of early childhood education it is hoped these findings will increase knowledge concerning young children's exposure to the visual mode, initiate wider discourse around this less researched mode's role within new multimodal communication practices and that the methodology furthers understanding of the potential of new media in image‐based research.
Functional Coupling between Metabotropic Glutamate Receptors and G‐Proteins in Rat Cerebral Cortex Assessed by Guanosine‐5′‐O‐(3‐[35S]thio)triphosphate Binding Assay
Authors: Odagaki Yuji , Kinoshita Masakazu , Toyoshima Ryoichi
Published: March 2011

Abstract:  Stimulation of specific guanosine‐5′‐O‐(3‐[35S]thio)triphosphate ([35S]GTPγS) binding by l‐glutamate was pharmacologically characterized in rat cerebral cortical membranes. Optimization of the experimental conditions with respect to the concentrations of GDP, MgCl2 and NaCl in assay buffer prompted us to adopt the incubation of rat cerebral cortical membranes with 0.2 nM [35S]GTPγS at 30°C for 60 min. in the presence of 20 μM GDP, 5 mM MgCl2 and 100 mM NaCl as a standard condition. Specific [35S]GTPγS binding was stimulated by l‐glutamate in a concentration‐dependent manner but not by ionotropic glutamate receptor agonists. The stimulatory responses were also elicited by many agonists for metabotropic glutamate (mGlu) receptor, with (−)‐2‐oxa‐4‐aminobicyclo[3.1.0]hexane‐4,6‐dicarboxylic acid (LY379268) being the most potent. l‐glutamate‐stimulated [35S]GTPγS binding was inhibited by several mGlu antagonists, with (2S)‐2‐amino‐2‐[(1S,2S)‐2‐carboxycycloprop‐1‐yl]‐3‐(xanth‐9‐yl) propanoic acid (LY341495) being the most potent. The pharmacological properties of a series of agonists and antagonists indicated the involvement of group II mGlu receptors, especially mGlu2. Supportive of this notion was the finding that l‐glutamate‐stimulated specific [35S]GTPγS binding was augmented by 2,2,2‐trifluoro‐N‐[4‐(2‐methoxyphenoxy)phenyl]‐N‐(3‐pyridinylmethyl)ethanesulphonamide hydrochloride (LY487379), a reportedly selective allosteric positive modulator for mGlu2, by means of upward and leftward shift of the concentration–response curve. In addition, LY487379 per se stimulated [35S]GTPγS binding, though, through a mechanism different from the stimulation by l‐glutamate. Pre‐treatment of the membranes with N‐ethylmaleimide (NEM) cancelled l‐glutamate‐stimulated [35S]GTPγS binding in a concentration‐ and incubation time‐dependent manner. Taken altogether, l‐glutamate‐stimulated [35S]GTPγS binding serves as a useful functional assay for the activation of NEM‐sensitive Gi/o‐mediated group II mGlu receptors in rat cerebral cortical membranes.
Fabrication and Characterization of Anode‐Supported BaIn0.3Ti0.7O2.85 Thin Electrolyte for Solid Oxide Fuel Cell
Authors: Rieu Mathilde , Patro Pankaj Kumar , Delahaye Thibaud , Bouyer Etienne
Published: March 2011

BaIn0.3Ti0.7O2.85 (BIT07) is a promising electrolyte for solid oxide fuel cells, due to its chemical compatibility with most of the cathode electrode material such as LSM and Ln2NiO4. The present work is aimed on the fabrication of anode‐supported half cells with thin BIT07 electrolyte. For this, Ni‐8YSZ cermet was chosen due to its excellent mechanical and electrochemical properties, in addition to its low cost. The NiO–8YSZ anode support was prepared by tape casting, and for this, an organic slurry formulation was optimized. The BIT07 electrolyte thin film was deposited through screen printing on the green anode. The formulation of the ink was optimized, and sintering at 1350°C for 3 h led to a dense electrolyte with controlled thickness varying from 2 to 12 μm. Further, the cermet electrode still had a homogeneous microstructure with well‐defined anode/electrolyte interface. The electrode ASR was about 0.5 Ω cm2 and was stable over 500 h at 800°C under H2–3% H2O. The fabrications of half cells were successfully scaled up to 100 mm × 100 mm retaining the dimensional control and without any surface defects.
Effect of Thickness and Orientation of Alumina Fibrous Thermal Insulation on Microwave Heating in a Modified Domestic 2.45 GHz Multi‐mode Cavity
Authors: Harabi Abdelhamid , Karboua Noureddine , Achour Slimane
Published: March 2011

A rectangular piece of alumina fiber insulation was designed to prevent heat loss. The heat source was generated by a susceptor material, which was used as a microwave (MW) absorber (heater). The thicknesses of different sides (frontal, lateral, and longitudinal) of the insulation piece were varied from side to side to study the penetration level of MW electromagnetic field coming from both horizontal and vertical incidences. The experience has shown an increase in temperature when top and longitudinal thicknesses were decreased. It has also been found that specific orientation of the insulation box leads to a maximum MW heating efficiency.
Development of a Test Technique to Determine the Thermal Diffusivity of Large Refractory Ceramic Test Specimens
Authors: Hemrick James G. , Dinwiddie Ralph B. , Loveland Erick R. , Prigmore Andre
Published: March 2011

A method has been developed to utilize a high‐intensity plasma arc lamp located at Oak Ridge National Laboratory for the measurement of thermal diffusivity of bulk refractory materials at elevated temperatures. The applicability of standardized test methods to determine the thermal diffusivity/conductivity of refractory materials at elevated temperatures is limited to small sample sizes (laser flash) or older test methods (hot wire, guarded hot plate), which have their own inherent problems. A new method, based on the principle of the laser flash method, but capable of evaluating test specimens on the order of 200 mm × 250 mm × 50 mm, has been developed. Tests have been performed to validate the method and preliminary results are presented in this paper.
Epidemiology of Resistant Hypertension
Authors: Sarafidis Pantelis A.
Published: March 2011

J Clin Hypertens (Greenwich). 2011;13:523–528. ©2011 Wiley Periodicals, Inc.

Resistant hypertension is an entity that has gained a lot of attention in recent years. The prevalence and prognosis of resistant hypertension have not yet been examined by proper population studies, but data from several sources suggest that this entity is not uncommon and is associated with an elevated risk of hypertensive complications. Moreover, several factors and conditions that can interfere with blood pressure control such as excess sodium intake, obesity, diabetes, older age, kidney disease, and certain identifiable causes of hypertension were shown to be common among patients with resistance to antihypertensive treatment. Importantly, the prevalence of several of these conditions has been increasing continuously during the past years, suggesting a future increase in the frequency of resistant hypertension. This article will discuss current knowledge and associated future implications relevant to the epidemiology of resistant hypertension.
TaqMan assays for the genetic identification of delta smelt (Hypomesus transpacificus) and wakasagi smelt (Hypomesus nipponensis)
Authors: BAERWALD MELINDA R. , SCHUMER GREGG , SCHREIER BRIAN M. , MAY BERNIE
Published: March 2011

We have developed species‐specific TaqMan assays for two California fish species, the threatened delta smelt (Hypomesus transpacificus) and the introduced wakasagi smelt (Hypomesus nipponensis). The assays are capable of correctly identifying each species with 100% accuracy, with no cross‐species amplification. We anticipate these assays will prove useful for future scientific studies requiring genetic species identification (e.g. predation of smelt) or monitoring (e.g. detection of delta smelt near water diversions).
Desmoplastic small round cell tumor of the pleura
Authors: Ouarssani Aziz , Atoini Fouad , Ait Lhou Fatima , Rguibi Idrissi Mustapha
Published: March 2011

In July 2006 a 19‐year‐old woman presented with a history of few months of back ache. Routine chest radiograph and computed tomography (CT) examination revealed a thickening of the parietal pleura with a collapsed right lung. The abdominal pelvic CT scan was normal. Thoracotomy was performed with decortication lung, parietal pleurectomy and pleural biopsy. The histological examination and immunohistochemical coexpression of cytokeratin AE1–AE3, vimentin and desmin confirmed the diagnosis of desmoplastic small round cell tumor of the pleura. After resection, the patient received radiotherapy and chemotherapy with doxorubicin, ifosfamide, etoposide and cisplatin in six cycles which resulted in complete remission. The patient was seen regularly in consultation; the last examination was in December 2010 and clinically and radiologically showed a stable condition. The whole follow‐up period was 53 months. We thought this case to be worth presentation because of the unusually long survival, which is probably due to the aggressive complex anticancer treatment.
81Kr‐Kr age and multiple cosmic‐ray exposure history of the Vaca Muerta mesosiderite
Authors: BAJO Ken‐ichi , NAGAO Keisuke
Published: March 2011

Abstract– Noble gas isotopic compositions were measured for a eucritic pebble and bulk material of a silicate–metal mixture from the Vaca Muerta mesosiderite as well as pyroxene and plagioclase separated from the eucritic pebble by total melting and stepwise heating methods. Trapped noble gases were degassed completely by a high‐temperature thermal event, probably at the formation of the Vaca Muerta parent body (VMPB). The presence of fissiogenic Xe isotopes from extinct 244Pu in the bulk samples might be a result of rapid cooling from an early high‐temperature metamorphism. High concentrations of cosmogenic noble gases enabled us to determine precise isotopic ratios of cosmogenic Kr and Xe. Spallogenic Ne from Na and unique Ar isotopic compositions were observed. The 81Kr‐Kr exposure age of 168 ± 8 Myr for the silicate pebble is distinctly longer than the age of 139 ± 8 Myr for the bulk samples. The precursor of the pebble had been irradiated on the surface of the VMPB for more than 60 Myr (first stage irradiation), with subsequent incorporation into bulk materials approximately 4 Gyr ago. The Vaca Muerta meteorite was excavated from the VMPB 140 Myr ago (second stage irradiation). Relative diffusion rates among the cosmogenic Ar, Kr, and Xe based on data obtained by stepwise heating indicate that Kr and Xe can be partially retained in pyroxene and plagioclase under the condition that resets the K‐Ar system. This result supports the presence of fission Xe and of excess concentration of cosmogenic Kr, which could have survived the thermal event approximately 3.8 Gyr ago.
Tracking large carnivore dispersal using isotopic clues in claws: an application to cougars across the Great Plains
Authors: Hénaux Viviane , Powell Larkin A. , Hobson Keith A. , Nielsen Clayton K. , LaRue Michelle A.
Published: March 2011

1. Cougar (Puma concolor) populations, like other large carnivores, have increased during recent decades and may be recolonizing their former ranges in Midwestern North America. The dispersal routes taken by these animals from established populations are unknown and insight into these movements would facilitate their conservation and management.

2. We inferred the origin and migration route of four dispersing cougars using stable hydrogen (δD) and carbon (δ13C) isotope values along one of their claws. We compared isotopic variations within claws to regional and large‐scale isoscapes of δD and δ13C values in prey species. Using a likelihood‐based assignment approach, we predicted the most likely dispersal route of each cougar (among several least‐cost dispersal paths to potential source populations) in a chronological sequence dating back from its final location.

3. Our model predicted the origin of a radio‐collared short‐distance disperser and inferences about the most likely dispersal corridors for two long‐distance dispersers matched reported information from re‐sighting events and genetic investigations.

4. Insights about the most likely migration corridors may help identify critical areas and guide future conservation efforts of cougars and other large carnivores. We encourage managers to extend regional isoscapes based on sedentary prey species as they prove to be valuable tools in isotopic tracking of long‐distance migration.

5. Our isotopic approach may be extended to other metabolically inert tissues that grow continuously, to investigate dispersal paths of species of interest, providing that individuals disperse across known isotopically structured landscapes.
Anxiety, alcohol intoxication, and aggression
Authors: McMurran Mary
Published: March 2011

Purpose. Research into alcohol‐related aggression has typically focused on perpetrators’ externalizing characteristics. The purpose of this exploratory review is to examine the contribution of anxiety to alcohol‐related aggression.

Arguments. Anxiety disorders are associated with externalizing disorders in childhood, but anxiety appears to protect against extreme antisocial behaviours. In contrast, in adolescence and early adulthood, anxiety appears to be associated with increased risk of antisocial behaviour. One possible explanation for this disjunction may be alcohol use, which typically starts in adolescence. Alcohol is an anxiolytic drug, which may appeal to certain young people who are socially anxious but not socially avoidant. Alcohol myopia, the cognitive mechanism whereby alcohol exerts an anxiolytic effect, is also a mechanism by which alcohol serves to increase aggression. Therefore, in anxious antisocial people, drinking to cope with anxiety is likely to increase aggression.

Conclusions. Interventions that flow from the research on anxiety, alcohol, and aggression are suggested.
Optical property improvement of InAs/GaAs quantum dots grown by hydrogen-plasma-assisted molecular beam epitaxy
Authors: Katkov A. V. , Wang C. C. , Chi J. Y. , Cheng C. , Gutakovskii A. K.
Published: March 2011

An order-of-magnitude increase of photoluminescence (PL) efficiency at room temperature has been observed in the GaAs/InAs quantum dots (QDs)-in-a-well structure grown with in situ irradiation of atomic hydrogen supplied by a radio-frequency hydrogen-plasma source. The enhancement in PL intensity rapidly increases with the hydrogen flow rate and is stable with a variation of excitation power in the radio-frequency plasma source. Extensive thermal annealing of grown samples up to 634 °C did not show any significant degradation of photoluminescence intensity compared with the reference sample. The reduction of nonradiative recombination centers in the as-grown sample causes the greatly enhanced luminescence property. In addition to PL enhancement the authors observed that the H-assisted growth of InAs QDs has suppressed bimodal distribution of QD shape. In contrast to the hydrogen-plasma-assisted growth, irradiation by hydrogen in molecular form has a detrimental effect on the optical properties of similar structures. The high thermal stability of improved optical properties suggests that the formation of the defects which are responsible for nonradiative recombination channels is suppressed during H-assisted epitaxy although in situ defect passivation by atomic hydrogen cannot be completely ruled out.
Nonconvex prior image constrained compressed sensing (NCPICCS): Theory and simulations on perfusion CT
Authors: Ramirez‐Giraldo J. C. , Trzasko J. , Leng S. , Yu L. , Manduca A. , McCollough C. H.
Published: March 2011

Purpose:

To present and evaluate a new image reconstruction method for dynamic CT based on a nonconvex prior image constrained compressed sensing (NCPICCS) algorithm. The authors systematically compared the undersampling potential, functional information recovery, and solution convergence speed of four compressed sensing (CS) based image reconstruction methods using perfusion CT data: Standard ‐based CS, nonconvex CS (NCCS), and ‐based and nonconvex CS, including an additional constraint based on a prior image (PICCS and NCPICCS, respectively).

Methods:

The Shepp–Logan phantom was modified such that its uppermost ellipses changed attenuation through time, simulating both an arterial input function (AIF) and a homogeneous tissue perfusion region. Data were simulated with and without Poisson noise added to the projection data and subsequently reconstructed with all four CS‐based methods at four levels of undersampling: 20, 12, 6, and 4 projections. Root mean squared (RMS) error of reconstructed images and recovered time attenuation curves (TACs) were assessed as well as convergence speed. The performance of both PICCS and NCPICCS methods were also evaluated using a kidney perfusion animal experiment data set.

Results:

All four CS‐based methods were able to reconstruct the phantoms with 20 projections, with similar results on the RMS error of the recovered TACs. NCCS allowed accurate reconstructions with as few as 12 projections, PICCS with as few as six projections, and NCPICCS with as few as four projections. These results were consistent for noise‐free and noisy data. NCPICCS required the fewest iterations to converge across all simulation conditions, followed by PICCS, NCCS, and then CS. On animal data, at the lowest level of undersampling tested (16 projections), the image quality of NCPICCS was better than PICCS with fewer streaking artifacts, while the TAC accuracy on the selected region of interest was comparable.

Conclusions:

The authors have presented a novel method for image reconstruction using highly undersampled dynamic CT data. The NCPICCS method takes advantage of the information provided by a prior image, as in PICCS, but employs a more general nonconvex sparsity measure [such as the ‐norm ] rather than the conventional convex ‐norm. Despite the lack of guarantees of a globally optimal solution, the proposed nonconvex extension of PICCS consistently allowed for image reconstruction from fewer samples than the analogous ‐based PICCS method. Both nonconvex sparsity measures as well as prior image information (when available) significantly reduced the number of iterations required for convergence, potentially providing computational advantages for practical implementation of CS‐based image reconstruction techniques.
Technical Note: Removing the stem effect when performing Ir‐192 HDR brachytherapy in vivo dosimetry using plastic scintillation detectors: A relevant and necessary step
Authors: Therriault‐Proulx Francois , Beddar Sam , Briere Tina M. , Archambault Louis , Beaulieu Luc
Published: March 2011

Purpose:

The purpose of this study was to investigate whether or not a stem effect removal technique is necessary when performing Ir‐192 HDR brachytherapyin vivo dosimetry using a scintillation detector.

Methods:

A red‐green‐blue photodiode connected to a multichannel electrometer was used to detect the light emitted from a plastic scintillation detector (PSD) during irradiation with an Ir‐192 HDR brachytherapy source. Accuracy in dose measurement was compared with and without the use of stem effect removal techniques. Monochromatic and polychromatic filtration techniques were studied. An in‐house template was built for accurate positioning of catheters in which the source and the PSD were inserted. Dose distribution was measured up to 5 cm from source to detector in the radial and longitudinal directions.

Results:

The authors found the stem effect to be particularly important when the source was close to the optical fiber guide and far from the scintillation component of the detector. It can account for up to of the signal under clinically relevant conditions. The polychromatic filtration outperformed the monochromatic filtration as well as the absence of filtration in regard to dose measurement accuracy.

Conclusions:

It is necessary to implement a stem effect removal technique when building a PSD forin vivo dosimetry during Ir‐192 HDR brachytherapy. The PSD that the authors have developed for this study would be suitable for such an application.
The characterization of breast anatomical metrics using dedicated breast CT
Authors: Huang Shih‐Ying , Boone John M. , Yang Kai , Packard Nathan J. , McKenney Sarah E. , Prionas Nicolas D. , Lindfors Karen K. , Yaffe Martin J.
Published: March 2011

Purpose:

Accurate anatomical characterization of the breast is useful in breast phantom development and computer modeling of breast imaging technologies. Capitalizing on the three‐dimensional capabilities of dedicated breast CT (bCT), a number of parameters which describe breast shape and fibroglandular distribution are defined.

Methods:

Among 219 bCT data sets, the effective diameter and length of the pendant breast as well as the breast volume were measured and characterized for each bra cup size. The volume glandular fraction (VGF) was determined as a function of patient age, BIRADS density, bra cup size, and breast diameter. The glandular fraction was examined in coronal and sagittal planes of the breast, and the radial distribution of breast glandular fraction within a coronal bCT image was examined for three breast regions. The areal glandular fraction (AGF) was estimated from two‐dimensional projections of the breast (simulated by projecting bCT data sets) and was compared to the corresponding VGF.

Results:

The effective breast diameter and length increase with increasing bra cup size. The mean breast diameters (± standard error) of bra cup sizes A/AA, B, C, and D/DD were , , , and , respectively. VGF was lower among older women and those with larger breast diameter and larger bra cup size. VGF increased as a function of the reported BIRADS density. AGF increased with VGF. Fibroglandular tissue was distributed primarily in the central portion of the breast.

Conclusions:

Breast metrics were examined and a number of parameters were defined which may be useful for breast modeling. The reported data may provide researchers with useful information for characterizing the breast for various imaging or dosimetry tasks.
Impact of image grading in athletes with low-risk fracture – is there a benefit?
Authors: Dobrindt O , Hoffmeyer B , Ruf J , Steffen I G , Seidensticker M , Fischbach F , Lohmann C H , Amthauer H
Published: March 2011

Background

Stress fractures (SFX) are classified by localisation (low- and high-risk) and severity, which can be determined by imaging modalities (low- and high-grade).

Objective

The objective was to determine whether a combined analysis of risk-localisation and image-grading in SFX allows a more accurate prediction of return-to-sports-time (RTST).

Design

Retrospective study. In a blinded read three independent specialists rated imaging-data (MRI and bone scintigraphy) as low- or high-grade SFX. SFX detection, risk-classification and RTST were determined by an interdisciplinary truth-panel providing a reference standard. Two-sided Wilcoxon's rank sum test and Kruskal-Wallis test were used for group comparisons.

Setting

Patients from an athlete boarding school, an Olympic training centre and from professional teams were included.

Patients

50 consecutive athletes (male, n=20; female, n=30; mean age, 23.6 years) with SFX receiving imaging were included (track, n=18; long distance running, n=16; handball, n=11; other, n=5). In all athletes follow-up data was complete until full recovery.

Interventions

All patients received standardised treatment with adaptation to sport and injury-site with special focus on safe return-to-full activity.

Main outcome measurements

Estimation of RTST depending on risk-classification and image-based grading.

Results

In our study 21/50 SFX at a high-risk localisation had a mean RTST of 135 days (d) compared to 119 d for low-risk sites (p=0.18). RTST was significantly longer (p=0.01) in imaging-based high-grade lesions (mean=143 d) than in low-grade SFX (mean=96 d). Analysis of only high-risk SFX showed no difference in RTST (p=0.58) for high- and low-grade SFX (mean, 131 d vs 140 d). In contrast the difference was significant for low-risk SFX (p=0.004; mean, low-grade=61 d vs high-grade=153 d).

Conclusion

In low-risk SFX the significant difference in RTST between low- and high-grade lesions allow a more accurate estimation of the healing time needed. As a consequence, both risk localisation and image grading of SFX have to be considered for the prediction of RTST.
Rotator cuff strength weakness in recurrent anterior shoulder instability physiopathology
Authors: Edouard P , Beguin L , Farizon F , Calmels P
Published: March 2011

Background

Although rotator cuff contractions play an important role in stabilizing the glenohumeral joint, little is known about the role of these muscles in physiopathological recurrent anterior instability.

Objective

To analyze the association between isokinetic internal rotator (IR) and external rotator (ER) muscle strength and glenohumeral joint instability in patients with nonoperated recurrent anterior instability.

Design

Case-control study.

Setting

Department of Physical Medicine and Rehabilitation, Laboratory setting.

Participants

48 subjects participated: 37 patients (25±8 yr, 179±6 cm, 74±9 kg) and 11 healthy nonathletic subjects (24±1 yr, 178±5 cm, 70±9 kg).

Interventions

ER and IR strength of 37 patients with unilateral recurrent anterior post-traumatic shoulder dislocation were compared with those of 11 healthy nonathletic subjects. Isokinetic shoulder IR and ER strength was evaluated with a Con-Trex dynamometer, in the seated position with 45° of shoulder abduction in the scapular plane. Tests were performed at 180°/s, 120°/s and 60°/s in concentric mode for both sides.

Main outcome measurements

Peak torque normalised to body weight for IR and ER and ER/IR ratio were calculated for each angular velocity. The association between IR and ER strength and shoulder instability was analyzed by side-to-side comparisons and comparisons to the control group.

Results

The association between shoulder instability and IR and ER strength was associated with side-to-side differences (p<0.05). By comparisons to a control group, strength values were lower on the pathological shoulder side than on the healthy homolateral shoulder side of controls at 180°/s and 120°/s (p<0.05). The side-to-side differences were increased when the nondominant side was involved and were decreased when dominant side was involved. We found no association between glenohumeral joint instability and ER/IR ratio.

Conclusion

IR and ER strength weakness was associated with recurrent anterior instability and side-to-side differences depended on the dominance of the side involved.
Reliability of video-based muscle flexibility measures in adolescent athletes
Authors: Fourchet F , Buchheit M , Materne O , Horobeanu C , Hudacek T , Sebo D , Millet G P
Published: March 2011

Background

Lower limbs muscle flexibility remains a common assessment in sports therapy. Nevertheless no clear consensus exists about the methods for performing reliable measurements.

Objective

The aim of the present study was to examine the reliability of muscle flexibility measures in adolescent athletes.

Design

Randomised test-retest study.

Setting

Sports academy physiotherapy laboratory.

Participants

Height young athletes (age: 15.1±1.6, body mass: 65.4±26.2 kg, height: 171.7±8.8 cm) training in a national sports centre.

Interventions

Flexibility of the main lower limb muscles was assessed, using a standardised force of stretching for each muscle and a video analysis software for measuring the angles. Each participant was tested on both sides by three operators and on two separate occasions, 4 days apart. Final measurements were reported in degrees.

Main outcome measurements

Reliability of flexibility measures was assessed by 1) calculating the between-day difference expressed as Cohen's d (90% CI), no substantial difference was considered if Cohen's d<0.2 and the 90% CI included zero, and 2) the typical error of measurement, expressed as a coefficient of variation (CV, 90% CI).

Results

Force of stretching (in N), mean angle (SD), mean between-day difference and CV were 78.5, 132.2 (10.1), −0.05 (−0.3;0.2) and 8.3% (7.5;9.3) for quadriceps, 68.7, 70 (11.2), −0.7 (−1.7;0.4) and 3.3% (3.0;3.7) for hamstrings, 39.2, 53.5 (9.4), 0.05 (−0.2;0.3) and 7.2% (6.5–8.0) for adductors, 147.2, 16 (6.3), 0.10 (−0.1;0.3) and 5.7% (5.1;6.3) for gastrocnemius, 147.2, 30.6 (8.9), 0.01 (−0.2;0.2) and 4.5% (4.0;5.0) for soleus, 98.1, 22.7 (5.9), 0.01 (−0.2;0.2) and 2.6% (2.3;2.9) for hip flexors, 49.1, 54.7 (14.5), −0.04 (−0.2;0.2) and 9.6% (8.6;10.8) for hip medial rotator and 49.1, 43.5 (14.9), −0.08 (−0.3;0.1) and 18.2% (16.3;20.5) for hip lateral rotator.

Conclusion

The present method for assessing lower limb muscles flexibility has a moderate-to-good level reliability and may integrate prevention programs.
Influence of practice characteristics on injury risk in young athletes
Authors: Frisch A , Urhausen A , Seil R , Windal T , Agostinis H , Croisier J L , Theisen D
Published: March 2011

Background

Prior research has identified athlete-related risk factors associated with increased sports injury rate. Practice characteristics of young athletes have never been investigated in this respect.

Objective

To assess the injury problem in a multi-sport setting of young athletes and to determine practice-related risk factors.

Design

Prospective epidemiological study.

Setting

Follow-up of young athletes of a Luxembourgish sport school from September 2008 to July 2009 (42 weeks).

Participants

190 athletes (14.9 ± 1.6 years) (65% boys) from 16 different sport disciplines.

Assessment of risk factors

Practice-related characteristics (context, volume, frequency and subjective intensity).

Main outcome measurements

Data pertaining to training and competition were recorded daily for each athlete. Standardised injury characteristics were registered. An injury was defined as an incident occurring during sport practice preventing the athlete to participate in at least one full training session or game.

Results

From the 190 athletes, 74% sustained at least one injury during the observation period. Injury rate was 1.65 injuries per athlete; injury incidence was 3.72 injuries/1000 h. The risk of injury was six times higher (CI95% (4.70–8.12)) in competition than in training (13.60 and 1.96 injuries/1000 h, respectively). Two thirds of the injuries were of intrinsic nature (27% progressive and 40% acute non-contact injuries). In team sports athletes having sustained at least one intrinsic injury had, compared to those with no intrinsic injury, a lower number of practice sessions per day (0.83 versus 0.89 sessions/day; p=0.023), a higher percentage of intense sessions (40 versus 30%; p=0.007), a higher number of intense sessions per day (0.33 versus 0.27 sessions/day; p=0.047) and a higher proportion of days with two intense sessions (5.7% versus 2.7%; p=0.007).

Conclusion

The relationship between practice characteristics and sports injuries should be further studied and might point to interesting prevention initiatives, provided that sports practice can be monitored.
The relationship of lower extremity alignments and anterior knee laxity to knee translations during a vertical drop landing
Authors: Myers C A , Giphart J E , Torry M R , Shelburne K B , Woo S L Y , Steadman J R
Published: March 2011

Background

Lower extremity alignment (LEA) measures have been linked to non-contact anterior cruciate ligament (ACL) injuries. High deceleration movements have been implicated in non-contact ACL injury mechanisms; and, evidence suggests that greater anterior tibial translation (ATT) may occur in healthy knees that demonstrate greater laxity compared to a stiff knee.

Objective

To determine the relationship between LEA measures, KT1000 anterior laxity values and ATT during landings using biplane fluoroscopy.

Design

Descriptive laboratory study.

Setting

Controlled laboratory setting. Subjects had a sport participation history at the high school or college level.

Participants

16 healthy adults (10 females; 6 males).

Assessment of risk factors

KT1000 values and seven measures of LEA (pelvic angle, hip anteversion, Q-angle, genu recurvatum, tibial torsion, navicular drop and rear foot angle) were measured.

Main outcome measurements

Subjects performed a drop-landing (40 cm) while being filmed using a high speed, biplane fluoroscopy system. Initial, peak and excursions for ATT were calculated and regression analysis used to determine the relationships.

Results

KT1000 values were positively correlated with peak ATT values for group (r=0.89) and both genders (males, r=0.97; females, r=0.93) (p=<0.0001). Navicular drop was also significantly correlated to maximal ATT (r=0.56) (p<0.05). No other LEA was significantly correlated with initial, peak or range of ATT (all p>0.05).

Conclusion

A strong relationship was observed between passive anterior knee laxity measured via KT1000 and ATT experienced during a landing activity in otherwise healthy persons. Navicular drop was significantly correlated with ATT during landing and is a relationship that warrants further investigation as it relates to ACL injury. Anterior knee laxity measured via the KT1000 should be considered in non-contact ACL injury risk assessment for all athletes.
Clinical evidence of a familial predisposition to anterior cruciate ligament injury
Authors: Goshima K , Kitaoka K , Nakase J , Takahashi R , Tsuchiya H
Published: March 2011

Background

Several risk factors for anterior cruciate ligament (ACL) injury have been evaluated in the literatures. It is highly probable that many of the identified risk factors for ACL injury are passed through families. However few articles describe a familial predisposition to ACL injury.

Objective

To investigate whether there is a familial predisposition to ACL injury.

Design

Retrospective study.

Methods

The study group comprised 350 consecutive patients who underwent ACL reconstruction between January 2005 and September 2008. All patients were surveyed by telephone or written questionnaire about their family history (FH) of ACL injury, sports in which family members participated and mechanisms of injury. We also compared age, height, weight, Tegner activity score, general joint laxity, and tibial slope between the FH group (with a FH of ACL injury) and a control group (without a FH of ACL injury).

Results

Complete information was obtained from 335 of the 350 patients, 38 (11.3%) of whom had a FH of ACL injury. Two families had three members with ACL injuries. Among the 40 family members with ACL injuries, 38 (95%) had a non-contact ACL injuries, and 34 (85%) injured their ACL by the same mechanism as the related patient. Comparisons of the FH and control groups identified no significant differences with regard to age, height, weight, Tegner activity score, or general joint laxity, but tibial slope was significantly larger in the FH group than in the control group.

Conclusion

Our results indicate a high probability that many of the identified risk factors for ACL injury are passed through families. Screening tests for a FH of ACL injury thus could identify a population at increased risk of ACL injury who would benefit most from preventative neuromuscular training programs designed to reduce the risk of ACL injury.
Video analysis of anterior cruciate ligament injuries in sumo wrestling
Authors: Goshima K , Kitaoka K , Shima Y , Nakase J , Takahashi R , Tsuchiya H
Published: March 2011

Background

Sumo is one of the traditional Japanese contact sports. Many sumo wrestlers suffer knee joint injuries, especially anterior cruciate ligament (ACL) injuries. ACL injuries can lead to serious consequences for injured sumo wrestlers. Therefore, Understanding the mechanisms of these injuries is crucial to prevent ACL injuries.

Objective

To describe the mechanisms of ACL injuries in sumo wrestling.

Design

Descriptive video analysis.

Methods

Eight videotapes of ACL injuries from seven professional sumo wrestlers and one high school student were collected. Four medical doctors and two physical therapists systematically analyzed these videos to describe the injury mechanisms and playing situations. We estimated knee flexion, internal/external rotation, and valgus/varus position at the time when the ACL ruptured.

Results

Two main mechanisms of ACL injuries in sumo wrestling were identified. Five knees had been injured while the wrestlers tried to make a stand at the edge of the ring, and three knees had been injured when the wrestlers tried to stay on their feet before they were thrown by their opponents. All of the mechanisms for ACL injuries were non-contact injuries; they were not caused by direct external impacts. The injuries occurred when the foot was planted and firmly fixed at the edge of the ring or the floor. In all cases, the foot was externally rotated. The knee was in flexion (the mean angle was 57.2°) and valgus, combined with internal rotation of the tibia relative to the femur.

Conclusion

Many of the sumo wrestlers suffered ACL injuries when they tried to make a stand at the edge of the ring. The mechanism of ACL injuries in sumo wrestling appeared to be non-contact injuries.
Aetiology of low back pain in young athletes: role of sport type
Authors: Hosea T , Hannafin J , Bran J , O'Hara D , Seuffert P
Published: March 2011

Background

Low back pain (LBP) in young athletes is increasing. Understanding spinal pathology related to sports may enhance design of prevention programs.

Objective

To test the hypothesis that rowing athletes with LBP have a higher likelihood of degenerative disc disease than athletes from other sports.

Design

Retrospective case series of 199 athletes (14–25 years.) with LBP.

Setting

Clinical assessment of interscholastic, intercollegiate and elite athletes presenting to a sports medicine physician complaining of LBP.

Patients

The medical records of athletes (14–25 years) seen from 2003 to 2008 with the complaint of LBP were reviewed and included. 23 sports were represented and 32% of the athletes were rowers.

Interventions

Athletes had a thorough history and physical examination, MRI and/or bone scan. Results in the rowing athletes were compared to other athletes.

Main outcome measurements

Results of the history, physical examination and radiographic studies were evaluated and the data analyzed by t-test or chi square.

Results

Demographically, the rowers and non-rowers were similar. The incidence of disc injury, involved disc levels, and physical findings were similar between the male and female rowers. Female rowers had a higher likelihood of disc herniation and a higher incidence of multiple disc level involvement than other female athletes (p<0.05). Male rowers and American football players had a higher incidence of disc herniation and multiple disc level involvement (p<0.05). Male rowers were more likely to present with positive physical findings compared to other male athletes (p<05). Overall, 89.5% of the males and 76.9% of the females had positive MRI findings affecting up to three lumbar levels.

Conclusion

Complaints of LBP in young athletes are highly correlated with lumbar spinal abnormalities. This is especially true for the young rowing athlete. Rowing techniques and training methods must be re-evaluated to decrease stresses on the lumbar spine and allow development of injury prevention programs.
The swedish athletics study: design of a protocol for large-scale epidemiological studies in individual sports
Authors: Jacobsson J , Timpka T , Ekberg J , Kowalski J , Nilsson S , Renström P
Published: March 2011

Background

Epidemiological studies of injury have mainly been performed on team sports. Present methods for data collection and analysis neglect important features of individual sports.

Aims

To develop a study protocol for large-scale epidemiological studies of injuries in individual sports, exemplified by athletics.

Design

Structured information system development. Specification of the study protocol was preceded by an examination of requirements on injury surveillance in individual sports and iterated drafting of protocol specifications, and followed by formative evaluations. A preliminary protocol was evaluated in a pilot study involving athletic coaches and athletes and revised into the final version.

Setting

Swedish youth and adult elite athletics.

Participants

Six elite athletics coaches and 22 athletic athletes.

Results

The requirements analysis showed that the central demand on a study protocol to be used for epidemiological surveillance in athletics is to enable detailed analyses of overuse injuries, which subsequently requires continuous and prospective collection of athlete self-reported data. The study protocol fulfils these requirements by using a web-based athlete diary for collection of data regarding exposure to practice and competition as well as injuries. In addition, the requirements analysis showed that the study protocol should cover collection of detailed baseline data, including injury history, subject characteristics and a psychological profile. The evaluation data showed that the preliminary protocol only needed minor revisions at the level of web-questionnaire design.

Conclusion

The resulting study protocol for injury surveillance is specifically targeted at individual sports. It can be employed in surveillance preceding intervention programs for preventing injuries and suffering among both adult elite and youth athletes. Electronic data capture is crucial for injury surveillance in individual sports, such as athletics in order to ensure high validity of data.
Stance leg frontal plane stability during lateral bounds
Authors: Jones P , Kerwin D , Irwin G , Nokes L
Published: March 2011

Background

Lower limb stability is pivotal to successful dynamic sporting movements, with poor stability during single leg tasks commonly associated with lower limb non-contact injuries.

Objective

This study investigated stance leg frontal plane stability during a lateral bound task.

Design

Players performed an infield clinical screening involving 10 alternating bounds from their left (LLEG) and right (RLEG) legs. Each bound comprised stabilisation (landing) and propulsion (lateral push off). 3D kinematic data for the stance leg (200 Hz) were captured using an automated system (CODAmotionTM) and a cluster marker set.

Setting

Professional footballers currently performing in the English Football League System performed the screening.

Participants

Five participants performed the screening.

Intervention/Assessment of risk factors

The independent variables in this study were the players involved.

Main outcome measurements

Absolute frontal plane sway (AFP-Sway) at the hip, knee and ankle were determined (Visual3DTM) and combined to provide a collective stance leg sway score (CSL-Sway) for each trial. Additionally, percentage contributions of AFP-Sway at each joint to CSL-Sway for all trials were determined and compared across players in each condition using one-way ANOVA.

Results

There were CSL-Sway differences between players within each condition, accounted for by additional motions at all three lower limb joints under LLEG conditions and only hip and knee joints under RLEG conditions. Percentage individual joint contributions to CSL-Sway differed between players at the knee and ankle joints under LLEG and all joints under RLEG conditions. Both conditions revealed two distinct bounding strategies with hip or combination of hip and ankle motions contributing the most to CSL-Sway.

Conclusions

Player differences in CSL-Sway, AFP-Sway and percentage joint contribution to CSL-Sway under both bounding conditions highlight the individualised nature of lateral bound strategies. Such objective assessment of stance leg stability may enable movement stability classification and ultimately aid injury risk identification.