bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of water level fluctuations on Vallisneria nana in the Burnett River in Southeast Queensland, Australia
Authors: Duivenvoorden Leo J. 
Published: May 2008

AbstractChanges in aquatic macrophyte populations in the Burnett River in southeast Queensland, Australia are described with respect to the effects of water level fluctuations and possible impact on the Queensland lungfish (Neoceratodus forsteri). This protected fish relies on macrophyte beds as spawning and nursery areas. Studies were conducted prior to, during and following construction of a new weir on the river. Comparative results of impounded and non‐impounded sites were conducted to investigate seasonal and inter‐annual changes in macrophytes and the effects of both a rapid rise in water level when the impoundment first filled and a decline, on new plants in shallow water. Macrophyte communities in newly inundated areas were studied to determine the time taken for seedlings to emerge and reach a cover sufficient to represent spawning habitats for the lungfish. Vallisneria nana dominated the macrophyte beds, which were scoured from the river by a large flow event in May 1998, the effects of which persisted for at least 1 year. Most newly emerging seedlings of Vallisneria perished following a small decline of 7 cm in water level. Decrease in plant biomass and death of established plants in highly turbid water resulted within 6–9 weeks following larger water level rises of 4.0–5.5 m in the new impoundment. In the period leading up to the lungfish‐spawning season at least 5 months is required for submerged plants to reach the 90% cover preferred for spawning. Implications of the results for water level management and lungfish populations are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Forecasting backwater through bridge constrictions in Mississippi River Basin
Authors: Seckin Galip , Haktanir Tefaruk , Cobaner Murat , Selek Zeliha 
Published: May 2008

AbstractHydraulic data collected in the 1960s during 92 distinct floods at 35 different bridge sites in the Mississippi River Basin revealed that the water surface profiles of these real‐life cases were distinctly different from those observed in laboratory models of the comprehensive experimental studies of the 1950s by the U.S. Geological Survey (USGS) and by U.S. Bureau of Public Roads (USBPR). The laboratory‐developed methods of USGS and USBPR yielded only about half of the field backwaters when applied to the comprehensive field data. In the current work, using the same field data and accepting a profile like that observed in the field, a new regression‐based formula for estimating bridge backwater is proposed and compared with the methods of USGS and USBPR, which yields more accurate results than these two methods with the advantage of requiring a smaller load of arithmetic operations. Copyright © 2008 John Wiley & Sons, Ltd.
Substrate indices as indicators of interstitial pore space in gravel‐bed channels
Authors: Haschenburger Judith K. , Roest Paul 
Published: May 2008

AbstractStreambed sediments that determine aquatic habitat quality are typically assessed using substrate indices. These indices are proxies for the amount of interstitial pore space that facilitates biological processes within the substrate. This study evaluates how well a suite of substrate indices characterize streambed porosity. Using the hybrid McNeil sampler, 37 cores were collected from six gravel‐bed rivers on the North Island of New Zealand. Central tendency indices correlate more strongly to porosity than critical size indices, but both types are imprecise indicators of the amount of interstitial pore space. Copyright © 2008 John Wiley & Sons, Ltd.
A novel mathematical approach for modelling time‐dependent musculoskeletal outcomes for office staff
Authors: Lu Xiaoshu , Takala Esa‐Pekka 
Published: May 2008

AbstractMusculoskeletal disorders are common in prolonged computer use. The dynamics of the relationship between musculoskeletal outcomes and duration of computer use is not easy to model by common statistical methods due to the nonlinearity of the data. The use of inappropriate statistical models increases the likelihood of drawing wrong conclusions. In this paper we present a new mathematical methodology for modelling such a dynamic data set. Data on simultaneous direct measures of computer usage and questionnaire diaries of discomfort ratings were analysed using singular value decomposition as a means to track dominant dynamic trends, which presented the common characteristic of the relationship between computer‐related workload and musculoskeletal outcomes over time. The relationship was constructed explicitly as a dose–response functional relationship that was parametrized by body region parameters. Standard statistical software was employed to quantify the variability of the estimates due to the complicated feature involved in the data. A deterministic population model was then developed to simulate the dynamics of computer‐related workload and musculoskeletal outcomes. A stochastic model was also proposed to describe the stochastic nature of dynamics for individual subjects. The model was verified by comparison with real data for forecasting purposes. Possibilities for extending the model to accommodate more complicated medical data are discussed. The mathematical model can be served as both a deterministic population model that can project the demographic consequences and a stochastic model that can describe the whole quantity evolution of the study subjects. The proposed methodology is a flexible and broadly applicable one, which can be utilized by a variety of medical research. Copyright © 2008 John Wiley & Sons, Ltd.
A nonparametric likelihood test for detecting discordance between two measurements with application to censored viral load determinations
Authors: Hu Zonghui , Follmann Dean , Qin Jing , Dewar Robin L. , Sangweni Phumelele 
Published: May 2008

AbstractPatient management frequently involves quantitative evaluation of a patient's attributes. For example, in HIV studies, a high viral load can be a trigger to initiate or modify an antiretroviral therapy. At times, a new method of evaluation may substitute for an established one, provided that the new method does not result in different clinical decisions compared with the old method. Traditional measures of agreement between the two methods are inadequate for deciding if a new method can replace the old. Especially, when the data are censored by a detection limit, estimates of agreement can be biased unless the distribution for the censored data is correctly specified; this is usually not feasible in practice. We propose a nonparametric likelihood test that seamlessly handles censored data. We further show that the proposed test is a generalization of the test on nominal measurement concordance to continuous measurement. An exact permutation procedure is proposed for implementing the test. Our application is an HIV study to determine whether one method of processing plasma samples can safely substitute for the other. The plasma samples are used to determine viral load and a large portion of data are left censored due to a lower detection limit. Copyright © 2008 John Wiley & Sons, Ltd.
Effective atomic numbers and electron densities of CuGaSe2 semiconductor in the energy range 6–511 keV
Authors: Çelik A. , Çevik U. , Bacaksiz E. , Çelik N. 
Published: May 2008

AbstractThe effective atomic numbers and electron densities of the CuGaSe2 semiconductor were calculated at 29 different energies from 6.9 to 511.0 keV by using the measured mass attenuation coefficients. Also, the mass attenuation coefficients for Cu, Ga, and Se elements were obtained at this energy range. The samples were irradiated using Cd‐109, Co‐57, Ba‐133, and Na‐22 radioactive sources. The x‐ray energies were obtained using secondary targets. The gamma and x‐rays were counted by an Ultra‐LEGe detector with a resolution of 0.55 at 122.0 keV. The mass attenuation coefficients were compared with theoretical ones obtained using the XCOM program. Copyright © 2008 John Wiley & Sons, Ltd.
Microanalysis and synthesis of calcite. Growth mechanisms on prehistoric paintings in the Large Cave, Arcy‐sur‐Cure (Yonne, France)
Authors: Chalmin E. , Sansot E. , Orial G. , Bousta F. , Reiche I. 
Published: May 2008

AbstractThe formation of subsequent layers of calcium carbonate (CaCO3) in karst caves is a well‐known phenomenon observed especially on the prehistoric paintings in the Large Cave (Grande Grotte) of Arcy‐sur‐Cure, in France. About 40 natural samples coming from the Large Cave were already investigated in a previous work and classified as a function of their crystal morphology, texture, composition and appearance. The presence of at least two calcite types was revealed on the walls: translucent and opaque white or grey calcites. The latter opaque calcites completely obstruct the paintings. The formation of these different calcites depends on various geochemical and geophysical parameters and could also be influenced by biotic processes. Questions remain about formation mechanisms leading to different calcite types and, in particular, about the role of micro‐organisms as well as interactions between prehistoric paint layers and calcite layers.Additional natural calcites were studied in order to confirm the first classification. Various syntheses of abiotic calcite were performed to study the influence of environmental parameters on calcite growth. Moreover, several series of biotic calcite were synthesised in a specific medium with two bacteria isolated from the cave in order to test their calcifying properties. All natural and synthetic samples were analysed using complementary microanalytical laboratory techniques. Micro‐x‐ray fluorescence analysis (micro‐XRF) and x‐ray absorption near‐edge structure spectroscopy (XANES) based on synchrotron radiation also enabled a more detailed distinguishing of different minerals within the complex biotic and abiotic mixtures and layered synthetic samples at microscopic scale.Comparison of natural and synthetic samples gives more detailed insights into the formation mechanisms of the different calcite types found in the Grande Grotte and allows proposing an adapted conservation strategy of its prehistoric paintings. Copyright © 2008 John Wiley & Sons, Ltd.
Distribution of selected elements in atherosclerotic plaques of apoE/LDLR‐double knockout mice assessed by synchrotron radiation‐induced micro‐XRF spectrometry
Authors: Gajda M. , Banaś K. , Banaś A. , Jawień J. , Mateuszuk Ł. , Chłopicki S. , Kwiatek W. M. , Cichocki T. , Falkenberg G. 
Published: May 2008

AbstractApolipoprotein E and LDL receptor double‐knockout (apoE/LDLR−/−) mice represent a reliable experimental model of atherosclerosis. The aim of the present study was to examine the elemental content of atherosclerotic plaques using synchrotron radiation‐induced micro x‐ray fluorescence (XRF) spectrometry. Numerous essential and trace elements were detected in cross‐sections of aortic roots collected from 6‐month‐old apoE/LDLR−/− mice fed with chow diet. Two‐dimensional maps of the elemental distribution and point recordings were compared with images of consecutive sections stained histologically, allowing precise localization of the analyzed elements in morphologically defined areas of aortic lesion. The sulphur was detected in areas occupied by macrophages and smooth muscle cells. Iron was observed in high concentrations in cardiac and smooth muscle, blood clots and in adjacent coronary vessels. Lower concentrations of iron were seen in the regions of plaques rich in macrophages and lipids. Copper was detected in higher amounts only in cardiac muscle and its concentration in plaques was very low. There was a quite high content of calcium in aortic plaque areas containing lipids and macrophages. Much higher concentrations of calcium were observed in mineral deposits, mostly located in the aortic media. Similar distribution was also characteristic for phosphorus. Zinc was observed in moderately low concentrations in atheromas. Higher content of zinc was seen in smooth musculature, in cardiac muscle and in mineral concretions. The presented results provide a substantial morphological and physicochemical background for further investigations aiming to evaluate pharmacological and dietary treatment of atherosclerosis in an apoE/LDLR−/− mouse model. Copyright © 2008 John Wiley & Sons, Ltd.
Development of a compact XRF probe using a ring‐type secondary target
Authors: Yonehara Tasuku , Tsuji Kouichi 
Published: May 2008

AbstractRecently, on‐site analysis is being performed in many fields, and the use of compact instruments is required. In this article, we developed a compact x‐ray fluorescence (XRF) probe using a ring‐type secondary target. Employing the ring‐type target, coaxial optical geometry (irradiation and detection) could be achieved. We applied this probe to standard steel materials and standard solutions. In addition, a solid sample in solution was directly measured. As an application of the XRF probe, the monitoring of a chemical reaction was demonstrated that enabled observation of an increase in metallic ions. Copyright © 2008 John Wiley & Sons, Ltd.
Trauma and Emergency Surgery: South African Model
Authors: Goosen J. , Veller M. 
Published: May 2008

AbstractSouth Africa is a low‐ to middle‐income country with huge disparities in income, and a legacy of a disadvantaged majority. During the last 30 years, many of the advantaged minority found greener pastures and emigrated to first‐world countries. We are left with a desperate shortage of specialists (including surgeons), particularly in the public sector. The need is especially acute in secondary and rural hospitals. A career in general surgery has become less attractive because of issues of lifestyle, remuneration, and the expanding requirements of the first‐world part of our population.Worldwide, South African surgeons are recognized as hardworking and capable, with a broad repertoire—because that is the way they are trained. They are backed by a relatively small group of subspecialists, and all categories of specialists are burdened by a heavy workload. Continuing surgical education is mandatory but poorly enforced.Trauma surgery and intensive care form a substantial proportion of postgraduate training and general surgical practice. In isolation, these fields cannot sustain the needs and demands for the operative skills of a general surgeon. Trauma surgeons would have to find operative general surgical work to maintain their operative skills (and credibility).Because of the large gaps in service delivery to our population, and the shortage of general surgeons, particularly in secondary centers, there is at present limited space for a discipline of emergency surgery. The primary need for our population is access to well‐trained generalists, backed by a small cadre of subspecialists.
Effect of bioactive coating of the tibial component on migration pattern in uncemented total knee arthroplasty: a randomized RSA study of 14 knees presented according to new RSA-guidelines
Authors: Therbo M. , Lund B. , Jensen K.-E. , Schrøder H. M. 
Published: May 2008

Abstract

Background
Bioactive coating of uncemented total knee arthroplasty (TKA) is believed to increase bone ingrowth and enhance early fixation of the TKA. In a prospective randomized study using radiostereometric analysis (RSA) we examined migrations of the tibial implant, in an uncemented TKA with and without bioactive coating. The study was performed according to new RSA guidelines, and focus was put on some important methodological issues.

Materials and methods
Twenty-three patients with osteoarthrosis of the knee received an uncemented Duracon TKA either with bioactive (hydroxyapatite or periapatite) coating (+HA) or without bioactive coating (−HA). Patients had RSA examinations postoperatively and at 3, 6 and 12 months. Nine patients were excluded during the study resulting in 14 knees for final analysis.

Results
At 12 months follow-up we found no significant differences in migrations between the two groups. However, in general the −HA group migrated more than the +HA group, and we found a significant larger variation in migration pattern in the −HA group. In the +HA group the tibia component stabilized after 6 months, whereas the −HA group showed continuous migration. Subsidence and posterior tilt were the main migration patterns in both groups.

Conclusions
Bioactive coating of TKA seems to enhance early stabilization of the tibia component. Similar results are found in previous studies.
Revision total hip arthroplasty using the Zweymuller femoral stem
Authors: Oetgen Matthew E. , Huo Michael H. , Keggi Kristaps J. 
Published: May 2008

AbstractBackgroundA variety of femoral stem designs have been reported to be successful in revision total hip arthroplasty without consensus as to optimal design. We evaluated the clinical and radiographic outcomes in a consecutive series of femoral revisions using a wedge-shape, tapered-stem design at medium and long-term follow-up.Materials and methodsWe performed a retrospective review of clinical and radiographic outcomes of twenty-eight consecutive femoral revisions arthroplasties, which were done using the Zweymuller femoral stem.ResultsThe mean follow-up was 7.4 years (range 2–15 years). No stem re-revision was necessary. All stems were judged to be stable by radiographic criteria at the most recent follow-up. The final mean Harris hip score was 90. There was no difference in Harris hip scores, implant stability, or radiological appearance (distal cortical hypertrophy or proximal stress shielding) of the implants between medium-term (mean 5.7 years) and long-term (mean 12.4 years) follow-up.ConclusionsWe found the Zweymuller femoral stem design to be durable for revision hip arthroplasty when there is an intact metaphyseal-diaphyseal junction for adequate press-fit stability at surgery.
Late post-operative paraparesis after rib penetration of the spinal canal in a patient with neurofibromatous scoliosis
Authors: Cappella M. , Bettini N. , Dema E. , Girardo M. , Cervellati S. 
Published: May 2008

Abstract
Rib displacement into the spinal canal is a rare cause of paraplegia or paraparesis in patients affected by neurofibromatous scoliosis. We describe a case of paraparesis in a 14-year-old child affected by neurofibromatous dystrophic kyphoscoliosis, treated with combined posterior and anterior spinal arthrodesis. Seventeen days after the surgical treatment the patient developed clinical signs and symptoms of paraparesis. A CT scan showed the head of the fifth rib protruding into the spinal canal with cord compression. Rib resection and posterior cord decompression were carried out following complete neurological recovery.
Dietary electrolytes are related to mood
Authors: Torres Susan J. , Nowson Caryl A. , Worsley Anthony 
Published: May 2008

Dietary therapies are routinely recommended to reduce disease risk; however, there is concern they may adversely affect mood. We compared the effect on mood of a low-sodium, high-potassium diet (LNAHK) and a high-calcium diet (HC) with a moderate-sodium, high-potassium, high-calcium Dietary Approaches to Stop Hypertension (DASH)-type diet (OD). We also assessed the relationship between dietary electrolytes and cortisol, a stress hormone and marker of hypothalamic–pituitary–adrenal (HPA) axis activity. In a crossover design, subjects were randomized to two diets for 4 weeks, the OD and either LNAHK or HC, each preceded by a 2-week control diet (CD). Dietary compliance was assessed by 24 h urine collections. Mood was measured weekly by the Profile of Mood States (POMS). Saliva samples were collected to measure cortisol. The change in mood between the preceding CD and the test diet (LNAHK or HC) was compared with the change between the CD and OD. Of the thirty-eight women and fifty-six men (mean age 56·3 (sem 9·8) years) that completed the OD, forty-three completed the LNAHK and forty-eight the HC. There was a greater improvement in depression, tension, vigour and the POMS global score for the LNAHK diet compared to OD (P < 0·05). Higher cortisol levels were weakly associated with greater vigour, lower fatigue, and higher levels of urinary potassium and magnesium (r 0·1–0·2, P < 0·05 for all). In conclusion, a LNAHK diet appeared to have a positive effect on overall mood.
The effect of a pre-exercise carbohydrate meal on immune responses to an endurance performance run
Authors: Chen Ya-jun , Wong Stephen Heung-sang , Wong Chun-kwok , Lam Ching-Wan , Huang Ya-jun , Siu Parco Ming-fai 
Published: May 2008

This study examined the effect of a pre-exercise meal with different glycaemic index (GI) and glycaemic load (GL) on immune responses to an endurance performance run. Eight men completed a preloaded 1 h run at 70 % VO2maxon a level treadmill followed by a 10 km performance run on three occasions. In each trial, one of the three prescribed isoenergetic meals, i.e. high GI and high GL (H-H), high GI and low GL (H-L), or low GI and low GL (L-L) was consumed by the subjects 2 h before exercise. Carbohydrate intake (% of energy intake), GI, and GL were 65 %, 79·5, and 82·4 for H-H; 36 %, 78·5, and 44·1 for H-L; 65 %, 40·2, and 42·1 for L-L, respectively. The running time for the three trials was approximately 112 min at 70 % VO2maxfor the first hour and 76 % VO2maxfor the last 52 min. Consumption of pre-exercise high-carbohydrate meals (H-H and L-L) resulted in less perturbation of the circulating numbers of leucocytes, neutrophils and T lymphocyte subsets, and in decreased elevation of the plasma IL-6 concentrations immediately after exercise and during the 2 h recovery period compared with the H-L trial. These responses were accompanied by an attenuated increase in plasma IL-10 concentrations at the the end of the 2 h recovery period. The amount of carbohydrate consumed in the pre-exercise meal may be the most important influencing factor rather than the type of carbohydrate in modifying the immunoendocrine response to prolonged exercise.
How does food-cue exposure lead to larger meal sizes?
Authors: Ferriday Danielle , Brunstrom Jeffrey M. 
Published: May 2008

Exposure to the sight and smell of food influences our momentary desire to consume it. This study explored the process by which cue exposure promotes greater consumption of food. Three hypotheses were explored, cue exposure: (i) increases the planned consumption of food; (ii) increases tolerance of larger portion sizes; (iii) arrests the development of satiety. Female participants (n50) were each tested in two conditions. In a ‘cue condition’ they were exposed to the sight and smell of pizza for 60 s. Before and after this period they provided information about prospective and maximum tolerated portion sizes and their desire to eat pizza and other non-cued foods. Participants then consumed a fixed portion of pizza, rated their hunger and were finally offeredad libitumaccess to pizza. In the ‘no-cue condition’, cue exposure was replaced with a cognitive task. Cueing had little effect on tolerance of larger portion sizes or on hunger after consuming the fixed portion. Instead, it increased prospective pizza portion size and subsequent intake of pizza. Together, these results suggest that cueing increases the amount of food that people actively plan to eat. This plan is then executed, leading to greater intake. Pizza cueing also increased prospective portion size of other foods. Thus, contrary to previous reports, effects of exposure may generalise to other foods. Finally, we found evidence that restrained eaters are less ‘cue reactive’ than unrestrained eaters. In future, our approach might be adapted to consider whether heightened ‘cue reactivity’ represents a risk factor for obesity.