bluuebunny/crossref_metadata_2025 huggingface dataset:
An Acquired Channelopathy Involving Thalamic T-Type Ca2+Channels after Status Epilepticus
Authors: Graef John D. , Nordskog Brian K. , Wiggins Walter F. , Godwin Dwayne W.
Published: April 2009

Some epilepsies are linked to inherited traits, but many appear to arise through acquired alterations in neuronal excitability. Status epilepticus (SE) is associated with numerous changes that promote spontaneous recurrent seizures (SRS), and studies have suggested that hippocampal T-type Ca2+channels underlie increased bursts of activity integral to the generation of these seizures. The thalamus also contributes to epileptogenesis, but no studies have directly assessed channel alterations in the thalamus during SE or subsequent periods of SRS. We therefore investigated longitudinal changes in thalamic T-type channels in a mouse pilocarpine model of epilepsy. T-type channel gene expression was not affected during SE; however CaV3.2 mRNA was significantly upregulated at both 10 d post-SE (seizure-free period) and 31 d post-SE (SRS-period). Overall T-type current density increased during the SRS period, and the steady-state inactivation shifted from a more hyperpolarized membrane potential during the latent stage, to a more depolarized membrane potential during the SRS period. CaV3.2 functional involvement was verified with CaV3.2 inhibitors that reduced the native T-type current in mice 31 d post-SE, but not in controls. Burst discharges of thalamic neurons reflected the changes in whole-cell currents, and we used a computational model to relate changes observed during epileptogenesis to a decreased tendency to burst in the seizure-free period, or an increased tendency to burst during the period of SRS. We conclude that SE produces an acquired channelopathy by inducing long-term alterations in thalamic T-type channels that contribute to characteristic changes in excitability observed during epileptogenesis and SRS.
Selective CB2 Receptor Agonism Protects Central Neurons from Remote Axotomy-Induced Apoptosis through the PI3K/Akt Pathway
Authors: Viscomi Maria Teresa , Oddi Sergio , Latini Laura , Pasquariello Nicoletta , Florenzano Fulvio , Bernardi Giorgio , Molinari Marco , Maccarrone Mauro
Published: April 2009

Endocannabinoids are neuroprotectivein vivoandin vitro, but the mechanisms by which they act are largely unknown. The present study addressed the role of cannabinoid receptors during remote cell death of central neurons in a model that is based on cerebellar lesions. A lesion in one cerebellar hemisphere induced remote cell death and type 2 cannabinoid receptor (CB2R) expression in contralateral precerebellar neurons. Of the selective agonists and antagonists that modulated cannabinoid receptor activity, we found that the CB2R agonist JWH-015 reduced neuronal loss and cytochrome-crelease, leading to neurological recovery; these effects were reversed by the selective CB2R antagonist SR144528. Analysis of CB2R-triggered signal transduction demonstrated that in axotomized neurons, CB2R regulated Akt and JNK phosphorylation through a PI3K-dependent pathway, whereas other major signaling routes that are dependent on CB2R, such as ERK1/2 and p38, were not involved. This result was corroborated by the observation that the selective PI3K inhibitor LY294002 blocked the CB2R stimulation effects on neuronal survival as well as Akt and JNK phosphorylation levels. Together, these data demonstrate that axonal damage induces CB2R expression in central neurons and that stimulation of this receptor has a neuroprotective effect that is achieved through PI3K/Akt signaling.
Neuromedin B and Gastrin-Releasing Peptide Excite Arcuate Nucleus Neuropeptide Y Neurons in a Novel Transgenic Mouse Expressing StrongRenillaGreen Fluorescent Protein in NPY Neurons
Authors: van den Pol Anthony N. , Yao Yang , Fu Li-Ying , Foo Kylie , Huang Hao , Coppari Roberto , Lowell Bradford B. , Broberger Christian
Published: April 2009

Neuropeptide Y (NPY) is one of the most widespread neuropeptides in the brain. Transgenic mice were generated that expressed brightRenillagreen fluorescent protein (GFP) in most or all of the known NPY cells in the brain, which otherwise were not identifiable. GFP expression in NPY cells was confirmed with immunocytochemistry and single-cell reverse transcription-PCR. NPY neurons in the hypothalamic arcuate nucleus play an important role in energy homeostasis and endocrine control. Whole-cell patch clamp recording was used to study identified arcuate NPY cells. Primary agents that regulate energy balance include melanocortin receptor agonists, AgRP, and cannabinoids; none of these substances substantially influenced electrical properties of NPY neurons. In striking contrast, neuropeptides of the bombesin family, including gastrin-releasing peptide and neuromedin B, which are found in axons in the mediobasal hypothalamus and may also be released from the gut to signal the brain, showed strong direct excitatory actions at nanomolar levels on the NPY neurons, stronger than the actions of ghrelin and hypocretin/orexin. Bombesin-related peptides reduced input resistance and depolarized the membrane potential. The depolarization was attenuated by several factors: substitution of choline for sodium, extracellular Ni2+, inclusion of BAPTA in the pipette, KB-R7943, and SKF96365. Reduced extracellular calcium enhanced the current, which reversed around −20 mV. Together, these data suggest two mechanisms, activation of nonselective cation channels and the sodium/calcium exchanger. Since both NPY and POMC neurons, which we also studied, are similarly directly excited by bombesin-like peptides, the peptides may function to initiate broad activation, rather than the cell-type selective activation or inhibition reported for many other compounds that modulate energy homeostasis.
Physical and Functional Interaction between the Dopamine Transporter and the Synaptic Vesicle Protein Synaptogyrin-3
Authors: Egaña Loreto A. , Cuevas Rolando A. , Baust Tracy B. , Parra Leonardo A. , Leak Rehana K. , Hochendoner Sarah , Peña Karina , Quiroz Marisol , Hong Weimin C. , Dorostkar Mario M. , Janz Roger , Sitte Harald H. , Torres Gonzalo E.
Published: April 2009

Uptake through the dopamine transporter (DAT) represents the primary mechanism used to terminate dopaminergic transmission in brain. Although it is well known that dopamine (DA) taken up by the transporter is used to replenish synaptic vesicle stores for subsequent release, the molecular details of this mechanism are not completely understood. Here, we identified the synaptic vesicle protein synaptogyrin-3 as a DAT interacting protein using the split ubiquitin system. This interaction was confirmed through coimmunoprecipitation experiments using heterologous cell lines and mouse brain. DAT and synaptogyrin-3 colocalized at presynaptic terminals from mouse striatum. Using fluorescence resonance energy transfer microscopy, we show that both proteins interact in live neurons. Pull-down assays with GST (glutathioneS-transferase) proteins revealed that the cytoplasmic N termini of both DAT and synaptogyrin-3 are sufficient for this interaction. Furthermore, the N terminus of DAT is capable of binding purified synaptic vesicles from brain tissue. Functional assays revealed that synaptogyrin-3 expression correlated with DAT activity in PC12 and MN9D cells, but not in the non-neuronal HEK-293 cells. These changes were not attributed to changes in transporter cell surface levels or to direct effect of the protein–protein interaction. Instead, the synaptogyrin-3 effect on DAT activity was abolished in the presence of the vesicular monoamine transporter-2 (VMAT2) inhibitor reserpine, suggesting a dependence on the vesicular DA storage system. Finally, we provide evidence for a biochemical complex involving DAT, synaptogyrin-3, and VMAT2. Collectively, our data identify a novel interaction between DAT and synaptogyrin-3 and suggest a physical and functional link between DAT and the vesicular DA system.
Uniform Signal Redundancy of Parasol and Midget Ganglion Cells in Primate Retina
Authors: Gauthier Jeffrey L. , Field Greg D. , Sher Alexander , Shlens Jonathon , Greschner Martin , Litke Alan M. , Chichilnisky E. J.
Published: April 2009

The collective representation of visual space in high resolution visual pathways was explored by simultaneously measuring the receptive fields of hundreds of ON and OFF midget and parasol ganglion cells in isolated primate retina. As expected, the receptive fields of all four cell types formed regular mosaics uniformly tiling the visual scene. Surprisingly, comparison of all four mosaics revealed that the overlap of neighboring receptive fields was nearly identical, for both the excitatory center and inhibitory surround components of the receptive field. These observations contrast sharply with the large differences in the dendritic overlap between the parasol and midget cell populations, revealing a surprising lack of correspondence between the anatomical and functional architecture in the dominant circuits of the primate retina.
Prevalence of GH deficiency in cured acromegalic patients: impact of different previous treatments
Authors: Ronchi C L , Giavoli C , Ferrante E , Verrua E , Bergamaschi S , Ferrari D I , Corbetta S , Montefusco L , Arosio M , Ambrosi B , Spada A , Beck-Peccoz P
Published: April 2009

Objective

Radiotherapy (RT) for pituitary adenomas, including GH-secreting ones, frequently leads to GH deficiency (GHD). Data on the effects of surgery alone (S) on dynamic GH secretion are limited. The aim of the study was to investigate the occurrence of GHD in acromegalic patients treated with different therapeutic options.

Design and methods

Fifty-six patients in remission from acromegaly, (33 F & 23 M, age: 54±13 years, body mass index (BMI): 28.4±4.1 kg/m2, 21 with adequately substituted pituitary deficiencies) treated by S alone (n=33, group 1) or followed by RT (n=23, group 2), were investigated for GHD by GHRH plus arginine testing, using BMI-adjusted cut-offs. Several metabolic and cardiovascular parameters (waist circumference, body fat percentage, blood pressure, fasting and post-oral glucose tolerance test glucose, HbA1c, insulin resistance and lipid profile) were evaluated in all the patients and 28 control subjects with known diagnosis of GHD.

Results

Serum GH peak after challenge was 8.0±9.7 μg/l, without any correlation with post-glucose GH nadir and IGF-1 levels. The GH response indicated severe GHD in 34 patients (61%) and partial GHD in 15 patients (27%). IGF-1 were below the normal range in 14 patients (25%). The frequency of GHD was similar in the two treatment groups (54% in group 1 and 70% in group 2). No significant differences in metabolic parameters were observed between acromegalic patients and controls with GHD.

Conclusions

Severe GHD may occur in about 60% of patients treated for acromegaly, even when cured after S alone. Thus, a stimulation test (i.e. GHRH plus arginine) is recommended in all cured acromegalic patients, independently from previous treatment.
Effects of Chronic Noise Exposure on Spatial Learning and Memory of Rats in Relation to Neurotransmitters and NMDAR2B Alteration in the Hippocampus
Authors: Cui Bo , Wu Mingquan , She Xiaojun
Published: April 2009

Effects of Chronic Noise Exposure on Spatial Learning and Memory of Rats in Relation to Neurotransmitters and NMDAR2B Alteration in the Hippocampus: Bo Cui,et al. Department of Occupational Hygiene, Institute of Health and Environmental Medicine, PR China

Objectives

The purpose of this study was to examine the effects of noise exposure on spatial learning and memory and associated mechanisms in the hippocampus (HIP).

Methods

Forty‐eight male SD rats were grouped as: A, control; B, Morris water maze (MWM) training group; C, noise exposure group; and D, noise exposure followed by MWM training group. The influence of noise stress on spatial learning and memory in rats was assessed in hidden platform acquisition training and probe trial testing in MWM. Changes in morphology of Nissl bodies were observed in the CA1, CA3 and DG regions of HIP. In order to understand the possible mechanisms behind noise stress‐induced changes, the concentration of amino acid neurotransmitters and the expression of NMDAR2B (NR2B) in HIP were also evaluated.

Results

After noise exposure, the performance of spatial learning and memory in group D was decreased significantly compared to group B. The concentration of glutamate was significantly increased in groups C and D, whereas GABA decreased markedly. The mean optical density of Nissl bodies in groups C and D was reduced in the CA1, DG and CA3 regions. The expression of NR2B was significantly decreased in the CA1, CA3 and DG regions in group C, and in the CA1 and CA3 regions in group D as compared with groups A and B.

Conclusions

Excitotoxicity, impaired Nissl bodies and reduced expression of NR2B in rat HIP induced by chronic noise exposure might have caused the impairment of spatial learning and memory.
Burnout and Risk Factors for Arteriosclerotic Disease: Follow‐up Study
Authors: Kitaoka‐Higashiguchi Kazuyo , Morikawa Yuko , Miura Katsuyuki , Sakurai Masaru , Ishizaki Masao , Kido Teruhiko , Naruse Yuchi , Nakagawa Hideaki
Published: April 2009

Burnout and Risk Factors for Arteriosclerotic Disease: Follow‐up Study: Kazuyo Kitaoka‐Higashiguchi, et al. Department of Public Health, Kanazawa Medical University

Objectives

The purpose of this longitudinal study was to investigate the effects of burnout on risk factors for arteriosclerotic disease.

Methods

Baseline data were collected from 442 male middle managers working for a manufacturing company in Japan. All participants had a physical health check‐up and completed the Japanese Maslach Burnout Inventory‐General Survey. We calculated the Japanese‐specific cut‐off points of the MBI‐GS and applied “exhaustion +1” criterion to define subjects as healthy or burnout at baseline. Follow‐up measures were collected 4–5 yr later for 383 middle managers. Changes in the subjects' waist circumference, body weight, body mass index (BMI), blood pressure, total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, fasting blood sugar, fasting insulin, HOMA‐R, and HbA1c over a time period of 4 to 5 yr were compared between the healthy and burnout groups. New cases of large waist circumference, high BMI, metabolic syndrome, hypertension, hypercholesterolemia, high triglycerides, low HDL cholesterol, high LDL cholesterol, and impaired fasting glucose were detected at follow‐up.

Results

Changes in waist circumference, body weight, and BMI were significantly greater in burned‐out managers than in healthy managers. Furthermore, compared to other variables (age and health behaviors such as smoking), burnout was a significant explanatory variable. The odds ratio of the burnout group was 2.80 for hypercholesterolemia with statistical significance after adjusting for age. After adjusting for age, health behaviors, and baseline total cholesterol, the results were similar.

Conclusions

Burnout, which results from prolonged exposure to chronic work stress, may be associated with risk factors for arteriosclerotic disease.
Chinese EPINet and Recall Rates for Percutaneous Injuries: An Epidemic Proportion of Underreporting in the Taiwan Healthcare System
Authors: Shiao Judith Shu‐Chu , McLaws Mary‐Louise , Lin Ming‐Hsiu , Jagger Janine , Chen Chiou‐Jong
Published: April 2009

Chinese EPINet and Recall Rates for Percutaneous Injuries: An Epidemic Proportion of Underreporting in the Taiwan Healthcare System: Judith Shu‐Chu Shiao, et al. Department of Nursing, National Taiwan University, College of Medicine and NTU Hospital, Taiwan

Objectives

As an occupational injury, percutaneous injury (PI) can result in chronic morbidity and death for healthcare workers (HCWs). A pilot surveillance system for PIs using the Chinese version of Exposure Prevention Information Network (EPINet) was introduced in Taiwan in 2003. We compared data from EPINet and recall of PIs using a cross‐sectional survey for rates to establish the reliability of the new system.

Methods

HCWs from hospitals that had implemented EPINet for ≥12 months completed a survey for recall of contaminated PIs sustained between October 2004 and September 2005, type of item involved, and reasons for reporting or not reporting the PI. Comparative data from EPINet for the same period were analyzed.

Results

The EPINet rate, 36.1/1,000 HCW (95%CI 31.8–41.1) was almost 5 times lower (p<0.0001) than the PI recall rate for 2,464 HCWs of 170/1,000 HCWs (95%CI 155.4–185.5). Approximately 2.5 PIs were recalled for every 1,000 bed‐days of care. The recall rate by physicians was 268.3/1,000, 188.5/1,000 for nurses, 88.9/1,000 for medical technologists and 81.3/1,000 for support staff. Hollow‐bore needle items most commonly recorded on EPINet includ, disposable needles and syringes were underreported by 81%, vacuum tube holder/needles by 67%, and arterial blood gas needles by 75%. Nearly 63% of the reasons for underreporting were related to the complexity of the reporting process, while 37% were associated with incorrect knowledge about the risks associated with PIs.

Conclusions

EPINet data underestimates a commonplace occupational injury with nearly four in five PIs not reported. Addressing the real barriers to reporting must begin with hospital administrators impressing on HCWs that reporting is essential for designing appropriate safety interventions.
A Wilkie-syndromárólr
Authors: Bognár Gábor , Ledniczky György , Palik Éva , Zubek László , Sugár István , Ondrejka Pál
Published: April 2009

Absztrakt

Számos betegség vagy noxa utáni állapot vezethet a retroperitonealis zsírszövet csökkenése következtében az arteria mesenterica superior kompressziós syndromájához. Cikkünkben egy 35 éves nőbeteg vírusfertőzés során kialakult súlyos testsúlyvesztése, majd a sikertelen konzervatív kezeléseket követő eredményes műtéte (duodeno-jejunostomia) kapcsán számolunk be a kórkép etiológiájáról, klinikumáról és kezelési lehetőségeiről a szakirodalom áttekintése alapján. Az interdiszciplináris munka különösen jelentős ebben a nehezen diagnosztizálható kórképben.
Bal alhasi fájdalom diagnosztikai és terápiás nehézségeir
Authors: Antal András , Hadijev Janaki
Published: April 2009

Absztrakt

Betegünknek bal oldali pyelonplasztika miatt hasfali sérve alakult ki. Anamnaesisében még colondiverticulumok, a lumbalis csigolyák arthrosisa, bal oldali csípőprotézis-beültetés és hasi metszésből hysterectomia szerepelt. Speciális CT-manőverek és -technikák hiányában a kis sérvet csak laparoscoppal tudtuk diagnosztizálni. A hasfali sérv felszívódó varratos kezelése csak átmeneti eredménnyel járt. A Composix háló beültetése és kapcsos rögzítése posztoperatív neuralgiát váltott ki. A szövődményt a kialakult adhaesiók oldásával és a kapcsok eltávolításával kezeltük.
Dynamic compaction of saturated sands and silty sands: theory
Authors: Thevanayagam S. , Nashed R. , Martin G. R.
Published: April 2009

Dynamic compaction (DC) with pre-installed wick drains is an emerging soil improvement technique for densification and liquefaction mitigation of saturated low-permeability loose sands containing non-plastic silts. The compaction process induces excess pore pressures, possible soil liquefaction, and concurrent densification. Wick drains relieve pore pressures and enhance densification. This paper presents a theoretical model for spatial distribution of the energy dissipated in the soil during dynamic compaction, a pore pressure model based on energy principles to estimate the spatial distribution of pore pressures induced during dynamic compaction, and a coupled consolidation model for pore pressure dissipation and soil densification. It also presents a numerical scheme to implement the theoretical models to simulate dynamic compaction at a site and obtain post-improvement soil densities or penetration resistances. A sample set of simulation results are presented. While this paper is limited to the theoretical development of the models, a second companion paper presents the results from this numerical model applied to a few case histories, and a third companion paper presents a methodology for application of the results for liquefaction mitigation design using DC in silty soils supplemented with wick drains.
Fracture grouting of sand by microfine cement grouts
Authors: Tunçdemir F. , Ergun U.
Published: April 2009

Model tests have been carried out to simulate the fracture grouting technique in loose granular soils with various fine contents. A microfine cement grout with varying water/solids ratios was used. During the tests, grouting pressures and injected volumes were recorded, and at the end of the tests the grouted soil samples were carefully exposed. Additionally, final grout shapes were observed and the soil and grouting parameters were correlated. The amount of heave occurred at the top of the specimen during injection was recorded for each test. It is seen that fracturing pressure generally decreases with an increase in the water content of the grout. Also, the fracturing pressure generally increases as the fine content of the soil increases: the increase is less at higher water/solids ratios. A higher relative density of the granular soil and a higher applied geological stress on the specimen increase the fracturing pressure significantly. The volume of grout injected into soil specimens before fracture occurs tends to increase as the water/solids ratio decreases. Soils prepared at higher relative densities and with higher fines percentages accept lower intakes before fracture.
Modelling car ownership in Turkey using neural networks
Authors: Yasin Çodur M. , Tortum A.
Published: April 2009

The present study developed an artificial neural network (ANN) approach for the forecasting of car ownership in Turkey using socio-economic and transport-related indicators. Due to the lack of disaggregate data, the model was based on aggregate data. The actual forecast was obtained using a feed-forward neural network, trained with a back-propagation algorithm. In order to investigate the influence of socio-economic indicators on car ownership, the ANN was analysed based on per capita GDP, petrol prices, car prices and road lengths along with historical car ownership available from 1971 to 1996. A comparison between model predictions and car ownership data in the test period was used for model validation. The projections were made with scenarios which were developed in order to make forecasts up to 2020. The results show that the ANN application model was more successful and reliable than the other classical models in terms of nonlinear reflection ability.
Enantioselectivity in fipronil aquatic toxicity and degradation
Authors: Nillos Mae G. , Lin Kunde , Gan Jay , Bondarenko Svetlana , Schlenk Daniel
Published: April 2009

Fipronil and its transformation products are being increasingly detected in aquatic ecosystems as a result of widespread use. Fipronil is a chiral compound, and enantioselectivity may greatly impact its environmental fate and effects. In the present study, fipronil enantiomers were isolated and used to investigate the possibility of enantioselectivity in their acute toxicity to Japanese medaka (Oryzias latipes) and cytotoxicity to primary hepatocytes from rainbow trout (Oncorhynchus mykiss). Enantioselectivity was further evaluated in terms of fipronil degradation in sediments under aerobic and anaerobic conditions and in field-contaminated runoff water from urban watersheds. The 96-h median lethal concentrations to Japanese medaka were 94.2 (95% confidence interval [CI], 82.9-107.1), 98.3 (95% CI, 85.6-113.0), and 95.4 (95% CI, 74.7-121.9) gμg/L for the racemic, R-(−)-, and S-(+)-fipronil, respectively, suggesting absence of enantioselectivity. The 24-h median effect concentration of racemic fipronil to primary rainbow trout hepatocytes was 26.7 (95% CI, 25.6-27.9) μg/ml. In contrast, exposure of the cells to the S-(+)- and R-(−)-enantiomers resulted in a 19.7 and 7.8% reduction in cell viability, respectively, at the highest treatment concentrations (100 μg/ml), potentially indicating a greater-than-additive interaction between enantiomers. Under aerobic or slightly reduced conditions, biodegradation of fipronil in sediments was essentially nonstereoselective, with the enantiomeric fraction (EF) similar to racemic (EF = 0.5) after 168 d of incubation. However, EF decreased to as low as less than 0.1 following short incubations under anaerobic conditions, suggesting preferential degradation of S-(+)-fipronil in strongly reduced sediments. A survey of urban runoff samples consistently showed near-racemic EF, indicating fipronil degradation that was not enantioselective. Results suggest that site-specific characteristics are critical in accurately predicting fipronil fate and toxicity in the environment.
High‐Yielding Corn Response to Applied Phosphorus, Potassium, and Sulfur in Nebraska
Authors: Wortmann C. S. , Dobermann A. R. , Ferguson R. B. , Hergert G. W. , Shapiro C. A. , Tarkalson D. D. , Walters D. T.
Published: April 2009

Nutrient management recommendations may change as yield levels and efficiency of crop production increase. Recommendations for P, K, and S were evaluated using results from 34 irrigated corn (Zea mays L.) trials conducted in diverse situations across Nebraska. The mean yield was 14.7 Mg ha−1 with adequate fertilizer applied. The median harvest index values were 0.52, 0.89, 0.15, and 0.56 for biomass, P, K, and S, respectively. Median grain yields were 372, 49, and 613 kg kg−1 of aboveground plant uptake of P, K, and S, respectively. The estimated critical Bray‐1 P level for corn response to 20 kg P ha−1 was 20 mg kg−1 when the previous crop was corn compared with 10 mg kg−1 when corn followed soybean [Glycine max (L.) Merr.]. Soil test K was generally high with only three site‐years <125 mg kg−1. Over all trials, application of 40 kg K ha−1 resulted in a 0.2 Mg ha−1 mean grain yield decrease. Application of 22 kg S ha−1 did not result in significant yield increase in any trial. Soil test results accounted for twice as much variation in nutrient uptake when soil organic matter (SOM) and pH were considered in addition to the soil test nutrient values. The results indicate a need to revise the current recommendation for P, to maintain the current K and S recommendations, and to use SOM and pH in addition to soil test nutrient values in estimating applied nutrient requirements for irrigated high yield corn production.
Stability of Rice Grain and Whole Kernel Milling Yield is Affected by Cultivar and Date of Planting
Authors: Blanche Sterling B. , Linscombe Steve D.
Published: April 2009

The objectives of this study were to evaluate rice (Oryza sativa L.) cultivar stability and to characterize different planting dates for their consistency in grain yield and milling. Eight rice cultivars and seven planting dates were evaluated from 2003 to 2005 for a total of 19 yr × planting date environments. The coefficient of variation of cultivars and planting dates, a measure of relative variation that approximates stability, were compared along with mean performance to demonstrate a new method for interaction between the genotype × environment (GEI) evaluation of multi‐environment datasets. Planting date was the most significant component of the total variation in grain yield due to environment while year, as a source of variation, was more significant for whole kernel milling yield. ‘Jupiter,’ a medium‐grain type, was the highest yielding cultivar in the study but was also one of the least stable as evidenced by a large coefficient of variation. ‘Cypress’ and ‘CL161’ were among the most stable cultivars and exhibited high grain and whole kernel milling yields suggesting that they would be ideal cultivar selections for planting at less than optimum times or when abnormal conditions occur for rice planted during the recommended timeframe. Based on high grain and milling yields and consistent performance across years and cultivars, the optimum date for planting rice at this location was PD4. The methods and statistics we demonstrated in this study do not require expensive commercial software packages, are simple to compute and easily interpreted, and should have widespread applicability across most crops and locations.
Introduction: Can Water Use Efficiency Be Modeled Well Enough to Impact Crop Management?
Authors: Evett Steven R. , Tolk Judy A.
Published: April 2009

Crop water use efficiency (WUE, yield per unit of water use) is key for agricultural production with limited water resources. Policymakers and water resource managers working at all scales need to address the multitudinous scenarios in which cropping systems and amounts, timing and methods of irrigation, and fertilizer applications may be changed to improve WUE while meeting yield and harvest quality goals. Experimentation cannot address all scenarios, but accurate simulation models may fill in the gaps. The nine papers in this special section explore how four simulation models were used to simulate yield, water use, and WUE of cotton (Gossypium hirsutum L.), maize (Zea mays L.), quinoa (Chenopodium quinoa Willd.), and sunflower (Helianthus annuus L.) in North and South America, Europe, and the Middle East. All the models simulated WUE adequately under well‐watered conditions, but tended to misestimate WUE under conditions of water stress, which limits their use for exploration of deficit irrigation scenarios or rain‐fed or dryland situations with expected soil water deficits. None of the experimental conditions reported involved separate measurements of evaporation (E) and transpiration (T); so there was no opportunity to test the separation of E and T simulated in the newest of the models, AquaCrop. The lack of separate E measurements also limited the authors in exploring reasons why WUE was not simulated well under water stress conditions. Future studies exploring WUE simulation should include E or T measurements so that effects of management methods that reduce E can be studied.
Psychosocial Analysis of HIV/AIDS-Related Stigma in South Africa
Authors: Cooper Sara , Foster Don
Published: April 2009

Eleven well-educated students from a university in South Africa, all actively involved in the field of HIV/AIDS, were interviewed through a free-associative-narrative method. This study sought to explore students' perceptions of HIV/AIDS in an attempt to assess whether stigma may occur. To the authors' knowledge, no similar studies exploring HIV/AIDS-related stigma have been done on young adults in South Africa who are actively involved with, and highly educated on, issues around HIV/AIDS. Through their representations, the participants tend to “other” the epidemic and thus distance themselves from a sense of threat. Many of the discourses in which the participants invest also fit into existing power relations, reinforcing some of the most prevalent forms of oppression in South Africa. In line with psychosocial understandings of HIV/AIDS stigma, the results indicate that this “atypical” group of students possess stigmatizing tendencies toward the epidemic and those infected. The findings have both theoretical and practical implications for conceptualizing and challenging HIV/AIDS stigma.
Potential applications of fluorhydroxyapatite as biomaterials in medicine
Authors: Vitkovič Martin , Noaman Maha , Palou Martin , Jantová Soňa
Published: April 2009

The present work was undertaken to investigate the bioactivity and cytotoxicity of fluorhydroxyapatite ceramics. The bioactivity was evaluated by in vitro testing in simulated body fluid (SBF), in which ion concentrations are almost identical with inorganic ion concentrations of human blood plasma. Pellets of FA, HA and FHA were immersed in SBF for 48 hours, 1 week and 4 weeks at 36.5°C. Changes of the surface microstructure of the samples were observed by scanning electron microscopy (SEM). 48 hours and one week immersion in SBF did not result in any substantial progress in bioactivity. After 4 weeks in SBF a new biologically active layer was created on the surface of the biomaterials. In addition, the embryonal mouse fibroblast cell line NIH-3T3 was used for a comparative study of basal cytotoxicity of FHA, HA and FA discs. The sensitivity of these cells for tested biomaterials was evaluated on the basis of two cytotoxic end points: cell proliferation and cell morphology. The basal cytotoxicity of FHA, FA and HA discs was measured by a direct contact method. After 24, 48 and 72 hours, the cell growth was evaluated by direct counting of non-affected cells and cells treated by biomaterials. After 72 hours of biomaterials treatment, about 25% inhibition of cell number and unchanged morphology was found.
Student Speech Rights and the Special Characteristics of the School Environment
Authors: Warnick Bryan R.
Published: April 2009

Since the Tinker decision, the Supreme Court has maintained that student First Amendment rights are modified by the “special characteristics of the school environment.” The nature of these characteristics, however, has not been adequately investigated. The author proposes seven characteristics of schools that are relevant to speech rights: (a) the age of students, (b) attendance requirements, (c) multiple school constituencies, (d) heightened safety considerations, (e) the need for public accountability, (f) the school-associated nature of much student speech, and (g) the need to promote educational goals. A preliminary examination of these characteristics leads to a complex picture of student rights. In the face of such complexity, the author proposes that if speech rights are to be limited because of educational concerns, they must be limited in a way that is itself educational.
Return to Sports following Operatively Treated Ankle Fractures
Authors: Colvin Alexis C. , Walsh Michael , Koval Kenneth J. , McLaurin Toni , Tejwani Nirmal , Egol Kenneth
Published: April 2009

Background:

This study investigated which variables influence patients' return to sports after operative fixation of an unstable ankle fracture.

Materials and Methods:

Over a 5-year period, 488 patients underwent surgical repair of an unstable ankle fracture. 243 patients preoperatively identified themselves as participating in vigorous activity. Clinical evaluation, functional outcome scores, and radiographic findings were reviewed retrospectively.

Results:

At 3 months postoperatively, only 3% of all patients had returned to full sports. At 6 months, 14% of patients had returned, while at one year, only 24% of patients had returned. Younger age was predictive of return to sports by 3 months ( p = 0.02), 6 months ( p = 0.02) and 12 months ( p = 0.0001). Males were more likely to return to sports at 6 ( p = 0.001) and 12 months ( p = 0.040). At 1 year, 88% of recreational athletes had returned to sports, while only 11.6% of competitive athletes had returned to sports ( p = 0.043). At 12 months, bimalleolar injuries were more likely to return to sports than unimalleolar ankle fractures ( p = 0.042). Furthermore, patients without an associated syndesmotic injury were more likely to return to athletic activities at 12 months ( p = 0.011). A patient with an ASA of one or two was ten times more likely to return to sports versus a patient with an ASA of three or four (odds ratio >10, p = 0.010).

Conclusion:

Predictors of return to sporting activities at one year include younger age, male gender, no or mild systemic disease, and a less severe ankle fracture. Negative predictors include older age, female gender, and the presence of severe medical comorbidities. Level of Evidence: III, Retrospective Case Control Series
Joint Preservation of the Osteoarthritic Ankle Using Distraction Arthroplasty
Authors: Tellisi Nazzar , Fragomen Austin T. , Kleinman Dawn , O'Malley Martin J. , Rozbruch S. Robert
Published: April 2009

Background:

In recent years ankle distraction arthroplasty has gained popularity in the treatment of ankle arthritis as a means of both maintaining range of motion and avoiding fusion. We present a retrospective review of 25 patients who have undergone ankle distraction from 1999 to 2006.

Materials and Methods:

The mean age was 43 years; 16 were male, and 7 were female. Followup was 30 months after frame removal (range, 12 to 60 months). We were able to obtain followup on 23 of 25 patients. Adjuvant procedures were performed in some cases including Achilles tendon lengthening (5), ankle arthroscopy (4), open arthrotomy (1), and supramalleolar tibial and distal fibular osteotomy to correct distal tibial deformity (6).

Results:

Twenty-one patients (91%) reported improved pain with those furthest post-op experiencing the best results. The average preoperative AOFAS score was 55 (range, 29 to 82), and the average postoperative score was 74 (range, 47 to 96). The difference between pre- and postoperative scores was significant ( p = 0.005). SF-36 scores showed modest improvement in all components. Only two of the patients in the study underwent fusion after ankle distraction. Total ankle motion was maintained in all patients with improvement in the functional arc of motion in five patients who started with mild equinus contractures.

Conclusion:

We feel that ankle distraction offers a promising solution for many people with ankle arthritis. Level of Evidence: IV, Retrospective Case Series
Flatfoot Prevalence and Foot Dimensions of 5– to 13-Year-Old Children in Taiwan
Authors: Chen Jiann-Perng , Chung Meng-Jung , Wang Mao-Jiun
Published: April 2009

Background:

The prevalence of flatfeet in normal and obese children has not been studied well in the past. The prevalence of flatfoot and foot dimensions of school children in Taiwan were investigated in this study.

Materials and Methods:

One thousand twenty-four school children (549 boys and 475 girls) aged 5 to 13 years participated in this study. Fifteen foot dimensions were measured using a 3D coordinate measuring probe, digital tape measure and Harris mat imprint. Two-way ANOVA was conducted to evaluate the flatfoot and obesity effects on foot dimensions as well as on the change in foot size between weightbearing and nonweightbearing conditions.

Results:

The prevalence of flatfoot for 5- to 13-year-old children was 28% with a decreasing trend with age. Boys had a significantly higher frequency for flatfoot than girls (chi-square = 26.3; p < 0.001). The prevalence of flatfoot was 35% in boys and 20% in girls. The percent of overweight and obese children was 20%. A significant difference in the prevalence of flatfoot occurred between normal-weight (27%), overweight (31%), and obese (56%) children (chi-square = 18.0; p < 0.001). The obesity effect was significant ( p < 0.01) for most foot dimensions. However, the flatfoot effect was only significant ( p < 0.05) on foot height for both genders.

Conclusion:

Obese children have a higher frequency of flatfoot, greater foot dimensions, and less change in foot width with weightbearing than normal weight children. Children with flatfeet have a lower foot height and greater foot length change than children with normal feet with weightbearing. Level of Evidence: III, Comparative Case Series
Intensity, repetitiveness, and directionality of habitual adolescent mobility patterns influence the tibial diaphysis morphology of athletes
Authors: Shaw Colin N. , Stock Jay T.
Published: April 2009

Mobility patterns affect the loads placed on the lower limbs during locomotion and may influence variation in lower limb diaphyseal robusticity and shape. This relationship commonly forms the basis for inferring mobility patterns from hominin fossil and skeletal remains. This study assesses the correspondence between athletic histories, varying by loading intensity, repetition and directionality, measured using a recall questionnaire, and peripheral quantitative computed tomography‐derived measurements of tibial diaphysis rigidity and shape. Participants included male university varsity cross‐country runners (n = 15), field hockey players (n = 15), and controls (n = 20) [mean age: 22.1 (SD +/− 2.6) years]. Measurements of tibial rigidity (including J, %CA, Imax, Imin, and average cortical thickness) of both runners and field hockey players were greater than controls (P ≤ 0.05). Differences in tibial shape (Imax/Imin, P ≤ 0.05) between runners and hockey players reflect pronounced maximum plane (Imax) rigidity in runners, and more symmetrical hypertrophy (Imax, Imin) among hockey players. This corresponds with the generally unidirectional locomotor patterns of runners, and the multidirectional patterns of hockey players. These results support the relationship between mobility and tibial diaphysis morphology as it is generally interpreted in the anthropological literature, with greater levels of mobility associated with increased diaphyseal robusticity and shape variation. Although exercise intensity may be the primary influence on these properties, the repetitiveness of the activity also deserves consideration. In conclusion, bone morphological patterns can reflect habitual behaviors, with adaptation to locomotor activities likely contributing to variation in tibial rigidity and shape properties in archaeological and fossil samples. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.
Preparation of N‐alkylpyridinium aryl ketone derivatives via the surfactant promoted cross‐coupling reaction of N‐alkylpyridiniumboronic acids with carboxylic anhydride in water at room temperature
Authors: Matondo H. , Garrigues J. C. , Rico‐Lattes I. , Lattes A.
Published: April 2009

The palladium (II) chloride catalyzed coupling reaction of N‐alkylpyridiniumboronic acids with benzoic anhydride was carried out smoothly in water to give high yields of ketones without the use of a phosphine ligand. The reaction was conducted under mild conditions at room temperature. In this article, by focusing on the Suzuki reaction, it is shown how this method can impact modern synthetic chemistry, making reactions faster, easier and cleaner. Copyright © 2009 John Wiley & Sons, Ltd.
Self‐assembled three‐dimensional flower‐like α‐Fe2O3 nanostructures and their application in catalysis
Authors: Zhang Wu , Chen Jie , Wang Xiang , Qi Hongling , Peng Kaishan
Published: April 2009

Three‐dimensional flower‐like α‐Fe2O3 nanostructures have been successfully synthesized by a simple surfactant‐free environmental friendly solvolthermal process. The as‐prepared products were investigated by X‐ray powder diffraction, transmission electron microscopy, and field emission scanning electron microscopy. By adjusting the synthetic parameters, the shape of the α‐Fe2O3 nanostructures can be controlled. The three‐dimensional flower‐like α‐Fe2O3 nanostructures were found to be highly active as catalysts for phenol alkylation. The effects of various parameters, such as reaction temperature, reaction time and the amount of catalyst, were studied. The catalyst was stable and could be reused three times in normal atmosphere without suffering appreciable loss in catalytic activity. Copyright © 2009 John Wiley & Sons, Ltd.
Multiple neural networks modeling techniques in process control: a review
Authors: Ahmad Zainal , Mat Noor Rabiatul ′Adawiah , Zhang Jie
Published: April 2009

This paper reviews new techniques to improve neural network model robustness for nonlinear process modeling and control. The focus is on multiple neural networks. Single neural networks have been dominating the neural network ‘world’. Despite many advantages that have been mentioned in the literature, some problems that can deteriorate neural network performance such as lack of generalization have been bothering researchers. Driven by this, neural network ‘world’ evolves and converges toward better representations of the modeled functions that can lead to better generalization and manages to sweep away all the glitches that have shadowed neural network applications. This evolution has lead to a new approach in applying neural networks that is called as multiple neural networks. Just recently, multiple neural networks have been broadly used in numerous applications since their performance is literally better than that of those using single neural networks in representing nonlinear systems. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Urban versus rural residence and occurrence of septal heart defects in Texas
Authors: Langlois Peter H. , Scheuerle Angela , Horel Scott A. , Carozza Susan E.
Published: April 2009

BACKGROUND:

There is conflicting information on the association between urban/rural residence of mothers and atrial septal defect (ASD) or ventricular septal defect (VSD) in their offspring. Few studies have compared multiple measures of urban/rural residence.

METHODS:

Data were taken from the Texas Birth Defects Registry, 1999–2003. Poisson regression was used to compare crude and adjusted birth prevalence.

RESULTS:

Three broad urban/rural measures, namely, the rural urban continuum code (RUCC), urban influence code (UIC), and rural urban commuting area (RUCA), were correlated with each other, but much less correlated with percentage of land in crops. ASD showed few consistent patterns with RUCC, UIC, and RUCA but was more prevalent in counties with higher cropland percentage. For example, counties with ≥50% cropland had a prevalence ratio (PR) for isolated ASD of 3.49 (95% confidence interval [CI]: 2.85–4.24) compared to counties with <15% cropland. VSD was less prevalent in rural areas using RUCC, UIC, and RUCA. For example, for isolated VSD, small towns/rural areas had a PR of 0.64 (95% CI: 0.51–0.78) compared to urban core areas using RUCA. The pattern was seen among mild cases of VSD but not among severe cases. VSD was not associated with percentage cropland.

CONCLUSIONS:

The measure of urban/rural status can greatly affect associations with certain birth defects. More prevalent ASD in areas with greater percentage cropland suggests that agricultural chemicals may be relevant. Mild cases of VSD but not severe cases were less prevalent in rural areas, suggesting that variation in detection may be largely responsible. Birth Defects Research (Part A) 2009. © 2009 Wiley‐Liss, Inc.
Challenges and regulatory experiences with non‐inferiority trial design without placebo arm
Authors: Hung H. M. James , Wang Sue‐Jane , O'Neill Robert
Published: April 2009

For a non‐inferiority trial without a placebo arm, the direct comparison between the test treatment and the selected positive control is in principle the only basis for statistical inference. Therefore, evaluating the test treatment relative to the non‐existent placebo presents extreme challenges and requires some kind of bridging from the past to the present with no current placebo data. For such inference based partly on an indirect bridging manipulation, fixed margin method and synthesis method are the two widely discussed methods in the recent literature. There are major differences in statistical inference paradigm between the two methods. The fixed margin method employs the historical data that assess the performances of the active control versus a placebo to guide the selection of the non‐inferiority margin. Such guidance is not part of the ultimate statistical inference in the non‐inferiority trial. In contrast, the synthesis method connects the historical data to the non‐inferiority trial data for making broader inferences relating the test treatment to the non‐existent current placebo. On the other hand, the type I error rate associated with the direct comparison between the test treatment and the active control cannot shed any light on the appropriateness of the indirect inference for faring the test treatment against the non‐existent placebo. This work explores an approach for assessing the impact of potential bias due to violation of a key statistical assumption to guide determination of the non‐inferiority margin.
Sample size re‐estimation in clinical trials
Authors: Proschan Michael A.
Published: April 2009

Adaptive clinical trials are becoming very popular because of their flexibility in allowing mid‐stream changes of sample size, endpoints, populations, etc. At the same time, they have been regarded with mistrust because they can produce bizarre results in very extreme settings. Understanding the advantages and disadvantages of these rapidly developing methods is a must. This paper reviews flexible methods for sample size re‐estimation when the outcome is continuous.