bluuebunny/crossref_metadata_2025 huggingface dataset:
Early nut development as a resistance factor to the attacks of Curculio nucum (Coleoptera: Curculionidae)
Authors: Guidone L. , Valentini N. , Rolle L. , Me G. , Tavella L.
Published: May 2007

The nut weevil Curculio nucum (Coleoptera: Curculionidae) is responsible for high yield losses in several hazelnut‐growing areas of Europe and Turkey, if not regularly controlled using pesticides. The resistance of hazelnut varieties to the nut weevil is known but poorly investigated so far. Thus a 2‐year study was carried out to investigate factors affecting C. nucum attacks on two cultivars [Tonda Gentile delle Langhe (TGL), Ennis] and four selections (Daria, 101, B6, L35) in a 15‐year‐old orchard of northwestern Italy. Nut developmental stages and shell characteristics, such as hardness and thickness, were measured and correlated to the biological cycle of the nut weevil and to the damage by its larvae. During the 2‐year sampling, nut weevil adults were collected on all cultivars and selections, but in greater quantities on TGL and Daria, and in lower quantities on 101 and B6. In 2005, by female dissection, mature eggs were observed from late June, when the mean temperature exceeded 18°C. Differences between cultivars and selections were found in nut and kernel development, and in shell hardening; in particular, the kernel development was directly related with the shell hardness. At harvest, the damage varied on average from 2.57% in cultivar TGL to 51.84% in selection 101 of total nuts harvested, so independently of the numbers of the collected weevil adults. These two varieties were the earliest and the latest in kernel development and shell hardening, respectively. Therefore, the susceptibility to nut weevil attacks was strictly related to shell hardening; in fact, a rapid hardening of the shell can hamper the oviposition of C. nucum females. By contrast, no correlation was found between shell thickness and damage at harvest.
Output and Price Determination in the Canadian Chicken Industry: Which Should Come First?
Authors: Gervais Jean‐Philippe , Guillemette Karine , Romain Robert
Published: May 2007

Bilateral bargaining between chicken producers and processing firms determined chicken prices in Ontario from 1995 to 2002. A significant reform in 2003 introduced a formula‐based live price that is a function of chicken producers' costs. The latter pricing mechanism reduces the risk faced by processing firms and producers because the chicken price is known when output decisions are made. However, the pricing formula also involves some risk in that the cost components may be far removed from actual costs when production is carried out. Expected farm prices under the two different pricing mechanisms are also not identical. The producers' and processors' expected utility of profits under each pricing mechanism is computed. The bargaining pricing mechanism generally yields higher expected utility for producers than the formula‐based price. Conversely, processing firms obtain a higher expected utility under the formula‐based pricing than under the bargaining framework. These conclusions critically hinge on the size of the producers' margin component in the formula‐based price. In that sense, the formula‐based pricing mechanism did not lessen the significance of relative bargaining strengths in establishing the distribution of welfare in the chicken industry.

Des négociations bilatérales entre les producteurs de poulet et les entreprises de transformation déterminaient le prix du poulet vivant en Ontario de 1995 à 2002. Une formule de prix établie en fonction des coûts de production des producteurs de poulet fut introduite en 2003. Ce mécanisme réduit le risque auquel sont confrontés les transformateurs et les producteurs parce que le prix du poulet vivant est connu lorsque les décisions de production sont prises. Cependant, la formule de prix comporte aussi un risque dans le sens où la composante du coût dans la formule de prix peut être différente des coûts réels de production du poulet vivant. Les prix espérés du poulet vivant sont aussi différents dans les deux systèmes de prix. L'utilité espérée des profits pour les producteurs et les transformateurs de poulet est calculée dans les deux mécanismes. Le modèle fondé sur la négociation génère une utilité espérée des profits plus élevée pour les producteurs que la formule de prix. À l'inverse, les transformateurs obtiennent une utilité espérée des profits plus élevée selon la formule de prix que selon le modèle fondé sur la négociation. Ces conclusions sont étroitement liées à la taille de la marge des producteurs utilisée dans le calcul de la formule de prix. Dans ce sens, l'introduction d'un nouveau mécanisme de détermination des prix n'a pas modifié l'importance du pouvoir relatif de négociation dans la distribution du surplus économique au sein de la filière canadienne du poulet.
Effects of 22‐Oxacalcitriol and Calcitriol on PTH Secretion and Bone Mineral Metabolism in a Crossover Trial in Hemodialysis Patients With Secondary Hyperparathyroidism
Authors: Ogata Hiroaki , Koiwa Fumihiko , Shishido Kanji , Takahashi Keiko , Ito Hidetoshi , Kinugasa Eriko , Taguchi Susumu
Published: May 2007

Abstract:  The purpose of this crossover comparison study is to elucidate the differences between the effects of a novel calcitriol analog, 22‐oxacalcitriol, and calcitriol on parathyroid hormone (PTH) and bone mineral metabolism in hemodialysis patients with secondary hyperparathyroidism (SHPT). Twenty‐three patients with moderate to severe SHPT were included in a random 2 × 2 crossover trial with two vitamin D analogs (12 weeks for each treatment). Two patients withdrew during the run‐in period for personal reasons. Serum electrolyte, bone metabolic marker, intact PTH (iPTH) and whole PTH (wPTH) levels were measured periodically. The primary endpoint measure was a decrease in serum iPTH level, and the secondary outcome measures included changes in serum calcium (Ca), phosphate (P), and metabolic bone marker levels. Both treatments decreased iPTH and wPTH levels by similar degrees. Serum Ca, P, and Ca × P product levels at the end of each treatment were comparable and the frequencies of hypercalcemia and hyperphosphatemia were also similar during each treatment period. 22‐Oxacalcitriol significantly decreased the levels of bone metabolic markers, namely, bone‐specific alkaline phosphate, intact osteocalcin, pyridinoline, and cross‐linked N‐telopeptide of type I collagen, after a 12‐week treatment. In contrast, calcitriol did not change any of the levels of bone metabolic markers. The present study showed that 22‐oxacalcitriol is equally effective for PTH suppression, and Ca and P metabolism. In addition, 22‐oxacalcitriol might have putative actions on bone remodeling independent of its PTH suppression. Further study is necessary to confirm the effects of 22‐oxacalcitriol on bone metabolism in SHPT.
A search for 22-GHz H2O masers in supernova remnants
Authors: Woodall J. M. , Gray M. D.
Published: May 2007

We have examined 18 known supernova remnants for evidence of the 22.235-GHz water maser spectral line, using the 20-m telescope at the Onsala observatory in Sweden. No evidence of such emission was discovered above the background noise in any of the observations. We have developed a radiative transfer water maser model for the shocked regions of supernova remnants in order to determine why this emission was not detected. The model indicates an insignificant amount of 22.235-GHz gain; the gain lengths are far too short to allow the formation of detectable water masers from these objects. We predict that only in unusual environments can 22-GHz water masers be detected around supernova remnants.
Predicting the frequencies of diverse exo-planetary systems
Authors: Greaves J. S. , Fischer D. A. , Wyatt M. C. , Beichman C. A. , Bryden G.
Published: May 2007

Extrasolar planetary systems range from hot Jupiters out to icy comet belts more distant than Pluto. We explain this diversity in a model where the mass of solids in the primordial circumstellar disc dictates the outcome. The star retains measures of the initial heavy-element (metal) abundance that can be used to map solid masses on to outcomes, and the frequencies of all classes are correctly predicted. The differing dependences on metallicity for forming massive planets and low-mass cometary bodies are also explained. By extrapolation, around two-thirds of stars have enough solids to form Earth-like planets, and a high rate is supported by the first detections of low-mass exo-planets.
Exciting the magnetosphere of the magnetar CXOU J164710.2–455216 in Westerlund 1
Authors: Muno M. P. , Gaensler B. M. , Clark J. S. , de Grijs R. , Pooley D. , Stevens I. R. , Zwart S. F. Portegies
Published: May 2007

We describe XMM–Newton observations taken 4.3 d prior to and 1.5 d subsequent to two remarkable events that were detected with Swift on 2006 September 21 from the candidate magnetar CXOU J164710.2–455216: (i) a 20-ms burst with an energy of 1037 erg (15–150 keV), and (ii) a rapid spin-down (glitch) with ΔP/P∼−10−4. We find that the luminosity of the pulsar increased by a factor of 100 in the interval between observations, from 1 × 1033 to 1 × 1035 erg s−1 (0.5–8.0 keV), and that its spectrum hardened. The pulsed count rate increased by a factor of 10 (0.5–8.0 keV), but the fractional rms amplitude of the pulses decreased from 65 to 11 per cent, and their profile changed from being single-peaked to exhibiting three distinct peaks. Similar changes have been observed from other magnetars in response to outbursts, such as that of 1E 2259+586 in 2002 June. We suggest that a plastic deformation of the neutron star crust induced a very slight twist in the external magnetic field, which in turn generated currents in the magnetosphere that were the direct cause of the X-ray outburst.
Detecting Differential Speededness in Multistage Testing
Authors: Van Der Linden Wim J. , Breithaupt Krista , Chuah Siang Chee , Zhang Yanwei
Published: May 2007

A potential undesirable effect of multistage testing is differential speededness, which happens if some of the test takers run out of time because they receive subtests with items that are more time intensive than others. This article shows how a probabilistic response‐time model can be used for estimating differences in time intensities and speed between subtests and test takers and detecting differential speededness. An empirical data set for a multistage test in the computerized CPA Exam was used to demonstrate the procedures. Although the more difficult subtests appeared to have items that were more time intensive than the easier subtests, an analysis of the residual response times did not reveal any significant differential speededness because the time limit appeared to be appropriate. In a separate analysis, within each of the subtests, we found minor but consistent patterns of residual times that are believed to be due to a warm‐up effect, that is, use of more time on the initial items than they actually need.
Recent Advances in Imaging in Management of Symptomatic Internal Carotid Artery Disease
Authors: Szabo Kristina , Kern Rolf , Hennerici Michael G.
Published: May 2007

The management of patients with internal carotid artery stenosis needs to focus on the occurrence and identification of neurological symptoms, the degree and morphology of the stenosis and the determination of the mechanism of cerebral ischemia. Thus neuroimaging studies are an integral part of the neurologist's assessment of these patient and individual therapeutic decisions. Since a differentiated approach is not always taken and patients by far too often undergo surgical or interventional treatment without a proper neurological evaluation, the material presented in this review demonstrates the possibilities of such a critical assessment concerning brain and vascular imaging findings and new techniques as well as modern concepts of plaque vulnerability improving the understanding of the pathophysiology and mechanisms of ischemic symptoms in internal carotid artery disease. Furthermore, the results of recent clinical trails that need to be integrated in the optimal treatment plan of these patients are discussed.
The Changing Face of the Burden of Stroke in Japan
Authors: Shinohara Yukito
Published: May 2007

The pattern of stroke in Japan has become similar to that in western countries in recent decades: the incidence of stroke, as well as the death rate, has decreased tremendously, with a decreasing stroke/coronary heart disease (CHD) ratio, decreasing proportions of intracerebral hemorrhage (ICH) and lacunar infarction, and increasing proportions of atherothrombotic and cardio embolic stroke. These changes reflect the availability of health insurance for all Japanese, widespread use of antihypertensive therapy, increasing average age of the population, and lifestyle changes. The newly introduced Japan Stroke Society (JSS)-approved stroke specialist system is also described.
Surveillance and Measuring Trends of Stroke in Japan: The Takashima Stroke Registry (1988 – Present)
Authors: Kita Yoshikuni , Turin Tanvir Chowdhury , Rumana Nahid , Sugihara Hideki , Morita Yutaka , Hirose Kunihiko , Okayama Akira , Nakamura Yasuyuki , Ueshima Hirotsugu
Published: May 2007

The Takashima Stroke Registry is a disease registration system for stroke established in Japan in 1988. This stroke registry is a population-based, prospective, observational study whose objective is to monitor trends in the incidence and case-fatality of stroke in Japan. Takashima County is located in the rural area of the Shiga prefecture in central Japan, having a stable population of approximately 54,000. It is a farming community with similar cultural values and standards of living throughout the region. The population has remained fairly stable during the 16-year study period. 1750 stroke cases (men 937 and women 813) were registered during 1988–2002. The average ages of the men and women patients were 69.4 and 74.4 years respectively. Stroke diagnostic criteria are established for the Monitoring System for Cardiovascular Disease commissioned by the Ministry of Health and Welfare, Japan. These criteria were based on WHO-MONICA project. Takashima registry system was planned to capture all the cases in the study area by covering all the hospitals of the county. To ensure that eligible patients hospitalized outside the county were not omitted, registration procedures were also conducted at three high-level medical facilities within the Shiga region but outside the county. Due to the high rate of computed tomography use in Japan the identification of stroke cases within the study area is almost complete and stroke diagnosis and classification are accurately recorded.
The 2006 Helsingborg Consensus Conference on European Stroke Strategies
Authors: Norrving Bo
Published: May 2007

The 2nd Helsingborg Consensus Conference on European Stroke Strategies, was held March 2006 with the aims to update core issues in stroke management, to monitor progress, and to set new targets for the year 2015. the congress was organized by the International Society of Internal Medicine, endorsed by the European Stroke Council and the International Stroke Society, and co-sponsored by the WHO Regional Office for European. The meeting prepared the 2nd Helsingborg Declaration which details principles of care, research and development areas, and targets for the year 2015 in 5 areas of stroke management: organization of stroke services, management of acute stroke, prevention, rehabilitation, and evaluation of stroke outcome and quality assessment.

The burden of stroke in European will increase markedly in the next decades. There is substantial evidence on insufficient control of major risk factors for stroke, in particular hypertension. The organization of stroke services plays a key role in the provision of effective therapies, but stroke units and facilities for provision of thrombolytic therapy remain suboptimal. Cognitive long term effects of stroke, and caregiver strain, have been underrecognized areas. Quality assessment as an integral part of services is still not established in most geographical areas.

Several of the original Helsingborg Declaration goals for 2005 were found not to have been met. Some goals for 2015 in the 2nd Helsingborg Declaration was therefore kept unchanged or only slightly modified.

The present report summarizes the proceedings held during the conference and provides further perspectives on the 2006 Helsingborg Declaration.
VITATOPS, the VITAmins TO Prevent Stroke Trial: Rationale and Design of a Randomised Trial of B-Vitamin Therapy in Patients with Recent Transient Ischaemic Attack or Stroke (NCT00097669) (ISRCTN74743444)
Authors:   The VITATOPS Trial Study Group
Published: May 2007

Background

Epidemiological studies suggest that raised plasma concentrations of total homocysteine (tHcy) may be a common, causal and treatable risk factor for atherothromboembolic ischaemic stroke, dementia and depression. Although tHcy can be lowered effectively with small doses of folic acid, vitamin B12 and vitamin B6, it is not known whether lowering tHcy, by means of B vitamin therapy, can prevent stroke and other major atherothromboembolic vascular events.

Aim

To determine whether the addition of B-vitamin supplements (folic acid 2 mg, B6 25 mg, B12 500 μg) to best medical and surgical management will reduce the combined incidence of stroke, myocardial infarction (MI) and vascular death in patients with recent stroke or transient ischaemic attack (TIA) of the brain or eye.

Design

A prospective, international, multicentre, randomised, double blind, placebo-controlled clinical trial.

Setting

One hundred and four medical centres in 20 countries on five continents.

Subjects

Eight thousand (6600 recruited as of 5 January, 2006) patients with recent (7 months) stroke (ischaemic or haemorrhagic) or TIA (brain or eye).

Randomisation

Randomisation and data collection are performed by means of a central telephone service or secure internet site.

Intervention

One tablet daily of either placebo or B vitamins (folic acid 2mg, B6 25 mg, B12 500 μg).

Primary outcome

The composite of stroke, MI or death from any vascular cause, whichever occurs first. Outcome and serious adverse events are adjudicated blinded to treatment allocation.

Secondary outcomes

TIA, unstable angina, revascularisation procedures, dementia, depression.

Statistical power

With 8000 patients followed up for a median of 2 years and an annual incidence of the primary outcome of 8% among patients assigned placebo, the study will have at least 80% power to detect a relative reduction of 15% in the incidence of the primary outcome among patients assigned B vitamins (to 6·8%/year), applying a two-tailed level of significance of 5%.

Conclusion

VITATOPS aims to recruit and follow-up 8000 patients between 1998 and 2008, and provide a reliable estimate of the safety and effectiveness of folic acid, vitamin B12, and vitamin B6 supplementation in reducing recurrent serious vascular events among a wide range of patients with TIA and stroke throughout the world.
Stroke and Cardiovascular Diseases: The Need for a Global Approach for Prevention and Drug Development
Authors: Hilbrich Lutz , Truelsen Thomas , Yusuf Salim
Published: May 2007

Background

Research into the prevention and treatment of stroke and cardiovascular disease has focused primarily on the needs of high-income countries (HIC). However, the majority of all stroke and cardiovascular deaths occurs in low- and middle-income countries (LMIC), with further rises in these countries predicted.

Summary of review

In HIC, proven strategies for the treatment of stroke and cardiovascular disease are well established and cost-effective. Developing strategies to include LMIC is therefore crucial to curb the global epidemic of stroke and cardiovascular disease. For example, pharmaceutical companies are being encouraged to make certain drugs more affordable in low- and middle-income companies, and the same principle could be applied to drugs for the prevention of stroke. Furthermore, centers from LMIC are now often included in clinical trials, resulting in trials that are more globally relevant and affordable and that enhance the participation of healthcare professionals from a broad range of countries.

Conclusions

More cost-effective drug development processes and affordable prices, while protecting intellectual property rights, will prevent the ever-increasing burden of stroke becoming unmanageable in LMIC.
Promoting Acute Thrombolysis for Ischaemic Stroke (PRACTISE)
Authors: Dirks Maaike , Niessen Louis W. , Huijsman Robbert , van Wijngaarden Jeroen , Minkman Mirella M. N. , Franke Cees L. , van Oostenbrugge Robert J. , Koudstaal Peter J. , Dippel Diederik W. J.
Published: May 2007

Rationale

Thrombolysis with intravenous rtPA is an effective treatment for patients with ischaemic stroke if given within 3 h from onset. Generally, more than 20% of stroke patients arrive in time to be treated with thrombolysis. Nevertheless, in most hospitals, only 1–8% of all stroke patients are actually treated. Interorganisational, intraorganisational, medical and psychological barriers are hampering broad implementation of thrombolysis for acute ischaemic stroke.

Aims

To evaluate the effect of a high-intensity implementation strategy for intravenous thrombolysis in acute ischaemic stroke, compared with regular implementation; to identify success factors and obstacles for implementation and to assess its cost-effectiveness, taking into account the costs of implementation.

Design

The PRACTISE study is a national cluster-randomised-controlled trial. Twelve hospitals have been assigned to the regular or high-intensity intervention by random allocation after pair-wise matching. The high-intensity implementation consists of training sessions in conformity with the Breakthrough model, and a tool kit. All patients who are admitted with acute stroke and onset of symptoms not longer than 24 h are registered.

Study outcomes

The primary outcome measure is treatment with thrombolysis. Secondary outcomes are admission within 4 h after onset of symptoms, death or disability at 3 months, the rate of haemorrhagic complications in patients treated with thrombolysis, and costs of implementation and stroke care in the acute setting. Tertiary outcomes are derived from detailed criteria for the organisational characteristics, such as door-to-needle time and protocol violations. These can be used to monitor the implementation process and study the effectiveness of specific interventions.

Discussion

This study will provide important information on the effectiveness and cost-effectiveness of actively implementing an established treatment for acute ischaemic stroke. The multifaceted aspect of the intervention will make it difficult to attribute a difference in the primary outcome measure to a specific aspect of the intervention. However, careful monitoring of intermediate parameters as well as monitoring of accomplished SMART tasks can be expected to provide useful insights into the nature and role of factors associated with implementation of thrombolysis for acute ischaemic stroke, and of effective acute interventions in general.
Imaging the Cellular Biology of the Carotid Plaque
Authors: U-King-Im Jean Marie , Tang Tjun , Moustafa Ramez R. , Baron Jean Claude , Warburton Elizabeth A. , Gillard Jonathan H.
Published: May 2007

Carotid atherosclerotic disease is a significant preventable cause of stroke. Clinical decision-making in current practice is based primarily on detection of the severity of luminal stenosis, as determined by ultrasound or conventional angiographic imaging modalities. New insights in the biology of atherosclerosis now suggests that the morphological characteristics of the carotid plaque as well as the molecular and cellular processes occurring within it may be more important markers of plaque vulnerability and stroke risk. This review summarizes emerging applications in the molecular imaging of atherosclerosis and detection of the vulnerable carotid plaque. We discuss how advances in imaging platforms and biochemical technology (e.g. targeted contrast agents) have driven some exciting and promising novel diagnostic imaging approaches from bench to bedside.
Worldwide Under-Funding of Stroke Research
Authors: Pendlebury Sarah T.
Published: May 2007

The clinical and financial burdens of stroke are considerable. Stroke is the leading cause of death and disability in the developed world and incidence is rapidly increasing in the developing world. However, investment in research to combat stroke has been remarkably poor. Studies from the United Kingdom, Europe and the United States have shown a highly consistent picture, with considerably lower levels of funding for stroke research compared with cancer and heart disease. Without better funding for stroke research, it is unlikely that progress in prevention and treatment will offset the projected increases in the burden of stroke. Stroke physicians and public interest groups need to be active advocates in securing increased funding for stroke research.
Increased fat oxidation and regulation of metabolic genes with ultraendurance exercise
Authors: Helge J. W. , Rehrer N. J. , Pilegaard H. , Manning P. , Lucas S. J. E. , Gerrard D. F. , Cotter J. D.
Published: May 2007

Aim:  Regular endurance exercise stimulates muscle metabolic capacity, but effects of very prolonged endurance exercise are largely unknown. This study examined muscle substrate availability and utilization during prolonged endurance exercise, and associated metabolic genes.

Methods:  Data were obtained from 11 competitors of a 4‐ to 5‐day, almost continuous ultraendurance race (seven males, four females; age: 36 ± 11 years; cycling o2peak: males 57.4 ± 5.9, females 48.1 ± 4.0 mL kg−1 min−1). Before and after the race muscle biopsies were obtained from vastus lateralis, respiratory gases were sampled during cycling at 25 and 50% peak aerobic power output, venous samples were obtained, and fat mass was estimated by bioimpedance under standardized conditions.

Results:  After the race fat mass was decreased by 1.6 ± 0.4 kg (11%; P < 0.01). Respiratory exchange ratio at the 25 and 50% workloads decreased (P < 0.01) from 0.83 ± 0.06 and 0.93 ± 0.03 before, to 0.71 ± 0.01 and 0.85 ± 0.02, respectively, after the race. Plasma fatty acids were 3.5 times higher (from 298 ± 74 to 1407 ± 118 μmol L−1; P < 0.01). Muscle glycogen content fell 50% (from 554 ± 28 to 270 ± 25 nmol kg−1 d.w.; n = 7, P < 0.01), whereas the decline in muscle triacylglycerol (from 32 ± 5 to 22 ± 3 mmol kg−1 d.w.; P = 0.14) was not statistically significant. After the race, muscle mRNA content of lipoprotein lipase and glycogen synthase increased (P < 0.05) 3.9‐ and 1.7‐fold, respectively, while forkhead homolog in rhabdomyosarcoma, pyruvate dehydrogenase kinase 4 and vascular endothelial growth factor mRNA tended (P < 0.10) to be higher, whereas muscle peroxisome proliferator‐activated receptor γ co‐activator‐1β mRNA tended to be lower (P = 0.06).

Conclusion:  Very prolonged exercise markedly increases plasma fatty acid availability and fat utilization during exercise. Exercise‐induced regulation of genes encoding proteins involved in fatty acid recruitment and oxidation may contribute to these changes.
Changes in signalling pathways regulating protein synthesis in human muscle in the recovery period after endurance exercise
Authors: Mascher H. , Andersson H. , Nilsson P.‐A. , Ekblom B. , Blomstrand E.
Published: May 2007

Aim:  Exercise induced alterations in the rate of muscle protein synthesis may be related to activity changes in signalling pathways involved in protein synthesis. The aim of the present study was to investigate whether such changes in enzyme phosphorylation occur after endurance exercise.

Methods:  Six male subjects performed ergometer cycling exercise for 1 h at 75% of the maximal oxygen uptake. Muscle biopsy samples from the vastus lateralis were taken before, immediately after, 30 min, 1 h, 2 h and 3 h after exercise for the determination of protein kinase B (PKB/Akt), mammalian target of rapamycin (mTOR), glycogen synthase 3 kinase (GSK‐3), p70S6 kinase (p70S6k) and eukaryotic elongation factor 2 (eEF2) phosphorylation.

Results:  The phosphorylation of Akt was unchanged directly after exercise, but two‐ to fourfold increased 1 and 2 h after the exercise, whereas GSK‐3α and β phosphorylation were two‐ to fourfold elevated throughout most of the 3‐h recovery period. Phosphorylation of mTOR was elevated threefold directly after, 30 min and 2 h after exercise and eEF2 phosphorylation was decreased by 35–75% from 30 min to 3 h‐recovery. Exercise led to a five‐ to eightfold increase in Ser424/Thr421 phosphorylation of p70S6k up to 30 min after exercise, but no change in Thr389 phosphorylation.

Conclusions:  The marked decrease in eEF2 phosphorylation suggests an activation of translation elongation and possibly protein synthesis in the recovery period after sustained endurance exercise. The lack of p70S6k activation suggests that translation initiation is activated via alternative pathways, possibly via the activation of eukaryotic initiating factor 2B.
Multidecadal Climate Variability and Drought in the United States
Authors: Goodrich Gregory B.
Published: May 2007

The history of multidecadal climate variability and drought in the United States during the past millennium is reviewed, and recent research into the physical mechanisms that produce long‐term aridity is examined. Numerous multiyear droughts that have major social repercussions for contemporary and prehistoric societies can be identified in instrumental and proxy records. The 16th‐century megadrought in the Southwest was the worst long period of aridity in the past 500 years. A prolonged period of aridity in the western United States from 900 to 1300 AD, which coincided with the Medieval Warm Period, is indicative of a mean shift in climate that ended in roughly 1400 AD. While the causes of these and other multiyear droughts are still under investigation, there is strong statistical and modeled evidence that persistent La Niña‐like sea surface temperatures in the tropical Pacific force hemispheric and zonal symmetry in multidecadal droughts. In other words, persistent cooler than normal sea surface temperatures in the tropical Pacific force anomalous atmospheric circulations that produce multiyear droughts not only in the Great Plains and the Southwest, but also in the Mediterranean region of Europe, the Pampas region of South America, the steppes of Central Asia, and the outback of Western Australia. Other possible causes of long period drought include low‐frequency variability in the north Pacific and Atlantic oceans and global warming in the Anthropocene.
Participatory Development: From Epistemological Reversals to Active Citizenship
Authors: Mohan Giles
Published: May 2007

The past decade has witnessed the ubiquity of participation in governance across the globe, involving efforts to bring more marginalised people into the decision‐making processes that affect them. At one level, there is an apparent consensus around the need to reconnect citizens with the policy process, which has seen experiments in different forms of direct democracy. Common to these experiments is changing epistemologies in terms of knowing what marginalised people feel and need. This article charts the rise of participatory governance and offers a critique of the epistemological assumptions that underpin it. A key critique is that changing epistemologies, by themselves, are no guarantee of more meaningful participation so that concerted institutional change is also needed. I argue that for participation to become more transformatory we need to see it as a form of citizenship in which political processes are institutionalised and people can hold others to account. This revitalised citizenship agenda is also spatialised in that peoples’ understandings of the world and the political channels available to them are locally differentiated and contingent. The conclusion is a call for more geographically sensitive empirical research on the unfolding of new forms of participation.
Classification of Cassava Starch Films by Physicochemical Properties and Water Vapor Permeability Quantification by FTIR and PLS
Authors: Henrique C.M. , Teófilo R.F. , Sabino L. , Ferreira M.M.C. , Cereda M.P.
Published: May 2007

ABSTRACT: Cassava starches are widely used in the production of biodegradable films, but their resistance to humidity migration is very low. In this work, commercial cassava starch films were studied and classified according to their physicochemical properties. A nondestructive method for water vapor permeability determination, which combines with infrared spectroscopy and multivariate calibration, is also presented. The following commercial cassava starches were studied: pregelatinized (amidomax 3550), carboxymethylated starch (CMA) of low and high viscosities, and esterified starches. To make the films, 2 different starch concentrations were evaluated, consisting of water suspensions with 3% and 5% starch. The filmogenic solutions were dried and characterized for their thickness, grammage, water vapor permeability, water activity, tensile strength (deformation force), water solubility, and puncture strength (deformation). The minimum thicknesses were 0.5 to 0.6 mm in pregelatinized starch films. The results were treated by means of the following chemometric methods: principal component analysis (PCA) and partial least squares (PLS) regression. PCA analysis on the physicochemical properties of the films showed that the differences in concentration of the dried material (3% and 5% starch) and also in the type of starch modification were mainly related to the following properties: permeability, solubility, and thickness. IR spectra collected in the region of 4000 to 600 cm−1were used to build a PLS model with good predictive power for water vapor permeability determination, with mean relative errors of 10.0% for cross‐validation and 7.8% for the prediction set.
Application of Atomic Force Microscopy as a Nanotechnology Tool in Food Science
Authors: Yang Hongshun , Wang Yifen , Lai Shaojuan , An Hongjie , Li Yunfei , Chen Fusheng
Published: May 2007

ABSTRACT:  Atomic force microscopy (AFM) provides a method for detecting nanoscale structural information. First, this review explains the fundamentals of AFM, including principle, manipulation, and analysis. Applications of AFM are then reported in food science and technology research, including qualitative macromolecule and polymer imaging, complicated or quantitative structure analysis, molecular interaction, molecular manipulation, surface topography, and nanofood characterization. The results suggested that AFM could bring insightful knowledge on food properties, and the AFM analysis could be used to illustrate some mechanisms of property changes during processing and storage. However, the current difficulty in applying AFM to food research is lacking appropriate methodology for different food systems. Better understanding of AFM technology and developing corresponding methodology for complicated food systems would lead to a more in‐depth understanding of food properties at macromolecular levels and enlarge their applications. The AFM results could greatly improve the food processing and storage technologies.
Neurovascular coupling in the mammalian brain
Authors: Filosa Jessica A. , Blanco Víctor M.
Published: May 2007

Normal brain function requires proper supply of oxygen and glucose in a timely and local manner. This is achieved through an orchestrated intercellular communication between neurones, astrocytes and microvessels that results in a rapid and restricted increase in cerebral blood flow, a process known as neurovascular coupling. Astrocytic end‐feet make close contacts with neuronal synapses and blood vessels and, given their ability to release vasoactive signals following neuronal activation, have been recognized as key intermediaries in the neurovascular response. Both dilating and constricting signals appear to be released from astrocytes upon increases in intracellular Ca2+ concentration, and both dilatation and constriction of brain vessels have been observed in previous studies. In this article, we discuss the various astrocyte‐derived vasodilating and vasoconstricting signals, their interactions and effects on astrocytes and vascular smooth muscle cells, and suggest the importance of the intrinsic properties of the latter cell type on the overall neurovascular response. We present a working model in which the rise in astrocytic Ca2+ following neuronal activation leads not only to the rapid activation of calcium‐activated K+ channels in astrocytic end‐feet, but also to their modulation by metabolites of the arachidonic acid pathway, which in general have been proposed to act on vascular smooth muscle cells rather than on astrocytes. We propose that this latter mechanism may in turn modulate K+ signalling from astrocytes to smooth muscle cells, influencing the overall effects of the vasodilating and vasoconstricting signals released during neuronal activation.
Differential aerobic exercise‐induced changes in plasma aldosterone between African Americans and Caucasians
Authors: Jones Jennifer M. , Dowling Thomas C. , Park Jung‐Jun , Phares Dana A. , Park Joon‐Young , Obisesan Thomas O. , Brown Michael D.
Published: May 2007

Aldosterone influences the kidney's regulation of blood pressure (BP), but aldosterone can contribute to the pathogenesis of hypertension. Blood pressure is reduced with aerobic exercise training (AEX), but the extent to which plasma aldosterone (PA) levels change is unclear. The purpose of this study was to determine whether 6 months of AEX changed PA levels, 24 h sodium (Na+) excretion and BP in prehypertensive and hypertensive subjects and whether these changes differed according to ethnicity. The study was performed in the Kinesiology Department at the University of Maryland, College Park, and 35 (22 Caucasian; 13 African American) sedentary prehypertensive and hypertensive subjects completed 6 months of AEX. Blood samples were collected under fasting and supine conditions, and PA was measured by radioimmunoassay. In total population aerobic exercise training increased maximal oxygen consumption (24 ± 0.8 versus 28 ± 1 ml kg−1 min−1, P < 0.001) and decreased PA levels (97 ± 11 versus 72 ± 6 pg ml−1, P= 0.01), body mass index (28 ± 0.5 versus 28 ± 0.5 kg m−2, P= 0.004) and weight (85 ± 2 versus 83 ± 2 kg, P= 0.003). Aerobic exercise training decreased PA levels (from 119 ± 16 to 81 ± 7 pg ml−1, P= 0.02) in the Caucasians but there was no change in BP or Na+ excretion. African American participants had no significant changes in PA levels, BP and Na+ excretion. Plasma aldosterone levels were 47% lower at baseline (P= 0.01) and 30% lower after AEX (P= 0.04) in African American participants compared with Caucasians. Baseline (P= 0.08) and final PA levels (P= 0.17) did not differ between the two groups after accounting for baseline and final intra‐abdominal fat, respectively. The reduction in PA levels with AEX appeared to be driven by the change in PA levels in Caucasian participants. Fat distribution contributed to the ethnic differences in PA levels.
Isotonic contractile impairment due to genetic CLC‐1 chloride channel deficiency in myotonic mouse diaphragm muscle
Authors: Van Lunteren Erik , Pollarine Jennifer , Moyer Michelle
Published: May 2007

The hallmark of genetic CLC‐1 chloride channel deficiency in myotonic humans, goats and mice is delayed muscle relaxation resulting from persistent electrical discharges. In addition to the ion channel defect, muscles from myotonic humans and mice also have major changes in fibre type and myosin isoform composition, but the extent to which this affects isometric contractions remains controversial. Many muscles, including the diaphragm, shorten considerably during normal activities, but shortening contractions have never been assessed in myotonic muscle. The present study tested the hypothesis that CLC‐1 deficiency leads to an impairment of muscle isotonic contractile performance. This was tested in vitro on diaphragm muscle from SWR/J‐Clcn1adr‐mto/J myotonic mice. The CLC‐1‐deficient muscle demonstrated delayed relaxation, as expected. During the contractile phase, there were significant reductions in power and work across a number of stimulation frequencies and loads in CLC‐1‐deficient compared with normal muscle, the magnitude of which in many instances exceeded 50%. Reductions in shortening and velocity of shortening occurred, and were more pronounced when calculated as a function of absolute than relative load. However, the maximal unloaded shortening velocity calculated from Hill's equation was not altered significantly. The impaired isotonic contractile performance of CLC‐1‐deficient muscle persisted during fatigue‐inducing stimulation. These data indicate that genetic CLC‐1 chloride channel deficiency in mice not only produces myotonia but also substantially worsens the isotonic contractile performance of diaphragm muscle.
Evaluation of Fluid Dispensing Systems Using Axiomatic Design Principles
Authors: Chen X. B. , Kai J. , Hashemi M.
Published: May 2007

Fluid dispensing systems have been widely employed in industry, by which fluid materials are delivered in a controllable manner. Currently, various designs of fluid dispensing systems exist; however, there is a lack of evaluating and comparing these different designs on a common base. This paper presents such an evaluation by means of axiomatic design principles. In particular, existing designs of dispensing systems are illustrated as decoupled and redundant ones based on the models available in the literature; and the information content of each design is calculated by using the algorithm specially developed in this paper for redundant designs. The results from such an evaluation will not only allow users to choose the appropriate systems for given applications, but will also facilitate designers to develop new dispensing systems.
Determination of Singularity-Free Zones in the Workspace of Planar 3-P̱RR Parallel Mechanisms
Authors: Masouleh Mehdi Tale , Gosselin Clément
Published: May 2007

This paper presents an algorithm for the determination of singularity-free zones in the workspace of the planar 3-P̱RR mechanism. The mathematical derivation of the algorithm is first given. Numerical examples are then included to demonstrate the application of the proposed approach.
Gas Hydrate Decomposition Rate in Flowing Water
Authors: Hamaguchi Ryokichi , Nishimura Yuki , Inoue Gen , Matsukuma Yosuke , Minemoto Masaki
Published: May 2007

The development of methane hydrate (MH), which exists under the ocean floor, has recently been brought to public attention. However, the production technology has not yet been established. It is important to understand the decomposition phenomenon of MH for an investigation of the safety and the profitability of production systems. In this research, the gas hydrate decomposition rate in flowing water was measured using HCFC141b hydrate as a substitute for MH. When the water temperature was higher than the boiling point of the decomposition gas, it was observed that the decomposition gas increased the decomposition rate. Moreover, the decomposition phenomenon was simulated by the lattice gas automaton method in order to establish the technique which analytically estimates the decomposition rate. The validity of the simulation method was shown by comparing the experiments. Furthermore, the formula between Reynolds number and Nusselt number was obtained, which express the heat transfer around the gas hydrate lump.
Modeling of a Coal-Fired Natural Circulation Boiler
Authors: Bhambare K. S. , Mitra Sushanta K. , Gaitonde U. N.
Published: May 2007

Modeling of a natural circulation boiler for a coal-fired thermal power station is presented here. The boiler system is divided into seven subcomponents, and for each section, models based on conservation of mass, momentum, and energy are formulated. The pressure drop at various sections and the heat transfer coefficients are computed using empirical correlations. Solutions are obtained by using SIMULINK. The model is validated by comparing its steady state and dynamic responses with the actual plant data. Open loop responses of the model to the step changes in the operating parameters, such as pressure, temperature, steam flow, feed water flow, are also analyzed. The present model can be used for the development and design of effective boiler control systems.
Multilocus Sequence Analysis Reveals that
Vibrio harveyi
and
V. campbellii
Are Distinct Species
Authors: Thompson Fabiano L. , Gomez-Gil Bruno , Vasconcelos Ana Teresa Ribeiro , Sawabe Tomoo
Published: May 2007

Identification and classification of
Vibrio
species have relied upon band pattern methods (e.g., amplified fragment length polymorphism) and DNA-DNA hybridization. However, data generated by these methods cannot be used to build an online electronic taxonomy. In order to overcome these limitations, we developed the first standard multilocus sequence scheme focused on the ubiquitous and pathogenic
Vibrio harveyi
species group (i.e.,
V. harveyi
,
V. campbellii
,
V. rotiferianus
, and a new as yet unnamed species). We examined a collection of 104 isolates from different geographical regions and hosts using segments of seven housekeeping genes. These two species formed separated clusters on the basis of
topA
,
pyrH
,
ftsZ
, and
mreB
gene sequences. The phylogenetic picture obtained by the other three loci, i.e.,
gyrB
,
recA
, and
gapA
, was more complex though.
V. campbellii
appeared nested within
V. harveyi
in the
recA
trees, whereas
V. harveyi
formed a tight nested cluster within
V. campbellii
by
gapA
. The
gyrB
gene had no taxonomic resolution and grouped the two species together. The fuzziness observed in these three genes seems not be related to recombination but to low divergence due to the accumulation of only a few substitutions. In spite of this, the concatenated sequences provided evidence that the two species form two separated clusters. These clusters did not arise by recombination but by accumulation of point mutations.
V. harveyi
and
V. campbellii
isolates can be readily identified through the open database resource developed in this study (
http://www.taxvibrio.lncc.br/
). We argue that the species should be defined by evolutionary criteria. Strains of the same species will share at least 95% concatenated sequence similarity using the seven loci, and, most importantly, cospecific strains will form cohesive readily recognizable phylogenetic clades.