bluuebunny/crossref_metadata_2025 huggingface dataset:
Exercise intensity‐dependent contribution of β‐adrenergic receptor‐mediated vasodilatation in hypoxic humans
Authors: Wilkins Brad W. , Pike Tasha L. , Martin Elizabeth A. , Curry Timothy B. , Ceridon Maile L. , Joyner Michael J.
Published: November 2007

We previously reported that hypoxia‐mediated reductions in α‐adrenoceptor sensitivity do not explain the augmented vasodilatation during hypoxic exercise, suggesting an enhanced vasodilator signal. We hypothesized that β‐adrenoceptor activation contributes to augmented hypoxic exercise vasodilatation. Fourteen subjects (age: 29 ± 2 years) breathed hypoxic gas to titrate arterial O2 saturation (pulse oximetry) to 80%, while remaining normocapnic via a rebreath system. Brachial artery and antecubital vein catheters were placed in the exercising arm. Under normoxic and hypoxic conditions, baseline and incremental forearm exercise (10% and 20% of maximum) was performed during control (saline), α‐adrenoceptor inhibition (phentolamine), and combined α‐ and β‐adrenoceptor inhibition (phentolomine/propranolol). Forearm blood flow (FBF), heart rate, blood pressure, minute ventilation, and end‐tidal CO2 were determined. Hypoxia increased heart rate (P < 0.05) and minute ventilation (P < 0.05) at rest and exercise under all drug infusions, whereas mean arterial pressure was unchanged. Arterial adrenaline (P < 0.05) and venous noradrenaline (P < 0.05) were higher with hypoxia during all drug infusions. The change (Δ) in FBF during 10% hypoxic exercise was greater with phentolamine (Δ306 ± 43 ml min−1) vs. saline (Δ169 ± 30 ml min−1) or combined phentolamine/propranolol (Δ213 ± 25 ml min−1; P < 0.05 for both). During 20% hypoxic exercise, ΔFBF was greater with phentalomine (Δ466 ± 57 ml min−1; P < 0.05) vs. saline (Δ346 ± 40 ml min−1) but was similar to combined phentolamine/propranolol (Δ450 ± 43 ml min−1). Thus, in the absence of overlying vasoconstriction, the contribution of β‐adrenergic mechanisms to the augmented hypoxic vasodilatation is dependent on exercise intensity.
Spike timing‐dependent plasticity: a learning rule for dendritic integration in rat CA1 pyramidal neurons
Authors: Campanac Emilie , Debanne Dominique
Published: November 2007

Long‐term plasticity of dendritic integration is induced in parallel with long‐term potentiation (LTP) or depression (LTD) based on presynaptic activity patterns. It is, however, not clear whether synaptic plasticity induced by temporal pairing of pre‐ and postsynaptic activity is also associated with synergistic modification in dendritic integration. We show here that the spike timing‐dependent plasticity (STDP) rule accounts for long‐term changes in dendritic integration in CA1 pyramidal neurons in vitro. Positively correlated pre‐ and postsynaptic activity (delay: +5/+50 ms) induced LTP and facilitated dendritic integration. Negatively correlated activity (delay: −5/−50 ms) induced LTD and depressed dendritic integration. These changes were not observed following positive or negative pairing with long delays (> ±50 ms) or when NMDA receptors were blocked. The amplitude–slope relation of the EPSP was facilitated after LTP and depressed after LTD. These effects could be mimicked by voltage‐gated channel blockers, suggesting that the induced changes in EPSP waveform involve the regulation of voltage‐gated channel activity. Importantly, amplitude–slope changes induced by STDP were found to be input specific, indicating that the underlying changes in excitability are restricted to a limited portion of the dendrites. We conclude that STDP is a common learning rule for long‐term plasticity of both synaptic transmission and dendritic integration, thus constituting a form of functional redundancy that insures significant changes in the neuronal output when synaptic plasticity is induced.
A Generalized Neural Network Model of Refrigerant Mass Flow Through Adiabatic Capillary Tubes and Short Tube Orifices
Authors: Zhao Ling-Xiao , Zhang Chun-Lu , Shao Liang-Liang , Yang Liang
Published: November 2007

Adiabatic capillary tubes and short tube orifices are widely used as expansive devices in refrigeration, residential air conditioners, and heat pumps. In this paper, a generalized neural network has been developed to predict the mass flow rate through adiabatic capillary tubes and short tube orifices. The input/output parameters of the neural network are dimensionless and derived from the homogeneous equilibrium flow model. Three-layer backpropagation (BP) neural network is selected as a universal function approximator. Log sigmoid and pure linear transfer functions are used in the hidden layer and the output layer, respectively. The experimental data of R12, R22, R134a, R404A, R407C, R410A, and R600a from the open literature covering capillary and short tube geometries, subcooled and two-phase inlet conditions, are collected for the BP network training and testing. Compared with experimental data, the overall average and standard deviations of the proposed neural network are 0.75% and 8.27% of the measured mass flow rates, respectively.
Stellar Feedback in Dwarf Galaxy Formation
Authors: Mashchenko Sergey , Wadsley James , Couchman H. M. P.
Published: November 2007

Dwarf galaxies pose substantial challenges for cosmological models. In particular, current models predict a dark-matter density that is divergent at the center, which is in sharp contrast with observations that indicate a core of roughly constant density. Energy feedback, from supernova explosions and stellar winds, has been proposed as a major factor shaping the evolution of dwarf galaxies. We present detailed cosmological simulations with sufficient resolution both to model the relevant physical processes and to directly assess the impact of stellar feedback on observable properties of dwarf galaxies. We show that feedback drives large-scale, bulk motions of the interstellar gas, resulting in substantial gravitational potential fluctuations and a consequent reduction in the central matter density, bringing the theoretical predictions in agreement with observations.
Physiotherapists' use of information in identifying a concussion: an extended Delphi approach
Authors: Sullivan S J , Schneiders A G , McCrory P , Gray A
Published: November 2007

Objective:

To determine the relative importance of signs and symptoms that a selected cohort of sports physiotherapists use to identify a sports concussion.

Methods:

A two-round Delphi methodology was used to achieve consensus in a cohort of 21 sports physiotherapists. A subsequent round involving an educational intervention provided the participants with an opportunity to modify their knowledge base through the provision of a relevant resource article.

Results:

Participants provided 123 responses, which were grouped into eight descriptive categories with consensus (>80%) being reached for the importance of: cognition/orientation, memory, motor dysfunction and state of consciousness. The category “state of consciousness” remained the most important information source at the completion of the study.

Conclusion:

Participants placed considerable importance on the player’s level of consciousness in their decision making. This would appear to be in conflict with recent trends to place greater importance on the role of symptoms in identifying a concussion.
Walking and primary prevention: a meta-analysis of prospective cohort studies
Authors: Hamer M , Chida Y
Published: November 2007

Objective:

To quantify the association between walking and the risk of cardiovascular disease (CVD) and all-cause mortality in healthy men and women.

Data sources:

Medline, Cochrane Database of Systematic Reviews, and Web of Science databases were searched to May 2007.

Study selection:

Prospective epidemiological studies of walking and CVD and all-cause mortality.

Results:

18 prospective studies were included in the overall analysis, which incorporated 459 833 participants free from CVD at baseline with 19 249 cases at follow-up. From the meta-analysis the pooled hazard ratio of CVD in the highest walking category compared with the lowest was 0.69, (95% CI 0.61 to 0.77, p<0.001), and 0.68 (0.59 to 0.78, p<0.001) for all-cause mortality. These effects were robust among men and women, although there was evidence of publication biases for the associations with CVD risk. Walking pace was a stronger independent predictor of overall risk compared with walking volume (48% versus 26% risk reductions, respectively). There was also evidence of a dose–response relationship across the highest, intermediate, and lowest walking categories in relation to the outcome measures.

Conclusions:

The results suggest walking is inversely associated with clinical disease endpoints and largely support the current guidelines for physical activity. The mechanisms that mediate this relationship remain largely unknown and should be the focus of future research.
Decrease of body fat during an ultra-endurance triathlon is associated with race intensity
Authors: Knechtle Beat , Schwanke Maike , Knechtle Patrizia , Kohler Goetz
Published: November 2007

OBJECTIVE:We investigated in a non-stop ultra-endurance triathlon, whether adipose subcutaneous tissue or skeletal muscle mass decreased.DESIGN:Descriptive field study.SETTING:The Triple Iron Triathlon Germany 2006 in Lensahn over 11.6 km swimming, 540 km cycling and 126.6 km running.SUBJECTS:17 male Caucasian triathletes (mean ± SD, age 39.2 ± 7.5 years, body mass 80.7 ± 8.9 kg, body height 178 ± 5 cm, BMI 25.4 ± 2.4 kg/m2).INTERVENTIONS:None.MAIN OUTCOME MEASUREMENTS:Determination of body mass, skin fold thicknesses, circumferences of extremities as well as calculation of body mass index (BMI), skeletal muscle mass and percent body fat in order to show changes after the race.RESULTS:A statistically significant decrease was shown for body mass (p<0.001), BMI (p<0.001) and calculated percent body fat (p<0.001) whereas skeletal muscle mass did not change statistically significantly (p>0.05). Circumferences of thigh, upper arm and calf did not decrease statistically significantly (p>0.05) whereas all skin fold thickness decreased statistically significantly (p<0.05) with exception of chest and thigh. A statistically significant correlation was found between the loss of percent body fat and the loss of body mass (p<0.01, r2=0.55) as well as ∆ percent body fat with race performance (p<0.05, r2=0.24).CONCLUSIONS:Ultra-triathletes at the Triple Iron Triathlon Germany 2006 showed a statistically significant decrease of body mass and percent body fat, where decrease of percent body fat was associated with race intensity.
Evaluating SafeClub: can risk management training improve the safety activities of community soccer clubs?
Authors: Abbott K , Klarenaar P , Donaldson A , Sherker S
Published: November 2007

Objective:

To evaluate a sports safety-focused risk-management training programme.

Design:

Controlled before and after test.

Setting:

Four community soccer associations in Sydney, Australia.

Participants:

76 clubs (32 intervention, 44 control) at baseline, and 67 clubs (27 intervention, 40 control) at post-season and 12-month follow-ups.

Intervention:

SafeClub, a sports safety-focused risk-management training programme (3×2 hour sessions) based on adult-learning principles and injury-prevention concepts and models.

Main outcome measures:

Changes in mean policy, infrastructure and overall safety scores as measured using a modified version of the Sports Safety Audit Tool.

Results:

There was no significant difference in the mean policy, infrastructure and overall safety scores of intervention and control clubs at baseline. Intervention clubs achieved higher post-season mean policy (11.9 intervention vs 7.5 controls), infrastructure (15.2 vs 10.3) and overall safety (27.0 vs 17.8) scores than did controls. These differences were greater at the 12-month follow-up: policy (16.4 vs 7.6); infrastructure (24.7 vs 10.7); and overall safety (41.1 vs 18.3). General linear modelling indicated that intervention clubs achieved statistically significantly higher policy (p<0.001), infrastructure (p<0.001) and overall safety (p<0.001) scores compared with control clubs at the post-season and 12-month follow-ups. There was also a significant linear interaction of time and group for all three scores: policy (p<0.001), infrastructure (p<0.001) and overall safety (p<0.001).

Conclusions:

SafeClub effectively assisted community soccer clubs to improve their sports safety activities, particularly the foundations and processes for good risk-management practice, in a sustainable way.
Autonomic and behavioural thermoregulation in tennis
Authors: Morante S M , Brotherhood J R
Published: November 2007

Objectives:

This report describes physiological and behavioural mechanisms behind the control of body temperature and thermal comfort during competitive singles tennis.

Methods:

Thermoregulatory responses and workload were observed during “best of three sets” tennis matches among 25 players. In total, 94 matches were played in ambient temperatures ranging from 14.5 to 38.4°C. The thermal environment was assessed by dry bulb, wet bulb and natural wet bulb temperatures, globe temperature and wind speed. Core body and skin temperatures were recorded each minute throughout the match, and body mass and fluid intake were measured before the match, after 30 minutes of play and at the completion of the match to determine sweat rate. Subjective ratings of thermal strain included thermal comfort, sweatiness and perceived exertion. Workload observations included match, game and point durations, and the proportion of match time spent in play (effective playing time).

Results:

Change in rectal temperature was positively correlated with point duration (p<0.001) and effective playing time (p<0.05). Sweat rate showed positive associations with air (p<0.0001), rectal (p<0.03) and skin (p<0.0001) temperature. Thermal comfort was reduced with increasing rectal (p<0.03) and skin (p<0.0001) temperature. Point duration and effective playing time were reduced when conditions were rated increasingly difficult (p<0.002 and p<0.0002, respectively).

Conclusion:

Autonomic (increase in sweat rate) and behavioural (reduction in workload) thermoregulation are responsible for the control of body temperature and thermal comfort during tennis.
Joint Loading Modality: Its Application to Bone Formation and Fracture Healing
Authors: Zhang Ping , Malacinski George , Yokota Hiroki
Published: November 2007

Sports related injuries such as impact and stress fractures often require a rehabilitation program to stimulate bone formation and accelerate fracture healing. This review introduces a recently developed joint loading modality and evaluates its potential applications to bone formation and fracture healing in post-injury rehabilitation. Bone is a dynamic tissue whose structure is constantly altered in response to its mechanical environments. Indeed, many loading modalities can influence the bone remodeling process. The joint loading modality is, however, able to enhance anabolic responses and accelerate wound healing without inducing significant in situ strain at the site of bone formation or fracture healing. This review highlights the unique features of this loading modality and discusses its potential underlying mechanisms as well as possible clinical applications.
The secret art of managing healthcare expenses: investigating implicit rationing and autonomy in public healthcare systems
Authors: Lauridsen S M R , Norup M S , Rossel P J H
Published: November 2007

Rationing healthcare is a difficult task, which includes preventing patients from accessing potentially beneficial treatments. Proponents of implicit rationing argue that politicians cannot resist pressure from strong patient groups for treatments and conclude that physicians should ration without informing patients or the public. The authors subdivide this specific programme of implicit rationing, or “hidden rationing”, into local hidden rationing, unsophisticated global hidden rationing and sophisticated global hidden rationing. They evaluate the appropriateness of these methods of rationing from the perspectives of individual and political autonomy and conclude that local hidden rationing and unsophisticated global hidden rationing clearly violate patients’ individual autonomy, that is, their right to participate in medical decision-making. While sophisticated global hidden rationing avoids this charge, the authors point out that it nonetheless violates the political autonomy of patients, that is, their right to engage in public affairs as citizens. A defence of any of the forms of hidden rationing is therefore considered to be incompatible with a defence of autonomy.
Elderly patients also have rights
Authors: Pérez-Cárceles M D , Lorenzo M D , Luna A , Osuna E
Published: November 2007

Background:

Sharing information with relatives of elderly patients in primary care and in hospital has to fit into the complex set of obligations, justifications and pressures concerning the provision of information, and the results of some studies point to the need for further empirical studies exploring issues of patient autonomy, privacy and informed consent in the day-to-day care of older people.

Objectives:

To know the frequency with which “capable” patients over 65 years of age receive information when admitted to hospital, the information offered to the families concerned, the person who gives consent for medical intervention, and the degree of satisfaction with the information received and the healthcare provided.

Method:

A descriptive questionnaire given to 200 patients and 200 relatives during the patients’ stay in hospital.

Results:

Only 5% of patients confirmed that they had been asked whether information could be given to their relatives. A significantly higher proportion of relatives received information on the successive stages of the care offered than did patients themselves. As the age of the patients increased, so the number who were given information, understood the information and were asked for their consent for complementary tests decreased. The degree of satisfaction with the information offered was high for both patients and relatives (86.5% and 84%, respectively), despite the irregularities observed.

Conclusions:

The capacity of elderly patients to participate in the decision-making process is frequently doubted simply because they have reached a certain age and it is thought that relatives should act as their representatives. In Spain, the opinion of the family and doctors appears to play a larger role in making decisions than does the concept of patient autonomy.
Vertical migration in adult Atlantic cod (Gadus morhua)
Authors: Strand Espen , Huse Geir
Published: November 2007

We investigate the trade-offs associated with vertical migration and swimming speed of Atlantic cod (Gadus morhua) using an adaptive individual-based model. Simulations with varying distribution and occurrence of prey, with and without swimbladder constraints, and visual predation were performed. Most simulations resulted in cod migrations between the bottom and pelagic zones. In simulations with high probability of encountering pelagic prey, the cod spent the daytime in the pelagic zone, moving to the bottom to feed only when no pelagic prey were encountered. At night the cod stayed in the pelagic zone to attain neutral buoyancy. In simulations with low occurrence of pelagic prey or high visual predation pressure, the cod remained at the bottom feeding on the consistently present benthic prey. If the pelagic prey occurred far above the sea floor or there were no benthic prey, the cod abandoned all bottom contact. The study thus predicts that the probability of encountering energy-rich pelagic prey is the key factor in driving vertical migration in adult cod. Buoyancy regulation is further shown to be an important constraint on vertical migration.
Genome size and genome evolution in diploid Triticeae species
Authors: Eilam T. , Anikster Y. , Millet E. , Manisterski J. , Sagi-Assif O. , Feldman M.
Published: November 2007

One of the intriguing issues concerning the dynamics of plant genomes is the occurrence of intraspecific variation in nuclear DNA amount. The aim of this work was to assess the ranges of intraspecific, interspecific, and intergeneric variation in nuclear DNA content of diploid species of the tribe Triticeae (Poaceae) and to examine the relation between life form or habitat and genome size. Altogether, 438 plants representing 272 lines that belong to 22 species were analyzed. Nuclear DNA content was estimated by flow cytometry. Very small intraspecific variation in DNA amount was found between lines of Triticeae diploid species collected from different habitats or between different morphs. In contrast to the constancy in nuclear DNA amount at the intraspecific level, there are significant differences in genome size between the various diploid species. Within the genus Aegilops , the 1C DNA amount ranged from 4.84 pg in A. caudata to 7.52 pg in A. sharonensis; among genera, the 1C DNA amount ranged from 4.18 pg in Heteranthelium piliferum to 9.45 pg in Secale montanum . No evidence was found for a smaller genome size in annual, self-pollinating species relative to perennial, cross-pollinating ones. Diploids that grow in the southern part of the group’s distribution have larger genomes than those growing in other parts of the distribution. The contrast between the low variation at the intraspecific level and the high variation at the interspecific one suggests that changes in genome size originated in close temporal proximity to the speciation event, i.e., before, during, or immediately after it. The possible effects of sudden changes in genome size on speciation processes are discussed.
Microsatellite-based characterization of the Castanea sativa cultivar heritage of southern Switzerland
Authors: Gobbin Davide , Hohl Leandro , Conza Lisa , Jermini Mauro , Gessler Cesare , Conedera Marco
Published: November 2007

Southern Switzerland has a long tradition of chestnut cultivation as a staple food. Local inhabitants constantly selected varieties according to the ripening period, the type of use, and the adaptability to the territory. As a result, the panorama of chestnut varieties is very complex, as reflected by more than 120 different variety names in an area of 26 000 ha. Since 1994, 47 varieties have been conserved in the chestnut germplasm of southern Switzerland (CSS), including Marroni, Euro-Japanese, and French varieties. A selection of 164 individuals from the CSS was analysed by 8 SSR markers (4 of which were developed in this study). Microsatellite analysis indicated that the CSS was accurately established, as 86% of the individuals grafted were correctly labeled. The identification of 98 genotypes, 10 clonal chestnut groups, 4 synonym groups, and 12 homonym groups reflected the complex ethnogeographical structure of the chestnut distribution. The 17 Marroni individuals considered clustered in 2 differentiated genetic groups instead of only 1 as expected. The fundamental problem of the frequent cases of homonymy and synonymy is discussed, as is the need for criteria for discriminating between polyclonal varieties and distinct homonymous varieties.
Type 2 diabetes mellitus, resistance training, and innate immunity: is there a common link?
Authors: DiPenta Jennifer M. , Green-Johnson Julia M. , Murphy René J.L.
Published: November 2007

Type 2 diabetes mellitus is a serious chronic disease that is very prevalent in the developed world. The etiology of this disease is not well understood. Recently, the role of the innate immune system in the pathogenesis of type 2 diabetes and its complications has received a great deal of attention. Cytokines, acute phase proteins, and phagocytes have been implicated in this model. Resistance training has known benefits in type 2 diabetic patients and older adults, such as improved insulin action, insulin sensitivity, fasting blood glucose and insulin, and glucose tolerance levels. Actions of pro-inflammatory mediators linked to dysregulated innate immune activity have been associated with type 2 diabetes. The immunomodulatory effects of exercise, and in particular approaches such as resistance training, may provide a strategy to counter these pro-inflammatory effectors. However, the effects of resistance training on innate immunity have not been studied extensively in adults with type 2 diabetes or in older adults who are at increased risk for development of type 2 diabetes. This review discusses the possibility that resistance training may have positive effects on innate immunity in this population and so may provide benefits in addition to improving strength and functional abilities. In particular, the potential of resistance training to modulate pro-inflammatory parameters associated with type 2 diabetes, as a strategy that could provide multiple beneficial health outcomes, is addressed.
Ageing and physical activity: evidence to develop exercise recommendations for older adultsThis article is part of a supplement entitled Advancing physical activity measurement and guidelines in Canada: a scientific review and evidence-based foundation for the future of Canadian physical activity guidelines co-published by Applied Physiology, Nutrition, and Metabolism and the Canadian Journal of Public Health. It may be cited as Appl. Physiol. Nutr. Metab. 32(Suppl. 2E) or as Can. J. Public Health 98(Suppl. 2).
Authors: Paterson Donald H. , Jones Gareth R. , Rice Charles L.
Published: November 2007

An abundance of epidemiological research confirms the benefits of physical activity in reducing risk of various age-related morbidities and all-cause mortality. Analysis of the literature focusing on key exercise variables (e.g., intensity, type, and volume) suggests that the requisite beneficial amount of activity is that which engenders improved cardiorespiratory fitness, strength, power, and, indirectly, balance. Age-related declines in these components are such that physical limitations impinge on functional activities of daily living. However, an exercise programme can minimize declines, thus preventing older adults (age 65+ years) from crossing functional thresholds of inability. Cross-sectional and longitudinal data demonstrate that cardiorespiratory fitness is associated with functional capacity and independence; strength and, importantly, power are related to performance and activities of daily living; and balance-mobility in combination with power are important factors in preventing falls. Exercise interventions have documented that older adults can adapt physiologically to exercise training, with gains in functional capacities. The few studies that have explored minimal or optimal activity requirements suggest that a threshold (intensity) within the moderately vigorous domain is needed to achieve and preserve related health benefits. Thus, physical activity and (or) exercise prescriptions should emphasize activities of the specificity and type to improve components related to the maintenance of functional capacity and independence; these will also delay morbidity and mortality. An appropriate recommendation for older adults includes moderately vigorous cardiorespiratory activities (e.g., brisk walking), strength and (or) power training for maintenance of muscle mass and specific muscle-group performance, as well as “balance-mobility practice” and flexibility (stretching) exercise as needed.
Chemical and mechanical adaptations of the respiratory system at rest and during exercise in human pregnancy
Authors: Jensen Dennis , Webb Katherine A. , O’Donnell Denis E.
Published: November 2007

Human pregnancy is characterized by significant increases in ventilatory drive both at rest and during exercise. The increased ventilation and attendant hypocapnia of pregnancy has been attributed primarily to the stimulatory effects of female sex hormones (progesterone and estrogen) on central and peripheral chemoreflex drives to breathe. However, recent research from our laboratory suggests that hormone-mediated increases in neural (or non-chemoreflex) drives to breathe may contribute importantly to the hyperventilation of pregnancy. This review challenges traditional views of ventilatory control, and outlines an alternative hypothesis of the control of breathing during human pregnancy that is currently being tested in our laboratory. Conventional wisdom suggests that pregnancy-induced increases in central respiratory motor output command in combination with progressive thoraco–abdominal distortion may compromise the normal mechanical response of the respiratory system to exercise, increase the perception of exertional breathlessness, and curtail aerobic exercise performance in otherwise healthy pregnant women. The majority of available evidence suggests, however, that neither pregnancy nor advancing gestation are associated with reduced aerobic working capacity or increased breathlessness at any given work rate or ventilation during exhaustive weight-supported exercise.
Incidental movement, lifestyle-embedded activity and sleep: new frontiers in physical activity assessmentThis article is part of a supplement entitled Advancing physical activity measurement and guidelines in Canada: a scientific review and evidence-based foundation for the future of Canadian physical activity guidelines co-published by Applied Physiology, Nutrition, and Metabolism and the Canadian Journal of Public Health. It may be cited as Appl. Physiol. Nutr. Metab. 32(Suppl. 2E) or as Can. J. Public Health 98(Suppl. 2).
Authors: Tremblay Mark S. , Esliger Dale W. , Tremblay Angelo , Colley Rachel
Published: November 2007

Canadian public health messages relating to physical activity have historically focused on the prescription of purposeful exercise, most often assessing leisure-time physical activity (LTPA). Although LTPA contributes to total energy expenditure (TEE), a large part of the day remains neglected unless one also considers the energy expended outside of purposeful exercise. This paper reviews the potential impact of incidental (non-exercise or non-purposeful) physical activity and lifestyle-embedded activities (chores and incidental walking) upon TEE and indicators of health. Given that incidental movement occurs sporadically throughout the day, this form of energy expenditure is perhaps most vulnerable to increasingly ubiquitous mechanization and automation. The paper also explores the relationship of physical inactivity, including sleep, to physical activity, TEE, and health outcomes. Suggestions are provided for a more comprehensive physical activity recommendation that includes all components of TEE. Objective physical activity monitors with time stamps are considered as a better means to capture and examine human movements over the entire day.
Lipoprotein electrostatic properties regulate hepatic lipase association and activity
Authors: Boucher Jonathan G. , Nguyen Trang , Sparks Daniel L.
Published: November 2007

The effect of lipoprotein electrostatic properties on the catalytic regulation of hepatic lipase (HL) was investigated. Enrichment of serum or very low density lipoprotein (VLDL) with oleic acid increased lipoprotein negative charge and stimulated lipid hydrolysis by HL. Similarly, enrichment of serum or isolated lipoproteins with the anionic phospholipids phosphatidylinositol (PI), phosphatidic acid, or phosphatidylserine also increased lipoprotein negative charge and stimulated hydrolysis by HL. Anionic lipids had a small effect on phospholipid hydrolysis, but significantly stimulated triacylglyceride (TG) hydrolysis. High density lipoprotein (HDL) charge appears to have a specific effect on lipolysis. Enrichment of HDL with PI significantly stimulated VLDL-TG hydrolysis by HL. To determine whether HDL charge affects the association of HL with HDL and VLDL, HL–lipoprotein interactions were probed immunochemically. Under normal circumstances, HL associates with HDL particles, and only small amounts bind to VLDL. PI enrichment of HDL blocked the binding of HL with HDL. These data indicate that increasing the negative charge of HDL stimulates VLDL-TG hydrolysis by reducing the association of HL with HDL. Therefore, HDL controls the hydrolysis of VLDL by affecting the interlipoprotein association of HL. Lipoprotein electrostatic properties regulate lipase association and are an important regulator of the binding and activity of lipolytic enzymes.
Microwave-assisted one-pot synthesis of some new furo[2,3-b]quinolines using potassium carbonate under solvent-free conditions
Authors: Raghavendra M , Naik Halehatty S. Bhojya , Sherigara Bailure S
Published: November 2007

A rapid, solvent-free microwave-assisted method has been developed for the synthesis of novel furo quinolines. The title compounds were achieved by the reaction between corresponding 2-hydroxy-3-formyl-quinolines (1a–1c) with chloroacetamide, ethylchloroacetate, and phenacylbromide in specially designed microwave (MW) oven for organic synthesis in unsealed borosil vessel in presence of potassium carbonate. In this method, isolation is accomplished by just treating the reaction mixture with water, and products were obtained in high yield. Hence, this method was found to be very effective and ecofriendly. The structure of the newly synthesized compounds has been evaluated on the basis of analytical, IR, 1H NMR, and mass spectral data.Key words: furoquinoline, microwave irradiation, potassium carbonate, solvent-free conditions.
ORGANIC CHUA'S CIRCUIT
Authors: FORTUNA LUIGI , FRASCA MATTIA , UMANA ELENA , LA ROSA MANUELA , NICOLOSI DONATA , SICURELLA GIOVANNI
Published: November 2007

In this paper, an entire organic Chua's circuit is presented. The adopted technology is one of the most advanced in the post-silicon era and extends the applications of classical silicon devices. The electronic circuit design is based on Organic Thin-Film Transistors (OTFTs). New electronic blocks based on OTFT are designed to be suitable with the organic technology features. Typical dynamics of the Chua's circuit have been reproduced.
GENERATION OF COMPLEX STOCHASTIC TEXTURES USING CELLULAR NEURAL NETWORKS
Authors: ŚLOT KRZYSZTOF , KORNATOWSKI ŁUKASZ , DȨBIEC PIOTR , KIM HYONGSUK
Published: November 2007

The following paper explores possibilities of an application of Cellular Neural Networks for spontaneous generation of complex stochastic textures. The considered class of textures includes images, which are combinations of large-scale and fine-scale stochastic patterns. Accurate modeling of properties of such complex stochastic fields by means of a single 1-neighborhood CNN poses great difficulties. Therefore, we propose a method that exploits texture decomposition into two elements and involves an application of two networks, designated for performing distinct partial tasks. The first step of the proposed CNN-based texture generation procedure focuses on modeling of a coarse, large-scale textural pattern. The second step refines this pattern into a final image that is expected to closely imitate a target texture.
THE NONLINEAR MASLOV INDEX AND THE CALABI HOMOMORPHISM
Authors: SIMON GABI BEN
Published: November 2007

In this paper, we find that the asymptotic nonlinear Maslov index defined on the universal cover of the group of all contact Hamiltonian diffeomorphisms of the standard (2n - 1)-dimensional contact sphere is a quasimorphism. Then we show our main result: Let M be standard (n - 1)-dimensional complex projective space. We prove that the value of the pullback of the asymptotic nonlinear Maslov index to the universal cover of the group of Hamiltonian diffeomorphisms of M, when evaluated on a diffeomorphism supported in a sufficiently small open subset of M, equals [Formula: see text] times the Calabi invariant of this diffeomorphism.
MINIMAL ATLASES OF CLOSED SYMPLECTIC MANIFOLDS
Authors: RUDYAK YU. B. , SCHLENK FELIX
Published: November 2007

We study the number of Darboux charts needed to cover a closed connected symplectic manifold (M, ω) and effectively estimate this number from below and from above in terms of the Lusternik–Schnirelmann category of M and the Gromov width of (M, ω).
FUZZY RULE-BASED ENHANCING KEY DISSEMINATION METHOD FOR THE DYNAMIC FILTERING-BASED SENSOR NETWORKS
Authors: KIM BYUNG HEE , LEE HAE YOUNG , CHO TAE HO
Published: November 2007

A secure mechanism is needed to use sensor nodes in real world, since we cannot anticipate attack types. Yu and Guan proposed the dynamic en-route filtering scheme (DEF) to detect and drop false reports as soon as possible in wireless sensor networks. In this scheme, the choice of a threshold value to diffuse keys is important since it represents a trade-off between detection power and overhead. A large threshold value can increase the probability of detecting false reports but it consumes too much energy during the key dissemination phase. Thus, we should choose a threshold value to optimize between the detection power and energy consumption. In this paper we propose a key dissemination limiting method to diffuse keys efficiently. The threshold value in the proposed method is determined by a fuzzy rule-based system by considering the energy level of the network, the number of secret keys in a cluster, and the distance from the base station (BS) to a cluster head. The simulation results show that the proposed method can conserve energy, while it provides sufficient detection power.
Optimal parallel selection
Authors: Han Yijie
Published: November 2007

We present an optimal parallel selection algorithm on the EREW PRAM. This algorithm runs in
O
(log
n
) time with
n
/log
n
processors. This complexity matches the known lower bound for parallel selection on the EREW PRAM model. We therefore close this problem which has been open for more than a decade.
Edge-disjoint paths revisited
Authors: Chekuri Chandra , Khanna Sanjeev
Published: November 2007

The approximability of the maximum edge-disjoint paths problem (EDP) in directed graphs was seemingly settled by an Ω(
m
1/2
- ϵ)-hardness result of Guruswami et al. [2003], and an
O
(√
m
) approximation achievable via a natural multicommodity-flow-based LP relaxation as well as a greedy algorithm. Here
m
is the number of edges in the graph. We observe that the Ω(
m
1/2
- ϵ)-hardness of approximation applies to
sparse
graphs, and hence when expressed as a function of
n
, that is, the number of vertices, only an Ω(
n
1/2
- ϵ)-hardness follows. On the other hand,
O
(√
m
)-approximation algorithms do not guarantee a
sublinear
(in terms of
n
) approximation algorithm for
dense
graphs. We note that a similar gap exists in the known results on the integrality gap of the flow-based LP relaxation: an Ω(√
n
) lower bound and
O
(√
m
) upper bound. Motivated by this discrepancy in the upper and lower bounds, we study algorithms for EDP in directed and undirected graphs and obtain improved approximation ratios. We show that the greedy algorithm has an approximation ratio of
O
(min(
n
2/3
, √
m
)) in undirected graphs and a ratio of
O
(min(
n
4/5
, √
m
)) in directed graphs. For acyclic graphs we give an
O
(√
n
ln
n
) approximation via LP rounding. These are the first sublinear approximation ratios for EDP. The results also extend to EDP with weights and to the uniform-capacity unsplittable flow problem (UCUFP).
Energy-efficient algorithms for flow time minimization
Authors: Albers Susanne , Fujiwara Hiroshi
Published: November 2007

We study scheduling problems in battery-operated computing devices, aiming at schedules with low total energy consumption. While most of the previous work has focused on finding feasible schedules in deadline-based settings, in this article we are interested in schedules that guarantee good response times. More specifically, our goal is to schedule a sequence of jobs on a variable-speed processor so as to minimize the total cost consisting of the energy consumption and the total flow time of all jobs.

We first show that when the amount of work, for any job, may take an arbitrary value, then no online algorithm can achieve a constant competitive ratio. Therefore, most of the article is concerned with unit-size jobs. We devise a deterministic constant competitive online algorithm and show that the offline problem can be solved in polynomial time.
Local and global handovers based on in-band signaling in wireless ATM networks
Authors: Marsan M. Ajmone , Chiasserini C. F. , Fumagalli A. , Cigno R. Lo , Munafò M.
Published: November 2007

This paper illustrates a protocol for wireless ATM networks which makes use of in-band signaling, i.e., of ATM resource management cells, to process network handovers and guarantee the in-sequence and loss-free delivery of the ATM cells containing user data. The proposed approach aims at minimizing the necessary modifications of the ATM signaling standard required to superimpose user mobility onto the fixed network infrastructure, and provides for a gradual upgrade of the fixed network to handle mobility. The proposed protocol handles both local handovers, in which the connection access point needs not migrate to a new ATM local exchange, and global handovers, in which the connection access point must migrate to a new local exchange. The maximum buffering capacity necessary at the base station to guarantee in-sequence and loss-free cell delivery is estimated using a simple model that is studied by means of an ATM network simulation tool.
HomeRF™ and SWAP
Authors: Negus Kevin J. , Waters John , Tourrilhes Jean , Romans Chris , Lansford Jim , Hui Stephen
Published: November 2007

The Shared Wireless Aaccess Protocol (SWAP) specification for wireless voice and data networking within the home will enable a new class of mobile consumer devices that draw from the power and content of the Internet and the Home PC. If cable modems and xDSL represent the "last mile" access to the home, then HomeRFTM's mission with SWAP could be called the "very last 150 feet" within and around the home. HomeRFTM has the broad backing of the major corporate stakeholders for networking within the home and is optimized specifically for the cost/performance point needed for consumers. The technology leverages the existing PC-industry infrastructure around the Internet, TCP/IP and Ethernet and adds a standard way to connect to the Public Switched Telephone Network (PSTN) for voice telephony. First products should appear in late 1999 and future versions with enhanced features and/or higher data rates should follow by 1--2 years.
Mobile IP and the IETF
Authors: Perkins Charles E.
Published: November 2007

This is a report from your faithful IETF correspondent, covering some of the relevant events at the 42nd IETF conference in Chicago, IL. Milestones were reached, and promising new developments are taking shape. Chief among the milestones was the passage to Last Call of the mobility support protocol for IP version 6 (IPv6). New developments include accounting protocol extensions for Mobile IP, and interest forming around the possible convening of a BOF for IP and TCP over wireless links at the next IETF conference in December.
GloMo, July 1998
Authors: Ramanathan Ram
Published: November 2007

The Global Mobile Information Systems (GloMo) is a a multi-organization program funded by the U.S Defense Advanced Research Projects Agency (DARPA). The most recent GloMo Principal Investigators (PI) meeting was held in Washington D.C between July 28--30, 1998. As part of this meeting, a number of technologies developed within this program were demonstrated to a wide variety of audiences. In this article, we present a brief overview of the GloMo program and report on the July PI meeting, focusing on the demonstrations, and the technologies they represent.
Mobility management for large private wireless ATM installations
Authors: Kaloxylos Alexandros , Hansén Harri , Merakos Lazaros
Published: November 2007

New mobility management protocols that aim to support terminal movement, in wireless ATM Customer Premises Networks (CPN) are presented. The functionality of these protocols consists of the procedures for handover (i.e., re-routing of active data connections to a new radio cell) and the procedures for location management (i.e., storing and retrieving the exact location of a mobile terminal). In the considered CPN environment, the ATM switches communicate using the PNNI protocol, the routing functionality of which is used by the mobility management protocols to perform their tasks more efficiently.
Trespass, nuisance, and spam
Authors: Aalberts Robert J. , Poon Percy , Thistle Paul
Published: November 2007

Even in the instantaneous world of cyberspace, common law still provides a protective shield over many Internet problems.
Competing with IT
Authors: Ray Gautam , Muhanna Waleed A. , Barney Jay B.
Published: November 2007

Studying why some firms derive more competitive advantage and value than others using IT resources.
Effect of heterogeneous APD restitution on VF organization in a model of the human ventricles
Authors: Keldermann R. H. , ten Tusscher K. H. W. J. , Nash M. P. , Hren R. , Taggart P. , Panfilov A. V.
Published: November 2007

The onset of ventricular fibrillation (VF) has been associated with steep action potential duration restitution in both clinical and computational studies. Recently, detailed clinical restitution properties in cardiac patients were reported showing a substantial degree of heterogeneity in restitution slopes at the epicardium of the ventricles. The aim of the present study was to investigate the effect of heterogeneous restitution properties in a three-dimensional model of the ventricles using these clinically measured restitution data. We used a realistic model of the human ventricles, including detailed descriptions of cell electrophysiology, ventricular anatomy, and fiber direction anisotropy. We extended this model by mapping the clinically observed epicardial restitution data to our anatomic representation using a diffusion-based algorithm. Restitution properties were then fitted by regionally varying parameters of the electrophysiological model. We studied the effects of restitution heterogeneity on the organization of VF by analyzing filaments and the distributions of excitation periods. We found that the number of filaments and the excitation periods were both dependent on the extent of heterogeneity. An increased level of heterogeneity leads to a greater number of filaments and a broader distribution of excitation periods, thereby increasing the complexity and dynamics of VF. Restitution heterogeneity may play an important role in providing a substrate for cardiac arrhythmias.