bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclic steps and roll waves in shallow water flow over an erodible bed
Authors: Balmforth N. J. , Vakil A.
Published: February 2012

The St Venant equations in conjunction with a phenomenological law for erosion are used to explore the nonlinear dynamics of cyclic steps – linearly unstable bedform patterns which emerge when uniform flow over an erodible bed becomes supercritical. The instability saturates by blocking the overlying flow and creating hydraulic jumps just downstream of the steepest part of the steps. Near onset, steadily migrating, nonlinear step patterns are constructed and shown to suffer a short-wavelength secondary instability that ‘roughens’ the bed and renders the staircase patterns less regular and time-dependent. An eddy viscosity is needed to regularize both the onset of the primary steps and the secondary instabilities. Further beyond the critical Froude number, the steps block the flow sufficiently to arrest erosion significantly, creating complicated patterns mixing migrating steps and stationary bedforms. The reduction in flux also stabilizes roll waves – a second, hydrodynamic instability of uniform supercritical flow. It is further shown that roll waves are purely convective instabilities, whereas cyclic steps can be absolute. Thus, in the finite geometries of the laboratory or field, it may be difficult to excite roll waves. On the other hand, the complicated spatiotemporal patterns associated with the cyclic-step instability should develop naturally. The complicated patterns resulting from the secondary instability do not appear to have been observed experimentally, calling into question the validity of the model.
A fully adaptive wavelet-based approach to homogeneous turbulence simulation
Authors: De Stefano G. , Vasilyev O. V.
Published: February 2012

The ability of wavelet multi-resolution analysis to detect and track the energy-containing motions that govern the dynamics of a fluid flow offers a unique hierarchical framework for modelling and simulating turbulence. In this paper, the role of the wavelet thresholding level in wavelet-based modelling and simulation of turbulent flows is systematically examined. The thresholding level controls the relative importance of resolved energetic structures and residual unresolved background flow and, thus, the achieved turbulence resolution. A fully adaptive eddy capturing approach is developed that allows variable-fidelity numerical simulations of turbulence to be performed. The new method is based on wavelet filtering with time-varying thresholding. The thresholding level automatically adapts to the desired turbulence resolution during the simulation. The filtered governing equations supplemented by a localized dynamic energy-based closure model are solved numerically using the adaptive wavelet collocation method. The approach is successfully tested in the numerical simulation of both linearly forced and freely decaying homogeneous turbulence.
Habitat conditions and host tree properties affect the occurrence, abundance and fertility of the endangered lichenLobaria pulmonariain wooded meadows of Estonia
Authors: JÜRIADO Inga , KARU Leelia , LIIRA Jaan
Published: February 2012

We assessed multiple environmental factors that might influence the population vitality of the epiphytic lichenLobaria pulmonariaat the individual tree and habitat levels in partially overgrown wooded meadows in Estonia. A total of 301 trees of four species were sampled at nine study plots, using a stratified factorial scheme, 151 colonized byL. pulmonariaand 150 not colonized byL. pulmonariaforming the control group. We used the Generalized Linear Models (GLZ) to identify a complex of factors which predicts the probability of the lichen occurring on tree trunks and the presence of apothecia on its individuals. We employed the General Linear Mixed Model (GLMM) to study the relationship between cover ofL. pulmonariaand environmental factors. The occurrence probability ofL. pulmonariaon tree trunks increased with increasing light availability and height of deciduous shrubs near the trunk, and decreased with increasing distance to the nearest colonized tree. The host tree species and its trunk properties were also of importance, particularly the facilitating effect of the cover of bryophytes uponL. pulmonaria. The probability of occurrence of apothecia increased with maximum values of bark pH and cover ofL. pulmonariaon the trunk. We conclude that partially overgrown wooded meadows are suitable habitats forL. pulmonaria. However, to maintain the vitality of these populations, a specific management scheme, preventing development of a dense stand, should be applied. Management requirements would include 1) selective cutting of overgrowing coniferous trees (particularly spruce), 2) preservation of adult and younger potential host trees within 10–20 m of colonized trees, 3) preservation of scattered deciduous shrubs in the vicinity of the host trees.
The influence of health education on the prevalence of intestinal parasites in a low-income community of Campos dos Goytacazes, Rio de Janeiro State, Brazil
Authors: PEREIRA A. P. M. F. , ALENCAR M. F. L. , COHEN S. C. , SOUZA-JÚNIOR P. R. B. , CECCHETTO F. , MATHIAS L. S. , SANTOS C. P. , ALMEIDA J. C. A. , DE MORAES NETO A. H. A.
Published: February 2012

In a recent study by our group on the prevalence of intestinal parasitic infections and on the knowledge, attitudes and practices of local residents of Campos dos Goytacazes, Rio de Janeiro, Brazil, we observed that about 50% of the inhabitants were parasitized and had some knowledge of intestinal parasitic infections but did not apply this knowledge in daily practice. We were thus motivated to implement strategies in health education to promote preventive measures in the locality. The goal of the present work was to evaluate the influence of health education on the prevalence of intestinal parasitic infections in the region in an effort to strengthen public policies for controlling these diseases in Brazil. The methodology adopted was based on action-research and a theoretical framework of health promotion. Our results demonstrate that the study population exhibited an enhanced awareness of the importance of disease from intestinal parasitic infections. Attitudes and practices related to prevention were significantly improved after the shared health education. In conclusion, this study allowed the shared construction of knowledge that reflected the true needs of the residents.
High cold tolerance through four seasons and all free-living stages in an ectoparasite
Authors: HÄRKÖNEN LAURA , KAITALA ARJA , KAUNISTO SIRPA , REPO TAPANI
Published: February 2012

Off-host stages of temperate parasites must cope with low temperatures. Cold tolerance is often highest in winter, as a result of diapause and cold acclimation, and low during the active summer stages. In some blood-feeding ectoparasites, offspring provisioning determines cold tolerance through all the non-feeding, off-host stages. Large size increases survival in the cold, but so far seasonal variation in within-female offspring size has not been associated with offspring cold tolerance. The deer ked (Lipoptena cervi) reproduces on cervids from autumn to spring. Newborn pupae drop off the host, facing frosts without any acclimation. We examined cold tolerance through 4 seasons and from birth to adulthood by means of short- and long-term frost exposure. We expected females to produce more tolerant offspring in winter than in spring. Large spring pupae survived prolonged frosts better than did small winter pupae. Thus more tolerant offspring were not produced when the temperature outside the host is at its lowest. Unexpectedly, the freezing points were −20°C or below all year round. We showed that high cold tolerance is possible without acclimation regardless of life stage, which presumably correlates with other survival characteristics, such as the starvation resistance of free-living ectoparasites.
“Agreement Supersedes Law, and Love Judgment:” Legal Flexibility and Amicable Settlement in Anglo-Norman England
Authors: Keyser Richard L.
Published: February 2012

The anonymous author of theLaws of Henry I (Leges Henrici Primi)seems to undercut the value of the laws and courts of early-twelfth-century England by making a number of pessimistic comments about the capacity of formal legal proceedings to render justice. At a few points in this treatise, probably completed shortly after 1108, he also voices a preference for friendly agreement. Noting that similar predilections were widespread in medieval Europe, many recent scholars have seized on one of the author's remarks that explicitly compares these two approaches to conflict resolution by proclaiming:Pactum enim legem uincit et amor iudicium, which is translated by L. J. Downer, the work's most recent editor, as, “For an agreement supersedes law and amicable settlement a court judgment.” Ever since Stephen White and Michael Clanchy used this Latin sentence as, respectively, a title and an opening epigram in influential essays written over 25 years ago, it has become a scholarly commonplace, epitomizing what is now often seen as a deep-seated medieval preference for settling disputes through informal compromise. Most scholars that refer to this aphorism, however, use it merely as an illustrative device, without exploring this provocative assertion's meaning in its original textual setting. When considered in light of theLeges Henrici Primi(henceforth:LHP) as a whole and this work's wider context, this statement proves more revealing of complex contemporary attitudes about agreements, conflict resolution, and law than the frequent reference to what is taken to be a categorical declaration of the superiority of friendly concord might suggest.
Federalists, Federalism, and Federal Jurisdiction
Authors: LaCroix Alison L.
Published: February 2012

Historians and legal scholars generally agree that during John Marshall's tenure as chief justice of the United States Supreme Court from 1801 to 1835, the federal judiciary expanded its power to interpret the Constitution and asserted with increasing force its authority to speak on behalf of the Union. This single story of judicial nationalism, however, contains two distinct and largely non-overlapping strands. Historians have tended to focus on the Supreme Court alone, to the exclusion of the lower federal courts, and have largely treated early national controversies over the lower federal courts as outgrowths of the political turmoil that accompanied the emergence of the first party system. Legal scholars in the fields of federal courts and constitutional law, meanwhile, have devoted significant attention to the lower federal courts but have largely neglected the history of how those courts developed beyond the key early moments of the Constitutional Convention and the First Congress.
Plaintiffs v. Privateers: Litigation and Foreign Affairs in the Federal Courts, 1816–1822
Authors: Arlyck Kevin
Published: February 2012

On January 24, 1817, Don Juan Stoughton, the Spanish consul in Boston, wrote to his colleague in Baltimore, Don Pablo Chacon, to thank him for his recent efforts in supplying Stoughton with information about theMangore, a private armed vessel recently arrived in the Chesapeake. Stoughton believed that the privateer was responsible for the capture of a Spanish-owned merchant ship that had recently turned up in Massachusetts. Stoughton had recently filed suit in federal district court to recover the vessel and its cargo on behalf of the rightful owners, but to do so he had to establish that, in the course of its recent expedition, theMangorehad violated federal law prescribing American neutrality. In addition to providing intelligence in this matter, Chacon had secured local counsel to represent Stoughton at depositions of privateer crew members being taken in Baltimore.
MEDIUM RUN REDUX
Authors: McAdam Peter , Willman Alpo
Published: February 2012

We develop a framework for measuring and analyzing medium-run departures from balanced growth, and apply it to developments in the euro area. A time-varying factor-augmenting production function (mimicking directed technical change) with below-unitary substitution elasticity is shown to account for the observed dynamics of factor incomes shares, TFP growth, and its components. Based on careful data accounting, we also identify a rising markup and the importance of financial-market regulations in the 1970s. The balanced growth path emerges as a special (and testable) case of our framework, as do existing strands of medium-run debates.
An epidemiological survey of children's iodine nutrition and goitre status in regions with mildly excessive iodine in drinking water in Hebei Province, China
Authors: Lv Shengmin , Zhao Jun , Xu Dong , Chong Zhengshui , Jia Lihui , Du Yonggui , Ma Jing , Rutherford Shannon
Published: February 2012

Objective

To identify children's iodine nutrition and goitre status in areas with mildly excessive iodine in drinking water.

Design

A cross-sectional survey. Probability proportional to size sampling was employed to randomly select children from thirty townships where the median iodine content in drinking water ranged from 150 to 300 μg/l; their urinary iodine concentrations were determined and their thyroid volumes were measured by ultrasound. Drinking water samples and salt samples from the villages where the children lived were collected using a systematic sampling method.

Setting

Hebei Province of China.

Subjects

A total of 1259 children aged 8–10 years (621 boys and 638 girls).

Results

Children's median urinary iodine concentration was found to be 418·8 μg/l, and the iodine concentration was >300 μg/l for 68·3 % (248/363) of the urine samples. Children's median urinary iodine concentration in villages with median salt iodine >10 mg/kg was significantly higher than that in villages with median salt iodine <5 mg/kg (442·9 μg/l v. 305·4 μg/l, P ≈ 0). The goitre rate of 1259 children examined by ultrasound was 10·96 %.

Conclusions

The iodine intake of children living in areas with mildly excessive iodine in drinking water in Hebei Province was found to be excessive. The measured iodine excess in the sampled children is exacerbated by consumption of iodized salt. Goitre was identified in these areas; however, due to the limitation of the current criteria for children's thyroid volume, a comprehensive assessment of the prevalence of goitre in these regions could not be made and further study is required.
How Fast is Fear?
Authors: Åsli Ole , Flaten Magne Arve
Published: February 2012

The minimum latency of potentiated startle after delay and trace fear conditioning was investigated. Delay conditioning is hypothesized to be mediated by automatic processes, whereas trace conditioning is hypothesized to involve controlled cognitive processes. In a group receiving delay conditioning, a tone conditioned stimulus (CS) signaled an electric shock unconditioned stimulus (US) presented 1,000 ms after CS onset. In a group receiving trace conditioning, a 200 ms tone CS was followed by an 800 ms gap prior to US presentation. Two control groups received unpaired CS/US presentations. It was hypothesized that fear-potentiated startle should be observed at shorter time intervals after CS onset in the group receiving delay conditioning compared to the group receiving trace conditioning. The results showed increased startle at 100 and 150 ms after CS onset in the group receiving delay conditioning compared to the unpaired group. In the group receiving trace conditioning, increased startle was observed at 1,500 ms after CS onset compared to the unpaired group. This supports the idea that conditioned fear after delay conditioning may be due to automatic processes, whereas trace conditioning is dependent on controlled processes.
Heart Rate Variability Modulates Eye-Blink Startle in Women With Bulimic Symptoms
Authors: Rodríguez-Ruiz Sonia , Guerra Pedro M. , Moreno Silvia , Fernández M. Carmen , Vila Jaime
Published: February 2012

The aim of the present study was to examine the modulatory influence of heart rate variability (HRV), an index of autonomic regulation, on eye-blink startle in women with bulimic symptoms. Twenty-four women with bulimic symptoms and 24 control women underwent a psychophysiological test to assess their HRVs during a rest period. They then underwent 20 trials designed to measure their startle motor reflexes while viewing pictures of food and pleasant, neutral, and unpleasant pictures. Women with bulimic symptoms and low HRV had larger startle magnitudes while viewing the pictures than women with both bulimic symptoms and high HRV and control women. A negative relationship between HRV and startle magnitude while viewing food pictures was also found in this group. These findings suggest that poor autonomic regulation, indicated by low HRV, plays a modulatory influence in women with bulimic symptoms.
Disengaging From a Task
Authors: Barber Larissa K. , Grawitch Matthew J. , Munz David C.
Published: February 2012

This study tests the assumption that disengagement from a task indicates poor self-control, especially following little progress. A total of 120 undergraduate students worked on Sudoku puzzles, a logical reasoning task for which progress could be measured. A binary logistic regression revealed a three-way interaction among dispositional self-control, dispositional self-awareness, and actual task progress in predicting disengagement versus persistence. Among individuals with high self-awareness, greater self-control was associated with significantly higher probabilities of task persistence during high task progress. Alternatively, greater self-control was associated with lower probabilities of task persistence during low task progress among individuals with high self-awareness. These results support theories of adaptive goal disengagement suggesting that how individuals apply control is dependent on factors other than self-regulatory capacity. Specifically, assessments of progress among highly self-aware individuals may facilitate adaptive self-regulation.
An analysis of thermospheric density response to solar flares during 2001–2006
Authors: Le Huijun , Liu Libo , Wan Weixing
Published: February 2012

Previous studies show there are significant thermospheric responses to the two great solar flares on October 28, 2003 (X17.2) and November 4, 2003 (X28). In the present study, we further explored the thermospheric response to all X‐class solar flares during 2001–2006. The observed results show that X5 and stronger solar flares can induce an average enhancement of 10–13% in thermospheric density in latitude 50°S‐50°N within ∼4 h after the flare onset. Many important lines and continua in solar EUV region are optically thick, thus EUV enhancements are smaller for flares located near the solar limb due to absorption by the solar atmosphere. Limb flares induce smaller thermospheric responses, due to the limb effect of solar EUV. The thermospheric density enhancement is much more correlated with integrated EUV flux than with peak EUV flux, with a high correlation coefficient of 0.91, which suggests that thermospheric response is strongly dependent on the total integrated energy into the thermosphere.
Two Wide‐Angle Imaging Neutral‐Atom Spectrometers and Interstellar Boundary Explorer energetic neutral atom imaging of the 5 April 2010 substorm
Authors: McComas D. J. , Buzulukova N. , Connors M. G. , Dayeh M. A. , Goldstein J. , Funsten H. O. , Fuselier S. , Schwadron N. A. , Valek P.
Published: February 2012

This study is the first to combine energetic neutral atom (ENA) observations from Two Wide‐Angle Imaging Neutral‐Atom Spectrometers (TWINS) and Interstellar Boundary Explorer (IBEX). Here we examine the arrival of an interplanetary shock and the subsequent geomagnetically effective substorm on 5 April 2010, which was associated with the Galaxy 15 communications satellite anomaly. IBEX shows sharply enhanced ENA emissions immediately upon compression of the dayside magnetosphere at 08:26:17+/−9 s UT. The compression drove a markedly different spectral shape for the dayside emissions, with a strong enhancement at energies >1 keV, which persisted for hours after the shock arrival, consistent with the higher solar wind speed, density, and dynamic pressure (∼10 nPa) after the shock. TWINS ENA observations indicate a slower response of the ring current and precipitation of ring current ions as low‐altitude emissions ∼15 min later, with the >50 keV ion precipitation leading the <10 keV precipitation by ∼20 min. These observations suggest internal magnetospheric processes are occurring after compression of the magnetosphere and before the ring current ions end up in the loss cone and precipitate into the ionosphere. We also compare MHD simulation results with both the TWINS and IBEX ENA observations; while the overall fluxes and distributions of emissions were generally similar, there were significant quantitative differences. Such differences emphasize the complexity of the magnetospheric system and importance of the global perspective for macroscopic magnetospheric studies. Finally, Appendix A documents important details of the TWINS data processing, including improved binning procedures, smoothing of images to a given level of statistical accuracy, and differential background subtraction.
In‐flight degradation correction of SCIAMACHY UV reflectances and Absorbing Aerosol Index
Authors: Tilstra L. G. , de Graaf M. , Aben I. , Stammes P.
Published: February 2012

In this paper we study the close relationship between the radiometric calibration of a satellite instrument and the Absorbing Aerosol Index (AAI) derived from the observed Earth reflectance. Instrument degradation of the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) instrument in the ultraviolet wavelength range is examined by analyzing time series of global means of the AAI, making use of the experience that the global mean should be more or less constant when instrument degradation is absent. The analysis reveals the magnitude of the (scan angle dependent) instrument degradation of SCIAMACHY and also shows that currently available correction techniques are not able to correct the instrument degradation in a sufficient manner. We therefore develop and introduce a new method for degradation correction, which is based on the analysis of the time evolution of the global mean reflectance. Seasonal variations in the global mean reflectance, which mainly result from seasonal variations in scattering geometry and global cloud coverage, are separated from the time series in order to isolate the instrument degradation. Finally, we apply the derived reflectance correction factors to the SCIAMACHY reflectances and calculate the AAI to find that the effects of instrument degradation are reduced to within the 0.1 index point level. The derived AAI is also compared with the AAI based on other correction techniques. The proposed in‐flight reflectance degradation correction method performs best in all aspects.
Global temperature response to radiative forcing: Solar cycle versus volcanic eruptions
Authors: Rypdal K.
Published: February 2012

I show that the peak‐to‐peak amplitude of the global mean surface temperature response to the 11‐year cyclic total irradiance forcing is an order of magnitude less than the amplitude of a cyclic component roughly in phase with the solar forcing which has been observed in the temperature record in the period 1959–2004. If this cyclic temperature component were a response to the solar forcing, it would imply the existence of strong amplifying feedbacks which operate exclusively for solar forcing, such as top‐down mechanisms responding to the large variability in the ultraviolet part of the solar spectrum. I demonstrate, however, that the apparent cyclic component in the temperature record is dominated by the response to five major volcanic eruptions some of which incidentally took place a few years before solar minimum in four consecutive solar cycles, and hence that the correlation with the solar cycle is coincidental. A temperature rise of approximately 0.15 K over the 20th century ascribed to an increasing trend in solar forcing is more than offset by a cooling trend of about 0.3 K due to stratospheric aerosols from volcanic eruptions.
Silicic acid biogeochemistry in the Gulf of California: Insights from sedimentary Si isotopes
Authors: Pichevin Laetitia , Ganeshram Raja S. , Reynolds Ben C. , Prahl Fredrick , Pedersen Thomas F. , Thunell Robert , McClymont Erin L.
Published: February 2012

Iron is considered to play a large role in the cycling of Si in Fe‐limited regions of the ocean, but little is known about its role in Si biogeochemistry outside these areas. Here, we present published sediment trap data, new nutrient profiles and high resolution sedimentary records (Si isotopes, Biogenic silica%, N% and C%) from the Gulf of California, a non‐Fe‐limited region, to investigate the history of Si cycling in this highly productive basin. Modern nutrient profiles show that silicic acid in subsurface waters is in excess relative to nitrate and is therefore incompletely utilized during moderate winter upwelling events. Modern data, however, suggest that during intense upwelling episodes, silicic acid is preferentially utilized relative to nitrate by the biota, which we suggest reflects transient iron limitation. Our new δ30Si record from the Guaymas Basin shows dramatic variations at millennial timescales. Low δ30Si values synchronous with Heinrich events are interpreted as resulting from the decline in Si(OH)4 utilization at times of decreased upwelling strength, while nearly complete Si(OH)4 utilization was observed at times of invigorated upwelling and increased opal burial during the Holocene, the Bølling‐Allerød and the last glacial period. We attribute the complete utilization of Si(OH)4 to the occurrence of transient Fe limitation at these times. Our study highlights the importance of Fe limitation on Si and C cycling in coastal upwelling regions and suggests that upwelling dynamics, in combination with Fe availability, have the potential to modulate marine Si distribution and opal burial even at short timescales.
Novel postcompression technique in the matrix decomposition algorithm for the analysis of electromagnetic problems
Authors: Jiang Zhaoneng , Chen Ru‐shan , Fan Zhenhong , Zhu Maomao
Published: February 2012

In order to efficiently analyze an electromagnetic scattering problem with the surface integral equation approach, the matrix decomposition algorithm (MDA) is used to accelerate the matrix‐vector multiplication when the corresponding matrix equation is solved by a Krylov‐subspace iterative method. Although the MDA is more efficient than the direct solution, this paper presents a novel recompression technique to further reduce computation time and storage memory. The technique applies singular value decomposition (SVD) to the matrices of MDA. Using the novel recompression technique, a sparser representation of the impedance matrix is obtained, and a more efficient matrix‐vector multiplication is implemented. The modified MDA is comparable with the multilevel matrix decomposition algorithm (MLMDA) and the matrix decomposition algorithm‐singular value decomposition (MDA‐SVD) in terms of computation time and memory requirement. Remarkably, the new formulation can reduce the computational time and memory significantly, with excellent accuracy.
Junctional Protein Regulation by Sphingosine Kinase 2 Contributes to Blood–Brain Barrier Protection in Hypoxic Preconditioning-Induced Cerebral Ischemic Tolerance
Authors: Wacker Bradley K , Freie Angela B , Perfater Jennifer L , Gidday Jeffrey M
Published: February 2012

Protection of the blood–brain barrier (BBB) is correlated with improved outcome in stroke. Sphingosine kinase (SphK)-directed production of sphingosine-1-phosphate, which we previously documented as being vital to preconditioning-induced stroke protection, mediates peripheral vascular integrity via junctional protein regulation. We used a hypoxic preconditioning (HPC) model in adult wild-type and SphK2-null mice to examine the isoform-specific role of SphK2 signaling for ischemic tolerance to transient middle cerebral artery occlusion and attendant BBB protection. Reductions in infarct volume and BBB permeability in HPC-treated mice were completely lost in SphK2-null mice. Hypoxic preconditioning-induced attenuation of postischemic BBB disruption in wild types, evidenced by reduced extravascular immunoglobulin G intensity, suggests direct protection of BBB integrity. Measurement of BBB junctional protein status in response to HPC revealed SphK2-dependent increases in triton-insoluble claudin-5 and VE-cadherin, which may serve to strengthen the BBB before stroke. Postischemic loss of VE-cadherin, occludin, and zona occludens-1 in SphK2-null mice with prior HPC suggests that SphK2-dependent protection of these adherens and tight junction proteins is compulsory for HPC to establish a vasculoprotective phenotype. Further elucidation of the mediators of this endogenous, HPC-activated lipid signaling pathway, and their role in protecting the ischemic BBB, may provide new therapeutic targets for cerebrovascular protection in stroke patients.
Associations of Physical Activity and Sitting Time With the Metabolic Syndrome Among Omani Adults
Authors: Mabry Ruth M. , Winkler Elisabeth A.H. , Reeves Marina M. , Eakin Elizabeth G. , Owen Neville
Published: February 2012

Most findings on associations of physical activity and sedentary behavior with the metabolic syndrome are from developed countries; thus, we examined these relationships in adults from Sur, Oman. The Sur Healthy Lifestyle Survey (n = 1,335) used the World Health Organization (WHO) Stepwise methodology to assess chronic disease risk factors. Odds ratios for the metabolic syndrome were estimated using logistic regression models for domains of physical activity (work, transport, and leisure) and sitting time, and adjusted for confounding variables. Compared to their counterparts doing the least physical activity, lower odds of the metabolic syndrome were observed among those with higher work activity (0.60; 95% confidence interval (CI): 0.45, 0.80) and transport activity (0.69; 95% CI: 0.47, 1.00), but not leisure activity (0.91; 95% CI: 0.64, 1.32). Odds of the metabolic syndrome were higher in those who sat for ≥6 h daily compared to <3 h daily (odds ratio = 1.60, 95% CI: 1.04, 2.44), but not after further adjustment for physical activity. This is the first evidence from the Arabian Gulf on associations of physical activity and sitting time with the metabolic syndrome and provides empirical evidence to inform national physical activity guidelines, policies and programs.
BMI Trajectories Among the Severely Obese: Results From an Electronic Medical Record Population
Authors: Wong Edwin S. , Wang Bruce C.M. , Alfonso‐Cristancho Rafael , Flum David R. , Sullivan Sean D. , Garrison Louis P. , Arterburn David E.
Published: February 2012

Epidemiological studies have documented the growing prevalence of severe obesity during the past three decades. The primary goal of this study was to estimate the trajectory of BMI change over 5+ years in a cohort of subjects identified as severely obese (BMI ≥35). We conducted a retrospective cohort study among adults enrolled in Group Health (GH) in Washington State. We tracked 11,735 subjects with at least one BMI measure of 35 or greater in the calendar year 2005 through April 2010. Population averaged BMI trajectories were estimated as a quadratic function of time using a marginal regression model, adjusting for gender and baseline BMI and age. For the average male in GH, the estimated BMI trajectory exhibited a slightly inverted U‐shaped pattern and a 0.17 increase in BMI over the sample period. For the average female, the BMI trajectory was slightly U‐shaped with BMI decreasing 0.03 units over the sample period. We found a high degree of heterogeneity in the shape of estimated trajectories across baseline characteristics with larger 5‐year BMI increases among younger subjects with a lower initial BMI. We conclude that BMI changes over 5 years among individuals classified as severely obese are generally small and consistent with studies documenting BMI changes for individuals in other lower BMI categories. Our results also suggest that once the 35 BMI threshold is reached, individuals will continue to remain severely obese, especially at younger ages.
Ophthalmologic Findings in Patients with Non-Surgically Treated Blowout Fractures
Authors: Pansell Tony , Alinasab Babak , Westermark Anders , Beckman Mats , Abdi Saber
Published: February 2012

We evaluated the ocular and visual status in a group of patients with a non-surgically treated blowout fracture. Clinical examination with refraction, test of binocular function, and tear film evaluation was performed in 23 patients. These values were statistically correlated with the orbital volume measurements and ocular finding from the patient records at presentation. About 50% of the study group was symptomatic due to low visual acuity from refractive errors and decompensated phorias as a consequence of the blowout fracture. Several patients displayed changes in tear film production. There was no strong correlation between the measured parameters and orbital volume measurements. Patients with a non-surgically treated blowout fracture often display ocular and visual changes after discharge. A routine visual exam is advocated in all patients after the ocular status has stabilized after a blowout fracture.
Medullary Thyroid Carcinoma Surgical Cytoreduction Induces an Increase in Serum Calcitonin and Carcinoembryonic Antigen Doubling Times
Authors: Papapetrou P. , Polymeris A.
Published: February 2012

Serum calcitonin (Ct) and carcinoembryonic antigen (CEA) doubling times (DT) are considered to be strong prognostic markers in patients with medullary thyroid carcinoma (MTC). The Objective of this work is to study the effect of MTC debulking on Ct and CEA DTs. 4 patients with MTC are presented who after an initial neck operation had residual disease were followed-up with serial measurements of serum Ct and CEA for several years before and after a secondary incomplete removal of involved cervical lymph nodes.

The patients received no other treatment for MTC. Ct and CEA DTs were determined after fitting the Ct or CEA values to an exponential growth equation.

In patient A, Ct DT increased from 1.45 years (1.17–1.89, 95% CI) preoperatively, to 5.72 (3.22–25.77) postoperatively. In patient B, Ct DT was 1.63 years (1.36–2.02) preoperatively, and very long (serum Ct practically ceased increasing) postoperatively. In patient C, Ct DT was 4.03 years (2.22–21.58) before, and very long after the operation. In patient D, Ct DT from 1.16 years (0.82–1.99) before, increased to 4.21 years (3.04–6.86) after the operation. The changes in CEA DTs were similar to those of Ct DTs in 2 patients in whom the tumor was apparently producing the protein.

In conclusion, surgical MTC cytoreduction in 4 patients caused an increase in the Ct and CEA DTs, and the patients could be reclassified in new Ct DT-based strata with better prognosis than before the operation. We hypothesize that such tumor burden reduction may slow the growth of any residual MTC and we discuss mechanisms that could be responsible for this phenomenon.
Multicharged ion source based on Penning-type discharge with electron cyclotron resonance heating by millimeter waves
Authors: Vodopyanov A. V. , Izotov I. V. , Mansfeld D. A. , Yushkov G. Yu.
Published: February 2012

We suggest a Penning-type discharge as a trigger discharge for fast development of pulsed electron cyclotron resonance plasma. The Penning-type discharge glows at a low pressure as needed. Gyrotron radiation (75 GHz, 200 kW, 1 ms) was used for plasma heating. Fully striped helium ions were demonstrated, average charge of ions in the plasma was ≈ 2. Experiment and calculations show that high charge states of heavier gases require lower initial pressure and longer development time. Only moderate charge states are achievable in this pulsed scheme.
Use of the focusing multi-slit ion optical system at RUssian Diagnostic Injector (RUDI)
Authors: Listopad A. , Coenen J. , Davydenko V. , Ivanov A. , Mishagin V. , Savkin V. , Schweer B. , Shulzhenko G. , Uhlemann R.
Published: February 2012

The upgrade of the diagnostic neutral beam injector RUDI in 2010 was performed to increase the beam density at the focal plane in accordance with the requirements of charge-exchange recombination spectroscopy diagnostics. A new focusing ion-optical system (IOS) with slit beamlets and an enlarged aperture was optimized for 50% higher nominal beam current and reduced angular divergence with respect to the previous multi-aperture IOS version. The upgraded injector provides the beam current up to 3 A, the measured beam divergence in the direction along the slits is 0.35°. Additionally, the plasma generator was modified to extend the beam pulse to 8 s.
Development of DRAGON electron cyclotron resonance ion source at Institute of Modern Physics
Authors: Lu W. , Xie D. Z. , Zhang X. Z. , Xiong B. , Ruan L. , Sha S. , Zhang W. H. , Cao Y. , Lin S. H. , Guo J. W. , Fang X. , Guo X. H. , Li X. X. , Ma H. Y. , Yang Y. , Wu Q. , Zhao H. Y. , Ma B. H. , Wang H. , Zhu Y. H. , Feng Y. C. , Li J. Y. , Li J. Q. , Sun L. T. , Zhao H. W.
Published: February 2012

A new room temperature electron cyclotron resonance (ECR) ion source, DRAGON, is under construction at IMP. DRAGON is designed to operate at microwaves of frequencies of 14.5–18 GHz. Its axial solenoid coils are cooled with evaporative medium to provide an axial magnetic mirror field of 2.5 T at the injection and 1.4 T at the extraction, respectively. In comparison to other conventional room temperature ECR ion sources, DRAGON has so far the largest bore plasma chamber of inner diameter of 126 mm with maximum radial fields of 1.4–1.5 T produced by a non-Halbach permanent sextupole magnet.
Large magnetocaloric effect for magnetic refrigeration from 210 to ∼275 K in La0.7Ca0.3Mn1−xCoxO3
Authors: Zhang Y. D. , Phan The-Long , Yu S. C.
Published: February 2012

We have studied the magnetic properties and magnetocaloric effect in La0.7Ca0.3Mn1−xCoxO3 (x = 0–0.05) prepared by conventional solid-state reaction. Magnetic measurements versus temperature revealed that both magnetization and the Curie temperature (TC) decreased gradually with increasing Co content (x); TC values are about 270 and 215 K for x = 0.0 and 0.05, respectively. Based on magnetic-field dependences of magnetization recorded at various temperatures, curves of the magnetic entropy change (ΔSM) for the samples were determined. Under an applied field of 15.0 kOe, the maximum ΔSM (named ΔSmax) achieved around TC for x = 0.0 and 0.05 are about 5.9 and 4.8 J · kg−1 · K−1, respectively. While the linewidth of ΔSM curves (δTFWHM) changes from 12 to 16 K with varying x from 0 to 0.05, the relative cooling power (RCP) is in between 67 and 78 J/kg. Though an increase in Co content widens δTFWHM, the samples still exhibit the first-order phase transition. If combining these samples for magnetic refrigeration, the temperature range can be used lying in between 210 and 275 K, where ΔSmax values are stable at about 3.5 J · kg−1 · K−1. RCP is thus about 228 J/kg, and comparable to that of some magnetocaloric alloys. This makes La0.7Ca0.3Mn1−xCoxO3 compounds suitable to magnetic-refrigeration applications.
Analytical study and corresponding experiments for a new resonant magnetic charger with circular spiral coils
Authors: Wang Junhua , Li Jiangui , Ho S. L. , Fu W. N. , Zhao Zhigang , Yan Weili , Sun Mingui
Published: February 2012

This study proposes a new resonant magnetic charger comprising circular spiral coils that operate with a strong coupling effect between the transmitter and the receiver. The two spiral coils are fitted with additional copper tapes to serve as resonant transmitter and receiver coils. The magnetic flux distributions are calculated using temporal coupled mode theory. Analysis results show that the proposed system can dramatically improve the efficiency and extend the power transfer distance. Experiments have been carried out in order to verify the performance of the system. In particular, the trends of output voltages when either the operating frequencies or the transfer distances are changing are reported. The system efficiency obtained experimentally is also given. Both calculated and measured results are in good agreement.
Noncommutative deformation of spinor zero mode and Atiyah-Drinfeld-Hitchin-Manin construction
Authors: Maeda Yoshiaki , Sako Akifumi
Published: February 2012

A method to construct noncommutative instantons as deformations from commutative instantons was provided by Maeda and Sako [J. Geom. Phys. 58, 1784 (2008)]10.1016/j.geomphys.2008.08.006. Using this noncommutative deformed instanton, we investigate the spinor zero modes of the Dirac operator in a noncommutative instanton background on noncommutative \documentclass[12pt]{minimal}\begin{document}${\mathbb R}^4$\end{document}R4, and we modify the index of the Dirac operator on the noncommutative space slightly and show that the number of the zero mode of the Dirac operator is preserved under the noncommutative deformation. We prove the existence of the Green's function associated with instantons on noncommutative \documentclass[12pt]{minimal}\begin{document}${\mathbb R}^4$\end{document}R4, as a smooth deformation of the commutative case. The feature of the zero modes of the Dirac operator and the Green's function derives noncommutative ADHM (Atiyah-Drinfeld-Hitchin-Manin) equations which coincide with the ones introduced by Nekrasov and Schwarz. We show a one-to-one correspondence between the instantons on noncommutative \documentclass[12pt]{minimal}\begin{document}${\mathbb R}^4$\end{document}R4 and ADHM data. An example of a noncommutative instanton and a spinor zero mode are also given.
Investigation of the device instability feature caused by electron trapping in pentacene field effect transistors
Authors: Bum Park Chang
Published: February 2012

The phenomenon of device instability governed by electron trapping was investigated in pentacene field-effect transistors. We found that the threshold voltage shift (ΔVT) increases significantly when the device is exposed to photo-irradiation with the depletion gate bias. This effect reveals that a number of electron trapping sites are located in the pentacene band gap, presenting the mechanism of the photo-induced ΔVT. In addition, we found the specific shift of bias-stressed ΔVT under a monochromatic of 690-500 nm, which reflects that the electron trap states would be distributed between the energy levels of 1.8 and 2.5 eV in the gap state.
The mechanism of the asymmetric SET and RESET speed of graphene oxide based flexible resistive switching memories
Authors: Wang Lu-Hao , Yang Wen , Sun Qing-Qing , Zhou Peng , Lu Hong-Liang , Ding Shi-Jin , Wei Zhang David
Published: February 2012

Oxygen migration is reported as key factors of resistive switching in graphene oxide (GO) based memories by different groups. A flexible nonvolatile resistive switching memory based on GO was fabricated through a spin-coating process. The speed of the SET and RESET operations of the GO memories was found to be significant asymmetric. The RESET speed is in the order of 100 ns under a −5 V voltage while the SET speed is three orders of magnitude slower (100 μs) under a 5 V bias. The behavior of resistive switching speed difference is elucidated by voltage modulated oxygen diffusion barrier change.
New determination of the adiabatic ionization potential of the BaOH radical from laser photoionization-molecular beam experiments and ab initio calculations
Authors: Rossa Maximiliano , Cabanillas-Vidosa Iván , Pino Gustavo A. , Ferrero Juan C.
Published: February 2012

The adiabatic ionization potential of the BaOH radical, as generated in a laser vaporization-supersonic expansion source has been determined by laser photoionization experiments to be (4.55 ± 0.03) eV. This value supports the three lowest out of seven previous experimental estimates, the former ranging from 4.35 to 4.62 eV. The present result is compared to ab initio calculations, as performed using both quantum chemistry at different levels of theory and density functional theory, and trying several effective core potentials and their accompanying basis sets for Ba. The most satisfactory agreement is obtained for either the adiabatic or vertical ionization potentials that derive from post-Hartree-Fock [MP2 and CCSD(T)] treatments of electron correlation, along with consideration of relativistic effects and extensive basis sets for Ba, in both BaOH and BaOH+. Such conclusions extend to the results of related calculations on the Ba−OH dissociation energies of BaOH and BaOH+, which were performed to help in calibrating the present computational study. Bonding in BaOH/BaOH+, as well as possible sources of discrepancy with previous experimental determinations of the BaOH adiabatic ionization potential are discussed.
Nonplanar electron acoustic shock waves in a plasma with electrons featuring Tsallis distribution
Authors: Sahu Biswajit , Tribeche Mouloud
Published: February 2012

The properties of cylindrical and spherical electron acoustic shock waves (EASWs) in an unmagnetized plasma consisting of cold electrons, immobile ions, and hot electrons featuring Tsallis statistics are investigated by employing the reductive perturbation technique. A Korteweg-de Vries Burgers (KdVB) equation is derived and its numerical solution is obtained. The effects of electron nonextensivity and electron kinematic viscosity on the basic features of EA shock waves are discussed in nonplanar geometry. It is found that nonextensive nonplanar EA shock waves behave quite differently from their planar counterpart. Deviations from a pure planar geometry are significant only for times shorter that the inverse of the cold electron plasma frequency. Given that the hot electron dynamics is the most interesting one, and that in many astrophysical scenarios the cold electrons can be significantly rarefied, this restriction is not too limiting for the applicability of our model.
Periodically focused modes in chains of dielectric spheres
Authors: Darafsheh Arash , Astratov Vasily N.
Published: February 2012

We show that, theoretically, Brewster angle conditions for transverse magnetic polarized rays can be periodically reproduced in chains of spheres with index n = 3 giving rise to lossless periodically focused modes with 2D period, where D is the sphere diameter. Using ray tracing for a spherical emitter with the diameter D we show that chains of spheres work as filters of such modes at 1.72 < n < 1.85. This leads to tapering of the focused beams combined with the reduction of their attenuation along the chain. Experimentally, the “beam tapering” effect was observed in chains of 300 μm sapphire spheres with index ∼1.77 in visible.
Directional waveguide coupling from a wavelength-scale deformed microdisk laser
Authors: Redding Brandon , Ge Li , Solomon Glenn S. , Cao Hui
Published: February 2012

We demonstrate uni-directional evanescent coupling of lasing emission from a wavelength-scale deformed microdisk to a waveguide. This is attributed to the Goos-Hänchen shift and Fresnel filtering effect that result in a spatial separation of the clockwise (CW) and counter-clockwise (CCW) propagating ray orbits. By placing the waveguide tangentially at different locations to the cavity boundary, we may selectively couple the CW (CCW) wave out, leaving the CCW (CW) wave inside the cavity, which also reduces the spatial hole burning effect. The device geometry is optimized with a full-wave simulation tool, and the lasing behavior and directional coupling are confirmed experimentally.