bluuebunny/crossref_metadata_2025 huggingface dataset:
Salinity constrains size inequality and allometry in two contrasting mangrove habitats in the Gulf of Mexico
Authors: Méndez-Alonzo Rodrigo , Hernández-Trejo Humberto , López-Portillo Jorge
Published: February 2012

The competition for resources increases size inequality in trees, particularly under low abiotic stress. Because mangrove communities are subject to site-specific salinity (and therefore abiotic stress) gradients, these habitats should differ in height–diameter allometry and size inequality. The size inequality (by the Gini Coefficient, G) and maximum potential height (Hmax from a height–diameter asymptotic model) were determined within the mangrove forest of a coastal lagoon in Veracruz, Mexico in 20 0.25-ha plots, 10 in interdistributary basins (IBs, lower salinity) having Avicennia germinans, Laguncularia racemosa and Rhizophora mangle and 10 in mudflats (MFs, higher salinity) dominated by A. germinans. Size inequality was significantly higher in IBs (G = 0.59 ± 0.02 vs. 0.39 ± 0.03). Due to their significant intercorrelation G, total basal area and density were synthesized in one PCA axis accounting for 67% of total variance and inversely correlated with salinity (R = −0.65, P = 0.003). The height–diameter scaling model reached a stable asymptote (Hmax range: 16–21 m; coefficient of variation CV: 7.7) in IBs, suggesting that trees can still increase their diameter after achieving maximum height. In MFs, no stable asymptote was reached (Hmax range: 11–26 m; CV: 32.5), suggesting a lower growth rate of diameter in the MF trees when compared with IB trees.
A generalised Milne-Thomson theorem for the case of an elliptical inclusion
Authors: OBNOSOV Yu. V. , FADEEV A. V.
Published: February 2012

An ℝ-linear conjugation problem modelling the process of power fields forming in a heterogeneous infinite planar structure with an elliptical inclusion is considered. Exact analytical solutions are derived in the class of piece-wise meromorphic functions with their principal parts fixed. Cases with internal singularities and with singularities of the given principal parts at the interface are investigated.
Scanning Electron Microscopy and Roughness Study of Dental Composite Degradation
Authors: Soares Luís Eduardo Silva , Cortez Louise Ribeiro , Zarur Raquel de Oliveira , Martin Airton Abrahão
Published: February 2012

Our aim was to test the hypothesis that the use of mouthwashes, consumption of soft drinks, as well as the type of light curing unit (LCU), would change the surface roughness (Ra) and morphology of a nanofilled composite resin (Z350® 3M ESPE). Samples (80) were divided into eight groups: Halogen LCU, group 1, saliva (control); group 2, Pepsi Twist®; group 3, Listerine®; group 4, Colgate Plax®; LED LCU, group 5, saliva; group 6, Pepsi Twist®; group 7, Listerine®; group 8, Colgate Plax®. Ra values were measured at baseline, and after 7 and 14 days. One specimen of each group was prepared for scanning electron microscopy analysis after 14 days. The data were subjected to multifactor analysis of variance at a 95% confidence followed by Tukey's honestly significant difference post-hoc test. All the treatments resulted in morphological changes in composite resin surface, and the most significant change was in Pepsi Twist® groups. The samples of G6 had the greatest increase in Ra. The immersion of nanofilled resin in mouthwashes with alcohol and soft drink increases the surface roughness. Polymerization by halogen LCU (reduced light intensity) associated with alcohol contained mouthwash resulted in significant roughness on the composite.
Oral candidiasis: Species identification and their antifungal susceptibility pattern in cancer patients receiving radiation therapy
Authors: Mane Pratibha M. , Pratyusha Y. Hyma
Published: February 2012

Introduction:Radiotherapy-induced hyposalivation encourages oralCandidacolonization that often leads to oral/pharyngeal candidiasis. The objective of this study was to identify theCandidaspecies in lesions of oropharyngeal candidiasis in patients undergoing radiotherapy for head and neck cancers and to find out antifungal susceptibility pattern.

Material and methods:Swabs were collected from 60 patients who developed lesions suggestive of oral candidiasis at the end of 1st week of radiation therapy. Antifungal susceptibility of each of the isolated species was done using disc diffusion method following CLSI guidelines.

Results: Candidawas isolated in 13 cases.C.albicans(7) was the most predominant species; a small number of other species have also been identified. Few strains (3) ofCandidashowed variable resistance to the commonly used antifungal drugs.

Discussion:The colonization ofCandidamay lead to development of infections with drug-resistant strains, and hence the patients receiving radiation for head and neck cancers should undergo microbiological study for oral candidiasis.
Dignity therapy: A feasibility study of elders in long-term care
Authors: Chochinov Harvey Max , Cann Beverley , Cullihall Katherine , Kristjanson Linda , Harlos Mike , McClement Susan E. , Hack Thomas F , Hassard Tom
Published: February 2012

Objective:

The purpose of this study was to assess the feasibility of dignity therapy for the frail elderly.

Method:

Participants were recruited from personal care units contained within a large rehabilitation and long-term care facility in Winnipeg, Manitoba. Two groups of participants were identified; residents who were cognitively able to directly take part in dignity therapy, and residents who, because of cognitive impairment, required that family member(s) take part in dignity therapy on their behalf. Qualitative and quantitative methods were applied in determining responses to dignity therapy from direct participants, proxy participants, and healthcare providers (HCPs).

Results:

Twelve cognitively intact residents completed dignity therapy; 11 cognitively impaired residents were represented in the study by way of family member proxies. The majority of cognitively intact residents found dignity therapy to be helpful; the majority of proxy participants indicated that dignity therapy would be helpful to them and their families. In both groups, HCPs reported the benefits of dignity therapy in terms of changing the way they perceived the resident, teaching them things about the resident they did not previously know; the vast majority indicated that they would recommend it for other residents and their families.

Significance of results:

This study introduces evidence that dignity therapy has a role to play among the frail elderly. It also suggests that whether residents take part directly or by way of family proxies, the acquired benefits—and the effects on healthcare staff—make this area one meriting further study.
Delirium masquerading as depression
Authors: Marchington Katie L. , Carrier Louise , Lawlor Peter G.
Published: February 2012

Objective:

Despite the high prevalence of delirium in palliative care settings, this diagnosis is frequently missed, particularly in patients with hypoactive delirium. These patients are also commonly misdiagnosed with depression because of the overlap in symptoms between the two diagnoses. Failure to promptly diagnose delirium can have significant ramifications in terms of delirium reversal, subsequent patient involvement in end-of-life decision making, and the recognition and treatment of other symptoms.

Method:

We report a case of a 63-year-old French-speaking woman admitted to our inpatient palliative care unit with colorectal cancer and a history of depression. This case report highlights the major challenges associated with making the diagnosis of delirium in a patient with a complex medical history, including depression.

Results:

The patient presented with symptoms of depressed mood and fluctuation in psychomotor activity, but failed to respond to an increase in her fluoxetine treatment in addition to methylphenidate and treatment of her hypothyroidism. A psychiatric assessment in her own language detected features of inattention and confirmed a diagnosis of delirium that was multifactorial, secondary to a combination of posterior reversible encephalopathy syndrome (PRES), hypothyroidism, hepatic dysfunction, and medication.

Significance of Results:

Subsyndromal delirium may present with mood lability, and as delirium and depression can coexist, clinicians should perform a delirium screen for all patients presenting with symptoms of depression, preferably in the patient's first language. Cognitive testing can be particularly helpful in distinguishing delirium, especially hypoactive delirium, from depression.
Assimilation of pCO2 data into a global coupled physical‐biogeochemical ocean model
Authors: While J. , Totterdell I. , Martin M.
Published: February 2012

As part of the CARBOOCEAN project, measurements of the partial pressure of carbon dioxide (pCO2) in the ocean have been collected since 2001. Our aim was to use these data in a data assimilation context to improve the representation of pCO2 and its associated prognostic variables in biogeochemical models. Based upon a sequential framework a new method for the assimilation of pCO2 data was developed. This method had to account for oceanic pCO2 being a derived quantity with a functional dependence on temperature, salinity, dissolved inorganic carbon (DIC), and alkalinity. Our method calculates pCO2 increments using an analysis correction technique and then converts these into increments in model variables. Temperature and salinity are assumed to be error free, and so only DIC and alkalinity are updated. Furthermore, in DIC and alkalinity space increments are taken to be perpendicular to the local line of constant pCO2. Our method was tested by assimilating pCO2 data from 2006 into the NEMO‐HadOCC biogeochemical model and then comparing the output from this model to a control with no pCO2 assimilation. While lack of data prevented the assimilation system from correcting a significant systematic error in the subpolar North Atlantic, results from this experiment showed that pCO2 assimilation, despite limited data, reduced RMS and mean errors and also brought the model closer to climatology in the subtropical North Atlantic.
Extreme changes in the equatorial electrojet under the influence of interplanetary electric field and the associated modification in the low‐latitude F region plasma distribution
Authors: Thampi Smitha V. , Chakrabarty D. , Pathan B. M. , Prabhakaran Nayar S. R. , Kumar Pant Tarun
Published: February 2012

A case of the drastic effects of an eastward prompt penetration and a westward overshielding electric field successively affecting the daytime equatorial ionosphere during the space weather event that occurred on 24 November 2001 is presented. Under the influence of the strong eastward prompt penetration electric field starting from 11:25 Indian standard time (IST), the equatorial electrojet (EEJ) strength reached the maximum value of 225 nT at 12:42 IST, almost 7 times greater than the monthly quiet time mean at the same time. This peak EEJ value exceeds the maximum observed values during the month of November for the entire solar cycle by more than 100 nT, irrespective of quiet or disturbed conditions. Further, owing to an ensuing overshielding event that occurred during the main phase of the storm rather than the end of the main phase, this unusually large EEJ showed an equally strong polarity reversal along with a weakening of the sporadic E layer over the equator. The EEJ strength was reduced from +225 to −120 nT at ∼13:45 IST, resulting in a strong counter electrojet condition. The latitudinal variation of the F region electron density data from the CHAMP satellite reveal an ill‐developed equatorial ionization anomaly at 17:00 IST (11:24 UT) over the Indian sector due to this significant weakening of the zonal electric field. These observations showcase the significant degree to which the low‐latitude ionosphere can be affected by the interplanetary electric field.
Estimating turbidity current conditions from channel morphology: A Froude number approach
Authors: Sequeiros Octavio E.
Published: February 2012

There is a growing need across different disciplines to develop better predictive tools for flow conditions of density and turbidity currents. Apart from resorting to complex numerical modeling or expensive field measurements, little is known about how to estimate gravity flow parameters from scarce available data and how they relate to each other. This study presents a new method to estimate normal flow conditions of gravity flows from channel morphology based on an extensive data set of laboratory and field measurements. The compilation consists of 78 published works containing 1092 combined measurements of velocity and concentration of gravity flows dating as far back as the early 1950s. Because the available data do not span all ranges of the critical parameters, such as bottom slope, a validated Reynolds‐averaged Navier‐Stokes (RANS)κ‐εnumerical model is used to cover the gaps. It is shown that gravity flows fall within a range of Froude numbers spanning 1 order of magnitude centered on unity, as opposed to rivers and open‐channel flows which extend to a much wider range. It is also observed that the transition from subcritical to supercritical flow regime occurs around a slope of 1%, with a spread caused by parameters other than the bed slope, like friction and suspended sediment settling velocity. The method is based on a set of equations relating Froude number to bed slope, combined friction, suspended material, and other flow parameters. The applications range from quick estimations of gravity flow conditions to improved numerical modeling and back calculation of missing parameters. A real case scenario of turbidity current estimation from a submarine canyon off the Nigerian coast is provided as an example.
Global variations of HDO and HDO/H2O ratios in the upper troposphere and lower stratosphere derived from ACE‐FTS satellite measurements
Authors: Randel William J. , Moyer Elisabeth , Park Mijeong , Jensen Eric , Bernath Peter , Walker Kaley , Boone Chris
Published: February 2012

High‐quality satellite observations of water and deuterated water in the upper troposphere and lower stratosphere (UTLS) from the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE‐FTS) are used to map global climatological behavior. Spatial and temporal variability in these data suggest that convection plays a significant role in setting water vapor isotopic composition in these regions. In many instances, enhancements in HDO/H2O (i.e., δD) are closely tied to patterns of climatological deep convection and uncorrelated with water vapor, although convection appears to have different isotopic effects in different locations. The ACE‐FTS data reveal seasonal variations in the tropics and allow mapping of climatological regional structure. These data reveal strong regional isotopic enhancement associated with the North American summer monsoon but not the Asian monsoon or the western Pacific warm pool. We suggest that the isotopic effects of deep convection near the tropopause are moderated by the ambient relative humidity, which controls the amount of convective ice that evaporates. Local convective signals can in turn affect global behavior: the North America monsoon influence introduces a Northern Hemisphere–Southern Hemisphere asymmetry in water isotopic composition in the lower stratosphere that extends into the tropics and influences the apparent seasonal cycle in averaged tropical UTLS data. Seasonal variation in tropical lower stratospheric water isotopic composition extends up to ∼20 km in ACE retrievals, but in contrast to previous reports, there is no clear evidence of propagation beyond the lowermost stratosphere. The reliability of these observations is supported by the broad consistency of ACE‐FTS averaged tropical profiles with previous remote and in situ δD measurements.
A classification scheme for turbulence based on the velocity‐intermittency structure with an application to near‐wall flow and with implications for bed load transport
Authors: Keylock C. J. , Nishimura K. , Peinke J.
Published: February 2012

Kolmogorov's classic theory for turbulence assumed an independence between velocity increments and the value for the velocity itself. However, recent work has called this assumption in to question, which has implications for the structure of atmospheric, oceanic and fluvial flows. Here we propose a conceptually simple analytical framework for studying velocity‐intermittency coupling that is similar in essence to the popular quadrant analysis method for studying near‐wall flows. However, we study the dominant (longitudinal) velocity component along with a measure of the roughness of the signal, given mathematically by its series of Hölder exponents. Thus, we permit a possible dependence between velocity and intermittency. We compare boundary layer data obtained in a wind tunnel to turbulent jets and wake flows. These flow classes all have distinct characteristics, which cause them to be readily distinguished using our technique and the results are robust to changes in flow Reynolds numbers. Classification of environmental flows is then possible based on their similarities to the idealized flow classes and we demonstrate this using laboratory data for flow in a parallel‐channel confluence. Our results have clear implications for sediment transport in a range of geophysical applications as they suggest that the recently proposed impulse‐based methods for studying bed load transport are particularly relevant in domains such as gravel bed river flows where the boundary layer is disrupted and wake interactions predominate.
Ambient seismic noise monitoring of a clay landslide: Toward failure prediction
Authors: Mainsant Guénolé , Larose Eric , Brönnimann Cornelia , Jongmans Denis , Michoud Clément , Jaboyedoff Michel
Published: February 2012

Given that clay‐rich landslides may become mobilized, leading to rapid mass movements (earthflows and debris flows), they pose critical problems in risk management worldwide. The most widely proposed mechanism leading to such flow‐like movements is the increase in water pore pressure in the sliding mass, generating partial or complete liquefaction. This solid‐to‐liquid transition results in a dramatic reduction of mechanical rigidity in the liquefied zones, which could be detected by monitoring shear wave velocity variations. With this purpose in mind, the ambient seismic noise correlation technique has been applied to measure the variation in the seismic surface wave velocity in the Pont Bourquin landslide (Swiss Alps). This small but active composite earthslide‐earthflow was equipped with continuously recording seismic sensors during spring and summer 2010. An earthslide of a few thousand cubic meters was triggered in mid‐August 2010, after a rainy period. This article shows that the seismic velocity of the sliding material, measured from daily noise correlograms, decreased continuously and rapidly for several days prior to the catastrophic event. From a spectral analysis of the velocity decrease, it was possible to determine the location of the change at the base of the sliding layer. These results demonstrate that ambient seismic noise can be used to detect rigidity variations before failure and could potentially be used to predict landslides.
Design of novel piecewise uniform scalar quantizer for Gaussian memoryless source
Authors: Velimirović Lazar , Perić Zoran , Nikolić Jelena
Published: February 2012

In this paper we propose a novel piecewise uniform scalar quantizer model designed for a Gaussian memoryless source. The segment thresholds of this quantizer model are equidistant while the number of reproduction levels inside segments is determined by optimizing the inner distortion and under the constraint of total number of reproduction levels. For the proposed quantizer model the quantization efficiency and signal to quantization noise ratio (SQNR) is studied. On the basis of the comparison with the efficiency and SQNR of uniform quantizer advantages of the proposed quantizer model are shown. Particularly, it is shown that with the proposed quantizer the correlation between the input signal and the quantization error can be eliminated more than by using the uniform quantizer as well as that the proposed quantizer provides higher level of SQNR.
Synthetic diamond opens windows into the deep Earth
Authors: Irifune Tetsuo , Hemley Russell J.
Published: February 2012

As a result of its singular strength and exceptional transparency, diamond plays a unique role in laboratory studies of materials under extreme pressures and temperatures. Historically, the quality and size of the diamond used have been limited to that available from nature. However, researchers can now synthesize various types of diamonds in the laboratory that are harder, tougher, and larger than those available natural diamonds. The physical properties and features of these diamonds allow scientists to study materials at pressure‐temperature conditions ranging from those at Earth's surface to those at the very center of the Earth. In essence, these synthetic diamonds offer new windows into the deep Earth.
Earthquake on a stamp: Emil Wiechert honored
Authors: Barckhausen Udo , Rudloff Alexander
Published: February 2012

To commemorate the 150th birthday of Emil Wiechert, one of the world's first professors of geophysics, the German Federal Ministry of Finance issued a stamp; on it, Wiechert, who was born 26 December 1861, is standing behind one of his famous seismographs and a seismogram of the 1906 San Francisco earthquake recorded at the geophysical institute of the University of Göttingen (Figure 1). Wiechert was born in 1861 in the city of Tilsit, northeastern Prussia (now Sovetsk, Russia). In 1881 he enrolled at the university in the nearby city of Königsberg (now Kaliningrad, Russia), where he studied physics and received his doctoral degree in 1889. From 1890 to 1897 Wiechert worked as an assistant at the Institute of Physics at Königsberg University and during this time made himself a name in theoretical and experimental research.
Measuring the electron density of the magnetosphere
Authors: Balcerak Ernie
Published: February 2012

Researchers have demonstrated the potential use of a new way to measure properties of Earth's magnetosphere, the magnetic bubble that surrounds the planet.Zhai et al. used a property known as Faraday rotation for radio tomographic imaging of the magnetosphere. Faraday rotation occurs when a linearly polarized light wave travels through a magnetized medium such as the magnetosphere. The magnetic field causes the plane of polarization to rotate, and the amount of rotation is directly proportional to the electron density in the medium and to the magnetic field. Because Earth's magnetic field is known, researchers therefore can use measurements of Faraday rotation to reconstruct electron density in the magnetosphere.
Evaluating the global energy balance of Titan
Authors: Balcerak Ernie
Published: February 2012

To understand the weather and climate on Earth as well as on other planets and their moons, scientists need to know the global energy balance, the balance between energy coming in from solar radiation and thermal energy radiated back out of the planet. The energy balance can provide interesting information about a planet. For instance, Jupiter, Saturn, and Neptune emit more energy than they absorb, implying that these planets have an internal heat source. Earth, on the other hand, is in near equilibrium, with energy coming in approximately equaling energy going out, though a small energy imbalance can lead to global climate change.
Interacting ocean waves explain powerful seafloor canyon flows
Authors: Schultz Colin
Published: February 2012

Off the southwestern coast of Taiwan the Gaoping Submarine Canyon meanders in a giant backward S shape as it stretches southwestward toward the South China Sea. In the canyon, a 200‐meter‐deep cut into the seafloor that lies 300 meters below the sea's surface, the waters carry an usually large amount of internal tidal power—9.1 megawatts from the canyon's mouth to its head. Along with the strong flows a region of enhanced vertical mixing sits at the canyon's head. Researchers had previously attributed the anomalous flows to internal waves pushing through the Gaoping Canyon, though the source of the energy remained an open question.
Thermal effects of internal gravity waves in the Martian upper atmosphere
Authors: Medvedev Alexander S. , Yiğit Erdal
Published: February 2012

For the first time, gravity wave‐induced heating and cooling effects were fully and interactively incorporated into a Martian general circulation model (GCM). Simulations with a comprehensive GCM with an implemented spectral nonlinear gravity wave (GW) parameterization revealed significant thermal effects of GWs in the mesosphere and lower thermosphere (MLT) between 100 and 150 km. Wave‐induced heating and cooling rates are comparable with those due to near‐IR CO2 heating and IR CO2cooling, correspondingly. Accounting for thermal effects of GWs results in a colder simulated MLT, with the most of cooling taking place in middle‐ and high‐latitudes. In the winter hemisphere, the temperature decrease can exceed 45 K. The colder simulated MLT is in a good agreement with the SPICAM stellar occultation measurements and Mars Odyssey aerobraking temperature retrievals. Our experiments suggest that thermal effects of GWs are probably a key physical mechanism in the MLT missing in contemporary Martian GCMs.
Hypersaline “wet patches” in Taylor Valley, Antarctica
Authors: Levy Joseph S. , Fountain Andrew G. , Welch Kathy A. , Lyons W. Berry
Published: February 2012

Spatially isolated patches of soil located in Taylor Valley, McMurdo Dry Valleys, Antarctica, are sites of elevated salt content and soil moisture. During Antarctic spring, in the absence of snow melt, visibly wet (reduced albedo) patches of soil are present at the surface. The soil pore fluids are hypersaline and have average water activity of 0.74 (the water activity of a solution determines the equilibrium vapor pressure of that solution), and are an order of magnitude more saline than average soils in the Dry Valleys. These salty soils are 3–5 times more water rich than average soils. Geochemical and meteorological analyses show that these wet patches are sites of direct vapor emplacement into soil pore fluids that may ultimately be sourced by the deliquescence of soil salts. These wet patches represent a non‐precipitation, non‐groundwater source for water into Antarctic permafrost.
Phase coupling in Langmuir wave packets: Evidence of four wave interactions in solar type III radio bursts
Authors: Thejappa G. , MacDowall R. J. , Bergamo M.
Published: February 2012

It is reported that one of the Langmuir wave packets in a type III solar radio burst is observed as a localized field structure with a short duration ∼3.2 ms and high intensity exceeding the strong turbulence thresholds. The peak intensity and short time scale well satisfy the criterion for the observed wave packet to be the collapsing Langmuir envelope soliton. The spectrum of this wave packet contains a resonant peak at the local electron plasma frequency, fpe, a Stokes peak at a frequency slightly lower than fpe, anti‐Stokes peak at a frequency slightly higher thanfpe, and a low frequency enhancement below a few hundred Hz, which satisfy the frequency and wave number resonance conditions of the oscillating two stream instability (OTSI) type of four wave interaction. Here, for the first time, we apply the trispectral analysis technique, and show that the spectral components of this wave packet, namely, the beam‐generated Langmuir wave, Stokes and anti‐Stokes modes are coupled to each other with a high degree of phase coherency (high tricoherence). This conclusively shows that the observed characteristics of the wave packet provide evidence for the OTSI.
Lipoic Acid Improves Mitochondrial Function in Nonalcoholic Steatosis Through the Stimulation of Sirtuin 1 and Sirtuin 3
Authors: Valdecantos M. Pilar , Pérez‐Matute Patricia , González‐Muniesa Pedro , Prieto‐Hontoria Pedro L. , Moreno‐Aliaga Maria J. , Martínez Jose A.
Published: February 2012

Nonalcoholic steatosis is an important hepatic complication of obesity linked to mitochondrial dysfunction and oxidative stress. Lipoic acid (LA) has been reported to have beneficial effects on mitochondrial function and to attenuate oxidative stress. The sirtuin (SIRT) family has been demonstrated to play an important role in the regulation of mitochondrial function and in the activation of antioxidant defenses. In this study, we analyzed the potential protective effect of LA supplementation, via the modulation of mitochondrial defenses through the SIRT pathway, against oxidative stress associated with high‐fat feeding. Wistar rats were fed a standard diet (control group (C), n = 10), a high‐fat diet (obese group (OB), n = 10) and a high‐fat diet supplemented with LA (OLIP, n = 10). A group pair‐fed to the latter group (pair‐fed OLIP group (PFO), n = 6) was also included. LA prevented hepatic triglyceride (TG) accumulation (−68.2%) and liver oxidative damage (P < 0.01) through the inhibition of hydroperoxide (H2O2) production (P < 0.001) and the stimulation of mitochondrial antioxidant defenses. LA treatment upregulated manganese superoxide dismutase (SOD2) (60.6%) and glutathione peroxidase (GPx) (100.2%) activities, and increased the reduced glutathione (GSH): oxidized glutathione (GSSG) ratio and UCP2 mRNA levels (P < 0.001–P < 0.01). Moreover, this molecule reduced oxidative damage in mitochondrial DNA (mtDNA) and increased mitochondrial copy number (P < 0.001– P < 0.01). LA treatment decreased the acetylation levels of Forkhead transcription factor 3a (Foxo3a) and PGC1β (P < 0.001–P < 0.01) through the stimulation of SIRT3 and SIRT1 (P < 0.001). In summary, our results demonstrate that the beneficial effects of LA supplementation on hepatic steatosis could be mediated by its ability to restore the oxidative balance by increasing antioxidant defenses through the deacetylation of Foxo3a and PGC1β by SIRT1 and SIRT3.
Patterns of Weight Change Associated With Long‐Term Weight Change and Cardiovascular Disease Risk Factors in the Look AHEAD Study
Authors: Neiberg Rebecca H. , Wing Rena R. , Bray George A. , Reboussin David M. , Rickman Amy D. , Johnson Karen C. , Kitabchi Abbas E. , Faulconbridge Lucy F. , Kitzman Dalane W. , Espeland Mark A. ,   And the Look AHEAD Research Group
Published: February 2012

This article provides an assessment of the associations that weight‐loss patterns during the first year of an intensive lifestyle intervention have with 4‐year maintenance and health outcomes. Two components described patterns of weight change during the first year of intervention: one reflected the typical pattern of weight loss over the 12 months, but distinguished those who lost larger amounts across the monthly intervals from those who lost less. The second component reflected the weight change trajectory, and distinguished a pattern of initial weight loss followed by regain vs. a more sustained pattern of weight loss. Two thousand four hundred and thirty eight individuals aged 45–76 years with type 2 diabetes mellitus, who enrolled in the weight‐loss intervention of a randomized clinical trial, were assigned scores according to how their weight losses reflected these patterns. Relationships these scores had with weight losses and health outcomes (glycosolated hemoglobin—hemoglobin A1c (HbA1c); systolic blood pressure, high‐density lipoprotein (HDL)‐cholesterol, and triglycerides) over 4 years were described. When compared to those with lower scores on the two components, both individuals who had larger month‐to‐month weight losses in year 1 and whose weight loss was more sustained during the first year had better maintenance of weight loss over 4 years, independent of characteristics traditionally linked to weight loss success (P < 0.001). While relationships with year 4 weight loss were stronger, the pattern of larger monthly weight loss during year 1 was also independently predictive of year 4 levels of HbA1c, HDL‐cholesterol, and systolic blood pressure.
Greater Than Predicted Decrease in Resting Energy Expenditure and Weight Loss: Results From a Systematic Review
Authors: Schwartz Alexander , Kuk Jennifer L. , Lamothe Gilles , Doucet Éric
Published: February 2012

Changes in resting energy expenditure (EE) during weight loss are said to be greater than what can be expected from changes of body mass, i.e., fat mass (FM) and fat‐free mass (FFM) but controversy persists. The primary focus of this study was to investigate whether there is a greater than predicted decrease in resting EE during weight loss in a large sample size through a systematic review. The study data were weighted and a partial residual plot followed by a multiple regression analysis was performed to determine whether FM and FFM can predict the changes of resting EE after weight loss. Another subgroup of studies from which all necessary information was available was analyzed and compared against the Harris—Benedict (HB) prediction equation to determine whether the changes in resting EE were greater than what was expected. Subjects lost 9.4 ± 5.5 kg (P < 0.01) with a mean resting EE decline of 126.4 ± 78.1 kcal/day (P < 0.01). Changes in FM and FFM explained 76.5% and 79.3% of the variance seen in absolute resting EE at baseline and post‐weight loss, respectively (P < 0.01). Analysis of the 1,450 subject subgroup indicated an ∼29.1% greater than predicted decrease in resting EE when compared to the HB prediction equation (P < 0.01). This analysis does not support the notion of a greater than predicted decrease in resting EE after weight loss.
Plant cell walls to ethanol
Authors: Jordan Douglas B. , Bowman Michael J. , Braker Jay D. , Dien Bruce S. , Hector Ronald E. , Lee Charles C. , Mertens Jeffrey A. , Wagschal Kurt
Published: February 2012

Conversion of plant cell walls to ethanol constitutes second generation bioethanol production. The process consists of several steps: biomass selection/genetic modification, physiochemical pretreatment, enzymatic saccharification, fermentation and separation. Ultimately, it is desirable to combine as many of the biochemical steps as possible in a single organism to achieve CBP (consolidated bioprocessing). A commercially ready CBP organism is currently unreported. Production of second generation bioethanol is hindered by economics, particularly in the cost of pretreatment (including waste management and solvent recovery), the cost of saccharification enzymes (particularly exocellulases and endocellulases displaying kcat ~1 s−1 on crystalline cellulose), and the inefficiency of co-fermentation of 5- and 6-carbon monosaccharides (owing in part to redox cofactor imbalances in Saccharomyces cerevisiae).
Cesium dynamics in long pulse operation of negative hydrogen ion sources for fusion
Authors: Fantz U. , Wimmer C.
Published: February 2012

Large scale negative hydrogen ion sources operating stable for 1 h (cw mode) are required for the neutral beam heating system of the fusion experiment ITER. The formation of negative hydrogen ions relies on the surface effect for which cesium is evaporated into the source. In order to monitor the cesium dynamics the laser absorption spectroscopy technique is applied to the long pulse test facility MANITU. In the vacuum phase, without plasma operation the evaporation of cesium and the built-up of the cesium in the source are measured. Typical neutral cesium densities are 1015 m−3. During plasma operation and after the plasma phase a high cesium dynamics is observed, showing also depletion of cesium during long pulses with low cesium amount. The co-extracted electron current decreases with the cesium amount to a certain level whereas the ion current indicates an optimum density range.
Use of a wire scanner for monitoring residual gas ionization in Soreq Applied Research Accelerator Facility 20 keV/u proton/deuteron low energy beam transport beam line
Authors: Vainas B. , Eliyahu I. , Weissman L. , Berkovits D.
Published: February 2012

The ion source end of the Soreq Applied Research Accelerator Facility accelerator consists of a proton/deuteron ECR ion source and a low energy beam transport (LEBT) beam line. An observed reduction of the radio frequency quadrupole transmission with increase of the LEBT current prompted additional study of the LEBT beam properties. Numerous measurements have been made with the LEBT bream profiler wire biased by a variable voltage. Current-voltage characteristics in presence of the proton beam were measured even when the wire was far out of the beam. The current-voltage characteristic in this case strongly resembles an asymmetric diodelike characteristic, which is typical of Langmuir probes monitoring plasma. The measurement of biased wire currents, outside the beam, enables us to estimate the effective charge density in vacuum.
Laser ion source with a double pulse laser system
Authors: Okamura M. , Kondo K. , Gish Allouche G. , Yamamoto T.
Published: February 2012

To extend an ion beam pulse of a laser ion source, multiple laser shots could be used. To check the feasibility of this idea, we tested double laser irradiations on an iron target. When the interval of the two laser shots is longer than 10 μs, the obtained ion current profile was expressed as a sum of two individual expanded laser plasmas. However, if the interval is too close, a current reduction was observed. This technique can be effectively applied to low charge state ion production.
Models of radiofrequency coupling for negative ion sources
Authors: Cavenago M. , Petrenko S.
Published: February 2012

Radiofrequency heating for ICP (inductively coupled plasma) ion sources depends on the source operating pressure, the presence or absence of a Faraday shield, the driver coil geometry, the frequency used, and the magnetic field configuration: in negative ion source a magnetic filter seems necessary for H− survival. The result of single particle simulations showing the possibility of electron acceleration in the preglow regime and for reasonable driver chamber radius (15 cm) is reported, also as a function of the static external magnetic field. An effective plasma conductivity, depending not only from electron density, temperature, and rf field but also on static magnetic field is here presented and compared to previous models. Use of this conductivity and of multiphysics tools for a plasma transport and heating model is shown and discussed for a small source.
Magnetic properties of single crystal EuCo2As2
Authors: Ballinger Jared , Wenger Lowell E. , Vohra Yogesh K. , Sefat Athena S.
Published: February 2012

Magnetization measurements at ambient pressure have been performed on single crystal EuCo2As2, a compound having a similar crystalline structure as the pressure-induced EuFe2As2 superconductor. Similar to the magnetic characteristics of EuFe2As2 at ambient pressure, the effective paramagnetic moment at high temperatures arises primarily from the Eu2+ spins, with the Eu2+ spins ordering antiferromagnetically below 39 K. Also, a strong anisotropic behavior is found below this ordering temperature in both magnetic field and temperature dependences. While the magnetization at the lowest temperatures increases nearly linearly with field for fields parallel to the c-axis, the magnetization for fields parallel to the ab-plane exhibits a step-like behavior before further increasing linearly to the highest applied field of 5.0 T. This behavior can be explained in terms of a spin-reorientation of the Eu2+ spins being in an A-type antiferromagnetic structure. However, unlike for EuFe2As2, no evidence is found for any spin density wave transition at higher temperatures.
The influence of the Rashba field on the current-induced domain wall dynamics: A full micromagnetic analysis, including surface roughness and thermal effects
Authors: Martinez Eduardo
Published: February 2012

A micromagnetic study is carried out to analyze the influence of the spin-orbit Rashba field on the current-driven domain wall dynamics along a ferromagnetic strip with high perpendicular magnetocrystalline anisotropy, taking into account both surface roughness and thermal effects. Similarly to the creep and flow regimes seen in recent experiments, the domain wall velocity increases exponentially and linearly for low and high currents, respectively. The induced transverse Rashba field stabilizes the Bloch structure, extending the rigid mobility regime toward high currents and allowing higher velocities than in single-layer or symmetric stacks with negligible Rashba field.
Field-induced continuous rotation of the polarization in multiferroic Mn0.95Co0.05WO4
Authors: Liang K.-C. , Chaudhury R. P. , Wang Y. Q. , Sun Y. Y. , Lorenz B. , Chu C. W.
Published: February 2012

We report the observation of a continuous rotation of the polarization in Mn0.95Co0.05WO4 under magnetic field. At zero field, this compound shows a transition into the spiral magnetic and ferroelectric phase at 12.2 K, which is the ground state, with the polarization oriented along the b-axis. Increasing b-axis magnetic fields rotate the ferroelectric polarization continuously toward the a-axis, indicating a rotation of the spin spiral plane. This rotation extends over a large field and temperature range. At a constant magnetic field of 3 T, the polarization also rotates from the a-axis at the ferroelectric transition toward the b-axis upon decreasing temperature.
Enhancing cancer therapeutics using size-optimized magnetic fluid hyperthermia
Authors: Khandhar Amit P. , Ferguson R. Matthew , Simon Julian A. , Krishnan Kannan M.
Published: February 2012

Magnetic fluid hyperthermia (MFH) employs heat dissipation from magnetic nanoparticles to elicit a therapeutic outcome in tumor sites, which results in either cell death (>42 °C) or damage (<42 °C) depending on the localized rise in temperature. We investigated the therapeutic effect of MFH in immortalized T lymphocyte (Jurkat) cells using monodisperse magnetite (Fe3O4) nanoparticles (MNPs) synthesized in organic solvents and subsequently transferred to aqueous phase using a biocompatible amphiphilic polymer. Monodisperse MNPs, ∼16 nm diameter, show maximum heating efficiency, or specific loss power (watts/g Fe3O4) in a 373 kHz alternating magnetic field. Our in vitro results, for 15 min of heating, show that only 40% of cells survive for a relatively low dose (490 μg Fe/ml) of these size-optimized MNPs, compared to 80% and 90% survival fraction for 12 and 13 nm MNPs at 600 μg Fe/ml. The significant decrease in cell viability due to MNP-induced hyperthermia from only size-optimized nanoparticles demonstrates the central idea of tailoring size for a specific frequency in order to intrinsically improve the therapeutic potency of MFH by optimizing both dose and time of application.
Evolution of polarization and space charges in semiconducting ferroelectrics
Authors: Suryanarayana Phanish , Bhattacharya Kaushik
Published: February 2012

Ferroelectric perovskites and polymers that are used in a variety of electronic, ultrasonic, and optical applications are often wide-band-gap semiconductors. We present a time-dependent and thermodynamically consistent theory that describes the evolution of polarization and space charges in such materials. We then use it to show that the semiconducting nature of ferroelectrics can have a profound effect on polarization domain switching, hysteresis, and leakage currents. Further, we show how hysteresis and leakage are affected by doping, film thickness, electrode work function, ambient temperature, and loading frequency.
Cryogenic high-frequency readout and control platform for spin qubits
Authors: Colless J. I. , Reilly D. J.
Published: February 2012

We have developed a cryogenic platform for the control and readout of spin qubits that comprises a high density of dc and radio frequency sample interconnects based on a set of coupled printed circuit boards. The modular setup incorporates 24 filtered dc lines, 14 control and readout lines with bandwidth from dc to above 6 GHz, and 2 microwave connections for excitation to 40 GHz. We report the performance of this platform, including signal integrity and crosstalk measurements and discuss design criteria for constructing sample interconnect technology needed for multi-qubit devices.
Lattice cluster theory of associating polymers. II. Enthalpy and entropy of self-assembly and Flory-Huggins interaction parameter χ for solutions of telechelic molecules
Authors: Dudowicz Jacek , Freed Karl F. , Douglas Jack F.
Published: February 2012

The lattice cluster theory for solutions of telechelic polymer chains, developed in paper I, is applied to determine the enthalpy Δhp and entropy Δsp of self-assembly of linear telechelics and to evaluate the Flory-Huggins (FH) interaction parameter χ governing the phase behavior of these systems. Particular focus is placed on examining how these interaction variables depend on the composition of the solution, temperature, van der Waals and local “sticky” interaction energies, and the length of the individual telechelic chains. The FH interaction parameter χ is found to exhibit an entropy-enthalpy compensation effect between the “entropic” and “enthalpic” portions as either the composition or mass of the telechelic species is varied, providing unique theoretical insights into this commonly reported, yet, enigmatic phenomenon.
Lattice cluster theory of associating polymers. I. Solutions of linear telechelic polymer chains
Authors: Dudowicz Jacek , Freed Karl F.
Published: February 2012

The lattice cluster theory (LCT) for the thermodynamics of a wide array of polymer systems has been developed by using an analogy to Mayer's virial expansions for non-ideal gases. However, the high-temperature expansion inherent to the LCT has heretofore precluded its application to systems exhibiting strong, specific “sticky” interactions. The present paper describes a reformulation of the LCT necessary to treat systems with both weak and strong, “sticky” interactions. This initial study concerns solutions of linear telechelic chains (with stickers at the chain ends) as the self-assembling system. The main idea behind this extension of the LCT lies in the extraction of terms associated with the strong interactions from the cluster expansion. The generalized LCT for sticky systems reduces to the quasi-chemical theory of hydrogen bonding of Panyioutou and Sanchez when correlation corrections are neglected in the LCT. A diagrammatic representation is employed to facilitate the evaluation of the corrections to the zeroth-order approximation from short range correlations.
The electron spectro-microscopy beamline at National Synchrotron Light Source II: A wide photon energy range, micro-focusing beamline for photoelectron spectro-microscopies
Authors: Reininger R. , Hulbert S. L. , Johnson P. D. , Sadowski J. T. , Starr D. E. , Chubar O. , Valla T. , Vescovo E.
Published: February 2012

A comprehensive optical design for a high-resolution, high-flux, wide-energy range, micro-focused beamline working in the vacuum ultraviolet and soft x-ray photon energy range is proposed. The beamline is to provide monochromatic radiation to three photoelectron microscopes: a full-field x-ray photoelectron emission microscope and two scanning instruments, one dedicated to angle resolved photoemission spectroscopy (μ-ARPES) and one for ambient pressure x-ray photoelectron spectroscopy and scanning photoelectron microscopy (AP-XPS/SPEM). Microfocusing is achieved with state of the art elliptical cylinders, obtaining a spot size of 1 μm for ARPES and 0.5 μm for AP-XPS/SPEM. A detailed ray tracing analysis quantitatively evaluates the overall beamline performances.