bluuebunny/crossref_metadata_2025 huggingface dataset:
Moral order in a time of damnation: TheHikayat Pataniin historical context
Authors: Bradley Francis R.
Published: April 2009

Previous scholarship on theHikayat Pataniby Andries Teeuw and David Wyatt, and more recently by Davisakd Puaksom, has focused upon the political context of the late seventeenth and early eighteenth centuries that surrounded its authors. In this article, I adopt a different approach by arguing that court intellectuals wrote theHikayat Patanias a way to re-establish a moral order through writing during a era of political and social collapse. Set within the context of region wide economic decline after 1650, the present study of theHikayat Pataniportrays a society in anguish with comparative possibilities across all of Southeast Asia.
Sir David Cuthbertson Medal Lecture Bariatric surgery as a model to study appetite control
Authors: Bueter Marco , le Roux Carel W.
Published: April 2009

The obesity epidemic and its associated morbidity and mortality have led to major research efforts to identify mechanisms that regulate appetite. Gut hormones have recently been found to be an important element in appetite regulation as a result of the signals from the periphery to the brain. Candidate hormones include ghrelin, peptide YY, glucagon-like peptide-1 and gastric inhibitory polypeptide, all of which are currently being investigated as potential obesity treatments. Bariatric surgery is currently the most effective therapy for substantial and sustained weight loss. Understanding how levels of gut hormones are modulated by such procedures has greatly contributed to the comprehension of the underlying mechanisms of appetite and obesity. The present paper is a review of how appetite and levels of gastrointestinal hormones are altered after bariatric surgery. Basic principles of common bariatric procedures and potential mechanisms for appetite regulation by gut hormones are also addressed.
Cognitive functions and glycemic control in children and adolescents with type 1 diabetes
Authors: Ohmann S. , Popow C. , Rami B. , König M. , Blaas S. , Fliri C. , Schober E.
Published: April 2009

Background

The relationship between metabolic control and cognitive function in adolescents with type 1 diabetes (DM type 1) is not clear. We compared the quality of glycemic control (GC) and cognitive measures in adolescents with DM type 1 to find out if the quality of diabetes management is related to cognitive impairment.

Method

We assessed executive functions (EFs) and other neuropsychological and psychosocial variables in 70 adolescent patients with DM type 1 and 20 age-matched controls. Patients were divided into two groups according to their last hemoglobin A1c (HbA1c): acceptable (HbA1c 5.9–8.0%, mean 6.9%, 36 patients, mean age 14 years) and non-optimal (HbA1c 8.2–11.6%, mean 9.3%, 34 patients, mean age 15.6 years).

Results

We found impaired EFs, mainly problems of concept formation (p=0.038), cognitive flexibility (p=0.011) and anticipation (p=0.000), in the patients with DM type 1. Both groups did not differ in intelligence, most assessed EFs and adjustment to chronic illness (Youth Self-Report; YSR). Younger patients (<15 years) were cognitively less flexible. GC was worse in older patients and in patients with longer duration of the disease. We also found significant differences between patients with diabetes and controls concerning somatic complaints, internalizing problems (Child Behavior Checklist; CBCL) and social activity (CBCL and YSR).

Conclusions

DM type 1 is associated with cognitive deficits in adolescents independent of the quality of metabolic control and the duration of the disease. These deficits are probably related to the disease, especially in patients with early-onset diabetes.
Leibniz on ‘prophets’, prophecy, and revelation
Authors: COOK DANIEL J.
Published: April 2009

During Leibniz's lifetime, interest in the interpretation of the Bible and biblical prophecy became central to the theological and political concerns of Protestant Europe. Leibniz's treatment of this phenomenon will be examined in the light of his views on the nature of revelation and its role in his defence of Christianity. It will be argued that Leibniz's defence of the miracle of revelation (and its vehicle, biblical prophecy) – unlike his arguments on behalf of the core Christian mysteries of the Trinity and Incarnation – is demonstrable by purely natural and scientific means, especially the verification of history.
Security and the problem of context: a hermeneutical critique of securitisation theory
Authors: CIUTǍ FELIX
Published: April 2009

How do we know when we are dealing with security issue? This is a cardinal question in Security Studies, and securitisation theory provides and authoritative yet incomplete answer, mainly because it rules out that the meaning of security can vary contextually. To overcome this limitation, we need a hermeneutical perspective centred on the liminality of security as a category in-between theory and policy, which produces a more precise algorithm for empirical research. A contextual hermeneutics of security signals that normative awareness is necessary even in the absence of a unifying normative manifesto, also confronts the spectre of the “death of security” invoked by those who object to the potentially endless broadening of its meaning.
Bi-directional pheromone communication between robots
Authors: Purnamadjaja Anies Hannawati , Russell R. Andrew
Published: April 2009

This paper describes a project that aims to demonstrate two-way communication between robots using chemical signals. The project is part of a wider investigation examining the potential advantages and drawbacks of implementing pheromone signalling between robots. It is well known that all kinds of biological creatures use chemicals as a means of attracting, repelling, controlling, guiding and informing their fellow creatures. This very wide range of effective biological forms of chemical communication is the inspiration to look at potential robotic applications. In previous work involving the use of physical chemical signals in robotics the case of one robot releasing or depositing a chemical for other robots (or the same robot) to detect and act upon has been addressed. This project moves a step forward to investigate a group of robots where each group member emits and detects pheromone chemicals. The example task addressed in the project is to use chemical signalling to help a collection of robots to assess group size. Bacteria provide a model for this kind of chemical communication. By monitoring chemical concentration bacteria can assess group size and hence modify their behaviour as appropriate. Although not intending to model bacterial quorum sensing in detail this behaviour provides inspiration for our demonstration of bi-directional communication. This paper provides details of the implementation of quorum sensing in a group of robots. The robots used in the project, their control algorithms and experimental results are presented. Both beneficial aspects and the pitfalls of pheromone communication in robotic systems are also discussed.
Truncated Fourier series formulation for bipedal walking balance control
Authors: Yang Lin , Chew Chee-Meng , Zheng Yu , Poo Aun-Neow
Published: April 2009

This paper studies the parameters contained in the truncated Fourier series (TFS) formulation for bipedal walking balance control. Using the TFS generated lateral motion reference, 3D bipedal walking can be directly achieved without any parameter adjustment. Furthermore, the potential of this TFS formulation for motion balance control has also been investigated. One more motion balance strategy is developed through the reinforcement learning, which adjusts the motion's reference trajectory according to the selected dynamic feedback in real time. Dynamic simulation results of the presented balance control method show that the resulting motion can be constrained periodical and long-distance 3D bipedal walking motions are achievable.
Parliamentary Report
Authors: Cranmer Frank
Published: April 2009

The Cremation (England and Wales) Regulations 2008, which were put in place in the wake of the Shipman murders and the subsequent inquiry by Dame Janet Smith, came into effect on 1 January 2009. They modernise and consolidate all previous regulations, and replace the Cremation Regulations 1930, as amended. However, the new Regulations are themselves an interim measure, to be replaced in due course by a new system of death certification under the Coroners and Justice Bill, which was introduced into the House of Commons in January 2009.
On a Speculated Relation Between Chvátal–Sankoff Constants of Several Sequences
Authors: KIWI M. , SOTO J.
Published: April 2009

It is well known that, when normalized byn, the expected length of a longest common subsequence ofdsequences of lengthnover an alphabet of size σ converges to a constant γσ,d. We disprove a speculation by Steele regarding a possible relation between γ2,dand γ2,2. In order to do that we also obtain some new lower bounds for γσ,d, when both σ anddare small integers.
Modifications of chemically induced-enucleated nuclear transfer technique by reverse-order nuclear transfer in mouse
Authors: Wang Yongsheng , Liu Jun , Tang Shuang , An Zhixing , Guo Zhilin , Ding Xiangbin , Liu Fengjun , Cao Zelei , Zhang Tuo , Zhang Yong
Published: April 2009

To improve the developmental potential of somatic cell cloned embryos derived from demecolcine (DC) induced-enucleated nuclear transfer (INT), we modified the INT procedures by transferring donor nuclei into recipient cytoplasts prior to the induced enucleation of the recipient cytoplasts, and we called this modified INT technique as reverse-order and induced-enucleated nuclear transfer (RINT). Standard nuclear transfer (SNT) and INT were performed as controls. The dynamic changes of maternal and transferred donor nuclei in the RINT oocytes were monitored to evaluate the feasibility of this new nuclear transfer (NT) technique by timed immunofluorescence. Timed immunofluorescence showed that RINT is feasible because none of the transferred donor nuclei were expelled with the second polar body (Pb) in the RINT oocytes, while 42.2% of the oocytes showed extrusion of all maternal chromosome and spindles with the second Pb at 60 min after activation and DC treatment. Although there was no difference in cleavage rate (86.6% vs. 82.1%), the rates of successful enucleation and blastocyst formation were significantly increased in RINT compared with INT (44.1% vs. 27.5% and 43.3% vs. 12.8%, respectively;p< 0.01). Compared with SNT, there was no difference in cleavage rate (86.6% vs. 78.4%), but the blastocyst developmental rate was significantly increased in the RINT group (43.3% vs. 25.3%;p< 0.01). Blastocysts derived from RINT had a higher total cell number than those from SNT (45.1 ± 3 vs. 37.6 ± 4;p< 0.05). Our results provide evidence that RINT is feasible and may provide a more efficient and simple method for NT than INT.
Apoptotic processes and DNA cytosine methylation in mouse embryos arrested at the 2-cell stage
Authors: Fabian Dušan , Bukovská Alexandra , Juhás Štefan , Koppel Juraj
Published: April 2009

The present study evaluates the role of apoptotic cell death and DNA methylation reprogramming in early developmental failures occurring in embryos at the 2-cell stage. Mouse 2-cell embryos were culturedin vitroand treated with chemicals that cause developmental arrest and apoptosis (α-amanitin, actinomycin D, TNF-α). After 24 h, 48 h and 72 h culture, embryos were analysed using cell-death assays (annexin V staining, TUNEL labelling and immunodetection of active caspase-3) and genome methylation assay (immunodetection of 5-methylcytosine). The ability of embryos at the 2-cell stage to undergo apoptotic processes was very low. In arrested embryos, the presence of all evaluated features of apoptosis was recorded only after 72 h culture and their incidence was sporadical. Interestingly, the most frequently observed apoptotic sign was nuclear condensation and the timing of its appearance preceded even the phosphatidylserine flip. Both normally developing and arrested embryos displayed reduction in DNA cytosine methylation. In arrested embryos, this process was independent of cellular cleavage, was more pronounced and finished in almost complete demethylation of the embryonic genome. The timing of the demethylation overlapped with the onset of major apoptotic events. Although observed apoptotic cells showed either demethylated or methylated DNA cytosine in their nuclei, at blastocyst stage the demethylated status appeared more frequently in them.
Dynamics in Complex Systems
Authors: Kurths J. , Maraun D. , Zhou C. S. , Zamora-Lopez G. , Zou Y.
Published: April 2009

Over the last decade, we have witnessed the birth of a new movement of interest and research in the study of complex networks. These networks often have irregular structural properties, but also encompass rich dynamics. The interplay between the network topological structure and the associated dynamics attracts a lot of interest. In this research line, we propose a network approach to dealing with complex dynamics, in particular with synchronization dynamics. From the methodological perspective, this approach requires novel ideas from nonlinear sciences, statistical physics and mathematical statistics. Furthermore, we show applications in different disciplines, from earth sciences to brain dynamics. The complex network’s approach is an interdisciplinary topic and could be promising for the understanding of complexity from a systems level.
How to Cope with Climate’s Complexity?
Authors: Crucifix Michel
Published: April 2009

Climate exhibits a vast range of dissipative structures. Some have characteristic times of a few days; others evolve over thousands of years. All these structures are interdependent; in other words, they communicate. It is often considered that the only way to cope with climate complexity is to integrate the equations of atmospheric and oceanic motion with the finest possible mesh. Is this the sole strategy? Aren’t we missing another characteristic of the climate system: its ability to destroy and generate information at the macroscopic scale? Paleoclimatologists consider that much of this information is present in palaeoclimate archives. It is therefore natural to build climate models such as to get the most of these archives. The strategy proposed here is based on Bayesian statistics and low-order non-linear dynamical systems, in a modelling approach that explicitly includes the effects of uncertainties. Its practical interest is illustrated through the problem of the timing of the next great glaciation. Is glacial inception overdue or do we need to wait for another 50,000 years before ice caps grow again? Our results indicate a glaciation inception in 50,000 years.
Complexity and Nonlinear Dynamics in Psychotherapy
Authors: Schiepek Günter
Published: April 2009

Human life changes with time. It seems therefore obvious that most of the phenomena that psychology and psychotherapy are concerned with are dynamic in nature. For human development processes, human change and learning processes, the dynamics and prognosis of mental disorders, problems manifesting in social systems such as couples, families, teams, or the question of how psychotherapy works, self-organization is ubiquitous. In the context of self-organization, complexity is a quality of changing patterns and patterns of change, produced by nonlinear coupled systems.
Complex Non-equilibrium Dynamics in Plasmas
Authors: Rost Jan-Michael
Published: April 2009

We will illustrate the universality of strongly coupled plasmas by discussing two new forms of these plasmas, which have only recently become possible to create and observe in the laboratory. They exhibit a wealth of intriguing complex behavior, which can be studied experimentally, in many cases for the first time. Plasmas, gases of charged particles, are universal in the sense that certain properties of complex behavior only depend on ratios of characteristic parameters of the plasma, not on the parameters themselves. Therefore, it is of fundamental and far-reaching consequence, to be able to create and observe a strongly coupled plasma since its behavior is paradigmatic for an entire class of plasmas.
Perceptual Control Theory as an integrative framework and Method of Levels as a cognitive therapy: what are the pros and cons?
Authors: Mansell Warren
Published: April 2009

This article considers the pros and cons of using Method of Levels (MOL), a therapy based on Perceptual Control Theory (PCT). Five concerns about PCT are that it is an early theory, is not well known, originates from outside psychology, implies that established theories are inaccurate and has a mechanistic approach. Five positive features are that it explains how ‘control’ works, takes a phenomenological perspective, is grounded in biology, integrates many disciplines and has an evidence base. Five features of MOL can raise caution: it is not well known, emphasizes intrinsic change, requires the therapist to let go of control, concentrate intensively and use alternative evaluations of outcome. There are major advantages: it is a simple process to learn; theory-practice links are clear, it is ‘ultra cognitive therapy’ – focused on the present moment, client-centred and enables shifting in perspective, promotes service empowerment, and has an evidence base. This article will help therapists make an informed choice about using MOL.
PCT and MOL: a brief history of Perceptual Control Theory and the Method of Levels
Authors: Powers William T.
Published: April 2009

I have been asked to describe how Perceptual Control Theory (PCT) and Method of Levels (MOL) came into being, and as I approach the age of 82 that seems a prudent request. Some parts of the following should probably be taken more as a reconstruction than a verifiable record of the past, but I will strive for realism.
Beurteilung und Notfallmanagement bei akuten Vergiftungen
Authors: von Ow Dieter , Osterwalder Joseph J.
Published: April 2009

Jährlich kommt es in der Schweiz bei Erwachsenen zu rund 250 schweren oder tödlichen Vergiftungen, bei Kindern sind dies ca. 25 (Beratungen des Schweiz. Toxikologischen Informationszentrums). Patienten mit lebensbedrohlichen Symptomen benötigen sofort intensivmedizinische Maßnahmen auf symptomatischer Basis, auch wenn die der Vergiftung zugrunde liegende Noxe noch nicht bekannt ist. Dabei wird das Notfall-ABCDE angewendet (Airway, Breathing, Circulation, Disabilities, Exposure). Die Abklärung der Vergiftungsursache (Identifikation der Noxe) und die weiteren Untersuchungen (EKG, Labor, Röntgen) werden parallel dazu vorangetrieben, und die Ergebnisse werden laufend in der weiteren Therapie berücksichtigt. Bei der Wahl der Behandlungsmodalitäten ist darauf zu achten, dass sie nicht ungünstig mit bekannten oder potentiellen Noxen interagieren und damit die Vergiftung noch verschlimmern. Spezifische Massnahmen können nur ergriffen werden, wenn die Noxen bekannt sind, oder wenn durch die Erkennung eines Toxidroms die Substanzgruppe soweit eingeschränkt werden kann, dass eine gezielte Behandlung möglich ist.
Intoxikationen mit Antidepressiva
Authors: Bodmer Michael
Published: April 2009

Vergiftungen mit Medikamenten gehören mit zu den häufigen Ursachen aufgrund derer Patienten auf einer medizinischen Notfall- oder Intensivstation behandelt werden müssen. Aufgrund ihrer Gefährlichkeit spielen trizyklische Antidepressiva, trotz abnehmender Häufigkeit in den letzten Jahren, auch heute noch eine überragende Rolle. Zu ihrer Toxizität gehören die Beeinträchtigung der myokardialen Erregungsausbreitung- und Rückbildung, zentrale (Sedation, epileptische Anfälle) und periphere anticholinerge Manifestationen sowie die arterielle Hypotonie. Lebensbedrohlich sind Herzrhythmusstörungen wie Kammertachykardien oder Kammerflimmern, Status epilepticus sowie das schwere zentrale anticholinerge Syndrom mit Agitation, Delir und Hyperthermie. Wichtige Therapiemodalitäten sind die Dekontamination mit oraler Aktivkohle innert 1–2 Stunden nach Einnahme, und die antidotale Gabe von Natriumbikarbonat bei Kardiotoxizität. Die selektiven Serotoninwiederaufnahmehemmer (SSRI) und die atypischen Antidepressiva sind weniger toxisch als die trizyklischen Anti­depressiva. Hier ist besonders auf das Auftreten eines Serotoninsyndroms zu achten.
Triggered seismicity associated with the 1990 Nicoya, Costa Rica, Mw = 7.0 earthquake
Authors: Bilek Susan L. , Elliott Candy E. , Bertelloni Carolina Lithgow
Published: April 2009

The 25 March 1990 (Mw = 7.0) subduction megathrust earthquake that occurred offshore the Nicoya Peninsula, Costa Rica, produced a large number of aftershocks on the subduction plate interface as expected and preceded an unusual sequence of earthquakes 75 km inland that had two periods of significant increase, one at 60–90 days and one near 270 days, following the main shock. This inland sequence of events would not typically fall within the classification of aftershocks given their spatial and temporal distance, and we show here that this sequence was likely triggered by the 25 March main shock. We compute stress changes on representative faults within this inland region using both a simple half‐space model as well as with a 2‐D finite element model that incorporates variable rheologic properties. The half‐space model predicts a minor increase in Coulomb stress changes and a large amount of unclamping in this region, likely enough to cause triggering on the inland right‐lateral strike‐slip faults. Models that include a viscoelastic response also indicate stress increases that may link to triggering, particularly related to the time delay. Earthquakes on the subduction zone thrust along Costa Rica should be considered in hazard assessments for the inland populated region as several sets of strike‐slip faults have been mapped in the fore‐arc region.
Neon isotopic measurements using high‐resolution, multicollector noble gas mass spectrometer: HELIX‐MC
Authors: Marrocchi Y. , Burnard P. G. , Hamilton D. , Colin A. , Pujol M. , Zimmermann L. , Marty B.
Published: April 2009

We describe a new high‐resolution, multicollection, noble gas mass spectrometer, the HELIX‐MC, developed by GV instruments. The instrument uses a collector housing that holds five “MiniDual” detection systems, each detector containing two devices: a Faraday cup collector and channel electron multiplier. Each detector is 5.2 mm wide, which permits collecting adjacent beams separated by 1 atomic mass unit (amu) at mass 136. The HELIX‐MC operates at high mass resolution (m/Δm > 1500), which allows the interference of 40Ar++ on 20Ne+ to be resolved. We report the results of some tests on the “MiniDual” collectors, in which we have achieved precise Ne abundance and isotopic measurements. After a correction for doubly ionized CO2 (0.37–1.5%), our results show that the HELIX‐MC produces only very limited instrumental Ne isotopic mass fractionation (≈−0.5%.amu−1). The sensitivity of the HELIX‐MC for neon measurement performed on 1012 ohms collector is around 1.4 × 10−3 A torr−1 for quantities of 20Ne analyzed comprised between 1.27 × 10−15 and 4.71 × 10−15 moles. Within this range, the reproducibility of the isotopic measurements of standard gas falls in the range between 0.5 and 0.8% (1σ) for 20Ne/22Ne and 1 and 1.5% for 21Ne/22Ne over a period of several days. The machine characteristics for measuring He are also reported.
Crustal structure beneath the Florida‐to‐Edmonton broadband seismometer array
Authors: French S. W. , Fischer K. M. , Syracuse E. M. , Wysession M. E.
Published: April 2009

Ps receiver functions were stacked to determine crustal thickness and Vp/Vs ratios for the 28 stations of the Florida‐to‐Edmonton Broadband Seismometer Array and 6 adjacent permanent stations. Roots of thickened crust exist beneath the Paleozoic Appalachian orogen and the Proterozoic Trans‐Hudson orogen. The ratios of surface elevation to root thickness are lower than observed in young, active orogens, as are average crustal root buoyancies determined from gravity data. These results are consistent with global trends, and may be explained by increased crustal root density due to metamorphism. Crustal thickening is also observed beneath the Mid‐Continent Rift in Iowa, consistent with compressional inversion of the rift during the Grenville orogeny.
Influence of stratospheric circulation on the predictability of the tropospheric Northern Annular Mode
Authors: Mukougawa Hitoshi , Hirooka Toshihiko , Kuroda Yuhji
Published: April 2009

Influence of stratospheric circulation on the predictability of the tropospheric Northern Hemisphere Annular Mode (NAM) in the boreal winter is examined using 5‐year archive of 1‐month ensemble forecast dataset provided by the Japan Meteorological Agency (JMA). It is found that the prediction skill of the 7‐day averaged ensemble‐mean NAM index in the upper troposphere is significantly improved for 5‐ to 13‐day forecast when negatively large NAM indices are observed in the stratosphere around 30 hPa at the initial time of forecast in comparison with stratospheric positive NAM events. The regression analysis also supports the significant relationship between large prediction error of the upper tropospheric NAM index and stratospheric westerly anomalies. The asymmetric response of the forecast skill of the upper tropospheric NAM index to the polarity of the stratospheric NAM anomaly is also discussed in terms of the dependence of the upward propagation of planetary waves on stratospheric zonal wind anomalies.
Seismoionospheric GPS total electron content anomalies observed before the 12 May 2008 Mw7.9 Wenchuan earthquake
Authors: Liu J. Y. , Chen Y. I. , Chen C. H. , Liu C. Y. , Chen C. Y. , Nishihashi M. , Li J. Z. , Xia Y. Q. , Oyama K. I. , Hattori K. , Lin C. H.
Published: April 2009

The global ionospheric map (GIM) is used to observe variations in the total electron content (TEC) of the global positioning system (GPS) associated with 35 M ≥ 6.0 earthquakes that occurred in China during the 10‐year period of 1 May 1998 to 30 April 2008. The statistical result indicates that the GPS TEC above the epicenter often pronouncedly decreases on day 3–5 before 17 M ≥ 6.3 earthquakes. The GPS TEC of the GIM and electron density profiles probed by six microsatellites of FORMOSAT3/COSMIC (F3/C) are further employed to simultaneously observe seismoionospheric anomalies during an Mw7.9 earthquake near Wenchuan, China, on 12 May 2008. It is found that GPS TEC above the forthcoming epicenter anomalously decreases in the afternoon period of day 6–4 and in the late evening period of day 3 before the earthquake, but enhances in the afternoon of day 3 before the earthquake. The spatial distributions of the anomalous and extreme reductions and enhancements indicate that the earthquake preparation area is about 1650 km and 2850 km from the epicenter in the latitudinal and longitudinal directions, respectively. The F3/C results further show that the ionospheric F2 peak electron density, NmF2, and height, hmF2, significantly decreases approximately 40% and descends about 50–80 km, respectively, when the GPS TEC anomalously reduces.
Simulations of convectively‐driven density currents in the Atlas region using a regional model: Impacts on dust emission and sensitivity to horizontal resolution and convection schemes
Authors: Reinfried F. , Tegen I. , Heinold B. , Hellmuth O. , Schepanski K. , Cubasch U. , Huebener H. , Knippertz P.
Published: April 2009

During the SAMUM field campaign in southern Morocco in May and June 2006 density currents generated by evaporative cooling after convective precipitation were frequently observed at the Sahara side of the Atlas Mountain chain. The associated strong surface cold‐air outflow during such events has been observed to lead to dust mobilization in the foothills. Here a regional model system is used to simulate a density current case on 3 June 2006 and the subsequent dust emission. The model studies are performed with different parameterization schemes for convection, and with different horizontal model grid resolutions to examine to which extent the model system can be used for reproducing dust emissions in this region. The effect of increasing the horizontal model grid resolution from 14 km to 2.8 km on the strength on the density currents and thus on dust emission is smaller than the differences due to different convection parameterization schemes in this case study. While the results in reproducing the observed density current at the Atlas Mountain varied with different convection parameterizations, the most realistic representation of the density current is obtained at 2.8 km grid resolution at which no parameterization of deep convection is needed.
Region of influence of 13 remote European measurement sites based on modeled carbon monoxide mixing ratios
Authors: Folini D. , Kaufmann P. , Ubl S. , Henne S.
Published: April 2009

The regions of influence (ROIs) of 13 European rural background and high‐altitude measurement sites are quantified based on modeled carbon monoxide (CO) mixing ratios. The mixing ratios have a 3‐hourly time resolution and are obtained by combining regional scale, time‐reversed Lagrangian particle dispersion modeling with gridded CO inventory data. The ROIs of individual sites, defined as the area whose surface emissions account for 80% of modeled mixing ratios, typically cover an area of a few times 105 km2, independent of the altitude of the site. Their geographical shape is influenced by the spatial distribution of surface emissions, by mountain ranges, and by the prevailing westerly winds in Europe. Depending on the site, between 20% and 80% of the variability of the modeled mixing ratios cannot be explained by changing atmospheric transport patterns and must be ascribed to the spatial inhomogeneity of the emission sources instead. The use of time‐dependent CO emissions has an additional 25% effect on modeled mixing ratios. Neither the average modeled mixing ratios nor their variability are indicative of any of these site‐specific properties. As a rule of thumb, the results suggest that sites intended for regional‐scale emission monitoring should not be separated by more than 600 km to achieve good geographical coverage.
Simultaneous observations of the Martian atmosphere by Planetary Fourier Spectrometer on Mars Express and Miniature Thermal Emission Spectrometer on Mars Exploration Rover
Authors: Wolkenberg P. , Grassi D. , Formisano V. , Rinaldi G. , D'Amore M. , Smith M.
Published: April 2009

In this study we present temperature profiles in the lower atmosphere of Mars from simultaneous observations performed by the Planetary Fourier Spectrometer (PFS) aboard the Mars Express spacecraft and the Miniature Thermal Emission Spectrometer (Mini‐TES) aboard the Mars Exploration Rovers. Thermal infrared spectra were collected in both the upward and downward looking geometries from the surface and from orbit, respectively. We used two sets of criteria to select PFS observations. These criteria took into account the location around the landing sites of the rovers, the local time (LT), and the solar longitude (Ls) corresponding to the Martian solar day (sol). The first set of criteria included PFS measurements carried out within ±1° in latitude and longitude, within 1 h in local time, and on the same sol. From the restricted set of measurements we conclude that the PFS data are consistent with the Mini‐TES data. The next set of criteria covered the area 5° × 5° around the landing sites, within 1 h in local time and within 9 sols. The latter criteria allow us to study the variation of parameters LT, distance, and Ls and their influence on changes of temperature profiles. This comparison for the group with relaxed criteria showed also that local time has strongest effect on temperature differences. The main purpose of this study is to confirm the validity of PFS temperature profiles close to the surface. Atmospheric temperatures below 5 km are retrieved from satellite measurements with a large uncertainty because of poor pieces of information in the wings of the CO2 absorption band at 667 cm−1. The Mini‐TES temperature profiles span atmospheric layers below 2 km. The good correspondence observed in a number of cases confirms the possibility of using PFS measurements to investigate the lower atmosphere.
Beam steering dynamics in coupled oscillator based phased arrays with coupling delay
Authors: Pogorzelski Ronald J.
Published: April 2009

A continuum solution for the phase evolution of a coupled oscillator array with coupling delay, when one oscillator is step detuned in time, is derived from the discrete model solution previously published. From this Green's function a differential equation is derived for the Laplace transform of the phase dynamics. The solution of this differential equation is expressed as a sum of the eigenfunctions of the differential operator for a finite length array with one oscillator detuned. The dynamic behavior of the aperture phase for beam steering is obtained by superposing two of the Green's function solutions corresponding to antisymmetric excitation at each end of the array. The far zone beam steering behavior is obtained by summing the elemental radiated signals. Generalization to planar arrays appears to be straightforward. An alternative more flexible formulation suitable for early times is also presented.
Can carbon isotopes be used to predict watershed‐scale transpiration?
Authors: Pypker T. G. , Barnard H. R. , Hauck M. , Sulzman E. W. , Unsworth M. H. , Mix A. C. , Kennedy A. M. , Bond B. J.
Published: April 2009

The Penman‐Monteith equation is often used to estimate transpiration, but an important limitation to this approach, especially for mountainous forested sites, is an accurate estimate of canopy conductance averaged over the area of interest (Gs). We propose a method for estimating watershed‐scale transpiration using estimates of Gs derived from measurements of stable isotopes. To estimate Gs, we first determined the isotopic composition of ecosystem respiration (δ13CER) as derived from the 12C:13C ratio of respired CO2 entrained within nocturnal cold air drainage flows exiting the base of the watershed. An isotope‐derived estimate of recent canopy conductance over the entire watershed (Gs‐I) was derived using biophysical models. To estimate daily average transpiration, we applied Gs‐I and other measured environmental variables to the Penman‐Monteith equation. The results were compared with an independent measure of transpiration using the heat dissipation method at four locations within the watershed. Considering the large number of assumptions required for both estimates of transpiration, the two estimates were remarkably similar. The relationship between the values derived by the two techniques was statistically significant (p value < 0.01), the slope of the line (slope = 1.7) was not statistically different from 1 (p value > 0.1), but the standard error was large (SE = 0.48). The results demonstrate that this technique holds promise, but the effects of potential limitations require further attention. The future research necessary to fully demonstrate the validity of this potentially promising method is discussed.
Hydrologic connectivity between landscapes and streams: Transferring reach‐ and plot‐scale understanding to the catchment scale
Authors: Jencso Kelsey G. , McGlynn Brian L. , Gooseff Michael N. , Wondzell Steven M. , Bencala Kenneth E. , Marshall Lucy A.
Published: April 2009

The relationship between catchment structure and runoff characteristics is poorly understood. In steep headwater catchments with shallow soils the accumulation of hillslope area (upslope accumulated area (UAA)) is a hypothesized first‐order control on the distribution of soil water and groundwater. Hillslope‐riparian water table connectivity represents the linkage between the dominant catchment landscape elements (hillslopes and riparian zones) and the channel network. Hydrologic connectivity between hillslope‐riparian‐stream (HRS) landscape elements is heterogeneous in space and often temporally transient. We sought to test the relationship between UAA and the existence and longevity of HRS shallow groundwater connectivity. We quantified water table connectivity based on 84 recording wells distributed across 24 HRS transects within the Tenderfoot Creek Experimental Forest (U.S. Forest Service), northern Rocky Mountains, Montana. Correlations were observed between the longevity of HRS water table connectivity and the size of each transect's UAA (r2 = 0.91). We applied this relationship to the entire stream network to quantify landscape‐scale connectivity through time and ascertain its relationship to catchment‐scale runoff dynamics. We found that the shape of the estimated annual landscape connectivity duration curve was highly related to the catchment flow duration curve (r2 = 0.95). This research suggests internal catchment landscape structure (topography and topology) as a first‐order control on runoff source area and whole catchment response characteristics.
Southern Australian rainfall and the subtropical ridge: Variations, interrelationships, and trends
Authors: Larsen S. H. , Nicholls N.
Published: April 2009

Monthly values of the latitude and intensity (mean maximum pressure) of the subtropical ridge (STR), averaged across Australian longitudes (105–155°E), have been related to variations and trends in rainfall over southern Australia (south of 30°S), for 1958–2005. There is an abrupt shift of latitude of the subtropical ridge over Australia at the onset of winter. In the cooler part of the year the intensity of the STR is more closely related to rainfall variations (and correlations between latitude and rainfall are a by‐product of the relationship of intensity with both latitude and rainfall), whereas in summer the latitude of the STR is more closely related to rainfall. The decline in southern Australian rainfall in recent decades (which has occurred principally in autumn) appears related to a trend towards a more intense STR, rather than a trend in the latitude of the STR.
Enhanced Cerebral Expression of MCT1 and MCT2 in a Rat Ischemia Model Occurs in Activated Microglial Cells
Authors: Moreira Tiago JTP , Pierre Karin , Maekawa Fumihiko , Repond Cendrine , Cebere Aleta , Liljequist Sture , Pellerin Luc
Published: April 2009

Monocarboxylate transporters (MCTs) are essential for the use of lactate, an energy substrate known to be overproduced in brain during an ischemic episode. The expression of MCT1 and MCT2 was investigated at 48 h of reperfusion from focal ischemia induced by unilateral extradural compression in Wistar rats. Increased MCT1 mRNA expression was detected in the injured cortex and hippocampus of compressed animals compared to sham controls. In the contralateral, uncompressed hemisphere, increases in MCT1 mRNA level in the cortex and MCT2 mRNA level in the hippocampus were noted. Interestingly, strong MCT1 and MCT2 protein expression was found in peri-lesional macrophages/microglia and in an isolectin B4+/S100β+ cell population in the corpus callosum. In vitro, MCT1 and MCT2 protein expression was observed in the N11 microglial cell line, whereas an enhancement of MCT1 expression by tumor necrosis factor-α (TNF-α) was shown in these cells. Modulation of MCT expression in microglia suggests that these transporters may help sustain microglial functions during recovery from focal brain ischemia. Overall, our study indicates that changes in MCT expression around and also away from the ischemic area, both at the mRNA and protein levels, are a part of the metabolic adaptations taking place in the brain after ischemia.
Time constant determination for electrical equivalent of biological cells
Authors: Dubey Ashutosh Kumar , Dutta-Gupta Shourya , Kumar Ravi , Tewari Abhishek , Basu Bikramjit
Published: April 2009

The electric field interactions with biological cells are of significant interest in various biophysical and biomedical applications. In order to study such important aspect, it is necessary to evaluate the time constant in order to estimate the response time of living cells in the electric field (E-field). In the present study, the time constant is evaluated by considering the hypothesis of electrical analog of spherical shaped cells and assuming realistic values for capacitance and resistivity properties of cell/nuclear membrane, cytoplasm, and nucleus. In addition, the resistance of cytoplasm and nucleoplasm was computed based on simple geometrical considerations. Importantly, the analysis on the basis of first principles shows that the average values of time constant would be around 2–3 μs, assuming the theoretical capacitance values and the analytically computed resistance values. The implication of our analytical solution has been discussed in reference to the cellular adaptation processes such as atrophy/hypertrophy as well as the variation in electrical transport properties of cellular membrane/cytoplasm/nuclear membrane/nucleoplasm.
Noncommutative reading of the complex plane through Delone sequences
Authors: Ali S. Twareque , Balkova Lubka , Curado E. M. F. , Gazeau J. P. , Rego-Monteiro M. A. , Rodrigues Ligia M. C. S. , Sekimoto K.
Published: April 2009

The Berezin–Klauder–Toeplitz (“anti-Wick”) quantization or “noncommutative reading” of the complex plane, viewed as the phase space of a particle moving on the line, is derived from the resolution of the unity provided by the standard (or Gaussian) coherent states. The construction of these states and their attractive properties are essentially based on the energy spectrum of the harmonic oscillator, that is, on the natural numbers. This work is an attempt for following the same path by considering sequences of non-negative numbers which are not “too far” from the natural numbers. In particular, we examine the consequences of such perturbations on the noncommutative reading of the complex plane in terms of its probabilistic, functional, and localization aspects.
Development of composite silver-polymer metamaterials
Authors: Mayy M. , Zhu G. , Barnakov Yu. A. , Noginov M. A.
Published: April 2009

We have synthesized and studied a series of composite silver-polymer photonic metamaterials with composition-tunable electric response. The dielectric constants of metamaterials, derived from the transmittance and reflectance spectra, were compared against several effective medium models. The demonstrated value of the real part of the dielectric constant ε′=12.8 at λ=2.4 μm is one of the highest in the near-to-midinfrared spectral range.
Thermal stability of semi-insulating property of Fe-doped GaN bulk films studied by photoluminescence and monoenergetic positron annihilation techniques
Authors: Kubota Masashi , Onuma Takeyoshi , Ishihara Yujiro , Usui Akira , Uedono Akira , Chichibu Shigefusa F.
Published: April 2009

The thermal stability of electrical resistivity (ρ) is one of the crucial functions of semi-insulating (SI) substrates. In this paper, we describe the thermal stability of SI property in Fe-doped GaN (GaN:Fe) films grown by hydride vapor phase epitaxy, in view of point defect chemistry by means of monoenergetic positron annihilation and photoluminescence (PL) measurements. PL spectra of GaN:Fe at 8 K exhibited broad emission bands in UV, blue, and yellow spectral regions, as well as a series of characteristic infrared peaks with a sharp zero-phonon line at 1.300 eV. A ρ value higher than 108 Ω⋅cm was obtained when the doping concentration of Fe, [Fe], exceeded the major shallow donor (Si) concentration (5×1017 cm−3). For those SI samples, the relative intensity of the yellow luminescence band at 2.2 eV, of which the origin has been attributed to Ga vacancies (VGa) and/or defect complexes composed of VGa and O, over the UV/blue emission was remarkably decreased. Simultaneously, the Doppler broadening S parameter for the positron annihilation measurement, which represents the size or concentration of negatively charged vacancy type point defects such as VGa, was decreased. The results are consistent with the increase in formation energy of VGa due to the downward shift of the Fermi level by Fe doping. The values of ρ, S, and W parameters that represents the fraction of positrons annihilated with core electrons, in the bulk region did not change remarkably while the positron diffusion length was increased by the annealing in N2 between 600 and 1050 °C. Although the defect concentration in uncapped surface region was increased remarkably by annealing at 1050 °C due to the surface decomposition, the present results indicate that GaN:Fe can be used as a thermally stable SI substrate for electronic devices because the surface does not decompose during the epitaxial growths of overlayers.
Polarity reversal of a magnetic vortex core by a unipolar, nonresonant in-plane pulsed magnetic field
Authors: Keavney D. J. , Cheng X. M. , Buchanan K. S.
Published: April 2009

We report the polarity reversal of a magnetic vortex core using a nonresonant in-plane pulsed magnetic field of arbitrary waveform studied using time-resolved x-ray photoemission electron microscopy and micromagnetic simulations. The imaging and simulations show that a 5 mT pulse, higher than the critical field for nonlinear effects, effectively leads to the randomization of the vortex core polarity. The micromagnetic simulations further show that the onset of stochastic core polarity randomization does not necessarily coincide with the critical reversal field, leading to a field window for predictable core reversal.
Residual stress and magnetic behavior of multiferroic CoFe2O4/Pb(Zr0.52Ti0.48)O3 thin films
Authors: Sim Chow Hong , Pan Z. Z. , Wang John
Published: April 2009

Multiferroic composite thin films consisting of CoFe2O4 (CFO) and Pb(Zr0.52Ti0.48)O3 (PZT) layers were deposited through a combined route of rf magnetron sputtering and sol gel on Pt(111)/TiO2/SiO2/Si substrates. The coupling effects in the bilayered thin film were studied by looking at the relationships among the crystallite orientation, magnetic behavior, and the in-plane residual stress. Phase selective residual stress analysis conducted by using x-ray method demonstrated a close correlation between the stress imposed on the PZT layer and its texture. A change in the PZT layer orientation from (1¯11) to (010) with the increasing layer thickness was observed in the multiferroic thin film as the system changes from an interface energy minimizing texture to a strain energy density minimizing texture. The CFO phase in the multiferroic thin films was preferably oriented in the (111) orientation. However, there is a change in magnetization as well as coercivity of the multiferroic thin films when the top PZT layer was varied in thickness. A close correlation between the magnetization and the in-plane stress in the CFO bottom layer imposed by the PZT film thickness was observed.
Laser ablated carbon plume flow dynamics under magnetic field
Authors: Pathak Kedar A. , Chandy Abhilash J.
Published: April 2009

The dynamics of a conducting laser ablated carbon plume flow in the ablation furnace typical for nanoparticle synthesis is investigated by numerical modeling. The effect of magnetic field on the flow is accounted through the Lorentz body force. The study begins with benchmark calculations of two simple test cases, the Kelvin–Helmholtz instability and Hartmann layer. The evolution of plume is then studied for longitudinal and transverse magnetic fields. It is observed that the transverse magnetic fields have more impact than longitudinal fields on plume evolution for this application. Ionization and heat capacity variation in the plume are accounted through the Saha equation and the Shomate equation, respectively. Multiple plume ejections typical for pulsed laser deposition of thin films are also discussed.