bluuebunny/crossref_metadata_2025 huggingface dataset:
The Rise and Fall of the Medical Gaze: The Political Economy of Immigrant Medical Inspection in Modern America
Authors: Fairchild Amy L.
Published: October 2006

Argument

In this paper I examine the mass medical inspections of immigrants to the United States from the 1890s through the 1920s. I show how, framed as it was not only by nativism and eugenics but also by national industrial imperatives and priorities, scientific medicine served dual purposes. On the one hand, the medical exam was a tool for managing cultural and biological threats to the nation. There were regional variations in medical inspections that reflected the politics of race. On the other hand, the medical exam played an important role in the process of building an unskilled, highly mobile labor force. The industrial demands of the nation provided a rationale for drawing and absorbing millions of European immigrants into the labor force. It was thus a distinct product of the political economy of immigration. It was this second function that characterized the exam for the majority of immigrants entering the nation.
Inoculating against Barbarism? State Medicine and Immigrant Policy in Turn-of-the-Century Argentina
Authors: Rodriguez Julia
Published: October 2006

Argument

The border in turn-of-the-century Argentina was a place of heightened anxiety. State officials ignored the nation's vast land borders and focused on the port, located in the capital city of Buenos Aires, which attracted nearly six million European immigrants in the decades after 1870. Federal authorities were seeking to attract new immigrants and yet they were terrified that opening their gates would allow entry among the potential citizenry a new category of “toxins” dangerous to the national body. The authorities hired physicians as gatekeepers to identify desirable and undesirable traits that went beyond the definition of communicable disease. Science and medicine appeared to provide a means of legitimating a variety of attempts by the state to control the makeup of the population; in reality, the state's power to inspect immigrants for disease, racial toxins, social upheaval, and political instability was minimized by realistic decisions to open borders and by a weak and limited ability to control the influx of people. Alongside calls for immigrant selection there coexisted a strong trend in political discourse that sought to build a unified, homogenous national culture by accepting and assimilating the foreign masses. Both approaches, however, had similar goals – the material progress of the nation, the advancement of Argentina's “civilization,” and the erasure of traces of “foreignness” among the new population.
Colonial Malariology, Medical Borders, and Sharing Scientific Knowledge in Mandatory Palestine
Authors: Sufian Sandy
Published: October 2006

Argument

This article focuses on the specific ways in which Zionist scientists studying malaria in Mandatory Palestine (1920–1947) presented their work to international scientific circles, moving between the transnational aspects and the local aspects of their work on malaria while suffusing that work with nationalist meanings. This slippery yet seemingly unproblematic movement between the general and the specific, between the colonial world and Palestine, was a necessary mechanism of scientific exchange. In the Zionist case the work on malaria for these scientists was both a marker of their belief in progress and also a sign of their devotion to a specific political and social project. The knowledge imparted by Zionist malariologists and the international reception it received lent scientific legitimacy to the Zionist project while it advanced the goals of settling the land and defining the communal borders within Palestine between the Arab population and the Jewish one. In this way, the Zionist anti-malaria project in Palestine holds a unique place in malaria research of the time.
Effect of massive gas hydrate formation on the water isotopic fractionation of the gas hydrate system at Hydrate Ridge, Cascadia margin, offshore Oregon
Authors: Tomaru Hitoshi , Torres Marta E. , Matsumoto Ryo , Borowski Walter S.
Published: October 2006

Because gas hydrate is preferentially enriched in the heavy water isotopes, the δ18O and δD values of pore waters collected from gas hydrate–bearing sediment can provide information on the abundance and mechanisms of gas hydrate formation. Pore waters sampled from deep‐seated (40 to 125 mbsf) gas hydrate deposits in Hydrate Ridge during ODP Leg 204 show depletion in dissolved Cl− and enrichments in 18O and D due to gas hydrate destabilization during core recovery. The oxygen and hydrogen isotopic fractionation factors (αO = 1.0025 and αH = 1.022) estimated from an extensive data set (n = 30 samples) correspond to experimentally determined values. In contrast, pore waters from shallow samples (<25 mbsf) at the ridge summit (n = 32) are highly enriched in dissolved Cl− and depleted in 18O and D, consistent with formation of massive gas hydrate deposits at rates faster than those at which these anomalies would be removed by advection or diffusion. The water isotopic fractionation factors in the brine are significantly lower than those experimentally determined, with αO of 1.0010 (average value of 1.0012) and αH of 1.008 (average value of 1.008). We discuss several factors that may be causing this anomalous fractionation and suggest that low gas occupancy in hydrate lattice (high hydration number) may be responsible for the observed small fractionation. If this were the case, the oxygen and hydrogen fractionation may serve as an indicator of hydration number during formation of gas hydrate in natural systems.
Snow characterization at a global scale with passive microwave satellite observations
Authors: Cordisco E. , Prigent C. , Aires F.
Published: October 2006

The sensitivity of passive microwave satellite observations to snow characteristics is evaluated, between 19 and 85 GHz, for a winter season, for the Northern Hemisphere. The surface emissivities derived from the Special Sensor Microwave/Imager measurements are systematically compared with in situ snow measurements at 2784 stations, in North America and Eurasia. In addition, coincident satellite responses from active microwave sensors (ERS scatterometer) and visible observations (AVHRR) are also analyzed. Vegetation interferes with the signal that is received by the satellites. Snow emissivities also react to scattering by the snow grain growth that is related to the snow metamorphism during the winter. This phenomenon increases with frequency and is already very sensitive at 37 GHz. Passive microwaves at high frequency (85 GHz) are very sensitive to the presence of snow on the ground, even for very low snow depth. None of the tested satellite measurements is well correlated to the snow depth at a global scale, making snow depth retrieval from these observations very difficult on a global basis. The sensitivity of the satellite observations to snow characteristics depends on local conditions. To partly alleviate these difficulties, a neural network inversion scheme based on local statistics is developed to combine satellite observations, in situ measurements, and land surface model outputs. The combination of different wavelengths partly limits the ambiguities related to the individual sensitivity of each satellite observation to the various sources of variabilities. The final retrieval algorithm is compatible with an assimilation strategy that would better constrain the behavior of surface models. Finally, a clustering algorithm is applied to the suite of satellite observations and clearly shows a strong sensitivity to the snow characteristics and metamorphism during the winter. Characterization of the snowpack using satellite observation classification can yield qualitative information for snow model parameterization.
Isotopic composition of the precipitations in the central Mediterranean: Origin marks and orographic precipitation effects
Authors: Liotta Marcello , Favara Rocco , Valenza Mariano
Published: October 2006

The isotopic composition of the rainfall in northwestern Sicily (Italy, central Mediterranean) was investigated in the period February 2002 to March 2003. A rain gauge network was installed and sampled monthly. The monthly values of the D and 18O ratios showed a wide range that reflected seasonal climatic variations. Mean weighted values were used to define an isotopic model of precipitation. Temporal variations in deuterium excess were also investigated. Using mean volume weighted values, the Local Meteoric Water Line (LMWL) can be represented by the equation: δD = 4.7δ18O − 8.2 (r2 = 0.96). Deuterium excess (d = δD − 8δ18O) was found to be strongly related to orography. The coastline samples were characterized by mean weighted deuterium excess values close to 12.5‰; samples from inland areas showed values of 16‰, while samples taken from the main reliefs showed values close to 19‰. In inland areas, isotopic exchange between raindrops and moisture could shift the deuterium excess values slightly. On the higher reliefs, the interaction between falling raindrops and orographic clouds could shift the deuterium excess values significantly. The low slope of the LMWL could be referred to the high deuterium excess values of the higher sites and is related to orographic precipitation rather than to evaporation processes during the fall of the raindrops. The results obtained suggest that local orographic features may significantly change the isotopic composition of precipitation.
High‐speed measurements of small‐scale features in sprites: Sizes and lifetimes
Authors: Marshall R. A. , Inan U. S.
Published: October 2006

We report on the results of observations with a combination of high‐speed and telescopic imaging to capture high spatial resolution images of sprite streamers and beads at high frame rates, revealing the evolution and propagation of these structures on a decameter scale at millisecond and higher resolution. In July and August 2004, sprites were observed from Langmuir Laboratory, in the mountains of New Mexico, using a >1000 frames‐per‐second intensified CCD imager mounted to a Dobsonian reflecting telescope. We present a number of examples of sprite features, along with photometric data on sprites and sprite halos, taken with the Wide‐angle Array for Sprite Photometry (WASP). Results show a variety of structures, including evidence of formation and evolution of both streamers and beads. Examples and statistics presented indicate that most bead structures have sizes of 10–300 m, similar to previous telescopic observations, and endure typically for a few milliseconds to 10 ms, with rare cases of up to 50 ms. Similarly, streamer‐like structures are observed to have diameters of 10–300 m but persist for shorter timescales, typically 2–3 ms, with occasional cases of up to 10 ms. Attempts to measure propagation of streamers indicate that higher frame rates are required in order to observe speeds on the order of previous wide‐field‐of‐view observations and modeling predictions.
Time variations of the regional evapotranspiration rate from Gravity Recovery and Climate Experiment (GRACE) satellite gravimetry
Authors: Ramillien G. , Frappart F. , Güntner A. , Ngo‐Duc T. , Cazenave A. , Laval K.
Published: October 2006

Since its launch in March 2002, the Gravity Recovery and Climate Experiment (GRACE) mission has been measuring the global time variations of the Earth's gravity field with a current resolution of ∼500 km. Especially over the continents, these measurements represent the integrated land water mass, including surface waters (lakes, wetlands and rivers), soil moisture, groundwater, and snow cover. In this study, we use the GRACE land water solutions computed by Ramillien et al. (2005a) through an iterative inversion of monthly geoids from April 2002 to May 2004 to estimate time series of basin‐scale regional evapotranspiration rate and associated uncertainties. Evapotranspiration is determined by integrating and solving the water mass balance equation, which relates land water storage (from GRACE), precipitation data (from the Global Precipitation Climatology Centre), runoff (from a global land surface model), and evapotranspiration (the unknown). We further examine the sensibility of the computation when using different model runoff. Evapotranspiration results are compared to outputs of four different global land surface models. The overall satisfactory agreement between GRACE‐derived and model‐based evapotranspiration prove the ability of GRACE to provide realistic estimates of this parameter.
Infrasound events detected with the Southern California Seismic Network
Authors: Cochran E. S. , Shearer P. M.
Published: October 2006

We examine continuous data from the Southern California Seismic Network from 2003 and identify infrasound acoustic waves from 76 previously undetected events. Using waveform cross‐correlation of the signal envelope functions, we determine their relative arrival times and estimate source locations. The waves travel at acoustic speeds of 320 m/s and are observed in seismic records up to 450 km from their probable source locations off the west coast of southern California. The dominant daylight occurrence of the events points to a man‐made source related to military activity. The events are mostly recorded in the winter and spring when atmospheric conditions trap acoustic energy near the Earth's surface and favor propagation to the west. These results suggest that data from regional and global seismic networks can supplement observations from infrasound arrays for Comprehensive Test Ban Treaty monitoring and geophysical applications such as volcano monitoring, bolide detection, atmospheric acoustic sources and atmospheric tomography.
Remote forcing contribution to storm‐induced sea level rise during Hurricane Dennis
Authors: Morey Steven L. , Baig Stephen , Bourassa Mark A. , Dukhovskoy Dmitry S. , O'Brien James J.
Published: October 2006

Numerical model experiments are conducted to address the previously unexplained anomalously high storm surge along the Florida coast of Apalachee Bay during Hurricane Dennis (2005). The 2–3 m surge observed during this storm cannot be obviously explained by the relatively weak local winds over this bay 275 km east of the storm center. Realistic and idealized numerical experiments demonstrate that the along‐shore winds to the east of the storm center built a high sea level anomaly along the coast which traveled northward to Apalachee Bay as a topographic Rossby wave. The wave was amplified as the storm moved nearly parallel to the shelf and at comparable speed to the wave phase speed. These results suggest that enlarging the domain of the storm surge forecasting models can improve the surge forecast for a storm moving along a similar track, and have now been applied to operational use.
Thermal imaging on simulated faults during frictional sliding
Authors: Mair Karen , Renard François , Gundersen Olav
Published: October 2006

Heating during frictional sliding is a major component of the energy budget of earthquakes and represents a potential weakening mechanism. It is therefore important to investigate how heat dissipates during sliding on simulated faults. We present results from laboratory friction experiments where a halite (NaCl) slider held under constant load is dragged across a coarse substrate. Surface evolution and frictional resistance are recorded. Heat emission at the sliding surface is monitored using an infra‐red camera. We demonstrate a link between plastic deformations of halite and enhanced heating characterized by transient localized heat spots. When sand ‘gouge’ is added to the interface, heating is more diffuse. Importantly, when strong asperities concentrate deformation, significantly more heat is produced locally. In natural faults such regions could be nucleation patches for melt production and hence potentially initiate weakening during earthquakes at much smaller sliding velocities or shear stress than previously thought.
Air‐sea humidity effects on the generation of tropical Atlantic SST anomalies during the ENSO events
Authors: Chikamoto Yoshimitsu , Tanimoto Youichi
Published: October 2006

After the mature stage of the ENSO events in the boreal winter, SST and latent heat flux anomalies over the tropical Atlantic during the following spring show large amplitude north of the equator but small one south of the equator. The linear decomposition analyses of the latent heat flux anomalies indicate that the contribution from wind speed anomaly shows an equatorial antisymmetric structure with same magnitude but opposite polarity between north and south of the equator, while the contribution from anomalous air‐sea humidity difference counters to that from wind speed anomaly south of the equator. These results suggest an important role of anomalous air‐sea humidity difference on forming latent heat flux anomaly and significantly modifies the conventional view of wind speed as the dominant effect in ENSO‐induced tropical Atlantic SST changes.
Novel improvements to magnetospheric tomography using MHD
Authors: Dyrud Lars P. , Murr David L.
Published: October 2006

Over the past decade, radio tomographic techniques have seen increasing use within space science, both in practice, with ionospheric reconstruction, and theoretically as a tool for remote sensing magnetospheric plasmas. The promise of this technique for use in the magnetosphere was greatly enhanced with the introduction of combined Faraday rotation and phase or group delay radio tomography. As measurables these techniques provide distributions in space and time of electron density ne and magnetic field . Given these measured quantities, this paper provides a theoretical framework for further derivation of additional parameters, such as plasma temperature, based upon MHD relations. Additionally, we show how using the physical constraint · = 0 to regularize the reconstructions of magnetic field yields superior reconstructions with fewer measurements and provides a physical and effective method for incorporating in situ magnetometer measurements. Specifically, we find that including this regularization often reduces RMS errors in magnetic field reconstructions by a factor of 3. This simple regularization, especially when combined with in situ magnetometer measurements, is so powerful that it may influence future designs of a magnetospheric tomography mission.
Energetic oxygen atoms in the polar geocorona
Authors: Shematovich V. I. , Bisikalo D. V. , Gérard J.‐C.
Published: October 2006

The role of the auroral sources induced by the electron and proton precipitation in the formation of the hot oxygen corona in the polar upper atmosphere is studied. It is found that both electron precipitation through exothermic chemistry and proton precipitation through atmospheric sputtering significantly contribute to the population of the hot oxygen geocorona. It is also found that only atmospheric sputtering results in the formation of the escape flux of energetic oxygen atoms, providing an important source of heavy atoms for the magnetosphere. The exothermic chemistry induced by the electron precipitation and/or by the absorption of the solar UV radiation is operating continuously in the polar upper atmosphere and results in a steady population of the very near‐Earth environment by suprathermal oxygen atoms with energies below a few eV. By contrast, atmospheric sputtering by magnetospheric protons provides a more variable contribution, strongly coupled with the cusp region. It produces the more energetic oxygen atoms that populate the external regions of the hot oxygen geocorona. The results of calculations are in a good agreement with the analysis of the low‐latitude perigee Low Energy Neutral Atom (LENA) images showing that the instrument signal consists of low to medium energy (5–30 eV) oxygen atoms produced in and near the cusp region. The more energetic (>30 eV) fraction of energetic oxygen atoms produced by the ion‐induced atmospheric sputtering could be responsible for the energetic neutrals observed by the instrument far away from the cusp or oval regions. The total escape flux of oxygen atoms associated with atmospheric sputtering by protons is found about 8 × 1023 s−1; therefore this mechanism may provide a substantial contribution to the magnetospheric oxygen population.
Quasi‐monochromatic inertia‐gravity waves in the lower stratosphere from MST radar observations
Authors: Nastrom G. D. , Eaton F. D.
Published: October 2006

The frequency of occurrence of quasi‐monochromatic oscillations with periods near the inertial period is examined using hourly mean wind observations from the MST radars at White Sands Missile Range, New Mexico, and Vandenberg Air Force Base, California, spanning 6 years and 4 years, respectively. Power spectral analyses show that the energy levels near the inertial frequency during summer are nearly constant with altitude from about 12 km up to the highest altitude available, about 20 km, while energy levels at lower frequencies decrease with altitude. This decrease leads to a relative enhancement of energy near the inertial frequency. During winter the relative enhancement near the inertial frequency is much smaller. Results from least squares curve fitting used to find the percent of wind variance explained (PEV) by a single wave over data blocks 72 hours long and 2 km deep indicate that a quasi‐monochromatic oscillation is present when PEV ≥ 25%. During summer in the stratosphere over 50% of the cases have PEV ≥ 25%. The best fit waveform has mean period near 21 hours and vertical wavelength near 3 km. The wind vectors exhibit anticyclonic rotation in time and with height, consistent with upward propagating gravity waves. The mean ratio of the intrinsic to the inertial frequency is about 1.3 in this data set, and the associated mean horizontal wavelength of these waves is slightly over 1000 km.
Actions of ZD0947, a novel ATP‐sensitive K+channel opener, on membrane currents in human detrusor myocytes
Authors: Aishima M , Tomoda T , Yunoki T , Nakano T , Seki N , Yonemitsu Y , Sueishi K , Naito S , Ito Y , Teramoto N
Published: October 2006

Background and purpose:

ATP‐sensitive K+channels (KATPchannels) play important roles in regulating the resting membrane potential of detrusor smooth muscle. Actions of ZD0947, a novel KATPchannel opener, on both carbachol (CCh)‐induced detrusor contractions and membrane currents in human urinary bladder myocytes were investigated.

Experimental approach:

Tension measurements and patch‐clamp techniques were utilized to study the effects of ZD0947 in segments of human urinary bladder. Immunohistochemistry was also performed to detect the expression of the sulphonylurea receptor 1 (SUR1) and the SUR2B antigens in human detrusor muscle.

Key results:

ZD0947 (≥0.1 μM) caused a concentration‐dependent relaxation of the CCh‐induced contraction of human detrusor, which was reversed by glibenclamide. The rank order of the potency to relax the CCh‐induced contraction was pinacidil>ZD0947>diazoxide. In conventional whole‐cell configuration, ZD0947 (≥1 μM) caused a concentration‐dependent inward K+current which was suppressed by glibenclamide at ‐60 mV. When 1 mM ATP was included in the pipette solution, application of pinacidil or ZD0947 caused no inward K+current at ‐60 mV. Gliclazide (≤1 μM), a selective SUR1 blocker, inhibited the ZD0947‐induced currents (Ki=4.0 μM) and the diazoxide‐induced currents (high‐affinity site,Ki1=42.4 nM; low‐affinity site,Ki2=84.5 μM) at ‐60 mV. Immunohistochemical studies indicated the presence of SUR1 and SUR2B proteins, which are constituents of KATPchannels, in the bundles of human detrusor smooth muscle.

Conclusions and Implications:

These results suggest that ZD0947 caused a glibenclamide‐sensitive detrusor relaxation through activation of glibenclamide‐sensitive KATPchannels in human urinary bladder.

British Journal of Pharmacology(2006)149, 542–550. doi:10.1038/sj.bjp.0706893
β3‐Adrenoceptor agonist stimulation of the Na+,K+‐pump in rat skeletal muscle is mediated by β2‐ rather than β3‐adrenoceptors
Authors: Murphy K T , Bundgaard H , Clausen T
Published: October 2006

Background and purpose:

In cardiac muscle, BRL 37344, a selective β3‐adrenoceptor agonist, activates the Na+,K+‐pump via NO signalling. This study investigated whether BRL 37344 also activates the Na+,K+‐pump via β3‐adrenoceptors in skeletal muscle.

Experimental approach:

Isolated rat soleus muscles were incubated between 1 and 60 min in buffer. Intracellular Na+,K+ content and Na+,K+‐pump activity were measured using flame photometry and ouabain‐suppressible 86Rb+ uptake, respectively. Additional muscles were mounted on force transducers and stimulated (60 Hz for 2 s) every 10 min.

Key results:

BRL 37344 (10‐8‐10‐5 M) induced a concentration‐ and time‐dependent reduction in intracellular Na+, and increased ouabain‐suppressible 86Rb+ uptake by up to 112%. BRL 37344‐induced reductions in intracellular Na+ were blocked by the β1/β2‐adrenoceptor antagonist, nadolol (10‐7 M), and the β2‐adrenoceptor antagonist, ICI 118,551 (10‐7‐10‐5 M), but not by β3‐ or β1‐adrenoceptor antagonists, SR 59230A (10‐7 M) and CGP 20712A (10‐7‐10‐5 M), respectively. Another β3‐adrenoceptor agonist, CL 316,243, did not alter intracellular Na+. BRL 37344‐induced reductions in intracellular Na+ were not blocked by L‐NAME, an NOS inhibitor, or ODQ, a guanylyl cyclase inhibitor. The NO donors, SNP and SNAP, did not alter intracellular Na+. BRL 37344 rapidly recovered force in muscles depressed by high [K+]o, an effect that was blocked by nadolol, but not L‐NAME.

Conclusions and implications:

In rat soleus muscle, the β3‐adrenoceptor agonist BRL 37344 stimulated the Na+,K+‐pump via β2‐adrenoceptors. A more selective β3‐adrenoceptor agonist did not affect Na+, K+ homeostasis in skeletal muscle. NO did not seem to mediate Na+,K+‐pump stimulation in skeletal muscle.

British Journal of Pharmacology (2006) 149, 635–646. doi:10.1038/sj.bjp.0706896
Pharmacological and molecular evidence for the involvement of Kv4.3 in ultra‐fast activating K+ currents in murine portal vein myocytes
Authors: Yeung S Y M , Ohya S , Sergeant G P , Pucovský V , Greenwood I A
Published: October 2006

Background and purpose:

The aim of this study was to determine the molecular identity of a transient K+ current (termed I
UF) in mouse portal vein myocytes using pharmacological and molecular tools.

Experimental approach:

Whole cell currents were recorded using the ruptured patch con from either acutely dispersed single smooth muscle cells from the murine portal vein or human embryonic kidney cells. Reverse transcriptase polymerase reaction (RT‐PCR) experiments were undertaken on RNA isolated from mouse portal vein using primers specific for various voltage‐dependent K+ channels, auxillary subunits and calcium‐binding proteins. Immunocytochemistry was undertaken using an antibody specific for Kv4.3.

Key results:

I
UF had a mean amplitude at +40 mV of 558±50 pA (n=32) with a mean time to peak at +40 mV of ∼4 ms. I
UF activated and inactivated with a half maximal voltage of ‐12±2 mV and ‐85±2 mV, respectively. I
UF was relatively resistant to 4‐aminopyridine (5 mM produced 30±6 % block at +20 mV) but was inhibited effectively by flecainide (IC50 value was 100nM) and phrixotoxin II. This pharmacological profile is consistent with I
UF being comprised of Kv4.x proteins and this is supported by the results from the quantitative PCR and immunocytochemical experiments.

Conclusions and implications:

These data represent a rigorous investigation of the molecular basis of vascular transient K+ currents and implicates Kv4.3 as a major component of the channel complex.

British Journal of Pharmacology (2006) 149, 676–686. doi:10.1038/sj.bjp.0706903
What is the significance of vascular hydrogen sulphide (H2S)?
Authors: O'Sullivan S E
Published: October 2006

The important role of nitric oxide (NO) in the regulation of vascular tone has been well studied. By contrast, the vascular significance of another gaseous mediator, hydrogen sulphide (H2S), is still poorly understood. A study published in this issue of the British Journal of Pharmacology now provides evidence that in addition to the vasorelaxant effects of H2S reported in vitro, low concentrations of H2S also cause arterial vasoconstriction, reverse NO‐mediated vasorelaxation and cause an NO‐dependent pressor effect in vivo. This commentary discusses the implications and questions raised by these results.

British Journal of Pharmacology (2006) 149, 609–610. doi:10.1038/sj.bjp.0706907
Cardiovascular responses to combined treatment with selective monoamine oxidase type B inhibitors and L‐DOPA in the rat
Authors: Finberg J P M , Gross A , Bar‐Am O , Friedman R , Loboda Y , Youdim M B H
Published: October 2006

Background and purpose:

Postural hypotension is a common side‐effect of L‐DOPA treatment of Parkinson's disease, and may be potentiated when L‐DOPA is combined with selegiline, a selective inhibitor of monoamine oxidase B (MAO‐B). Rasagiline is a new, potent and selective MAO‐B inhibitor, which does not possess the sympathomimetic effects of selegiline. We have studied the effects of these selective MAO inhibitors, L‐DOPA and dopamine on the cardiovascular system of the rat.

Experimental approach:

Blood pressure and heart rate was measured in conscious rats following acute or chronic administration of rasagiline, selegiline and L‐DOPA, by comparison with the selective MAO‐A inhibitor clorgyline, or the MAO‐A/B inhibitor tranylcypromine. Cardiovascular responses, catecholamine release, and modification of pressor response to dopamine were studied in pithed rats.

Key results:

In conscious rats neither rasagiline nor selegiline caused significant potentiation of the effects of L‐DOPA (50, 100, 150 mg.kg−1) on blood pressure or heart rate at doses which selectively inhibited MAO‐B, but L‐DOPA responses were potentiated by clorgyline and tranylcypromine. In rats treated twice daily for 8 days with L‐DOPA and carbidopa, selegiline (5 mg.kg−1) but not rasagiline (0.2 mg.kg−1) caused a significant hypotensive response to L‐DOPA and carbidopa, although both drugs caused similar inhibition of MAO‐A and MAO‐B. In pithed rats, selegiline but not rasagiline increased catecholamine release and heart rate, and potentiated dopamine pressor response at MAO‐B selective dose.

Conclusions and implications:

The different responses to the two MAO‐B inhibitors may be explained by the amine releasing effect of amphetamine metabolites formed from selegiline.

British Journal of Pharmacology (2006) 149, 647–656. doi:10.1038/sj.bjp.0706908
Blood–brain distribution of morphine‐6‐glucuronide in sheep
Authors: Villesen H H , Foster D J R , Upton R N , Christrup L L , Somogyi A A , Martinez A , Grant C
Published: October 2006

Background and purpose:

At present there are few data regarding the rate and extent of brain–blood partitioning of the opioid active metabolite of morphine, morphine‐6‐glucuronide (M6G). In this study the cerebral kinetics of M6G were determined, after a short‐term intravenous infusion, in chronically instrumented conscious sheep.

Experimental approach:

Five sheep received an intravenous infusion of M6G 2.2 mg kg‐1over a four‐minute period. Non‐linear mixed‐effects analysis, with hybrid physiologically based kinetic models, was used to estimate cerebral kinetics from the arterio‐sagittal sinus concentration gradients and cerebral blood flow measurements.

Key results:

A membrane limited model was selected as the final model. The blood‐brain equilibration of M6G was relatively slow (time to reach 50% equilibration of the deep compartment 5.8 min), with low membrane permeability (PS, population mean, 2.5 ml min‐1) from the initial compartment (V1, 13.7 ml) to a small deep distribution volume (V2) of 18.4 ml. There was some between‐animal variability (%CV) in the initial distribution volume (29%), but this was not identified for PS or V2.

Conclusion and Implications:

Pharmacokinetic modelling of M6G showed a delayed equilibration between brain and blood of a nature that is primarily limited by permeability across the blood‐brain‐barrier, in accordance with its physico‐chemical properties.

British Journal of Pharmacology(2006)149, 754–760. doi:10.1038/sj.bjp.0706916
AM‐36 modulates the neutrophil inflammatory response and reduces breakdown of the blood brain barrier after endothelin‐1 induced focal brain ischaemia
Authors: Weston R M , Jarrott B , Ishizuka Y , Callaway J K
Published: October 2006

Background and purpose:

Following transient focal stroke, rapid accumulation and activation of neutrophils in the ischaemic region is deleterious due to release of reactive oxygen species and myeloperoxidase (MPO). The purpose of this study was to examine whether AM‐36, both a Na+ channel blocker and an antioxidant, afforded neuroprotection by modulating neutrophil accumulation into brain, following endothelin‐1 (ET‐1) induced middle cerebral artery occlusion (MCAo) in conscious rats.

Experimental approach:

AM‐36 was administered at 3 and 24 h after ET‐1‐induced MCAo. Functional recovery was determined using grid‐walking and cylinder tests. Image analysis of brain sections was used to determine infarct volume. The effect of AM‐36 on neutrophil infiltration and their interaction with macrophages was examined in rats at 48 h following MCAo by both an MPO assay and double‐label immunofluorescence. Blood brain barrier (BBB) breakdown was measured by the area stained by intravenous Evans Blue.

Key results:

AM‐36 reduced functional deficits in both tests such that no difference existed from pre‐ischaemic values at 48 h. Neutrophil infiltration, assessed by MPO activity, and infarct volume were significantly reduced following AM‐36 administration by 54 and 60% respectively. Similarly, immunofluorescence revealed that AM‐36 reduced neutrophil infiltration by ∼50% in selected brain regions, when compared to controls, and also modulated macrophage phagocytosis of neutrophils. Breakdown of the BBB was significantly reduced by 60% following AM‐36 treatment.

Conclusions and Implications:

These findings suggest that AM‐36 can directly modulate the neutrophil inflammatory response and reduce BBB breakdown following MCAo.

British Journal of Pharmacology (2006) 149, 712–723. doi:10.1038/sj.bjp.0706918
Influence of photon reabsorption on quasi-steady-state photoluminescence measurements on crystalline silicon
Authors: Trupke T.
Published: October 2006

The influence of reabsorption of spontaneously emitted photons within silicon samples on quasi-steady-state photoluminescence lifetime measurements and on implied current voltage curves obtained from photoluminescence is analyzed. It is shown that experimental artifacts resulting from reabsorption can generally be expected to be small and that they are expected only if the relative carrier density profile varies strongly with injection level. Such strong variations in the relative carrier density profile are shown to be expected only if the effective minority carrier lifetime varies with injection level over the range from 1to50μs which even then results in an under- or overestimation of the effective minority carrier lifetime by less than 20%.
Energy transfer between azulene and krypton: Comparison between experiment and computation
Authors: Bernshtein V. , Oref I.
Published: October 2006

Trajectory calculations of collisional energy transfer between excited azulene and Kr are reported, and the results are compared with recent crossed molecular beam experiments by Liu et al. [J. Chem. Phys. 123, 131102 (2005); 124, 054302 (2006)]. Average energy transfer quantities are reported and compared with results obtained before for azulene-Ar collisions. A collisional energy transfer probability density function P(E,E′), calculated at identical initial conditions as experiments, shows a peak at the up-collision branch of P(E,E′) at low initial relative translational energy. This peak is absent at higher relative translational energies. There is a supercollision tail at the down-collision side of the probability distribution. Various intermolecular potentials are used and compared. There is broad agreement between experiment and computation, but there are some differences as well.
A crossed-beam study of the F+HD→HF+D reaction: The resonance-mediated channel
Authors: Lee Shih-Huang , Dong Feng , Liu Kopin
Published: October 2006

This is the last report of our extensive studies on the title reaction. Presented here are the state-to-state differential cross section determinations at 11 collision energies, ranging from 1.30to4.53kcal∕mol. Together with previously reported results at six lower energies (0.4–1.18kcal∕mol), this perhaps represents one of the most comprehensive set of data from a single investigation for any chemical reaction. The information contents of this set of data are examined in detail, from which the dynamical consequences of reactive resonances are elucidated. Qualitative interpretations of some of the major findings are proposed. Observations that need further theoretical investigations for better physical understanding are pointed out.
State-to-state quantum reactive scattering for four-atom chemical reactions: Differential cross section for the H+H2O→H2+OH abstraction reaction
Authors: Zhang Dong H.
Published: October 2006

The time-dependent wave packet method was extended to calculate the state-to-state differential cross section for the title four-atom abstraction reaction with H2O in the ground rovibrational state. One spectator OH bond length was fixed in the study, but the remaining five degrees of freedom were treated exactly. It was found that (a) the differential cross section changes from being strongly backward peaked at low collision energy to sideward scattering at E=1.4eV, and (b) the rotational state-resolved differential cross section for H2 differs substantially from that for OH.
Photodissociation and photoisomerization of α-fluorotoluene and 4-fluorotoluene in a molecular beam
Authors: Huang Cheng-Liang , Jiang Jyh-Chiang , Dyakov Yuri A. , Lin Ming-Fu , Tseng Chien-Ming , Lin S. H. , Lee Yuan T. , Ni Chi-Kung
Published: October 2006

The photodissociation of jet-cooled α-fluorotoluene and 4-fluorotoluene at 193 and 248nm was studied using vacuum ultraviolet (vuv) photoionization/multimass ion imaging techniques as well as electron impact ionization/photofragment translational spectroscopy. Four dissociation channels were observed for α-fluorotoluene at both 193 and 248nm, including two major channels C6H5CH2F→C6H5CH2 (orC7H7)+F and C6H5CH2F→C6H5CH (orC7H6)+HF and two minor channels C6H5CH2F→C6H5CHF+H and C6H5CH2F→C6H5+CH2F. The vuv wavelength dependence of the C7H7 fragment photoionization spectra indicates that at least part of the F atom elimination channel results from the isomerization of α-fluorotoluene to a seven-membered ring prior to dissociation. Dissociation channels of 4-fluorotoluene at 193nm include two major channels C6H4FCH3→C6H4FCH2+H and C6H4FCH3→C6H4F+CH3 and two minor channels C6H4FCH3→C6H5CH2 (orC7H7)+F and C6H4FCH3→C6H5CH (orC7H6)+HF. The dissociation rates for α-fluorotoluene at 193 and 248nm are 3.3×107 and 5.6×105s−1, respectively. The dissociation rate for 4-fluorotoluene at 193nm is 1.0×106s−1. An ab initio calculation demonstrates that the barrier height for isomerization from α-fluorotoluene to a seven-membered ring isomer is much lower than that from 4-fluorotoluene to a seven-membered ring isomer. The experimental observed differences of dissociation rates and relative branching ratios between α-fluorotoluene and 4-fluorotoluene may be explained by the differences in the six-membered ring to seven-membered ring isomerization barrier heights, F atom elimination threshold, and HF elimination threshold between α-fluorotoluene and 4-fluorotoluene.
Three-dimensional model of x-ray induced microchannel plate output
Authors: Harding E. C. , Drake R. P.
Published: October 2006

Microchannel plates are an important component in a type of imaging diagnostic known as an x-ray framing camera, used in x-ray radiography of high-energy-density physics experiments. A microchannel plate is responsible for detecting x rays and then converting them into amplified bursts of electrons, which are then imaged onto a phosphor-coated fiber optic screen. We present the preliminary development of a three-dimensional model of a single microchannel plate channel in attempt to simulate the pulse height distribution of the microchannel plate electron output. Using a novel technique, initial simulations are compared with experimental data from an ungated x-ray framing camera.
Calibration and operational experience with the JET motional Stark effect diagnostic
Authors: Hawkes N. C. , Brix M. ,   JET EFDA Contributors
Published: October 2006

Motional Stark effect measurements of the magnetic field pitch angle on JET present several difficulties most serious of which is that the injection systems consist of more than one source, each with a different motional stark effect (MSE) angle. Attempts to describe the net polarization angle, within the EFIT equilibrium code, using the weighted sum of Stokes vectors, have proved inaccurate. Instead we rely on spectrally isolating the emission of a single source. Beam power modulation is helpful in differentiating background polarized light, but this technique fails in the presence of strong edge localized mode (ELMs). Calibration is difficult because of the presence of a mirror in the optical system. The mirror introduces a large optical phase shift which means that the polarimeter has to resolve circular as well as linear polarized components. Basic calibration is carried out off the tokamak using a motorized rotary encoder stage and a six-parameter physical model of the optical and electronic systems. This is readjusted using plasma emission, for mirror operation at 300 °C. Some of the operating experience obtained with the JET MSE diagnostic will be relevant to ITER, although the lack of independent power or voltage control of the ITER injectors is seen as the chief challenge facing the ITER MSE design.
Solid-density plasma characterization with x-ray scattering on the 200J Janus laser
Authors: Neumayer P. , Gregori G. , Ravasio A. , Koenig M. , Price D. , Widmann K. , Bastea M. , Landen O. L. , Glenzer S. H.
Published: October 2006

We present collective x-ray scattering (CXS) measurements using a chlorine He-α x-ray source pumped with less than 200J of laser energy. The experimental scattering spectra show plasmon resonances from shocked and radiatively heated samples. These experiments use only 1012 x-ray photons at the sample of which 10−5 have been scattered and detected with a highly efficient curved crystal spectrometer. Our results demonstrate that x-ray scattering is a viable technique on smaller laser facilities, making CXS measurements accessible to a broad scientific community.
Development of fast helium beam emission spectroscopy on MST
Authors: Ahn J.-W. , Craig D. , Fiksel G. , Den Hartog D. J. , Anderson J. K. , O’Mullane M. G.
Published: October 2006

Emission from an energetic neutral helium beam has been investigated as a potential localized diagnostic for the plasma parameters. A collisional-radiative model in atomic data and analysis structure was used to estimate evolutions of the atomic level populations in the beam and the beam emission intensities. It has been found that singlet lines are insensitive to the local metastable fraction and thus have been chosen to construct line ratios. The Te and ne dependences of the ratios were investigated and some have been found to be sensitive to the density, but no ratios show significant sensitivity to the temperature in the range of interest for Madison symmetric torus. The theoretically expected line ratios are compared with the experimental results. It is shown that local density measurements may be possible using the singlet line ratio technique.
Thin gap chamber performance tests under several MeV neutron sources
Authors: Ochi Atsuhiko , Kiyamura Hironori , Kaneko Junichi , Ohshita Hidetoshi , Takeshita Tohru , Tanaka Shuji , Iwasaki Hiroyuki , Ochiai Kentaro , Nakao Makoto
Published: October 2006

Thin gap chamber (TGC) is a very thin multiwire proportional chamber of only a few millimeters. It has a quick response (about 20ns), and its production costs are relatively low. TGCs have been used as large area detectors in high energy physics such as Large Electron-Positron collider (LEP) and will be used in the Large Hadron collider (LHC) experiment. However, the characteristics of TGCs under neutrons are not yet clearly understood. As the energy deposits of several MeV neutrons in TGCs are large, the possible effect of these deposits on the operation of the detector is a concern. We studied TGC performance in relation to efficiency, charge distribution, and operation stability using several gas mixtures (CO2∕n-pentane and CF4∕n-pentane) with 2.5 and 14MeV neutron sources at Fusion Neutronics Source (FNS) in Japan Atomic Energy Agency. Operation stability using a CF4 based gas was more than 100 times greater than with CO2 based gas, while the minimum ionizing particle signal gain was almost the same. The detection efficiencies were around 0.1% (14MeV) and 0.02% (2.5MeV). These results are consistent with our simulation studies.
D
-brane charges in Gepner models
Authors: Braun Volker , Schäfer-Nameki Sakura
Published: October 2006

We construct Gepner models in terms of coset conformal field theories and compute their twisted equivariant K-theories. These classify the D-brane charges on the associated geometric backgrounds and therefore agree with the topological K-theories. We show this agreement for various cases, in particular, the Fermat quintic.
Thermal characterization of anisotropic media in photothermal point, line, and grating configuration
Authors: Kalogiannakis G. , Van Hemelrijck D. , Longuemart S. , Ravi J. , Okasha A. , Glorieux C.
Published: October 2006

This article is dedicated to the simulation of heat diffusion in layered anisotropic materials. The three-dimensional heat diffusion equation for layered, anisotropic materials is used to calculate a laser induced dynamic temperature distribution, the so-called thermal-wave field, in composites. In the case of isotropic materials, the thermal-wave distribution is always axisymmetric around the center of the heat source. In multilayered fiber reinforced composites, however, the distribution of the thermal-wave field depends on their characteristic stacking sequence as well as on the geometry and the frequency of the source. Together with undergoing experimental work, these theoretical simulations allow us to compare the feasibility of different spatial excitation geometries, namely, point source, line source, and grating source, to determine the thermal conductivity tensor of composite materials. It is proven that the use of a grating suppresses the ill posedness of the inverse problem and simplifies the procedure used for the determination of the thermal properties.
Surface passivation and capping of GaSb photodiode by chemical bath deposition of CdS
Authors: Chavan Ashonita , Chandola Abhinav , Sridaran Sujatha , Dutta Partha
Published: October 2006

A cadmium sulfide thin film deposited by a chemical bath deposition technique has been found to act as a passivating layer and a capping layer for GaSb photodiodes. X-ray photoelectron spectroscopy analysis shows the presence of Ga–S and Sb–S bonds along with the cadmium binding energies. Reduction in the reverse leakage current after the passivation is accompanied by a significant increase in the zero bias resistance-area product (14.29–100Ωcm2). In addition, the dependence of the zero bias resistance-area product on the device dimension reduced considerably. There was no degradation in the dark current performance over a period of 3months, indicating long-term stability.