bluuebunny/crossref_metadata_2025 huggingface dataset:
Can mesoscale models reproduce meandering motions?
Authors: Belušić Danijel , Güttler Ivan
Published: April 2010

The influence of meandering flow on dispersion of pollutants is frequently under‐represented in dispersion models. In terms of measurements, meandering is primarily associated with time‐scales between the turbulence and the applied averaging time, which is usually 1 h. The related spatial scales thus range roughly from 102 to 104 m (referred to here as submesoscales). As the state‐of‐the‐art mesoscale models should be capable of reproducing flow features on scales larger than the turbulence, and as the meandering‐generating mechanisms are not fully understood yet, it is useful to examine if the mesoscale models can reproduce meandering. For that purpose, the WRF/Chem model at 1/3 km horizontal resolution is used to simulate a weak‐wind night during the CASES99 experiment. The measurements are used for detailed model verification. The model with its typical set‐up fails to reproduce the variability at submesoscales and the locus of the under‐representation is traced to too‐strong horizontal diffusion. Reducing or removing the model diffusion allows the appearance of the submeso variability, whose spectral properties and the resulting plume behaviour agree well with the measurements. The linear correlation between the simulations with reproduced variability and the measurements is low, as is the case between two simulations with only slightly different set‐up. The conclusion is that mesoscale models are able to reproduce the strength of variability and the effects of meandering, but only with reduced or removed horizontal diffusion. The question arises whether it is possible to obtain a linear correlation, i.e. to correctly reproduce individual modes at these scales at all. Copyright © 2010 Royal Meteorological Society
Spatial variability of thermal regimes and other environmental determinants of stream fish communities in the Great Lakes Basin, Ontario, Canada
Authors: Chu C. , Jones N. E.
Published: April 2010

Temperature is one of the most important environmental variables in stream ecosystems because it affects the growth, survival and distribution of stream biota. This study examined if the spatial variability of thermal regimes and 18 other environmental variables were associated with fish communities in watersheds throughout the Great Lakes Basin (GLB), Ontario. The thermal regimes were defined as regimes 1, 2 and 3 and had maximum water temperatures of 26.4, 28.4 and 23.5°C, and spring warming rates of 0.20, 0.12 and 0.10 °C d−1, respectively. The spatial variability of the thermal regimes (VTR) within the watersheds was summarized into four VTR groups: S1, S2, M23 and M123. Stream sites in S1 watersheds had temperatures characteristic of regime 1 whereas stream sites in S2 watersheds followed regime 2. M23 watersheds had sites with a mix of regimes 2 and 3 whereas M123 watersheds had all three thermal regimes at sites throughout watersheds. Canonical correspondence analysis (CCA) indicated that 16% of the variation in fish communities was related to the spatial VTR in the watersheds. Forward selection CCA indicated that elevation, the S1 VTR group, sparse forest cover, wetland area, base flow index (groundwater discharge potential), flow and industrial stress explained 42% of the variance in the fish communities. Simplified indicator species analysis (ISA) showed that different species could be used as indicators for each of the VTR groups. Human activities such as industrial development, deforestation, groundwater withdrawal and flow alteration all may affect the environmental variables related to stream fish communities. Copyright © 2010 John Wiley & Sons, Ltd.
The role of intuitive heuristics in students' thinking: Ranking chemical substances
Authors: Maeyer Jenine , Talanquer Vicente
Published: April 2010

The characterization of students' cognitive biases is of central importance in the development of curriculum and teaching strategies that better support student learning in science. In particular, the identification of shortcut reasoning procedures (heuristics) used by students to reduce cognitive load can help us devise strategies to foster the development of more analytical ways of thinking. The central goal of this study was thus to investigate the reasoning heuristics used by undergraduate chemistry students when solving a traditional academic task (ranking chemical substances based on the relative value of a physical or chemical property). For this purpose, a mixed‐methods research study was completed based on quantitative results collected using a ranking‐task questionnaire and qualitative data gathered through semistructured interviews. Our results revealed that many study participants relied frequently on one or more of the following heuristics to make their decisions: recognition, representativeness, one‐reason decision making, and arbitrary trend. These heuristics allowed students to generate answers in the absence of requisite knowledge; unfortunately, they often led students astray. Our results suggest the need to create more opportunities for college chemistry students to monitor their thinking, develop and apply analytical ways of reasoning, and evaluate the effectiveness of shortcut reasoning procedures in different contexts. © 2010 Wiley Periodicals, Inc. Sci Ed 94:963–984, 2010
Tuning the Intensity of Metal‐Enhanced Fluorescence by Engineering Silver Nanoparticle Arrays
Authors: Yang Bingjie , Lu Nan , Qi Dianpeng , Ma Renping , Wu Qiong , Hao Juanyuan , Liu Xiaoming , Mu Ying , Reboud Vincent , Kehagias Nikolaos , Torres Clivia M. Sotomayor , Boey Freddy Yin Chiang , Chen Xiaodong , Chi Lifeng
Published: April 2010

It is demonstrated that silver nanoparticle (SNP) arrays fabricated by combining nanoimprint lithography and electrochemical deposition methods can be used as substrates for metal‐enhanced fluorescence, which is widely used in optics, sensitive detection, and bioimaging. The method presented here is simple and efficient at controlling the nanoparticle density and interparticle distance within one array. Furthermore, it is found that the fluorescence intensity can be tuned by engineering the feature size of the SNP arrays. This is due to the different coupling efficiency between the emission of the fluorophores and surface plasmon resonance band of the metallic nanostructures.
Compensation practices in Central and Eastern European EU member states—an analytical framework based on institutional perspectives, path dependencies, and efficiency considerations
Authors: Festing Marion , Sahakiants Ihar
Published: April 2010

Research on compensation in Central and Eastern European (CEE) countries is scarce, and a comprehensive analysis of factors influencing the adoption and transformation of compensation practices in CEE countries is lacking. This article provides a holistic analytical framework based on a literature review, secondary data on selected compensation practices in CEE countries, and theoretical insights from various perspectives. These include path dependency from the pre‐transformation era; current coercive, mimetic, and normative isomorphic pressures; and efficiency‐based influences on compensation practices. Furthermore, implications are outlined both for future research on compensation management and for human resource management practice in CEE countries. © 2010 Wiley Periodicals, Inc.
Individual pay for performance in Spain: Cognitive sociology and the subsidiary insider perspective
Authors: Drape Thomas G. , Quintanilla Javier , Green Steve G.
Published: April 2010

This article examines how individual pay for performance is interpreted, predominantly by nonmanagerial employees, within the European context, at three subsidiaries of one U.S. multinational corporation in Spain. The study reveals how two levels of the cognitive socialization process color the lens through which employees view pay for performance and reveals how subsidiary founding, politics of resistance, and host‐country effects impact the implementation of the practice. Contrary to past studies in the literature, the study discovered a large number of nonmanagerial employees with a positive interpretation of pay for performance due to the influence of pre‐existing organizational cultural experiences. © 2010 Wiley Periodicals, Inc.
Employee knowledge and the effects of a deferred profit‐sharing system: A longitudinal case study of personnel funds in Finland
Authors: Sweins Christina , Jussila Iiro
Published: April 2010

We explain the special features of the Finnish profit‐sharing system and explore what outcomes this deferred plan has for the company under longitudinal conditions. We measure changes in employee attitudes, effects of the system, and, in particular, the changes in the employee's pay knowledge before and after the combination of a deferred profit‐sharing system with a cash‐based one. Statistical analyses are preceded by qualitative analyses of interview data to provide the reader with an understanding of the context. Even though the employees' pay knowledge has increased and they perceive that they get more feedback on company key ratios, there still is a need for human resource management and managers to provide training and enhance discussions on the pay system for both supervisors and subordinates. © 2010 Wiley Periodicals, Inc.
Reward strategy: Time for a more realistic reconceptualization and reinterpretation?
Authors: Cox Annette , Brown Duncan , Reilly Peter
Published: April 2010

This article focuses on organizations' continued struggles to design and implement successful and credible reward strategies. We argue that a major and neglected factor that accounts for this is how reward strategies are designed and executed with insufficient attention given to employee preferences for different types of reward. We argue that this is both a problem of process in the way reward systems are designed and a problem of how models of reward strategy are built. Developing more effective reward strategies requires a better understanding of holistic rewards and greater attention to line management roles in their implementation. © 2010 Wiley Periodicals, Inc.
The lateral compartmentation of the yeast plasma membrane
Authors: Malinsky Jan , Opekarová Miroslava , Tanner Widmar
Published: April 2010

The plasma membrane of Saccharomyces cerevisiae contains large microdomains enriched in ergosterol, which house at least nine integral proteins, including proton symporters. The domains adopt a characteristic structure of furrow‐like invaginations typically seen in freeze‐fracture pictures of fungal cells. Being stable for the time comparable with the cell cycle duration, they might be considered as fixed islands (rafts) in an otherwise fluid yeast plasma membrane. Rapidly moving endocytic marker proteins avoid the microdomains; the domain‐accumulated proton symporters consequently show a reduced rate of substrate‐induced endocytosis and turnover. Copyright © 2010 John Wiley & Sons, Ltd.
Nicolas Andry de Bois-Regard (Lyon 1658–Paris 1742): The inventor of the word “orthopaedics” and the father of parasitology
Authors: Kohler Remi
Published: April 2010

This is an historical essay about Nicolas Andry, a French medical doctor (Lyon 1658–Paris 1742) who wrote in 1741 the famous book called “L'orthopedie”, which was soon after translated into English (1742) “Orthopaedia or the art of correcting and preventing deformities in children”. His life and works are detailed as the containment of the book composed of two volumes and many engravings (the crooked tree has become the symbol of numerous orthopaedic societies around the world). A discussion of semantics (ORTHO-PEDIE) and evolution of the meaning of this word is also discussed.
Gene expression profiling of suicide completers
Authors: Fiori L.M. , Turecki G.
Published: April 2010

Despite strong evidence for a role of biological factors in the etiology and pathology of suicide, the study of traditional neurotransmitter systems has been able to explain only a small proportion of the neurobiology of what is now recognized as a complex genetic trait. The use of microarrays to simultaneously examine the expression levels of thousands of gene transcripts has vastly expanded our capacity to detect the involvement of additional genes and pathways in suicidality, and has opened many new avenues for the discovery of the biological underpinnings of suicide completion. This review examines microarray studies which have been used to identify genes displaying altered expression in suicide completers, and highlights some of the important methodological considerations and metabolic pathways which have emerged from these analyses.
The genetics of neurosystems in mental ill-health and suicidality: Beyond serotonin
Authors: Rujescu D. , Giegling I.
Published: April 2010

Suicidal behavior is a major health problem worldwide. The risk of suicide-related behavior is supposed to be determined by a complex interplay of sociocultural factors, psychiatric history, personality traits, and genetic vulnerability. Family and twin studies point towards a partial heritability of suicidal behavior. First molecular genetic studies concentrated on genes of the serotonergic system based on the biochemical evidence that serotonergic neurotransmission is implicated in this behavior. Furthermore, genes of e.g. the dopaminergic and noradrenergic neurotransmitter systems have also been the subject of investigations in this context. The aim of this article is to review molecular genetic studies in suicidal behavior beyond the serotonergic system and to emphasize findings on new genes.
Arf GAPs: Gatekeepers of vesicle generation
Authors: Spang Anne , Shiba Yoko , Randazzo Paul A.
Published: April 2010

Arf GAP proteins are a versatile and diverse group of proteins. They control the activity of the GTP‐binding proteins of the ARF family by inducing the hydrolysis of GTP that is bound to Arf proteins. The best‐studied role of Arf GAPs is in intracellular traffic. In this review, we will focus mainly on the Arf GAPs that play a role in vesicle formation, Arf GAP1, Arf GAP2 and Arf GAP3 and their yeast homologues, Gcs1p and Glo3p. We discuss the roles of Arf GAPs as regulators and effectors for Arf GTP‐binding proteins.
Helminth parasites of the Kafue lechwe antelope (Kobus leche kafuensis): a potential source of infection to domestic animals in the Kafue wetlands of Zambia
Authors: Phiri A.M. , Chota A. , Muma J.B. , Munyeme M. , Sikasunge C.S.
Published: April 2010

The Kafue lechwe antelope (Kobus leche kafuensis), a medium-sized, semi-aquatic antelope, grazes extensively on pastures accessed by livestock in and around Lochinvar and Blue Lagoon national parks in the Kafue wetlands of Zambia. This interaction has a potential for bi-modal transmission of a wide range of parasitic helminths between lechwe and domestic ruminants. A survey was conducted to investigate the status of helminths in the Kafue lechwe during the 2008 (July–December) hunting season, involving 65 animals hunted under special research licences. Worm identification was based on morphological features using standard identification keys. Eleven different types of helminths were identified in the animals studied; namely, Oesophagostomum, Bunostomum, Cooperia, Dictyocaulus, Marshallagia, Stilesia, Setaria, Trichuris, Fasciola, amphistomes and Schistosoma. Amphistomes (100%) and Oesophagostomum (60.9%) were the most common while Fasciola (7.8%) and Stilesia (1.6%) were the least of the identified helminths. There was no evidence that helminths, at intensities observed, adversely affected the health of the lechwe. The degree of worm infection was observed to vary between the two study areas, with Blue Lagoon recording higher infection levels compared to Lochinvar. The host range of many of the helminths found in the Kafue lechwe is broad and could serve as a potentially stable source of infection to domestic animals such as goats and cattle. Therefore, issues concerning livestock management and conservation may arise.
Sinonasal inverted papilloma: narrative review
Authors: Anari S , Carrie S
Published: April 2010

Background:

Sinonasal inverted papilloma is a benign condition with the potential for recurrence and malignant change. Over the past few decades, numerous studies and reviews have addressed different aspects of this condition.

Objective:

To amalgamate the current literature on inverted papilloma, in order to review the evidence and consider the gaps in current knowledge.

Methods:

Retrospective, narrative review.

Results:

The reported incidence of inverted papilloma varies between centres and is affected by selection bias. The exact aetiology of inverted papilloma is not fully understood. Currently, there is no reliable histological or biological marker to predict the probability of recurrence or malignant transformation. There is no universally accepted staging system available for sinonasal inverted papilloma. Complete surgical removal of the tumour is the mainstay of treatment, but the method of choice depends on the extent of the disease, the skill of the surgeon and the technology available.

Conclusion:

In order to compare different studies and to enable meta-analysis of the literature, there should be a universally accepted staging and classification system for sinonasal inverted papilloma. Further research on the aetiology of sinonasal inverted papilloma, and on biological markers for its recurrence and malignant transformation, is required. To enable meaningful future research, we would encourage multicentre participation with a consensus on management.
Inflation of Foley catheters for postnasal packing
Authors: Rashid M , Karagama Y
Published: April 2010

Background:

Foley catheters are commonly used to control posterior epistaxis in most ENT departments. There are very few studies of the ideal substance for inflating Foley catheters for posterior epistaxis. This in vitro study compared the effects of water, saline and air in delivering effective tamponade.

Methods:

Three groups of five Foley catheters each were filled with 10 ml of water, saline or air. Forty-eight hours later, the residual volume was aspirated and measured.

Results:

At 48 hours, the following residual volumes were aspirated: air, 0 ml; saline, 8.5 ml; and water, 8.7 ml.

Conclusion:

This study shows that air is not suitable for inflating Foley catheters, as they had spontaneously deflated when assessed 48 hours after inflation. We hypothesise that water is a better Foley catheter inflation fluid than saline. We recommend a larger, in vivo study to ascertain the benefits of these Foley catheter inflation substances in curtailing epistaxis in the clinical setting.
Use of posaconazole in the treatment of infective rhinocerebral mucormycosis
Authors: Kulendra K , Habibi M , Butler C , Clarke P , Howard D
Published: April 2010

Introduction:

A patients with undiagnosed type II diabetes mellitus presented with infective rhinocerebral mucormycosis.

Investigation results:

Initial magnetic resonance imaging scans demonstrated an aggressive disease process involving the left orbit and paranasal sinuses. A repeated scan following treatment excluded intracranial spread or recurrence. Pus from the paranasal sinuses grew Rhizopus arrhizus on microbiological culture.

Management:

Initial treatment comprised intravenous liposomal amphotericin B, intravenous co-amoxiclav and surgical debridement. The patient's diabetes was managed medically. The development of drug-induced transaminitis required a change of medication. The dose of liposomal amphotericin B was reduced, and then titrated back up as the liver function test results improved. Posaconazole was also introduced and the patient was eventually discharged on this alone, as the maximum recommended cumulative dose of liposomal amphotericin B had been reached.

Conclusions:

Posaconazole may be used effectively in conjunction with surgical debridement in the treatment of patients with infective rhinocerebral mucormycosis who develop hepatotoxic side effects to liposomal amphotericin B. Posaconazole may also allow a reduction in the dose of liposomal amphotericin B, resulting in better tolerance.
Carbon monoxide poisoning: an unusual cause of dizziness
Authors: Lakhani R , Bleach N
Published: April 2010

Objective:

We report an unusual case of dizziness caused by carbon monoxide poisoning.

Case report:

A 55-year-old man was referred to an ENT surgeon with dizziness. The patient described vague, non-specific symptoms not consistent with a diagnosis of benign paroxysmal positional vertigo, labyrinthitis or Ménière's disease. It emerged later that the patient had been suffering from carbon monoxide poisoning from a leaky gas hot water boiler in his house. After having the boiler fixed, the patient's symptoms completely resolved.

Conclusion:

When the more common causes of dizziness cannot be found, less common but important differential diagnoses, such as carbon monoxide poisoning, should be considered.
Der-p2 (Dermatophagoides pteronyssinus) allergen-like protein from the hard tickIxodes ricinus– a novel member of ML (MD-2-related lipid-recognition) domain protein family
Authors: HORÁČKOVÁ J. , RUDENKO N. , GOLOVCHENKO M. , GRUBHOFFER L.
Published: April 2010

Objective.Expression of the gene encoding Der-p2 allergen-like protein in the castor bean tickIxodes ricinusis induced by blood intake. Tick Der-p2 allergen-like protein belongs to a diverse family of ML proteins that includes major allergens of house dust mites, human MD-2 or similar proteins fromDrosophila melanogaster. In ticks, genes encoding proteins belonging to the ML protein family were identified, but their protein products have not been characterized yet.Methods.A gene encoding tick Der-p2 allergen-like protein was amplified from cDNA of engorgedI. ricinusfemale using the gene-specific primers designed on a basis of partial sequences of related allergen-like genes. The tissue and state specific patterns of expression of the gene were analysed. The IgE binding activity of the produced recombinant protein was studied by use of ELISA.Results.Analysis of the expression pattern showed that the gene encoding the tick Der-p2 allergen-like protein is strongly induced by the bloodmeal in gut and haemolymph throughout all tick developmental stages. Der-p2 allergen-like protein possesses a putative lipid-binding site, according to the comparisons with the related proteins. The ability of tick Der-p2 allergen-like protein to bind immunoglobulin E (IgE) was revealed.Discussion.The presence of a putative lipid-binding domain in Der-p2 allergen-like protein and its ability to interact with IgE might indicate the involvement of the protein in the tick's immune response.
Prediction of prevalence from mean abundance via a simple epidemiological model in mesostigmate mites from two geographical regions
Authors: KRASNOV B. R. , KORALLO-VINARSKAYA N. P. , VINARSKI M. V. , LARESCHI M.
Published: April 2010

We analysed data on the abundance and distribution of 26 species of mesostigmate mites with different feeding habits collected from bodies of small mammalian hosts in 2 geographical regions (West Siberia and Argentina). We tested whether prevalence of a mite can be reliably predicted from a simple epidemiological model that takes into account mean abundance and its variance. We theorized that the difference between prevalence predicted from the model and observed prevalence would be smallest in obligatory haematophagous mites, intermediate in facultatively haematophagous mites and greatest in non-haematophagous mites. We also theorized that prevalence of mites from the region with sharp seasonality (Siberia) would be predicted accurately only if host number would be taken into account. We found that the success of a simple epidemiological model to predict prevalence in mites was similar to that reported earlier for other ectoparasitic arthropods. Surprisingly, the model predicted prevalence of obligatory exclusively haematophagous mites less successfully than that of mites with other feeding habits. No difference in the model performance between mites occurring in the 2 geographical regions were found independent of whether the model took the number of hosts into account.
Proteomic analysis of Strongyloides stercoralis L3 larvae
Authors: MARCILLA A. , SOTILLO J. , PÉREZ-GARCIA A. , IGUAL-ADELL R. , VALERO M. LUZ , SÁNCHEZ-PINO M. M. , BERNAL D. , MUÑOZ-ANTOLÍ C. , TRELIS M. , TOLEDO R. , ESTEBAN J. G.
Published: April 2010

Strongyloidiasis can be perpetuated by autoinfection with the filariform larvae L3, causing asymptomatic chronic infections and creating a population of carriers, affecting not only developing countries. So far, very little is known about the proteins that interact with the human host, and few proteins from the infective Strongyloides stercoralis L3 have been characterized. Here, we report results obtained from a proteomic analysis of the proteins from S. stercoralis L3 larvae obtained from patients. Since the genome of S. stercoralis is not yet available, we used proteomic analysis to identify 26 different proteins, 13 of them released by short digestion with trypsin, which could represent surface-associated proteins. The present work extends our knowledge of host-parasite interactions by identifying proteins that could be of interest in the development of diagnostic tools, vaccines, or treatments for a neglected disease like strongyloidiasis.
Influence of beam intensity profile on the aerodynamic particle size distributions generated by femtosecond laser ablation
Authors: Menéndez-Manjón A. , Barcikowski S. , Shafeev G.A. , Mazhukin V.I. , Chichkov B.N.
Published: April 2010

The dependence of nanoparticle size distributions on laser intensity profile was determined during infrared femtosecond laser ablation of silver targets in air. Laser parameters were adjusted to ablate at the same peak fluence with spatially homogeneous (flat-top) and inhomogeneous (Gaussian) intensity distributions formed by diffractive optical elements. Aerodynamic particle size was measured online by an electric low-pressure cascade impactor. Narrower size distributions were detected for the flat-top intensity profile in the fluence range from 0.6 to 4.4 J/cm2, while the Gaussian beam produced broad and bimodal distributions. The aerodynamic number frequency of the primary nanoparticulate fraction (40 nm) was equal to the number frequency of the submicron agglomerate fraction (200 nm) at laser fluence of 1 J/cm2. The Feret diameter of primary particles was 80 nm. Geometrical interpretation of the irradiated spots at the corresponding laser fluence regimes explains the formation of bimodal (submicron and nanoparticulate) size distribution in the case of Gaussian beams. The bimodality is attributed to different thermalization pathways during laser ablation.
Effect of magnetic field on the expansion dynamics of laser-blow-off generated plasma plume: Role of atomic processes
Authors: Kumar Ajai , Singh R.K. , Prahlad V. , Joshi H.C.
Published: April 2010

The effect of a variable magnetic field on Li plasma produced by laser-blow-off technique has been studied experimentally. Enhancement in the intensity of the spectral lines from neutrals was observed, which varied with the magnetic field. The enhancement in emission from Li I was found to differ for the two different transitions viz. 670.8 nm (2s 2S1/2 ← 2p 2P3/2,1/2) and 610.3 nm (2p 2P1/2,3/2 ← 3d 2P3/2,5/2), which is more prominent for 670.8 nm. Conventionally, the enhancement in emission in the presence of the magnetic field has been explained in terms of radiative recombination. However, the atomic analysis by computing photon emissivity coefficients in the present case has revealed for the first time that it is due to electron impact excitation.
Improved two-temperature model and its application in femtosecond laser ablation of metal target
Authors: Fang Ranran , Zhang Duanming , Wei Hua , Li Zhihua , Yang Fengxia , Gao Yihua
Published: April 2010

An improved two-temperature model to describe femtosecond laser ablation of metal target was presented. The temperature-dependent heat capacity and thermal conductivity of the electron, as well as electron temperature-dependent absorption coefficient and absorptivity are all considered in this two-temperature model. The tailored two-temperature model is solved using a finite difference method for copper target. The time-dependence of lattice and electron temperature of the surface for different laser fluence are performed, respectively. The temperature distribution of the electron and lattice along with space and time for a certain laser fluence is also presented. Moreover, the variation of ablation rate per pulse with laser fluence is obtained. The satisfactory agreement between our numerical results and experimental data indicates that the temperature dependence of heat capacity, thermal conductivity, absorption coefficient and absorptivity in femtosecond laser ablation of metal target must not be neglected. The present model will be helpful for the further experimental investigation of application of the femtosecond laser.
Measurement of stimulated Brillouin scattering threshold by the optical limiting of pump output energy
Authors: Gao W. , Lu Z.W. , Wang S.Y. , He W.M. , Hasi W.L.J.
Published: April 2010

A new approach to measure stimulated Brillouin scattering threshold based on the output energy characteristic of stimulated Brillouin scattering optical limiting is proposed. The stimulated Brillouin scattering threshold or its exponential gain, Gth, can be accurately and conveniently determined by the intersection point of linear-fitting lines of the output energy below and above the threshold. The values of Gth in CS2 and FC-72 for different wavelengths and interaction lengths are measured in Continuum's Nd:YAG Q-switched laser and its frequency-doubled system. We show that Gth for transient regime is larger than that for steady state, and increases with the pump wavelength and the interaction length.
Field distribution, HPM multipactor, and plasma discharge on the periodic triangular surface
Authors: Chang C. , Liu G.Z. , Fang J.Y. , Tang C.X. , Huang H.J. , Chen C.H. , Zhang Q.Y. , Liang T.Z. , Zhu X.X. , Li J.W.
Published: April 2010

The field distribution and the restraint effect of multipactor and plasma discharge on the periodic triangular surface have been theoretically and experimentally analyzed. It has been found by computational and simulative analysis that the periodic profile can quickly restrain or weaken multipactor and plasma discharge in low pressure within several microwave periods. Considering the field enhancement, increasing the slope angle, advancing the electric field, and lowering the frequency can enhance the multipactor suppression. X-band giga-watt high power microwave experiment with 20 ns short pulse was conducted. It was demonstrated that the periodic profile can effectively improve the breakdown threshold and slower the speed of tail erosion.
Acceleration of electrons and electromagnetic fields of highly intense laser pulses
Authors: Lourenco Stefanie , Kowarsch Nicolas , Scheid Werner , Wang P.X.
Published: April 2010

The acceleration of electrons by very intense lasers in vacuum is studied for different forms of laser pulses: finite plane and three-dimensional laser pulses. The latter case is treated by introducing an approximation of the laser frequency as a function of the Cartesian components of the wave number. Various examples which lead to high accelerations of electrons are given.
Funnel cone for focusing intense ion beams on a target
Authors: Bieniosek F.M. , Henestroza E. , Ni P.
Published: April 2010

We describe a funnel cone for concentrating an ion beam on a target. The cone utilizes the reflection characteristic of ion beams on solid walls to focus the incident beam and increase beam intensity on target. The cone has been modeled with the TRIM code. A prototype has been tested and installed for use in the 350-keV K+ NDCX target chamber.
Efficient ion acceleration by collective laser-driven electron dynamics with ultra-thin foil targets
Authors: Steinke S. , Henig A. , Schnürer M. , Sokollik T. , Nickles P.V. , Jung D. , Kiefer D. , Hörlein R. , Schreiber J. , Tajima T. , Yan X.Q. , Hegelich M. , Meyer-ter-Vehn J. , Sandner W. , Habs D.
Published: April 2010

Experiments on ion acceleration by irradiation of ultra-thin diamond-like carbon (DLC) foils, with thicknesses well below the skin depth, irradiated with laser pulses of ultra-high contrast and linear polarization, are presented. A maximum energy of 13 MeV for protons and 71 MeV for carbon ions is observed with a conversion efficiency of ~10%. Two-dimensional particle-in-cell (PIC) simulations reveal that the increase in ion energies can be attributed to a dominantly collective rather than thermal motion of the foil electrons, when the target becomes transparent for the incident laser pulse.
Between Reconstructions: Congressional Action on Civil Rights, 1891–1940
Authors: Jenkins Jeffery A. , Peck Justin , Weaver Vesla M.
Published: April 2010

Prior analyses of congressional action on the issue of black civil rights have typically examined either of the two major Reconstructions. Our paper attempts to fill the large five-decade black box between the end of the First Reconstruction and the beginning of the Second, routinely skipped over in scholarship on Congress, parties, and racial politics. Using a variety of sources—bill-introduction data, statements by members in theCongressional Record, roll-call votes, and newspaper reports, among others—we challenge the common assumption that civil rights largely disappeared from the congressional agenda between 1891 and 1940, documenting instead the continued contestation over racial issues in Congress. By examining several failed anti-lynching initiatives, this article uncovers a largely untold story about how and when the Republican and Democratic Parties reorganized around race, finding that the realignment began earlier than is commonly understood.
The role of porcine reproductive and respiratory syndrome (PRRS) virus structural and non-structural proteins in virus pathogenesis
Authors: Music Nedzad , Gagnon Carl A.
Published: April 2010

Porcine reproductive and respiratory syndrome (PRRS) is an economically devastating viral disease affecting the swine industry worldwide. The etiological agent, PRRS virus (PRRSV), possesses a RNA viral genome with nine open reading frames (ORFs). The ORF1a and ORF1b replicase-associated genes encode the polyproteins pp1a and pp1ab, respectively. The pp1a is processed in nine non-structural proteins (nsps): nsp1α, nsp1β, and nsp2 to nsp8. Proteolytic cleavage of pp1ab generates products nsp9 to nsp12. The proteolytic pp1a cleavage products process and cleave pp1a and pp1ab into nsp products. The nsp9 to nsp12 are involved in virus genome transcription and replication. The 3′ end of the viral genome encodes four minor and three major structural proteins. The GP2a, GP3and GP4(encoded by ORF2a, 3 and 4), are glycosylated membrane associated minor structural proteins. The fourth minor structural protein, the E protein (encoded by ORF2b), is an unglycosylated membrane associated protein. The viral envelope contains two major structural proteins: a glycosylated major envelope protein GP5(encoded by ORF5) and an unglycosylated membrane M protein (encoded by ORF6). The third major structural protein is the nucleocapsid N protein (encoded by ORF7). All PRRSV non-structural and structural proteins are essential for virus replication, and PRRSV infectivity is relatively intolerant to subtle changes within the structural proteins. PRRSV virulence is multigenic and resides in both the non-structural and structural viral proteins. This review discusses the molecular characteristics, biological and immunological functions of the PRRSV structural and nsps and their involvement in the virus pathogenesis.
Motives of Azumaya algebras
Authors: Kahn Bruno , Levine Marc
Published: April 2010

We study the slice filtration for theK-theory of a sheaf of Azumaya algebrasA, and for the motive of a Severi-Brauer variety, the latter in the case of a central simple algebra of prime degree over a field. Using the Beilinson–Lichtenbaum conjecture, we apply our results to show the vanishing ofSK2(A) for a central simple algebraAof square-free index (prime to the characteristic). This proves a conjecture of Merkurjev.
The specific role of histone deacetylase 2 in adult neurogenesis
Authors: Jawerka Melanie , Colak Dilek , Dimou Leda , Spiller Carmen , Lagger Sabine , Montgomery Rusty L. , Olson Eric N. , Wurst Wolfgang , Göttlicher Martin , Götz Magdalena
Published: April 2010

Gene expression changes during cell differentiation are thought to be coordinated by histone modifications, but still little is known about the role of specific histone deacetylases (HDACs) in cell fate decisionsin vivo. Here we demonstrate that the catalytic function of HDAC2 is required in adult, but not embryonic neurogenesis. While brain development and adult stem cell fate were normal upon conditional deletion of HDAC2 or in mice lacking the catalytic activity of HDAC2, neurons derived from both zones of adult neurogenesis die at a specific maturation stage. This phenotype is correlated with an increase in proliferation and the aberrant maintenance of proteins normally expressed only in progenitors, such as Sox2, also into some differentiating neurons, suggesting that HDAC2 is critically required to silence progenitor transcripts during neuronal differentiation of adult generated neurons. This cell-autonomous function of HDAC2 exclusively in adult neurogenesis reveals clear differences in the molecular mechanisms regulating neurogenesis during development and in adulthood.
Sexualmedizinische Behandlungsfälle – Entwicklungen 1980 – 1990 – 2004
Authors: Sigg  , Klaghofer  , Imthurn  , Buddeberg
Published: April 2010

Sexuelle Funktionsstörungen können die Lebenszufriedenheit von Frauen und Männern nachhaltig beeinträchtigen. Neben sexualmedizinischen Angeboten in der ärztlichen Grundversorgung existieren in der Schweiz an Universitätsspitälern Spezialsprechstunden. Die Auswertung von Krankengeschichten von drei Jahrgangskohorten (1980, 1990, 2004) der Sexualmedizinischen Sprechstunde am Universitätsspital Zürich ergab u.a. folgende Ergebnisse: Bei Frauen sind Libidomangel bzw. -verlust und bei Männern erektile Dysfunktion die häufigsten Störungen. In den letzten Jahren sind die Behandlungsmöglichkeiten sexueller Störungen differenzierter geworden. Zwischen den zuweisenden Ärzten und den sexualmedizinischen Spezialisten hat sich die Zusammenarbeit zwischen 1980 und 2004 merklich verbessert. Nach Abklärung und Primärbehandlung in der Spezialsprechstunde werden viele Patienten zur Weiterbehandlung an die zuweisenden Ärzte zurück überwiesen. Die sexualmedizinische Aus- und Fortbildung sollte weiter intensiviert und verbessert werden.
Multimodale Therapie funktioneller Erkrankungen des Verdauungstraktes
Authors: Egloff  , Beer  , Gschossmann  , Sendensky  , Känel von
Published: April 2010

Funktionelle Störungen des Gastrointestinaltrakts, wie das Reizdarmsyndrom und die funktionelle Dyspepsie, erfordern einen multimodalen Therapieansatz. Entsprechend der multikausalen Pathogenese kommen – neben medikamentösen Therapien – ernährungsspezifische, relaxationsfördernde, verhaltenstherapeutische und psychoedukative Massnahmen hinzu. Diese müssen dem Schweregrad des Leidens und dem individuellen Patientenprofil angepasst werden. Ausgangspunkt jeder Therapie und Basis für eine gute Compliance ist die sorgfältige Information und Aufklärung des Patienten. In diesem Artikel werden die Therapieelemente aus interdisziplinärer Sicht aufgezeigt.
Œdème pulmonaire chez un jeune homme sportif
Authors: Regamey  , Méan  , Scherrer
Published: April 2010

Cet article rapporte le cas d'un homme de 31 ans présentant un Œdème pulmonaire au décours d'un laryngospasme après extubation. Cette pathologie, mieux connue des anesthésistes, résulte en premier lieu d'une augmentation rapide de la pression négative intrapleurale. Elle n'est classiquement pas associée à des co-morbidités cardio-vasculaires. L'évolution est indolente avec résolution dans les 48h sous oxygénothérapie et ventilation à pression positive expiratoire.
Anthropogenic carbon accumulation in the subtropical North Atlantic
Authors: Brown Peter J. , Bakker Dorothee C. E. , Schuster Ute , Watson Andrew J.
Published: April 2010

Recent data suggest the accumulation of anthropogenic carbon dioxide (ΔCanth) in the subtropical North Atlantic is not occurring at a steady rate throughout the water column. Carbon measurements from three transatlantic cruises along 24.5°N in 1992, 1998, and 2004 were investigated for changes in Canth using both a back‐calculation shortcut technique and extended multiple linear regression. For three time periods (1992–1998, 1998–2004, and 1992–2004) we observed spatial and vertical changes in Canth storage, along with a general increase in total concentration. In the surface layers, total dissolved inorganic carbon (TCO2) and Canth concentrations increased in line with atmospheric CO2 levels: TCO2 +8.8 ± 0.5 μmol kg−1 for 1992–1998 and +8.6 ± 0.5 μmol kg−1 for 1998–2004 and Canth +8.0 ± 0.2 μmol kg−1 for 1992–1998 and +6.8 ± 0.3 μmol kg−1 for 1998–2004. In deeper waters, ΔCanth was significantly different than zero for all depths above 5000 dbar between 1992 and 2004, while on a subdecadal timescale, significant variability was observed for ΔCanth at a depth range of 800–1000 dbar. Evidence is presented for the arrival at 24.5°N at depth of freshly ventilated Labrador Sea Water from the subpolar North Atlantic between 1992 and 1998, as well as consistent smaller ΔCanth signals alongside the Mid‐Atlantic Ridge. This is in addition to low‐level, stable increases identified in the deep eastern basin between 1992 and 2004, the first time that ΔCanth has been detected and confirmed by new measurements of carbon tetrachloride and CFC‐11 from 2004. These results highlight the importance of the subtropics as a site for long‐term Canth storage away from the surface.
Hybrid simulation of mode conversion at the magnetopause
Authors: Lin Y. , Johnson J. R. , Wang X. Y.
Published: April 2010

Two‐dimensional hybrid simulations are used to investigate how fast‐mode compressional waves incident on a magnetopause current layer mode convert both linearly and nonlinearly to short wavelength (k⊥ρi ∼ 1) kinetic Alfvén waves near the Alfvén resonance surface. The background magnetic fields on both sides of the current layer are parallel to each other and perpendicular to the magnetopause normal, corresponding to a northward interplanetary magnetic field. The simulations are performed in a 2‐D plane (xz), where x is normal to the magnetopause and z is tilted by an angle, θ, relative to the magnetic field. We examine how the mode conversion depends on wave frequency ω0, wave vector, Alfvén velocity profile (particularly the magnetopause width, D0), ion β in the magnetosheath, electron‐to‐ion temperature ratio, and incident wave amplitude. Kinetic effects resolve the resonance, and KAWs radiate back to the magnetosheath side of the current layer. The compressional wave absorption rate is estimated and compared with linear theory. Unlike the prediction from low‐frequency theory of the Alfvén resonance, KAWs are also generated in cases with θ = 0°, provided ω0 > 0.1Ω0, with Ω0 being the ion cyclotron frequency in the magnetosheath. As the incident wave amplitude is increased, several nonlinear wave properties are manifested in the mode conversion process. Harmonics of the driver frequency are generated. As a result of nonlinear wave interaction, the mode conversion region and its spectral width are broadened. The nonlinear waves provide a significant transport of momentum across the magnetopause and are associated with significant ion heating in the resonant region.
SKS and SPdKS sensitivity to two‐dimensional ultralow‐velocity zones
Authors: Rondenay Stéphane , Cormier Vernon F. , Van Ark Emily M.
Published: April 2010

Seismic wave propagation through two‐dimensional core‐mantle boundary (CMB) ultralow‐velocity zones (ULVZs) is modeled using a global pseudospectral algorithm. Seismograms are synthesized for several types of ULVZ models to investigate the effect of these structures on SKS and SPdKS phases. One‐dimensional models and two‐dimensional models with different, quasi‐1‐D velocity structures on the source and receiver sides of the CMB provide a baseline for comparison with other 2‐D models. Models with finite length ULVZs are used to test the sensitivity of the SPdKS travel time and waveform to different portions of the P diffracted wave path. This test shows that SPdKS waves are only sensitive to ULVZs with lengths >100 km. Our results give three tools for identifying and characterizing 2‐D ULVZ structures. First, dual SPdKS pulses indicate exposure to at least two separate CMB velocity structures, either different source and receiver‐side CMB velocities or different adjacent velocity regions for which Pdiff inception occurs outside of and propagates into a ULVZ. Second, high‐amplitude SKS precursors indicate a very “strong” (i.e., thick and/or large velocity perturbations) ULVZ. Hence, the absence of SKS precursors in most previous ULVZ studies indicates that very strong, sharp ULVZs are not common. Third, mean SPdKS delays relative to PREM constrain the minimum ULVZ strength and length combinations required to produce a given travel time delay.
The MOPITT version 4 CO product: Algorithm enhancements, validation, and long‐term stability
Authors: Deeter M. N. , Edwards D. P. , Gille J. C. , Emmons L. K. , Francis G. , Ho S.‐P. , Mao D. , Masters D. , Worden H. , Drummond James R. , Novelli Paul C.
Published: April 2010

Vertical profiles of carbon monoxide (CO) concentration and corresponding total column values derived from measurements made by the Measurements of Pollution in the Troposphere (MOPITT) satellite instrument are now being processed operationally with the “version 4” (V4) retrieval algorithm. This algorithm exploits the results of analyses of in situ data, chemical transport modeling, and radiative transfer modeling in the MOPITT postlaunch era. Improvements in the V4 product are evident in both clean and polluted conditions. The new products are validated using CO in situ measurements acquired from aircraft from 2000 to 2007. As determined by both retrieval simulations and observations, retrieval bias drift is typically about 1 ppbv/yr for levels in the middle troposphere and about 2 ppbv/yr in the upper troposphere. Retrieval simulations indicate that observed bias drift may be the result of gradual on‐orbit changes in the instrument's modulation cell parameters.