bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Two Land Surface Schemes Used in Terrains of Increasing Aridity in West Africa
Authors: Schüttemeyer D. , Moene A. F. , Holtslag A. A. M. , de Bruin H. A. R.
Published: April 2008

In this study different parameterizations for land surface models currently employed in meteorological models at ECMWF [Tiled ECMWF Surface Scheme for Exchange Processes over Land (TESSEL)] and NCEP (Noah) are evaluated for a semiarid region in Ghana, West Africa. Both schemes utilize the Jarvis–Stewart approach to calculate canopy conductance as the critical variable for partitioning the available energy into sensible and latent heat flux. Additionally, an approach within Noah is tested to calculate canopy conductance based on plant physiology (A-gs method), where the photosynthetic assimilation is coupled to the leaf stomatal conductance.

All parameterizations were run offline for a seasonal cycle in 2002/03 using observations as forcings at two test sites. The two locations are in the humid tropical southern region and in the drier northern region. For the purpose of forcing and evaluation, a new set of data has been utilized to include surface fluxes obtained by scintillometry. The measurements include the rapid wet-to-dry transition after the wet season at both sites.

As a general trend, it has been found that during the wet period of a season net radiation is described well by all parameterizations. During the drying process the errors in modeled net radiation increased at both sites. The models perform poorly in simulating soil heat fluxes with larger errors for TESSEL for both sites. The evolution in time for sensible heat flux and latent heat flux was tackled in different ways by the utilized parameterizations and sites with enhanced model performance for the more southern site. Soil moisture in the upper soil layers is modeled with small errors for the different parameterizations.

Key adjustments for reducing net radiation during the dry period of a season are discussed. In particular, the ratio of roughness length of momentum and heat was found to be an important parameter, but will require seasonal adjustments.
Evaluating Uncertainties in the Projection of Future Drought
Authors: Burke Eleanor J. , Brown Simon J.
Published: April 2008

The uncertainty in the projection of future drought occurrence was explored for four different drought indices using two model ensembles. The first ensemble expresses uncertainty in the parameter space of the third Hadley Centre climate model, and the second is a multimodel ensemble that additionally expresses structural uncertainty in the climate modeling process. The standardized precipitation index (SPI), the precipitation and potential evaporation anomaly (PPEA), the Palmer drought severity index (PDSI), and the soil moisture anomaly (SMA) were derived for both a single CO2 (1×CO2) and a double CO2 (2×CO2) climate. The change in moderate drought, defined by the 20th percentile of the relevant 1×CO2 distribution, was calculated. SPI, based solely on precipitation, shows little change in the proportion of the land surface in drought. All the other indices, which include a measure of the atmospheric demand for moisture, show a significant increase with an additional 5%–45% of the land surface in drought. There are large uncertainties in regional changes in drought. Regions where the precipitation decreases show a reproducible increase in drought across ensemble members and indices. In other regions the sign and magnitude of the change in drought is dependent on index definition and ensemble member, suggesting that the selection of appropriate drought indices is important for impact studies.
Bursting-Layer Modeling Based on the Assumption of the Averaged Sea Surface for Strong Wind-Driven Currents
Authors: Murakami Tomokazu , Yasuda Takashi
Published: April 2008

In the sea, which is affected by strong winds that cover the water surface with wind-wave breakers, the sea surface layer, called the bursting layer by authors, is generated immediately below the mean water level. For treatment of strong wind-driven currents, it is necessary to model the bursting layer correctly based on observed data. However, an essential difficulty occurs in that, because of large water surface displacement caused by developed wind waves, water particle velocities above the wave trough level cannot be measured continuously in the Eulerian coordinates when measuring the velocity of strong wind-driven currents. Consequently, it is impossible to apply the Reynolds average rule to the velocity field above the wave trough level.

In this study, an experiment that uses a wind-wave tank with a double bottom is performed to measure the horizontal velocity of currents driven only by the wind stress. The vertical distribution up to the mean water level is determined to make its vertically integrated value agree with the total mass flux of the wind-driven currents. Furthermore, the vertical distribution of the Reynolds stress is derived by solving a Reynolds equation; its solution agrees with the given velocity distribution. Numerical simulation was performed to reproduce the strong wind-driven currents. Results showed that the bursting-layer model can correctly calculate the steep vertical distribution of the current velocity in the bursting layer.
Wave-Coherent Air–Sea Heat Flux
Authors: Veron Fabrice , Melville W. Kendall , Lenain Luc
Published: April 2008

Air–sea fluxes of heat and momentum play a crucial role in weather, climate, and the coupled general circulation of the oceans and atmosphere. Much progress has been made to quantify momentum transfer from the atmosphere to the ocean for a wide range of wind and wave conditions. Yet, despite the fact that global heat budgets are now at the forefront of current research in atmospheric, oceanographic, and climate problems and despite the good research progress in recent years, much remains to be done to better understand and quantify air–sea heat transfer. It is well known that ocean-surface waves may support momentum transfer from the atmosphere to the ocean, but the role of the waves in heat transfer has been ambiguous and poorly understood. Here, evidence is presented that there are surface wave–coherent components of both the sensible and the latent heat fluxes. Presented here are data from three field experiments that show modulations of temperature and humidity at the surface and at 10–14 m above the surface, which are coherent with the surface wave field. The authors show that the phase relationship between temperature and surface displacement is a function of wind speed. At a 10–12-m elevation, a wave-coherent heat transfer of O(1) W m−2 is found, dominated by the latent heat transfer, as well as wave-coherent fractional contributions to the total heat flux (the sum of latent and sensible heat fluxes) of up to 7%. For the wind speeds and wave conditions of these experiments, which encompass the range of global averages, this wave contribution to total heat flux is comparable in magnitude to the atmospheric heat fluxes commonly attributed to the effects of greenhouse gases or aerosols. By analogy with momentum transfer, the authors expect the wave-coherent heat transfer to decay with height over scales on the order of k−1, where k is the characteristic surface wavenumber; therefore, it is also expected that measurements at elevations of O(10) m may underestimate the contribution of the wave-induced heat flux to the atmosphere.
Orographic Clouds in Terrain-Blocked Flows: An Idealized Modeling Study
Authors: Galewsky Joseph
Published: April 2008

Idealized numerical simulations of moist strongly stratified flow over topography are used to study the processes that control orographic clouds in terrain-blocked flows as a joint function of the nondimensional flow parameter Nh/U, the horizontal topographic aspect ratio β, and the Rossby radius of deformation Nh/f. The simulations show the competition between enhanced upstream condensation in the secondary vertically propagating gravity wave and the reduction of condensation owing to enhanced low-level flow deflection. As Nh/U increases above about 1.5, the tendency for flow to be deflected around the barrier reduces cloud formation in the primary gravity wave over the ridge, while increasing β expands low-level clouds over a broader upstream area. Ice clouds may form aloft in the secondary vertically propagating gravity wave and extend upstream for several hundred kilometers. In terrain-blocked flows, more than half of the condensate mass develops upstream of the barrier in the secondary gravity wave, while in unblocked flows most of the condensate is downstream of the barrier in the primary lee wave. In 2D, none of the flow can be diverted around the barrier, and it therefore produces a much more vigorous hydrologic cycle than over long (β = 8) 3D ridges, increasing upstream lifting and cloud water content by at least a factor of 2, and generating primary wave clouds that are not produced in the 3D case. Rotation reduces the upstream extent of condensation in blocked flows to a region on the order of the radius of deformation and in 3D induces a marked asymmetry in the lifting and condensation upstream of the terrain.
NASA Cold Land Processes Experiment (CLPX 2002/03): Local Scale Observation Site
Authors: Hardy Janet , Davis Robert , Koh Yeohoon , Cline Don , Elder Kelly , Armstrong Richard , Marshall Hans-Peter , Painter Thomas , Saint-Martin Gilles Castres , DeRoo Roger , Sarabandi Kamal , Graf Tobias , Koike Toshio , McDonald Kyle
Published: April 2008

The local scale observation site (LSOS) is the smallest study site (0.8 ha) of the 2002/03 Cold Land Processes Experiment (CLPX) and is located within the Fraser mesocell study area. It was the most intensively measured site of the CLPX, and measurements here had the greatest temporal component of all CLPX sites. Measurements made at the LSOS were designed to produce a comprehensive assessment of the snow, soil, and vegetation characteristics viewed by the ground-based remote sensing instruments. The objective of the ground-based microwave remote sensing was to collect time series of active and passive microwave spectral signatures over snow, soil, and forest, which is coincident with the intensive physical characterization of these features. Ground-based remote sensing instruments included frequency modulated continuous wave (FMCW) radars operating over multiple microwave bandwidths; the Ground-Based Microwave Radiometer (GBMR-7) operating at channels 18.7, 23.8, 36.5, and 89 GHz; and in 2003, an L-, C-, X- and Ku-band scatterometer radar system. Snow and soil measurements included standard snow physical properties, snow wetness, snow depth transects, and soil moisture. The stem and canopy temperature and xylem sap flux of several trees were monitored continuously. Five micrometeorological towers monitored ambient conditions and provided forcing datasets for 1D snow and soil models. Arrays of pyranometers (0.3–3 μm) and a scanning thermal radiometer (8–12 μm) characterized the variability of radiative receipt in the forests. A field spectroradiometer measured the hyperspectral hemispherical-directional reflectance of the snow surface. These measurements, together with the ground-based remote sensing, provide the framework for evaluating and improving microwave radiative transfer models and coupling them to land surface models. The dataset is archived at the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado.
The Effect of Breaking Waves on a Coupled Model of Wind and Ocean Surface Waves. Part I: Mature Seas
Authors: Kukulka Tobias , Hara Tetsu
Published: April 2008

This is the first of a two-part investigation of a coupled wind and wave model that includes the enhanced form drag of breaking waves. In Part I here the model is developed and applied to mature seas. Part II explores the solutions in a wide range of wind and wave conditions, including growing seas. Breaking and nonbreaking waves induce air-side fluxes of momentum and energy above the air–sea interface. By balancing air-side momentum and energy and by conserving wave energy, coupled nonlinear advance–delay differential equations are derived, which govern simultaneously the wave and wind field. The system of equations is closed by introducing a relation between the wave height spectrum and wave dissipation due to breaking. The wave dissipation is proportional to nonlinear wave interactions, if the wave curvature spectrum is below the “threshold saturation level.” Above this threshold the wave dissipation rapidly increases so that the wave height spectrum is limited. The coupled model is applied to mature wind-driven seas for which the wind forcing only occurs in the equilibrium range away from the spectral peak. Modeled wave height curvature spectra as functions of wavenumber k are consistent with observations and transition from k1/2 at low wavenumbers to k0 at high wavenumbers. Breaking waves affect only weakly the wave height spectrum. Furthermore, the wind input to waves is dominated by nonbreaking waves closer to the spectral peak. Shorter breaking waves, however, can support a significant fraction, which increases with wind speed, of the total air–sea momentum flux.
An Intercomparison of Ground-Based Solar FTIR Measurements of Atmospheric Gases at Eureka, Canada
Authors: Paton-Walsh C. , Mittermeier R. L. , Bell W. , Fast H. , Jones N. B. , Meier A.
Published: April 2008

The authors report the results of an intercomparison of vertical column amounts of hydrogen chloride (HCl), hydrogen fluoride (HF), nitrous oxide (N2O), nitric acid (HNO3), methane (CH4), ozone (O3), carbon dioxide (CO2), and nitrogen (N2) derived from the spectra recorded by two ground-based Fourier transform infrared (FTIR) spectrometers operated side-by-side using the sun as a source. The procedure used to record spectra and derive vertical column amounts follows the format of previous instrument intercomparisons organized by the Network for the Detection of Atmospheric Composition Change (NDACC), formerly known as the Network for Detection of Stratospheric Change (NDSC).

For most gases the differences were typically around 3%, and in about half of the results the error bars given by the standard deviation of the measurements from each instrument did not overlap. The worst level of agreement was for HF where differences of over 5% were typical. The level of agreement achieved during this intercomparison is a little worse than that achieved in previous intercomparisons between ground-based FTIR spectrometers.
Examining Charging Agreement Between Police and Prosecutors in Rape Cases
Authors: Holleran David , Beichner Dawn , Spohn Cassia
Published: April 2008

Although prior research has contributed to understanding of the factors that influence sexual assault case processing, it has primarily been viewed through the prosecutorial lens. The authors assert that a prosecutor’s charging decision involves not only a decision to file or reject the charge but, assuming that the case is not rejected, also a decision regarding the charge that should be filed. Accordingly, they examined the congruence between the charge filed by police at arrest with the charge filed by the prosecutor. The results indicate that charging agreement between police and prosecutors in rape cases is governed by a legal sufficiency framework in Philadelphia, where a specialized charging unit receives cases after decisions to charge have been made, and a trial sufficiency framework in Kansas City, Missouri, where a specialized unit makes the decision to charge and uses vertical prosecution from screening through disposition.
Third-Party Intervention and the Civil War Process
Authors: Balch-Lindsay Dylan , Enterline Andrew J. , Joyce Kyle A.
Published: April 2008

What effect do third parties have on the evolution of civil wars? The authors argue that intervention by third parties is central to the civil war process, a process that is characterized by the duration of hostilities and the type of outcome. The authors examine empirically the effect of third-party intervention into civil wars during the period 1816—1997, using the event history framework of competing risks. From the perspective of competing risks, as a civil war endures, it is at risk of experiencing a transition to one of three civil war outcomes in our sample: military victory by the government, military victory by the opposition group, and negotiated settlement. The competing risks approach provides considerably better leverage on the dynamic qualities of civil wars and, in particular, the influence of interventions by third parties. The analysis suggests that third-party interventions can be decisive in the evolution of civil wars and that third-party interventions have a different effect on the duration than different civil war outcomes. The results show that third-party intervention decreases the time until the supported group achieves military victory. Furthermore, third-party interventions, on both the government and opposition sides, increase the time until a negotiated settlement.
A Functional Analysis of Teachers' Instructions
Authors: Todd Richard Watson , Chaiyasuk Intisarn , Tantisawetrat Nuantip
Published: April 2008

Instructions are an under-researched aspect of classroom discourse. In this paper, we attempt to describe the functional structure of teacher instructions using the framework proposed by Sinclair and Coulthard (1975). We examine nine directing transactions or sets of instructions from four lessons taught on an English for Academic Purposes course at a Thai university. The directing transactions were video recorded and transcribed, and the functions identified from the teacher comments in an interview. The frequency of the various types of exchange and move in the discourse, correspondences between exchanges and moves, and pairs of exchanges and moves which co-occur significantly frequently were identified. From these, a potential structure of directing transactions is suggested. This structure starts with a boundary exchange which is followed by one or more instruction exchanges. The teacher instructions can also include insertion and inform exchanges, and usually end with a further instruction exchange.
Deriving Unknown Word Meaning from Context
Authors: Kaivanpanah Shiva , Alavi Mohammad
Published: April 2008

Language teachers often encourage L2 readers to guess the meaning of unknown words in texts. This paper argues that before any statements about the value of guessing can be made, it is necessary to show how reliable learners' guesses are. To this end, the present study investigates how accurately EFL learners assess their understanding of unknown words, and whether language proficiency and gender influence their self-assessment. The study was carried out in three phases. In phase one, participants (N = 110) took a proficiency test and were asked to study a text in which 40 items were highlighted by the researcher on the basis of words that were unfamiliar to them. They were required to assess their understanding of the meaning of unknown words on a four-point scale. In phase two, they provided a translation, synonym, antonym, or an explanation of the unknown words. In phase three, they received the same self-assessment sheet to reassess their understanding of unknown words. The results indicated that learners' assessments are not reliable. Moreover, it was found that proficiency in the L2 and gender influence learners' self-assessment.
School Attendance Revisited
Authors: Steward Robbie J. , Devine Steward Astin , Blair Jonathan , Jo Hanik , Hill Martin F.
Published: April 2008

Urban African American first-year high school students' absenteeism was found to be negatively related to grade point average (GPA) and avoidance as a means of coping (use of substances as a way to escape—food, alcohol, smoking, caffeine, etc.) and positively related to use of social support as a means of coping (efforts to stay emotionally connected with people through reciprocal problem solving and expression of affect). Nonattenders tend to have lower GPAs, report using avoidance less often as a means of coping, and report using social support more often. In other words, those students who attend school most frequently tend to have higher GPAs, use avoidance more often as a means of coping, and use members of their social support less often than do those who have more absences. Implications are discussed for educational reform, school counseling service delivery, and future research.
Using rap and Jamaican dance hall music in the secondary music classroom
Authors: Minott Mark
Published: April 2008

This article reports on a study carried out in a secondary school in the Island of Jamaica. One grade 7 class ( n=20) and one grade 9 class ( n = 23) were taught a six-week unit of lessons aimed at facilitating student listening, performing and composing. Rap and Jamaican dance hall music were used as the stimulus for students' rhythmic accompaniment compositions. Students performed their accompaniments and completed a brief questionnaire at the end of the unit. Students reported that the rap and dance hall music were a positive influence on their enjoyment of the unit. Listening skills were weak across both classes, and, overall, the grade 9 students performed at a higher level of skill than the grade 7 students. It is recommended that `directed listening' be emphasized in music classes, and that students be allowed time to self-reflect on their musical experiences.
From the museum to the music classroom: teaching the umrhubhe as an ensemble instrument
Authors: Dontsa Luvuyo
Published: April 2008

While there is a keen interest in indigenous African instrumental music among South African university music students, indigenous music instruments such as the umrhubhe (musical bow without a calabash resonator) have not found their way into the classroom. Most music departments focus on the teaching and learning of western instruments for instruction. The purpose of the article is to discuss the construction, performance and pedagogy of the umrhubhe. The study also introduces the umrhubhe as an ensemble instrument at primary and tertiary levels of education and demonstrates the techniques of teaching the instrument, focusing on its origins, distribution, craftsmanship, handling, bowing, sound-production, resonating and whistling. A song and dance in which the umrhubhe plays a prominent role is used for illustration. The article concludes with a brief discussion of the implications of teaching the umrhubhe in South African music education.
A Theory of the Preferred Worker: A Structural Explanation for Black Male Dominance in Basketball
Authors: Brooks Scott N. , McKail Michael A.
Published: April 2008

Black males' `dominance' in basketball is taken for granted and often explained in terms of racial difference and socio-environmental factors. However, this is only one side of the coin. Power needs to be considered for a fuller understanding. This article does this, providing a structural perspective of black male integration into basketball that builds from Edna Bonacich's work on labor and group relations. An occupational niche is two-way; a group finds and occupies a niche that they have been given access to by a hiring group. Black males do not dominate the collegiate and professional ranks of basketball simply because of ability. They were given access to the opportunity because it benefited capitalist interests and because of their marginalized position in society. In this specific context, they represent the most profitable labor source.
The Limits of Labor Exclusion: Redefining the Politics of Split Labor Markets under Globalization
Authors: Jihye Chun Jennifer
Published: April 2008

Although exclusion has defined union politics for much of the 20th century, its limits are clear today. Union membership and capacity is declining, and historically disadvantaged workers such as racialized immigrants and women with whom unions have weak linkages are employed in expanding sectors of the low-paid, service economy. By conducting a comparative historical analysis of the US and South Korean labor movements, this article argues that shifts in the balance of power among labor, capital and the state under processes of globalization have fueled more inclusive directions for labor. Contrary to conventional wisdom, workers in the lower tier — a group commonly perceived as lacking the resources and power to challenge downgraded forms of employment — are pivotal to overcoming the exclusionary legacies of the past. The weakening basis of power for workers in the upper tier, the reconstitution of the lower tier, and social movement legacies play a major role in transforming the state of labor politics.
The Evolution of Urban Society and Social Changes in Sports Participation At the Grassroots in China
Authors: Huan Xiong
Published: April 2008

Since the 1980s the `economic reformation'1 has played a crucial role in leading China to a fundamental change in every aspect of its society. This change accelerated a new process of urbanization. In conjunction with the vigorous economic, political and social transformations caused by urbanization, sport in China has undergone a comprehensive process of industrialization, commercialization, decentralization and privatization (Wu, 1999). Urbanization has changed the infrastructure of sport, sports values and forms of participation. Against this background, sports participation in China has emerged with new spaces, forms, contents and concepts. Although elite sport has still been tightly controlled by the state as a political instrument, sport and exercise at the grassroots has become an individual and social activity as a new feature in Chinese urban life. The Chinese people have benefited from increased opportunities and have made great progress in sports participation.
Intimate Partner Violence Among Pregnant Thai Women
Authors: Thananowan Nanthana , Heidrich Susan M.
Published: April 2008

The purposes of this study are to describe intimate partner violence (IPV) among pregnant women in Thailand and compare maternal characteristics, health practices during pregnancy, and maternal health between abused and nonabused pregnant women. Of 475 pregnant Thai women, 13.1% report ever being abused, whereas 4.8% report physical abuse during pregnancy. Women abused during pregnancy, compared to nonabused women, are more likely to be younger, unmarried, have low income, be unemployed, and report that the pregnancy was unwanted. They also report lower levels of positive health practices and higher levels of depressive symptoms. Results demonstrate a need for screening of IPV among pregnant Thai women.
A Descriptive Analysis of Patient Education Courses in Undergraduate and Graduate Health Education Programs
Authors: Gail-Hinckley Heitzer Julia , McKenzie James F. , Amschler Denise H. , Bock William
Published: April 2008

Patient education is a necessary component of quality health care, yet little attention has been given to the preparation of health educators to work in that setting. This study seeks to determine the status of and content in patient education courses offered in professional preparation programs. Results show that 9% of respondents offered a patient education course in their academic unit, whereas 18% indicated that such a course was offered in another unit on campus. It appears there is not agreement between university faculty members and practicing patient educators on what should be taught in such a course. In addition, no significant relationship is found between (a) programs with accreditation or approval and offering a patient education course and (b) programs that prepared students for the Certified Health Education Specialist examination and offering a patient education course. Recommendations are offered for improving the preparation of health educators for the medical care setting.
Interparty Differences in Elite Support for Presidential Nomination Candidates
Authors: Steger Wayne P.
Published: April 2008

Studies of the 1970s and 1980s viewed the political party insiders as having little influence on the selection of the presidential nominees. Recent studies, however, find a significant effect for party elite endorsements in presidential nomination campaigns. This study presents a theory of elite influence in the postreform presidential nomination system and analyzes patterns of elite party endorsements to address questions of when and why elites converge on a preferred candidate. Both party- and candidate-centric factors appear to affect elite endorsements of presidential candidates. Elite elected officials are mainly motivated to have a nominee with electoral appeal. Fewer elite Democratic elected officials endorse presidential candidates, they endorse later, and they tend to divide their endorsements among the presidential candidates to a greater degree than do elite Republican elected officials.
Assessment in Early Childhood
Authors: Snyder Patricia A. , Wixson Corinne S. , Talapatra Devadrita , Roach Andrew T.
Published: April 2008

The current emphasis on alignment of early learning guidelines, assessment, curricular practices, and accountability in early education and care systems has provided an opportunity to revisit and refine early childhood assessment practices. Practitioners, researchers, and policy makers are increasingly interested in developing instruction-focused assessment strategies that have instructional and intervention validity. In particular, progress is being made in the development and validation of universal screening assessments and progress-monitoring methods that can support the application of response-to-intervention models in early childhood settings. This article provides a brief review of select assessment tools in early childhood that demonstrate instructional validity. The authors suggest future directions for strengthening the instructional and intervention validity of early childhood assessments in the context of response-to-intervention frameworks.
Use of Laparoscopy in Evaluation and Treatment of Penetrating and Blunt Abdominal Injuries
Authors: Kaban Gordie K. , Novitsky Yuri W. , Perugini Richard A. , Haveran Liam , Czerniach Donald , Kelly John J. , Litwin Demetrius E.M.
Published: April 2008

Use of laparoscopy in penetrating trauma has been well established; however, its application in blunt trauma is evolving. The authors hypothesized that laparoscopy is safe and feasible as a diagnostic and therapeutic modality in both the patients with penetrating and blunt trauma. Trauma registry data and medical records of consecutive patients who underwent laparoscopy for abdominal trauma were reviewed. Over a 4-year period, 43 patients (18 blunt trauma / 25 penetrating trauma) underwent a diagnostic laparoscopy. Conversion to laparotomy occurred in 9 (50%) blunt trauma and 9 (36%) penetrating trauma patients. Diagnostic laparoscopy was negative in 33% of blunt trauma and 52% of penetrating trauma patients. Sensitivity/specificity of laparoscopy in patients with blunt and penetrating trauma was 92%/100% and 90%/100%, respectively. Overall, laparotomy was avoided in 25 (58%) patients. Use of laparoscopy in selected patients with blunt and penetrating abdominal trauma is safe, minimizes nontherapeutic laparotomies, and allows for minimal invasive management of selected intra-abdominal injuries.
Characteristics and outcomes of patients with chronic myeloid leukemia and T315I mutation following failure of imatinib mesylate therapy
Authors: Jabbour Elias , Kantarjian Hagop , Jones Dan , Breeden Megan , Garcia-Manero Guillermo , O'Brien Susan , Ravandi Farhad , Borthakur Gautam , Cortes Jorge
Published: April 2008

Chronic myeloid leukemia (CML) with T315I mutation has been reported to have poor prognosis. We analyzed 27 patients with T315I, including 20 who developed T315I after imatinib failure (representing 11% of 186 patients with imatinib failure), and 7 of 23 who developed new mutations after second tyrosine kinase inhibitor (TKI). Median follow-up from mutation detection was 18 months. At the time of T315I detection, 10 were in chronic phase (CP), 9 in accelerated phase, and 8 in blast phase. Except for the lack of response to second TKIs (P = .002), there was no difference in patient characteristics and outcome between patients with T315I and those with other or no mutations. Patients in CP had a 2-year survival rate of 87%. Although the T315I mutation is resistant to currently available TKIs, survival of patients with T315I remains mostly dependent on the stage of the disease, with many CP patients having an indolent course.
Structure and expression pattern of Oct4 gene are conserved in vole Microtus rossiaemeridionalis
Authors: Medvedev Sergey P , Shevchenko Alexander I , Elisaphenko Eugene A , Nesterova Tatyana B , Brockdorff Neil , Zakian Suren M
Published: April 2008

Background

Oct4 is a POU-domain transcriptional factor which is essential for maintaining pluripotency in several mammalian species. The mouse, human, and bovine Oct4 orthologs display a high conservation of nucleotide sequence and genomic organization.

Results

Here we report an isolation of a common vole (Microtus rossiaemeridionalis) Oct4 ortholog. Organization and exon-intron structure of vole Oct4 gene are similar to the gene organization in other mammalian species. It consists of five exons and a regulatory region including the minimal promoter, proximal and distal enhancers. Promoter and regulatory regions of the vole Oct4 gene also display a high similarity to the corresponding regions of Oct4 in other mammalian species, and are active during the transient transfection within luciferase reporter constructs into mouse P19 embryonic carcinoma cells and TG-2a embryonic stem cells. The vole Oct4 gene expression is detectable starting from the morula stage and until day 17 of embryonic development.

Conclusion

Genomic organization of this gene and its intron-exon structure in vole are identical to those in all previously studied species: it comprises five exons and the regulatory region containing several conserved elements. The activity of the Oct4 gene in vole, as well as in mouse, is confined only to pluripotent cells.
Coexpression of GM-CSF and antigen in DNA prime-adenoviral vector boost immunization enhances polyfunctional CD8+ T cell responses, whereas expression of GM-CSF antigen fusion protein induces autoimmunity
Authors: Tenbusch Matthias , Kuate Seraphin , Tippler Bettina , Gerlach Nicole , Schimmer Simone , Dittmer Ulf , Überla Klaus
Published: April 2008

Background

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has shown promising results as a cytokine adjuvant for antiviral vaccines and in various models of tumor gene therapy. To explore whether the targeting of antigens to GM-CSF receptors on antigen-presenting cells enhances antigen-specific CD8 T-cell responses, fusion proteins of GM-CSF and ovalbumin (OVA) were expressed by DNA and adenoviral vector vaccines. In addition, bicistronic vectors allowing independent expression of the antigen and the cytokine were tested in parallel.

Results

In vitro, the GM-CSF ovalbumin fusion protein (GM-OVA) led to the better stimulation of OVA-specific CD8+ T cells by antigen-presenting cells than OVA and GM-CSF given as two separate proteins. However, prime-boost immunizations of mice with DNA and adenoviral vector vaccines encoding GM-OVA suppressed CD8+ T-cell responses to OVA. OVA-specific IgG2a antibody levels were also reduced, while the IgG1 antibody response was enhanced. Suppression of CD8+ T cell responses by GM-OVA vaccines was associated with the induction of neutralizing antibodies to GM-CSF. In contrast, the coexpression of GM-CSF and antigens in DNA prime adenoviral boost immunizations led to a striking expansion of polyfunctional OVA-specific CD8+ T cells without the induction of autoantibodies.

Conclusion

The induction of autoantibodies suggests a general note of caution regarding the use of highly immunogenic viral vector vaccines encoding fusion proteins between antigens and host proteins. In contrast, the expansion of polyfunctional OVA-specific CD8+ T cells after immunizations with bicistronic vectors further support a potential application of GM-CSF as an adjuvant for heterologous prime-boost regimens with genetic vaccines. Since DNA prime adenoviral vector boost regimenes are presently considered as one of the most efficient ways to induce CD8+ T cell responses in mice, non-human primates and humans, further enhancement of this response by GM-CSF is a striking observation.
Surfactant proteins SP-B and SP-C and their precursors in bronchoalveolar lavages from children with acute and chronic inflammatory airway disease
Authors: Tafel Oliver , Latzin Philipp , Paul Karl , Winter Tobias , Woischnik Markus , Griese Matthias
Published: April 2008

Background

The surfactant proteins B (SP-B) and C (SP-C) are important for the stability and function of the alveolar surfactant film. Their involvement and down-regulation in inflammatory processes has recently been proposed, but their level during neutrophilic human airway diseases are not yet known.

Methods

We used 1D-electrophoresis and Western blotting to determine the concentrations and molecular forms of SP-B and SP-C in bronchoalveolar lavage (BAL) fluid of children with different inflammatory airway diseases. 21 children with cystic fibrosis, 15 with chronic bronchitis and 14 with pneumonia were included and compared to 14 healthy control children.

Results

SP-B was detected in BAL of all 64 patients, whereas SP-C was found in BAL of all but 3 children; those three BAL fluids had more than 80% neutrophils, and in two patients, who were re-lavaged later, SP-C was then present and the neutrophil count was lower. SP-B was mainly present as a dimer, SP-C as a monomer. For both qualitative and quantitative measures of SP-C and SP-B, no significant differences were observed between the four evaluated patient groups.

Conclusion

Concentration or molecular form of SP-B and SP-C is not altered in BAL of children with different acute and chronic inflammatory lung diseases. We conclude that there is no down-regulation of SP-B and SP-C at the protein level in inflammatory processes of neutrophilic airway disease.
Morphology and function of cryopreserved whole ovine ovaries after heterotopic autotransplantation
Authors: Grazul-Bilska Anna T , Banerjee Jashoman , Yazici Ilker , Borowczyk Ewa , Bilski Jerzy J , Sharma Rakesh K , Siemionow Maria , Falcone Tommaso
Published: April 2008

Background

The objective of this study was to perform complex characterization of cryopreserved and then autotransplanted ovaries including determination of the ability to respond to in vivo follicle stimulating hormone (FSH)-treatment, fertilizability of retrieved oocytes, and morphology, vascularization, cellular proliferation and apoptosis in sheep.

Methods

Mature crossbred ewes were divided into two groups; an intact (control) group (n = 4), and autotransplanted group (n = 4) in which oophorectomy was performed laparoscopically and ovaries with intact vascular pedicles frozen, thawed and transplanted back into the same animal at a different site. Approximately five months after autotransplantation, estrus was synchronized, ewes were treated with FSH, and ovaries were collected. For all ovaries, number of visible follicles was determined, and collected cumulus oocyte complexes (COC) were matured and fertilized in vitro. Remaining ovarian tissues were fixed for evaluation of morphology, expression of factor VIII (marker of endothelial cells), vascular endothelial growth factor (VEGF; expressed by pericytes and smooth muscle cells), and smooth muscle cell actin (SMCA; marker of pericytes and smooth muscle cells), and cellular proliferation and apoptosis. Two fully functional ovaries were collected from each control ewe (total 8 ovaries).

Results

Out of eight autotransplanted ovaries, a total of two ovaries with developing follicles were found. Control ewes had 10.6 +/- 2.7 follicles/ovary, oocytes were in vitro fertilized and developed to the blastocyst stage. One autotransplanted ewe had 4 visible follicles from which 3 COC were collected, but none of them was fertilized. The morphology of autotransplanted and control ovaries was similar. In control and autotransplanted ovaries, primordial, primary, secondary, antral and preovulatory follicles were found along with fully functional vascularization which was manifested by expression of factor VIII, VEGF and SMCA. Proliferating cells were detected in follicles, and the rate of apoptosis was minimal in ovaries of control and autotransplanted ovaries.

Conclusion

These data demonstrate successful autotransplantation of a portion of frozen/thawed ovaries manifested by restoration of selected ovarian function including in vitro maturation of collected oocytes, presence of follicles from several stages of folliculogenesis and blood vessels expressing specific markers of vascularization, and proliferation and apoptosis of ovarian cells. Thus, heterotopic autotransplantation of a whole frozen/thawed ovary allows for development of preovulatory follicles, oocyte growth, and for restoration of vascularization and cellular function. However, additional improvements are required to enhance the efficiency of autotransplantation of frozen/thawed ovaries to produce more oocytes.
An intensivist-led tracheostomy review team is associated with shorter decannulation time and length of stay: a prospective cohort study
Authors: Tobin Antony E , Santamaria John D
Published: April 2008

Introduction

Without specific strategies to address tracheostomy care on the wards, patients discharged from the intensive care unit (ICU) with a tracheostomy may receive suboptimal care. We formed an intensivist-led multidisciplinary team to oversee ward management of such patients. To evaluate the service, we compared outcomes for the first 3 years of the service with those in the year preceding the service.

Methods

Data were prospectively collected over the course of 3 years on ICU patients not under the care of the ear, nose, and throat unit who were discharged to the ward with a tracheostomy and compared with outcomes in the year preceding the introduction of the service. Principal outcomes were decannulation time, length of stay after ICU discharge, and stay of less than 43 days (upper trim point for the disease-related group [DRG] for tracheostomy). Analysis included trend by year and multivariable analysis using a Cox proportional hazards model. P values of less than 0.05 were assumed to indicate statistical significance. As this was a quality assurance project, ethics approval was not required.

Results

Two hundred eighty patients were discharged with a tracheostomy over the course of a 4-year period: 41 in 2003, 60 in 2004, 95 in 2005, and 84 in 2006. Mean age was 61.8 (13.1) years, 176 (62.9%) were male, and mean APACHE (Acute Physiology and Chronic Health Evaluation) II score was 20.4 (6.4). Length of stay after ICU decreased over time (30 [13 to 52] versus 19 [10 to 34] days; P < 0.05 for trend), and a higher proportion of decannulated patients were discharged under the upper DRG trim point of 43 days (48% versus 66%; P < 0.05). Time to decannulation after ICU discharge decreased (14 [7 to 31] versus 7 [3 to 17] days; P < 0.01 for trend). Multivariate analysis showed that the hazard for decannulation increased by 24% (3% to 49%) per year.

Conclusion

An intensivist-led tracheostomy team is associated with shorter decannulation time and length of stay which may result in financial savings for institutions.
Separation of splenic red and white pulp occurs before birth in a LTαβ-independent manner
Authors: Vondenhoff Mark F R , Desanti Guillaume E , Cupedo Tom , Bertrand Julien Y , Cumano Ana , Kraal Georg , Mebius Reina E , Golub Rachel
Published: April 2008

For the formation of lymph nodes and Peyer’s patches, lymphoid tissue inducer (LTi) cells are crucial in triggering stromal cells to recruit and retain hematopoietic cells. Although LTi cells have been observed in fetal spleen, not much is known about fetal spleen development and the role of LTi cells in this process. Here, we show that LTi cells collect in a periarteriolar manner in fetal spleen at the periphery of the white pulp anlagen. Expression of the homeostatic chemokines can be detected in stromal and endothelial cells, suggesting that LTi cells are attracted by these chemokines. As lymphotoxin (LT)α1β2 can be detected on B cells but not LTi cells in neonatal spleen, starting at 4 days after birth, the earliest formation of the white pulp in fetal spleen occurs in a LTα1β2-independent manner. The postnatal development of the splenic white pulp, involving the influx of T cells, depends on LTα1β2 expressed by B cells.
Novel Expression and Direct Effects of Adiponectin in the Rat Testis
Authors: Caminos J. E. , Nogueiras R. , Gaytán F. , Pineda R. , González C. R. , Barreiro M. L. , Castaño J. P. , Malagón M. M. , Pinilla L. , Toppari J. , Diéguez C. , Tena-Sempere M.
Published: April 2008

Adiponectin is an adipocyte hormone, with relevant roles in lipid metabolism and glucose homeostasis, recently involved in the control of different endocrine organs, such as the placenta, pituitary and, likely, the ovary. However, whether as described previously for other adipokines, such as leptin and resistin, adiponectin is expressed and/or conducts biological actions in the male gonad remains unexplored. In this study, we provide compelling evidence for the expression, putative hormonal regulation, and direct effects of adiponectin in the rat testis. Testicular expression of adiponectin was demonstrated along postnatal development, with a distinctive pattern of RNA transcripts and discernible protein levels that appeared mostly located at interstitial Leydig cells. Testicular levels of adiponectin mRNA were marginally regulated by pituitary gonadotropins but overtly modulated by metabolic signals, such as glucocorticoids, thyroxine, and peroxisome proliferator-activated receptor-γ, whose effects were partially different from those on circulating levels of adiponectin. In addition, expression of the genes encoding adiponectin receptor (AdipoR)-1 and AdipoR2 was detected in the rat testis, with developmental changes and gonadotropin regulation for AdipoR2 mRNA, and prominent levels of AdipoR1 in seminiferous tubules. Moreover, recombinant adiponectin significantly inhibited basal and human choriogonadotropin-stimulated testosterone secretion ex vivo, whereas it failed to change relative levels of several Sertoli cell-expressed mRNAs, such as stem cell factor and anti-Müllerian hormone. In summary, our data are the first to document the expression, regulation and functional role of adiponectin in the rat testis. Taken together with its recently reported expression in the ovary and its effects on LH secretion and ovarian steroidogenesis, these results further substantiate a multifaceted role of adiponectin in the control of the reproductive axis, which might operate as endocrine integrator linking metabolism and gonadal function.