bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of a MODIS-Based Potential Evapotranspiration Product at the Point Scale
Authors: Kim Jongyoun , Hogue Terri S.
Published: June 2008

This paper outlines the development of a continuous, daily time series of potential evapotranspiration (PET) using Moderate Resolution Imaging Spectroradiometer (MODIS) sensor data from the Terra satellite platform. The approach is based on the Priestley–Taylor equation, incorporating a daily net radiation model during cloudless days. A simple algorithm using “theoretical clear-sky” net radiation (incorporating daily cloud fraction and cloud optical thickness) and PET is then used to estimate net radiation and PET under cloudy conditions. The method requires minimal ground-based observations for initial calibration of regional radiation algorithm coefficients. Point-scale comparisons are undertaken at four flux-tower sites in North America covering a range of hydroclimatic conditions and biomes. Preliminary results at the daily time step for a 4-yr period (2001–04) show good correlation (R2 = 0.89) and low bias (0.34 mm day−1) for three of the more humid sites. Results are further improved when aggregated to the monthly time scale (R2 = 0.95, bias = 0.31 mm day−1). Performance at the semiarid site is less satisfactory (R2 = 0.95, bias = 2.05 mm day−1 at the daily time step). In general, the MODIS-based daily PET estimates derived in this study are promising and show the potential for use in theoretical and operational water resource studies in both gauged and ungauged basins.
Multilag Singular Value Decomposition Analysis of ENSO Convection with Tropical Stratospheric Temperature
Authors: Weare Bryan C.
Published: June 2008

Multilag singular value decomposition (MLSVD) analysis is developed and applied to diagnosing the impact of interannual variations of outgoing longwave radiation (OLR) on tropical stratospheric temperature changes. MLSVD is designed to analyze simultaneously variations at multiple levels and for a large number of temporal lags and leads. The two dominant MLSVDs are strongly related to El Niño–Southern Oscillation (ENSO). The associated patterns of tropical OLR are similar to the canonical ENSO SST patterns with strong negative sign regions stretching along the equator in the eastern and central Pacific. These dominant modes are strongly linked to temperature perturbations at a wide range of lags. At the lowest analyzed level (200 hPa) and zero lag positive temperatures anomalies are in the region of low OLR. In the lower stratosphere near 100 hPa, strong negative temperature perturbations replace the positive values of the lowest level. Higher in the stratosphere near 20 hPa, equatorial temperature perturbations are again positive, but with a more zonally elongated spatial pattern. Overall, the equatorial temperature anomalies propagate slowly to the east, at a speed strongly related to ocean–atmosphere coupling of less than 1 m s−1, and vertically and westward into the stratosphere by Rossby waves with a speed in the range of 30 m s−1.
Model-Based Drought Indices over the United States
Authors: Mo Kingtse C.
Published: June 2008

Drought indices derived from the North American Land Data Assimilation System (NLDAS) Variable Infiltration Capacity (VIC) and Noah models from 1950 to 2000 are intercompared and evaluated for their ability to classify drought across the United States. For meteorological drought, the standardized precipitation index (SPI) is used to measure precipitation deficits. The standardized runoff index (SRI), which is similar to the SPI, is used to classify hydrological drought. Agricultural drought is measured by monthly-mean soil moisture (SM) anomaly percentiles based on probability distributions (PDs). The PDs for total SM are regionally dependent and influenced by the seasonal cycle, but the PDs for SM monthly-mean anomalies are unimodal and Gaussian.

Across the eastern United States (east of 95°W), the indices derived from VIC and Noah are similar, and they are able to detect the same drought events. Indices are also well correlated. For river forecast centers (RFCs) across the eastern United States, different drought indices are likely to detect the same drought events.

The monthly-mean soil moisture (SM) percentiles and runoff indices between VIC and Noah have large differences across the western interior of the United States. For small areas with a horizontal resolution of 0.5° on the time scales of one to three months, the differences of SM percentiles and SRI between VIC and Noah are larger than the thresholds used to classify drought. For the western RFCs, drought events selected according to SM percentiles or SRI derived from different NLDAS systems do not always overlap.
High-Resolution Observations of Insects in the Atmospheric Boundary Layer
Authors: Contreras Robert F. , Frasier Stephen J.
Published: June 2008

High spatial and temporal resolution S-band radar observations of insects in the atmospheric boundary layer (ABL) are described. The observations were acquired with a frequency-modulated continuous-wave (FMCW) radar during the 2002 International H20 Project (IHOP_2002) held in Oklahoma in the months of May and June 2002. During the observational period the boundary layer was convective with a few periods of rain. Rayleigh scattering from particulate scatterers (i.e., insects) dominates the return; however, Bragg scattering from refractive index turbulence is also significant, especially at the top of the afternoon boundary layer. There is a strong diurnal signal in the insect backscatter: minima in the morning and at dusk and maxima at night and midafternoon. Insect number densities and radar cross sections (RCSs) are calculated. The RCS values range from less than 10−12 m2 to greater than 10−7 m2 and likewise have a strong diurnal signal. These are converted to equivalent reflectivity measurements that would be reported by typical meteorological radars. The majority of reflectivity measurements from particulate scatterers ranges from −30 to −5 dBZ; however, intense point scatterers (>10 dBZ) are occasionally present. The results show that although insects provide useful targets for characterization of the clear-air ABL, the requirements for continuous monitoring of the boundary layer are specific to time of day and range from −20 dBZ in the morning to −10 to −5 dBZ in the afternoon and nocturnal boundary layer (NBL).
Evaluation of DBS Wind Measurement Technique in Different Beam Configurations for a VHF Wind Profiler
Authors: Rao I. Srinivasa , Anandan V. K. , Reddy P. Narasimha
Published: June 2008

Atmospheric winds in the troposphere have been observed routinely for many years with wind profiling (VHF and UHF) radars using the Doppler beam swinging (DBS) technique. Accuracy of wind estimates using wind profiling radars with different beam configurations has its limitations due to both the system of observation and atmospheric conditions. This paper presents a quantitative analysis and evaluation of horizontal wind estimation in different beam configurations up to an altitude of 18 km using the mesosphere–stratosphere–troposphere (MST) radar located in Gadanki, India. Horizontal wind velocities are derived in three different ways using two-, three-, and four-beam configurations. To know the performance of each configuration, radar-derived winds have been compared with the winds obtained by simultaneous GPS sonde balloon measurements, which are considered to be a standard reference by default. Results show that horizontal winds measured using three different beam configurations are comparable in general but discrepancy varies from one beam configuration to the other. It is observed that horizontal winds measured using four-beam configuration (east, west, north, and south) have better estimates than the other two-beam configurations. The standard deviation was found to be varying from 1.4 to 2.5 m s−1 and percentage error is about 9.68%–12.73% in four-beam configuration, whereas in other beam configurations the standard deviation is about 1.65–3.9 m s−1 and the percentage error is about 11.29%–15.16% with reference to GPS sonde balloon–measured winds.
A Hybrid ETKF–3DVAR Data Assimilation Scheme for the WRF Model. Part II: Real Observation Experiments
Authors: Wang Xuguang , Barker Dale M. , Snyder Chris , Hamill Thomas M.
Published: June 2008

The hybrid ensemble transform Kalman filter–three-dimensional variational data assimilation (ETKF–3DVAR) system developed for the Weather Research and Forecasting (WRF) Model was further tested with real observations, as a follow-up for the observation system simulation experiment (OSSE) conducted in Part I. A domain encompassing North America was considered. Because of limited computational resources and the large number of experiments conducted, the forecasts and analyses employed relatively coarse grid spacing (200 km) to emphasize synoptic scales. As a first effort to explore the new system with real observations, relatively sparse observation datasets consisting of radiosonde wind and temperature during 4 weeks of January 2003 were assimilated. The 12-h forecasts produced by the hybrid analysis produced less root-mean-square error than the 3DVAR. The hybrid improved the forecast more in the western part of the domain than the eastern part. It also produced larger improvements in the upper troposphere. The overall magnitude of the ETKF ensemble spread agreed with the overall magnitude of the background forecast error. For individual variables and layers, the consistency between the spread and the error was less than the OSSE in Part I. Given the coarse resolution and relatively sparse observation network adopted in this study, caution is warranted when extrapolating these results to operational applications. A case study was also performed to further understand a large forecast improvement of the hybrid during the 4-week period. The flow-dependent adjustments produced by the hybrid extended a large distance into the eastern Pacific data-void region. The much improved analysis and forecast by the hybrid in the data void subsequently improved forecasts downstream in the region of verification. Although no moisture observations were assimilated, the hybrid updated the moisture fields flow dependently through cross-variable covariances defined by the ensemble, which improved the forecasts of cyclone development.
The Initiation and Evolution of Multiple Modes of Convection within a Meso-Alpha-Scale Region
Authors: French Adam J. , Parker Matthew D.
Published: June 2008

On 30 March 2006, a convective episode occurred featuring isolated supercells, a mesoscale convective system (MCS) with parallel stratiform (PS) precipitation, and an MCS with leading stratiform (LS) precipitation. These three distinct convective modes occurred simultaneously across the same region in eastern Kansas. To better understand the mechanisms that govern such events, this study examined the 30 March 2006 episode through a combination of an observation-based case study and numerical simulations. The convective mode was found to be very sensitive to both the environmental thermodynamic and wind shear profiles, with variations in either leading to different convective modes within the numerical simulations. Strong vertical shear and moderate instability led to the development of supercells in western Oklahoma. Strong shear oriented parallel to a surface dryline, coupled with dry air in the middle and upper levels, led to the development of the PS linear MCS in central Kansas. Meanwhile, moderate wind shear coupled with high instability and strong linear forcing led to the development of the LS MCS in eastern Kansas. Absent linear forcing, the moderate shear environment in eastern Kansas was supportive of isolated supercells in the numerical experiments. This suggests that the linear initiation mechanism was key to the development of the LS linear MCS. From the results of this study it is concuded that, for this event, localized environmental variations were largely responsible for the eventual convective mode, with the method of storm initiation having an impact only within the weaker shear environment of eastern Kansas.
Operational Forecaster Uncertainty Needs and Future Roles
Authors: Novak David R. , Bright David R. , Brennan Michael J.
Published: June 2008

Key results of a comprehensive survey of U.S. National Weather Service operational forecast managers concerning the assessment and communication of forecast uncertainty are presented and discussed. The survey results revealed that forecasters are using uncertainty guidance to assess uncertainty, but that limited data access and ensemble underdispersion and biases are barriers to more effective use. Some respondents expressed skepticism as to the added value of formal ensemble guidance relative to simpler approaches of estimating uncertainty, and related the desire for feature-specific ensemble verification to address this skepticism. Respondents reported receiving requests for uncertainty information primarily from sophisticated users such as emergency managers, and most often during high-impact events. The largest request for additional training material called for simulator-based case studies that demonstrate how uncertainty information should be interpreted and communicated.

Respondents were in consensus that forecasters should be significantly involved in the communication of uncertainty forecasts; however, there was disagreement regarding if and how forecasters should adjust objective ensemble guidance. It is contended that whether forecasters directly modify objective ensemble guidance will ultimately depend on how the weather enterprise views ensemble output (as the final forecast or as a guidance supporting conceptual understanding), the enterprise’s commitment to provide the necessary supporting forecast infrastructure, and how rapidly ensemble weaknesses such as underdispersion, biases, and resolution are addressed.

The survey results illustrate that forecasters’ operational uncertainty needs are intimately tied to the end products and services they produce. Thus, it is critical that the process to develop uncertainty information in existing or new products or services be a sustained collaborative effort between ensemble developers, forecasters, academic partners, and users. As the weather enterprise strives to provide uncertainty information to users, it is asserted that addressing the forecaster needs identified in this survey will be a prerequisite to achieve this goal.
Bone Pain, Growth Failure, and Skin Rash After an Upper Respiratory Illness in a Boy with Autism: Possible Association with Altered Retinoid Metabolism
Authors: Mawson Anthony R.
Published: June 2008

Symptoms of bone pain and skin rashes are not uncommon following a variety of infectious illnesses, but the underlying mechanisms are not well understood. The case of a 9-year-old boy with autism was recently described, who was hospitalized because of pain in the right hip, refusal to walk, fatigue, irritability, skin rash, and subsequent gingival swelling after an unspecified upper respiratory illness. The boy was diagnosed with scurvy. However, the gingival symptoms occurred after treatment with indomethacin, which lowers vitamin C levels; severe bone pain and fatigue are also well-documented symptoms of hypervitaminosis A. This review of a case report of a boy with autism provides an opportunity to present a new hypothesis of the mechanism of these postinfection symptoms in the context of an increasingly common condition of childhood.
Risky Sexual Behavior in Gay and Bisexual Men
Authors: Kashubeck-West Susan , Szymanski Dawn M.
Published: June 2008

This study investigated risky sexual behavior in a sample of 209 gay and bisexual men. Using structural equation modeling, the mediating relations of substance use factors (expectations about the sexually enhancing effects of substance use and substance use during sex) between internalized heterosexism (IH) and sensation seeking and unprotected anal intercourse were examined. Expectations that substance use would enhance sexual activity mediated the relationship between IH and risky sexual behavior. Both substance use factors mediated the relationship of sensation seeking to risky sexual behavior. Greater sensation seeking was associated with greater expectations about the sexually enhancing effects of substances, which in turn was associated with greater unprotected anal intercourse. Unexpectedly, less sensation seeking was related to more substance use during sex, which in turn was associated with more risky sexual behavior. Overall, the variables in the model accounted for 66% of the variance in sexual behavior.
An Analysis of Vocational Rehabilitation Services for Consumers with Hearing Impairments who Received College or University Training
Authors: Boutin Daniel L. , Wilson Keith
Published: June 2008

The purpose of this study was to determine the predictive ability of vocational rehabilitation services for deaf and hard of hearing consumers who received college and university training. The RSA-911 database for fiscal year 2004 was analyzed to evaluate the effectiveness of 21 services in leading to competitive employment. A model predicting competitive employment included job search assistance, job placement, maintenance, rehabilitation technology, transportation, information and referral services, and other services. Results from the logistic regression analysis are discussed in relation to the implications to practitioners and educators.
Trends in Outcomes of the Vocational Rehabilitation Program for Adults With Developmental Disabilities: 1995—2005
Authors: Migliore Alberto , Butterworth John
Published: June 2008

This article describes national trends in outcomes of the vocational rehabilitation (VR) program, with a focus on adults with developmental disabilities during the period of 1995 to 2005. Findings show that the VR program has made substantial progress in excluding extended employment from the array of possible employment closures. Efforts are needed, however, to increase the number of people placed in integrated employment and the earnings at closure while reducing the time frame from application to closure. The study suggests that to achieve these results, practices that lead to above-average outcomes should be identified and disseminated to agencies that show below-average outcomes; the Rehabilitation Act should be rigorously interpreted to prioritize self-sufficiency of VR recipients; and data management should be enhanced through better performance measurement and rapid reporting to state VR agencies.
Moisture Transport and Absorption in Multilayer Protective Clothing Fabrics
Authors: Keiser Corinne , Becker Cordula , Rossi Rene M.
Published: June 2008

The distribution of moisture in state-of-the-art firefighter protective clothing was analyzed on a sweating torso. After one hour of sweating, only 35 % of moisture evaporated from the layers, but after another hour of drying out, only about 10 % of the supplied moisture remained in the clothing. Over 75 % of this moisture accumulated in the innermost three layers of the clothing system consisting of five and six layers, respectively. The interaction of the moisture transport properties of the different layers proved to be very important for the distribution of moisture. In particular, the neighboring layer of the underwear turned out to be dominant for the moisture distribution. Depending on its hygroscopic properties, it could even act as a water barrier.
Numerical Analysis of Energy Absorption Mechanism in Multi-ply Fabric Impacts
Authors: Joo Kiho , Tae Jin Kang
Published: June 2008

The energy analysis method was employed for the understanding of impact behavior of multi-ply plain-woven fabric considering the energy of a projectile. A three-element viscoelastic model was used to describe the dynamic behavior of fibers. Yarn slippage on the warp-weft crossover points was considered by updating the element length. Crimp effect was taken into account by assigning some portion of the strain to crimp. Fabric slippage on the clamped area and yarn pullout on the edge of the fabric were also considered. Bending resistance of the fabrics was assumed as the reaction force of a node arising from the curvature of the nodes. The inelastic collision of fabric layers as well as the collision with the projectile was considered. The numerical model describing all of the features was implemented as in-house code. Each of the energy dissipation mechanisms was characterized to clarify the contribution to the total energy absorption and performance of the fabrics against ballistic impacts. Three cases representing no-perforation, mature-perforation, and premature-perforation were chosen to explain different energy dissipation characteristics, depending on the impact velocity. The difference in reaction of each layer with projectile was also examined.
Preventive role of folic acid on the developmental toxicity of phenol in Drosophila melanogaster
Authors: Aşkın H , Uysal H , Altun D
Published: June 2008

Phenol (PN), obtained from coal tar, is used commonly in medical treatments, industrial areas, petroleum refineries, production of glue, fiber, and nylon. PN is used in the production of benzene and it is emitted in the atmosphere by motor vehicles. Folic acid (FA) is an essential nutrient among the B complex group of vitamins. The main aim of this study was to investigate the effects of PN and PN + FA on various developmental stages of Drosophila melanogaster. Different concentrations of PN and PN + FA were administered during the developmental periods of the fly (egg, larva and pupa). When F1 progeny of control and experimental groups were compared, PN was found to extend the process of metamorphosis and decrease the total offspring numbers. However, these negative effects were inhibited by FA treatment at different concentrations (0.25–2.50 mg/kg). These results suggest that FA could effectively inhibit PN-induced abnormalities in developmental stages of Drosophila melanogaster.
JP-8 jet fuel exposure potentiates tumor development in two experimental model systems
Authors: Harris DT , Sakiestewa D , Titone D , He X , Hyde J , Witten M
Published: June 2008

The US Air Force has implemented the widespread use of JP-8 jet fuel in its operations, although a thorough understanding of its potential effects upon exposed personnel is unclear. Previous work has reported that JP-8 exposure is immunosuppressive. Exposure of mice to JP-8 for 1 h/day resulted in immediate secretion of two immunosuppressive agents; namely, interleukin-10 (IL-10) and prostaglandin E2 (PGE2). Thus, it was of interest to determine if jet fuel exposure might promote tumor growth and metastasis. The syngeneic B16 tumor model was used for these studies. Animals were injected intravenously with tumor cells, and lung colonies were enumerated. Animals were also examined for metastatic spread of the tumor. Mice were either exposed to 1000 mg/m3 JP-8 (1 h/day) for 7 days before tumor injection or were exposed to JP-8 at the time of tumor injection. All animals were killed 17 days after tumor injection. In the present study, JP8 exposure potentiated the growth and metastases of B16 tumors in an animal model. Exposure of mice to JP-8 for 1 h/day before tumor induction resulted in an approximately 8.7-fold increase in tumors, whereas those mice exposed to JP8 at the time of tumor induction had a 5.6-fold increase in tumor numbers. Thus, low concentration JP-8 jet fuel exposures have significant immune suppressive effects on the immune system that can result in increased tumor formation and metastases. We have now extended the observations to an experimental subcutaneous tumor model. JP8 exposure at the time of tumor induction in this model did not affect the growth of the tumor. However, JP8-exposed, tumor-bearing animals died at an accelerated rate as compared with air-exposed, tumor-bearing mice.
The Effects of Sex, Gender Role, and Personality Traits on Leader Emergence
Authors: Türetgen Ilknur Özalp , Unsal Pinar , Erdem Inci
Published: June 2008

This study investigated the effects of sex, gender roles, and personality (self-monitoring, self-efficacy, and dominance) on leader emergence in Turkish university students. Two hundred and nineteen business students filled in personality and gender role inventories, and 60 of them were selected by personality and sex to join in a 4-person leaderless group discussion involving a gender-neutral task. At the completion of the sessions, they evaluated each other on leadership perception and preferences. Results showed that the only personality trait predicting leader emergence in Turkish students was self-monitoring. Differing from studies conducted in Western cultures, dominance, self-efficacy, sex, and gender role orientation were not found to predict emergent group leaders. This difference is explained within the context of Turkey's feminine and collectivist cultural characteristics. The study supports the idea that North American research findings on group leadership perceptions should be tested in other cultures. This issue is especially important for global organizations functioning worldwide.
Auditory Reality and Self-Assessment of Hearing
Authors: Noble William
Published: June 2008

Analyses are made of three problem areas in the realm of hearing disorder and its management, all of which are cogently informed by self-assessment: (a) prosthetic technology and the auditory ecology, (b) dimensions of benefit from amplification, and (c) dimensions of disability. Technology and ecology addresses the matter of “fitness for purpose” of different prosthetic schemes, moderated by people's hearing and listening environments (ecologies) and by what they bring to the task of hearing and listening. Dimensions of benefit covers what is achievable with prevailing technology, and also what people are aware of and identify as their needs. Dimensions of disability examines what has been recently learned about the range of hearing functions that need attending to in management of impaired hearing. A closing section provides a portrait of “auditory reality,” whose characteristics may be better appreciated when analyzed in contrast to and comparison with “visual reality.”
Stuart Gatehouse: A Brief Life
Authors: Akeroyd Michael A.
Published: June 2008

Stuart Gatehouse was an internationally renowned auditory scientist whose work on basic research, government policy, and clinical practice has directly improved the quality of life of adult hearing aid users. He addressed issues of relevance to the lives of hearing-impaired adults, especially on the impact of a hearing loss on an individual, the management of hearing loss, and the measurement of the benefits offered by hearing aids. He also influenced practice and service delivery and made major contributions to the delivery of audiological services in the United Kingdom, including chairing a report that directly led to their modernization in Scotland. This article describes his life and career.
The Effects of Cueing Temporal and Spatial Attention on Word Recognition in a Complex Listening Task in Hearing-Impaired Listeners
Authors: Gatehouse Stuart , Akeroyd Michael A.
Published: June 2008

In a complex listening situation such as a multiperson conversation, the demands on an individual's attention are considerable: There will often be many sounds occurring simultaneously, with continual changes in source and direction. A laboratory analog of this was designed to measure the benefit that helping attention (by visual cueing) would have on word identification. These words were presented unpredictably but were sometimes cued with a temporal cue or a temporal-and-spatial cue. Two groups of hearing-impaired, older-adult listeners participated, 57 unaided and 19 aided. There was a small effect of cueing: The cues gave a 2% benefit in word identification. A variety of subsidiary measures were collected, including the Test of Everyday Attention and the Speech, Spatial, & Qualities of Hearing Questionnaire, but their links with the benefits of cueing were few. The results demonstrate the difficulty of cueing attention to improve word recognition in a complex listening situation.
From `General Field Marshal' To `Miss Genocide'
Authors: Förster Larissa
Published: June 2008

The colonial war of 1904—8 in Namibia still features prominently in contemporary Namibian memory culture. Above all, Herero-speaking Namibians have created various practices by which the war is commemorated annually. Seminal are commemorative rituals held in different areas of Namibia and organized by a ritual and social network established in the aftermath of the war. These commemorations provide a stage for the continuous reworking of the memory of defeat and flight, of dispersal, displacement and genocide, but also of survival and reorganization. The employment of uniforms in the commemorative practices of Herero-speaking Namibians is but one example for the way such memory work is also embodied in material culture. Historic as well as more recent developments of Herero memory culture are scrutinized in an appraisal of different images and representations of the past.
Civilization, Violence and Heritage Healing in Liberia
Authors: Rowlands Michael
Published: June 2008

The restoration of public spaces and monuments in post-conflict situations is often associated with negotiation of trauma and reconciliation. The focus of this article is on the restoration of the national museum as a focus for the restoration of pre-civil war order in Liberia. By concentrating on the restoration of commemorative and public ceremonial spaces `as they were', `forgetting' allows the re-emergence of a visual culture that sustains the continuity of an idea of `civilization'.
Expanding Hegemonic Masculinity: The Use of Irony in Young Men’s Stories About Romantic Experiences
Authors: Korobov Neill
Published: June 2008

This study examines the use of irony in young men’s stories about romantic and sexual experiences. Because romantic experiences are central in the constitution of a heterosexual self, and because they are increasingly formulated in relation to traditional masculine norms and the simultaneous avowal and disavowal of effeminacy, they reveal an oscillation between complicity and resistance to hegemonic masculine norms. This oscillation is explored in stories about promiscuity, seduction, and vulnerability. Critical discursive analyses reveal how young men discursively pivot between complicity and resistance to traditional masculine norms, how this oscillation functions in the accomplishment of their romantic identities, how a sense of conventional masculinity is reclaimed, and what these processes reveal about the shifting nature of hegemonic masculinity in contemporary culture.
Mutation spectrum of 122 hemophilia A families from Taiwanese population by LD-PCR, DHPLC, multiplex PCR and evaluating the clinical application of HRM
Authors: Lin Shin-Yu , Su Yi-Ning , Hung Chia-Cheng , Tsay Woei , Chiou Shyh-Shin , Chang Chieh-Ting , Ho Hong-Nerng , Lee Chien-Nan
Published: June 2008

Background

Hemophilia A represents the most common and severe inherited hemorrhagic disorder. It is caused by mutations in the F8 gene, which leads to a deficiency or dysfunctional factor VIII protein, an essential cofactor in the factor X activation complex.

Methods

We used long-distance polymerase chain reaction and denaturing high performance liquid chromatography for mutation scanning of the F8 gene. We designed the competitive multiplex PCR to identify the carrier with exonal deletions. In order to facilitate throughput and minimize the cost of mutation scanning, we also evaluated a new mutation scanning technique, high resolution melting analysis (HRM), as an alternative screening method.

Results

We presented the results of detailed screening of 122 Taiwanese families with hemophilia A and reported twenty-nine novel mutations. There was one family identified with whole exons deletion, and the carriers were successfully recognized by multiplex PCR. By HRM, the different melting curve patterns were easily identified in 25 out of 28 cases (89%) and 15 out of 15 (100%) carriers. The sensitivity was 93 % (40/43). The overall mutation detection rate of hemophilia A was 100% in this study.

Conclusion

We proposed a diagnostic strategy for hemophilia A genetic diagnosis. We consider HRM as a powerful screening tool that would provide us with a more cost-effective protocol for hemophilia A mutation identification.
A randomised controlled trial evaluating family mediated exercise (FAME) therapy following stroke
Authors: Galvin Rose , Cusack Tara , Stokes Emma
Published: June 2008

Background

Stroke is a leading cause of disability among adults worldwide. Evidence suggests that increased duration of exercise therapy following stroke has a positive impact on functional outcome following stroke. The main objective of this randomised controlled trial is to evaluate the impact of additional family assisted exercise therapy in people with acute stroke.

Methods/Design

A prospective multi-centre single blind randomised controlled trial will be conducted. Forty patients with acute stroke will be randomised into either an experimental or control group. The experimental group will receive routine therapy and additional lower limb exercise therapy in the form of family assisted exercises. The control group will receive routine therapy with no additional formal input from their family members. Participants will be assessed at baseline, post intervention and followed up at three months using a series of standardised outcome measures. A secondary aim of the project is to evaluate the impact of the family mediated exercise programme on the person with stroke and the individual(s) assisting in the delivery of exercises using a qualitative methodology. The study has gained ethical approval from the Research Ethics Committees of each of the clinical sites involved in the study.

Discussion

This study will evaluate a structured programme of exercises that can be delivered to people with stroke by their 'family members/friends'. Given that the progressive increase in the population of older people is likely to lead to an increased prevalence of stroke in the future, it is important to reduce the burden of this illness on the individual, the family and society. Family mediated exercises can maximise the carry over outside formal physiotherapy sessions, giving patients the opportunity for informal practice.

Trial Registration

The protocol for this study is registered with the US NIH Clinical trials registry (NCT00666744)
Treatment of pregnant rats with oleoyl-estrone slows down pup fat deposition after weaning
Authors: García-Peláez Beatriz , Vilà Ruth , Remesar Xavier
Published: June 2008

Background

In rats, oral oleoyl-estrone (OE) decreases food intake and body lipid content. The aim of this study was to determine whether OE treatment affects the energy metabolism of pregnant rats and eventually, of their pups; i.e. changes in normal growth patterns and the onset of obesity after weaning.

Methods

Pregnant Wistar rats were treated with daily intragastric gavages of OE in 0.2 ml sunflower oil from days 11 to 21 of pregnancy (i.e. 10 nmol oleoyl-estrone/g/day). Control animals received only the vehicle. Plasma and hormone metabolites were determined together with variations in cellularity of adipose tissue.

Results

Treatment decreased food intake and lowered weight gain during late pregnancy, mainly because of reduced adipose tissue accumulation in different sites. OE-treated pregnant rats' metabolic pattern after delivery was similar to that of controls. Neonates from OE-treated rats weighed the same as those from controls. They also maintained the same growth rate up to weaning, but pups from OE-treated rats slowed their growth rate afterwards, despite only limited differences in metabolite concentrations.

Conclusion

The OE influences on pup growth can be partially buffered by maternal lipid mobilization during the second half of pregnancy. This maternal metabolic "imprinting" may condition the eventual accumulation of adipose tissue after weaning, and its effects can affect the regulation of body weight up to adulthood.
A computational analysis of protein-protein interaction networks in neurodegenerative diseases
Authors: Goñi Joaquín , Esteban Francisco J , de Mendizábal Nieves Vélez , Sepulcre Jorge , Ardanza-Trevijano Sergio , Agirrezabal Ion , Villoslada Pablo
Published: June 2008

Background

Recent developments have meant that network theory is making an important contribution to the topological study of biological networks, such as protein-protein interaction (PPI) networks. The identification of differentially expressed genes in DNA array experiments is a source of information regarding the molecular pathways involved in disease. Thus, considering PPI analysis and gene expression studies together may provide a better understanding of multifactorial neurodegenerative diseases such as Multiple Sclerosis (MS) and Alzheimer disease (AD). The aim of this study was to assess whether the parameters of degree and betweenness, two fundamental measures in network theory, are properties that differentiate between implicated (seed-proteins) and non-implicated nodes (neighbors) in MS and AD. We used experimentally validated PPI information to obtain the neighbors for each seed group and we studied these parameters in four networks: MS-blood network; MS-brain network; AD-blood network; and AD-brain network.

Results

Specific features of seed-proteins were revealed, whereby they displayed a lower average degree in both diseases and tissues, and a higher betweenness in AD-brain and MS-blood networks. Additionally, the heterogeneity of the processes involved indicate that these findings are not pathway specific but rather that they are spread over different pathways.

Conclusion

Our findings show differential centrality properties of proteins whose gene expression is impaired in neurodegenerative diseases.
Surgical options in the management of cystic duct avulsion during laparoscopic cholecystectomy
Authors: Karimian Faramarz , Aminian Ali , Mirsharifi Rasoul , Mehrkhani Farhad
Published: June 2008

Background

Avulsion of cystic duct during laparoscopic cholecystectomy (LC) is not a common intraoperative complication, but may be encountered by any laparoscopic surgeon. Surgeons are rarely familiar with management of this condition.

Methods

Patients with gall stone related problems who were scheduled for LC at the minimal invasive surgery unit of a tertiary referral hospital during a 5 years period (April 2002–April 2007) were prospectively enrolled.

Results

12 cases were identified (incidence: 1.15%). All 12 patients had gallbladder inflammation. Five patients had acute and seven patients had chronic cholecystitis. The avulsed cystic duct (ACD) was managed by clipping in 4, intracorporeal suturing in 3, converting to open surgery with suture ligation in 2, and lonely external drainage in 3 patients. Bile leakage had ceased within 3 days in 2, 14 days in one, and 20 days in the other patient. Bile volume increased gradually in one of the patients, which stopped only after endoscopic sphincterotomy (ES) at 25th postoperative day. No major late complication or mortality occurred.

Conclusion

ACD during LC is a rare complication. Almost all standard methods of treatment yield to successful outcomes with low morbidity. According to the situation, ACD may be successfully managed laparoscopically. Available cystic stump remnant was clipped. Intracorporeal suture ligation was performed when short length of stump precluded clipping. Deeply retracted cystic duct with active bile leak led to conversion to open surgery. With minimal or no bile leak at ACD stump, closed tube drainage of sub-hepatic area was attempted. Persistent bile leak was assumed to be controlled by ES, successfully accomplished in one patient.
UMF-078: A modified flubendazole with potent macrofilaricidal activity against Onchocerca ochengi in African cattle
Authors: deC Bronsvoort Barend M , Makepeace Benjamin L , Renz Alfons , Tanya Vincent N , Fleckenstein Lawrence , Ekale David , Trees Alexander J
Published: June 2008

Background

Human onchocerciasis or river blindness, caused by the filarial nematodeOnchocerca volvulus, is currently controlled using the microfilaricidal drug, ivermectin. However, ivermectin does not kill adultO. volvulus, and in areas with less than 65% ivermectin coverage of the population, there is no effect on transmission. Therefore, there is still a need for a macrofilaricidal drug. Using the bovine filarial nematodeO. ochengi(found naturally in African cattle), the macrofilaricidal efficacy of the modified flubendazole, UMF-078, was investigated.

Methods

Groups of 3 cows were treated with one of the following regimens: (a) a single dose of UMF-078 at 150 mg/kg intramuscularly (im), (b) 50 mg/kg im, (c) 150 mg/kg intraabomasally (ia), (d) 50 mg/kg ia, or (e) not treated (controls).

Results

After treatment at 150 mg/kg im, nodule diameter, worm motility and worm viability (as measured by metabolic reduction of tetrazolium to formazan) declined significantly compared with pre-treatment values and concurrent controls. There was abrogation of embryogenesis and death of all adult worms by 24 weeks post-treatment (pt). Animals treated at 50 mg/kg im showed a decline in nodule diameter together with abrogated reproduction, reduced motility, and lower metabolic activity in isolated worms, culminating in approximately 50% worm mortality by 52 weeks pt. Worms removed from animals treated ia were not killed, but exhibited a temporary embryotoxic effect which had waned by 12 weeks pt in the 50 mg/kg ia group and by 24 weeks pt in the 150 mg/kg ia group. These differences could be explained by the different absorption rates and elimination half-lives for each dose and route of administration.

Conclusion

Although we did not observe any signs of mammalian toxicity in this trial with a single dose, other studies have raised concerns regarding neuro- and genotoxicity. Consequently, further evaluation of this compound has been suspended. Nonetheless, these results validate the molecular target of the benzimidazoles as a promising lead for rational design of macrofilaricidal drugs.
Assessment of stroke volume variation for prediction of fluid responsiveness using the modified FloTrac™ and PiCCOplus™ system
Authors: Hofer Christoph K , Senn Alban , Weibel Luc , Zollinger Andreas
Published: June 2008

Introduction

Stroke volume variation (SVV) has repeatedly been shown to be a reliable predictor of fluid responsiveness. Various devices allow automated clinical assessment of SVV. The aim of the present study was to compare prediction of fluid responsiveness using SVV, as determined by the FloTrac™/Vigileo™ system and the PiCCOplus™ system.

Methods

In patients who had undergone elective cardiac surgery, SVVFloTrac was determined via radial FloTrac sensor, and SVVPiCCO and pulse pressure variation were assessed via a femoral PiCCO catheter. Stroke volume was assessed by transpulmonary thermodilution. All variables were recorded before and after a volume shift induced by a change in body positioning (from 30° head-up position to 30° head-down position). Pearson correlation, t-test, and Bland-Altman analysis were performed. Area under the curve was determined by plotting receiver operating characteristic curves for changes in stroke volume in excess of 25%. P < 0.05 was considered statistically significant.

Results

Body positioning resulted in a significant increase in stroke volume; SVVFloTrac and SVVPiCCO decreased significantly. Correlations of SVVFloTrac and SVVPiCCO with change in stroke volume were similar. There was no significant difference between the areas under the curve for SVVFloTrac and SVVPiCCO; the optimal threshold values given by the receiver operating characteristic curves were 9.6% for SVVFloTrac (sensitivity 91% and specificity 83%) and 12.1% for SVVPiCCO (sensitivity 87% and specificity 76%). There was a clinically acceptable agreement and strong correlation between SVVFloTrac and SVVPiCCO.

Conclusion

SVVs assessed using the FloTrac™/Vigileo™ and the PiCCOplus™ systems exhibited similar performances in terms of predicting fluid responsiveness. In comparison with SVVPiCCO, SVVFloTrac has a lower threshold value.
Gene expression response in target organ and whole blood varies as a function of target organ injury phenotype
Authors: Lobenhofer Edward K , Auman J Todd , Blackshear Pamela E , Boorman Gary A , Bushel Pierre R , Cunningham Michael L , Fostel Jennifer M , Gerrish Kevin , Heinloth Alexandra N , Irwin Richard D , Malarkey David E , Merrick B Alex , Sieber Stella O , Tucker Charles J , Ward Sandra M , Wilson Ralph E , Hurban Patrick , Tennant Raymond W , Paules Richard S
Published: June 2008

This report details the standardized experimental design and the different data streams that were collected (histopathology, clinical chemistry, hematology and gene expression from the target tissue (liver) and a bio-available tissue (blood)) after treatment with eight known hepatotoxicants (at multiple time points and doses with multiple biological replicates). The results of the study demonstrate the classification of histopathological differences, likely reflecting differences in mechanisms of cell-specific toxicity, using either liver tissue or blood transcriptomic data.
Skewing the Th cell phenotype toward Th1 alters the maturation of tumor-infiltrating mononuclear phagocytes
Authors: Nonaka Kenichi , Saio Masanao , Suwa Tatsuhiko , Frey Alan B , Umemura Naoki , Imai Hisashi , Ouyang Guan-Feng , Osada Shinji , Balazs Margit , Adany Roza , Kawaguchi Yoshihiro , Yoshida Kazuhiro , Takami Tsuyoshi
Published: June 2008

Mononuclear phagocytes (MPCs) at the tumor site can be divided into subclasses, including monocyte-lineage myeloid-derived suppressor cells (MDSCs) and the immunosuppressive tumor-infiltrating macrophages (TIMs). Cancer growth coincides with the expansion of MDSCs found in the blood, secondary lymphoid organs, and tumor tissue. These MDSCs are thought to mature into macrophages and to promote tumor development by a combination of growth-enhancing properties and suppression of local antitumor immunoresponses. As little is known about either subset of MPCs, we investigated MPCs infiltrating into murine adenocarcinoma MCA38 tumors. We found that these MPCs displayed immunosuppressive characteristics and a MDSC cell-surface phenotype. Over 70% of the MPCs were mature (F4/80+Ly6C−) macrophages, and the rest were immature (F480+ Ly6C+) monocytes. MPC maturation was inhibited when the cells infiltrated a tumor variant expressing IL-2 and soluble TNF type II receptor (sTNFRII). In addition, the IL-2/sTNFRII MCA38 tumor microenvironment altered the MPC phenotype; these cells did not survive culturing in vitro as a result of Fas-mediated apoptosis and negligible M-CSFR expression. Furthermore, CD4+ tumor-infiltrating lymphocytes (TILs) in wild-type tumors robustly expressed IL-13, IFN-γ, and GM-CSF, and CD4+ TILs in IL-2/sTNFRII-expressing tumors expressed little IL-13. These data suggest that immunotherapy-altered Th cell balance in the tumor microenvironment can affect the differentiation and maturation of MPCs in vivo. Furthermore, as neither the designation MDSC nor TIM can sufficiently describe the status of monocytes/macrophages in this tumor microenvironment, we believe these cells are best designated as MPCs.