bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bulk microphysics parametrization of ice fraction for application in climate models
Authors: Boudala Faisal S. , Isaac George A. 
Published: November 2006

AbstractUsing in situ aircraft measurements of cloud microphysical properties collected in extratropical stratiform clouds during several field programs, a parametrization of the ice‐particle spectrum that includes small ice particles has been developed. This parametrization has been tested using a single prognostic equation developed by Tremblay et al. (1996) for application in a regional model. The addition of small ice‐particles significantly increases the vapour deposition‐rate when the natural atmosphere is assumed to be water saturated, and thus enhances the glaciation of simulated mixed‐phase cloud via the Bergeron–Findeisen process without significantly affecting the other cloud microphysical processes such as riming and particle‐sedimentation rates. After the water vapour pressure in mixed‐phase cloud was modified, based on the scheme of Lord et al. (1984), by weighting the saturation water vapour pressure with ice fraction, it was possible to simulate a more stable mixed‐phase cloud. It was also noted that the ice‐particle concentration (maximum dimension L > 100 µm ) in mixed‐phase cloud is lower on average by a factor of three, and, consequently, the parametrization should be corrected for this effect. After accounting for this effect, the parametrized ice‐fraction agreed well with observation. Copyright © 2006 Royal Meteorological Society
Flow separation and rotor formation beneath two‐dimensional trapped lee waves
Authors: Vosper S. B. , Sheridan P. F. , Brown A.R. 
Published: November 2006

AbstractNumerical simulations of trapped lee waves generated in flow over a two‐dimensional ridge are presented. It is shown that for sufficiently large amplitude waves flow separation occurs beneath the wave crests when a no‐slip lower boundary condition is applied. The occurrence of separation corresponds to rotor motion, or recirculation, under the wave crests. The dependence of the wave‐induced horizontal flow perturbations near the ground on the wave amplitude, wavelength and surface roughness is examined. It is shown that the normalized critical wave amplitude, above which rotors form, is a function of the ratio of the lee‐wave horizontal wavelength to the surface roughness length. This normalized wave amplitude is defined as the ratio of the lee‐wave pressure amplitude within the boundary layer, to the square of the friction velocity.Linearized turbulent equations for motion beneath the wave crests are considered and numerical solutions to the linear problem are compared with results from the simulations. When the waves are of sufficiently small amplitude that flow separation does not occur, the linear flow perturbations are shown to agree closely with the results from the simulations. It is also shown that linear theory provides a useful prediction of the occurrence of rotor formation. © Crown copyright, 2006.
Automated tracking of dry intrusions on satellite water vapour imagery and model output
Authors: Michel Y. , Bouttier F. 
Published: November 2006

AbstractA satellite image‐processing technique has been developed for the identification and tracking of upper‐tropospheric features related to midlatitude synoptic‐scale cyclogenesis. Persistent warm radiance features are detected on water vapour images using an adaptive thresholding technique, tracked using estimations of the motion of the features through displacement and cross‐correlation of successive images, and then screened using both image‐based and model‐based criteria. The aim is the characterization of jet dynamical features and dry intrusions of stratospheric air into the upper troposphere. On a selected sample of events, the resulting trajectories prove to be very consistent with the subjective identification of cyclogenesis events on imagery. In accordance with potential vorticity theory, the detected warm features are correlated with positive anomalies of potential vorticity. This identification technique can be applied to model output, which suggests future applications in forecast verification and data assimilation of midlatitude cyclones. Copyright © 2006 Royal Meteorological Society
Investigation into the wavelength dependence of the aerosol optical depth in the Athens area
Authors: Kaskaoutis D. G. , Kambezidis H. D. 
Published: November 2006

AbstractGround‐based solar spectral irradiance measurements obtained by a spectroradiometer have been used to retrieve the aerosol optical depth, τα, and the Ångström wavelength exponent, α. These measurements were obtained in the Athens centre in May 1995. Exponent α is frequently computed from spectral measurements both from ground‐based photometers and satellite remote sensing retrievals. Although the retrieval of α has been the subject of many studies worldwide, its spectral variation is typically not considered. In this study we analyse the spectral measurements of ln τα versus ln λ, where λ is the wavelength, at six selected wavelengths which cover the spectrum from 340 to 870 nm. It is obvious that there is significant curvature in the ln ta versus ln λ relationship, and the reasons for this are examined. It was found that this curvature depends on both atmospheric turbidity and aerosol optical properties, and a second order polynomial fit provides excellent agreement. The curvature of the polynomial equation becomes greater as the aerosol loading alters from high to low. The curvature is characterized by the second derivative of α, which can be utilized in conjunction with α to characterize the spectral dependence of aerosol optical depth, and can also be used as an indicator of the relative influence of fine‐versus coarse‐mode particles. Copyright © 2006 Royal Meteorological Society
Microwave land emissivity and skin temperature for AMSU‐A and ‐B assimilation over land
Authors: Karbou Fatima , Gérard Élisabeth , Rabier Florence 
Published: November 2006

AbstractAMSU‐A and ‐B measurements are still not extensively used over land surfaces for atmospheric applications. Recent studies have shown that it should now be possible to take advantage of the information content of these instruments provided land emissivity and skin temperature estimates are improved. This paper reports on comparisons between three land‐surface schemes using the Météo‐France four‐dimensional variational (4D‐Var) assimilation system. Firstly, a monthly mean estimated land emissivity atlas using AMSU data is used. A second land‐surface scheme based on direct emissivity calculations is developed to obtain dynamically emissivity values. The third approach is based on the first one with the addition of a dynamic skin temperature estimation based on one AMSU‐A or AMSU‐B window channel. The land‐surface schemes described above have been implemented within the 4D‐Var system and their results have been compared with those of the operational surface scheme (which uses emissivity models). All land schemes have been evaluated by examining the performances of the observation operator for sounding channels prior to the assimilation. With dynamically varying emissivities and/or skin temperatures or with averaged emissivities, the simulations are clearly improved compared with the operational model and many more data pass the quality‐control check. Copyright © 2006 Royal Meteorological Society
Implementation of 1D+4D‐Var assimilation of precipitation‐affected microwave radiances at ECMWF. II: 4D‐Var
Authors: Bauer Peter , Lopez Philippe , Salmond Deborah , Benedetti Angela , Saarinen Sami , Bonazzola Marine 
Published: November 2006

AbstractThis paper presents the operational implementation of a 1D+4D‐Var assimilation system of rain‐affected satellite observations at ECMWF performed on 28 June 2005. The first part describes the methodology and performance analysis of the 1D‐Var retrieval scheme in clouds and precipitation that uses Special Sensor Microwave/Imager (SSM/I) microwave radiance observations for the estimation of total‐column water vapour (TCWV). This part describes the technical implementation of the TCWV observations in 4D‐Var as well as the impact analysis.The effect of the TCWV observations implied by precipitation on the 4D‐Var analyses is significant and the total information content is comparable to that of the SSM/I, High‐resolution InfraRed Sounder and Advanced Microwave Sounding Unit (AMSU‐B) radiances. Regions with systematic drying in the analysis persist throughout the forecast while moistening is removed by precipitation after 1–2 days. The corresponding divergence increments reflect the feedback between moisture and dynamics. Forecast evaluation using model analyses exhibits mostly positive relative‐humidity forecast scores, in particular at 700 hPa and in the Tropics. Some short‐term negative forecast scores are observed for geopotential near 1000 hPa and in the southern hemisphere between days 2–4. Wind scores vary greatly between regions and different forecast lengths. Tropical cyclone tracking forecasts are only slightly affected by a reduced location error spread through the rain assimilation. Comparison to dropsonde observations of wind and temperature shows improvement as does TCWV analysis validation against independent observations from Jason radiometer data. The system has been implemented operationally in June 2005 and will be further developed towards a direct 4D‐Var assimilation of radiances in clouds and precipitation. Copyright © 2006 Royal Meteorological Society
An Ethno‐Methodological Approach to Cannabis and Music Perception, with EEG Brain Mapping in a Naturalistic Setting
Authors: Fachner Jörg 
Published: November 2006

Cannabis is known to change auditory perception and music appreciation as many musicians and music listeners report in narratives, interviews and biographies. An ethnographic pre/post study was conducted in a habituated naturalistic setting, combining qualitative and quantitative methods with four single case studies. Physiological results were gained with a mobile bedside EEG imaging machine in an authentic setting of the consumer's life‐world. Results represent explorative data of participants' spontaneous EEG‐activity, referable to results of psychological and medical studies.Increasing Alpha‐signal strength in parietal association cortex and significant Theta band changes in temporal and on Alpha in occipital areas seem to represent an intraindividual constant EEG correlate of temporarily intensified attention ("high"), resulting in an altered music perception by hyperfocusing on acoustic space and broadened insight into the "space between the notes." THC has a measurable influence on cerebral music processing and seems to enhance acoustic perception temporarily.
Long-term Cognitive and Motor Deficits After Enterovirus 71 Brainstem Encephalitis in Children
Authors: Huang Mei-Chih , Wang Shih-Min , Hsu Yung-Wen , Lin Hui-Chen , Chi Chia-Yu , Liu Ching-Chuan 
Published: November 2006

OBJECTIVES. Several large outbreaks of enterovirus 71 infections have occurred in Taiwan during the past decade. Brainstem encephalitis was the most common neurologic complication. This study was designed to determine the long-term cognitive and motor outcomes of children with enterovirus 71 brainstem encephalitis.
METHODS. We conducted a prospective follow-up study of children who met the case definition for enterovirus 71 brainstem encephalitis. Subjects were stratified into isolated brainstem encephalitis (stage II), autonomic nervous system dysregulation (stage IIIa), and pulmonary edema (stage IIIb). The subjects and their parents or guardians were interviewed using structured questionnaires and received comprehensive cognitive and neurologic examinations. Motor coordination, visual-motor skill, and intellectual ability were evaluated.
RESULTS. Follow-up studies were conducted in 63 previously healthy children with enterovirus 71 brainstem encephalitis (49 stage II, 7 stage IIIa, and 7 stage IIIb). The mean time to follow-up was 2.8 ± 1.0 years (range: 1.4–4.9 years). Boys outnumbered girls by 3 to 2. The mean age at diagnosis was 2.4 ± 1.4 years (range: 0.3–7.1 years). The most common abnormal neurologic findings on admission were altered consciousness (47.6%), followed by abnormal activities of daily living (52.4%), cerebellar dysfunction (17.5%), and cranial nerve palsy (15.9%). At follow-up, 51 of 63 children had no detectable deficits. Among the remaining 12 children, 3 died during the follow-up. The remaining 9 children (14.3%) had residual deficits. Two of these with stage IIIb disease continued to have severe motor and respiratory failure.
CONCLUSIONS. Residual defects were still present in a significant proportion of children with enterovirus 71 brainstem encephalitis at &gt;2 years after their hospitalization. Children with stage II disease were most likely to have residual cerebellar defects. Those with stage IIIb disease continued to have severe respiratory and motor impairment. Long-term follow-up of this cohort is needed to determine the ultimate prognosis.
Two servers in series, studied in terms of a Markov renewal branching process
Authors: Neuts Marcel F. 
Published: November 2006

This paper discusses the transient and limiting behavior of a system of queues, consisting of two service units in tandem in which the second unit has finite capacity. When the second unit reaches full capacity, a phenomenon termed “blocking” occurs. A wide class of rules to resolve blocking is defined and studied in a unified way.The input to the first unit is assumed to be Poisson, the service times in the first unit are independent with a general, common distribution. When the system is not blocked, the second unit releases its customers according to a state-dependent, death process.The analysis of the time-dependence relies heavily on several imbedded Markov renewal processes. In particular, the analog of the busy period for theM/G/1 queue is modeled here as a “Markov renewal branching process”. The study of this process requires the definition of a class of matrix functions which generalizes some classical definitions of matrix function. In terms of these “matrix functions” we are led to consider functional iterates and a matrix analog of Takács' functional equation for the transform of the distribution of the busy period in theM/G/1 model.We further discuss the joint distribution of the queue lengths in units I and II and its marginal and limiting distributions.A final section is devoted to an informal discussion on how the numerical analysis of this system of queues may be organized.
In vitro metabolism of ciclesonide in human nasal epithelial cells
Authors: Sato Hideyuki , Nave Ruediger , Nonaka Takashi , Mochizuki Tsutomu , Takahama Shigehiro , Kondo Shiro 
Published: November 2006

AbstractCiclesonide, a corticosteroid in development for allergic rhinitis, is converted to the pharmacologically active metabolite, desisobutyryl‐ciclesonide (des‐CIC), and des‐CIC is subsequently esterified with fatty acids. Various experiments were performed to investigate ciclesonide metabolism in human nasal epithelial cells (HNEC). Human nasal epithelial cells were incubated with (a) 0.1 µM ciclesonide for 1 h and medium without ciclesonide for up to 24 h, (b) esterase inhibitors for 0.5 h followed by 5 µM ciclesonide for 6 h, or (c) 1 µM des‐CIC for 6 h followed by medium without des‐CIC for up to 24 h. Ciclesonide, des‐CIC and des‐CIC fatty acid conjugate concentrations were determined by high‐performance liquid chromatography with tandem mass spectrometry. The amount of ciclesonide in HNEC decreased approximately 93‐fold from 0.5 to 24 h. In contrast, des‐CIC was present at constant levels throughout the post‐treatment period. Furthermore, fatty acid conjugates of des‐CIC were retained in HNEC up to 24 h post‐treatment. Carboxylesterase and cholinesterase inhibitors decreased ciclesonide metabolism ⩾50%. The total amounts of des‐CIC fatty acid conjugates decreased and the extracellular amounts of des‐CIC increased with time. In conclusion, ciclesonide was rapidly converted to des‐CIC by carboxylesterases and cholinesterases, and des‐CIC underwent reversible fatty acid conjugation in HNEC. Copyright © 2006 John Wiley & Sons, Ltd.
The blood/vascular system in a phylogenetic perspective
Authors: Hartenstein Volker , Mandal Lolitika 
Published: November 2006

AbstractThe genetically and experimentally accessible organs of Drosophila, such as the heart or blood‐forming tissues, have become a fertile ground for systematic projects of gene discovery and for functional studies of gene networks and signaling pathways. One argument justifying this approach is the often‐tacit assumption that clear‐cut homologies can be established between the Drosophila organs and their vertebrate counterparts. Here we investigate this assumption by surveying pertinent aspects of vascular structure and development in different invertebrate phyla, in the hope that this information will help to reveal the ancestral condition of the vascular system. Evolutionary scenarios that derive the structure of the cardiovascular system of extant animal taxa from the ancestral condition will be used to qualify hypotheses regarding homologies that are based on molecular similarities. BioEssays 28: 1203–1210, 2006. © 2006 Wiley Periodicals, Inc.
Born to bind: the BTB protein–protein interaction domain
Authors: Perez‐Torrado Roberto , Yamada Daisuke , Defossez Pierre‐Antoine 
Published: November 2006

AbstractThe BTB domain is a protein–protein interaction motif that is found throughout eukaryotes. It determines a unique tri‐dimensional fold with a large interaction surface. The exposed residues are highly variable and can permit dimerization and oligomerization, as well as interaction with a number of other proteins. BTB‐containing proteins are numerous and control cellular processes that range from actin dynamics to cell‐cycle regulation. Here, we review findings in the field of transcriptional regulation to illustrate how the high variability of the BTB has allowed related transcription factors to evolve different functional abilities. We then report how recent work has showed that, in spite of their high sequence divergence and apparently unrelated functions, many BTB‐containing proteins have at least one shared role: the recruitment of degradation targets to E3 ubiquitin ligase complexes. Taken together, these findings illustrate diverse and convergent functions of a versatile protein–protein interaction domain. BioEssays 28: 1194–1202, 2006. © 2006 Wiley Periodicals, Inc.
Telomere dysfunction: a new player in radiation sensitivity
Authors: Genescà Anna , Martín Marta , Latre Laura , Soler David , Pampalona Judit , Tusell Laura 
Published: November 2006

AbstractHuman individuals often exhibit important differences in their sensitivity to ionising radiation. Extensive literature links radiation sensitivity with impaired DNA repair which is due to a lack of correct functioning in many proteins involved in DNA‐repair pathways and/or in DNA‐damage checkpoint responses. Given that ionising radiation is an important and widespread diagnostic and therapeutic tool, it is important to investigate further those factors and mechanisms that underlie individual radiosensitivity. Recently, evidence is accumulating that telomere function may well be involved in cellular and organism responses to ionising radiation, broadening still further the currently complex and challenging scenario. BioEssays. BioEssays 28: 1172–1180, 2006. © 2006 Wiley Periodicals, Inc.
The molecular basis of neurosensory cell formation in ear development: a blueprint for hair cell and sensory neuron regeneration?
Authors: Fritzsch Bernd , Beisel Kirk W. , Hansen Laura A. 
Published: November 2006

AbstractThe inner ear of mammals uses neurosensory cells derived from the embryonic ear for mechanoelectric transduction of vestibular and auditory stimuli (the hair cells) and conducts this information to the brain via sensory neurons. As with most other neurons of mammals, lost hair cells and sensory neurons are not spontaneously replaced and result instead in age‐dependent progressive hearing loss. We review the molecular basis of neurosensory development in the mouse ear to provide a blueprint for possible enhancement of therapeutically useful transformation of stem cells into lost neurosensory cells. We identify several readily available adult sources of stem cells that express, like the ectoderm‐derived ear, genes known to be essential for ear development. Use of these stem cells combined with molecular insights into neurosensory cell specification and proliferation regulation of the ear, might allow for neurosensory regeneration of mammalian ears in the near future. BioEssays 28: 1181–1193, 2006. © 2006 Wiley Periodicals, Inc.
Molecular mechanisms involved in Ras inactivation: the annexin A6–p120GAP complex
Authors: Grewal Thomas , Enrich Carlos 
Published: November 2006

AbstractIn mammalian cells, a complex network of signaling pathways tightly regulates a variety of cellular processes, such as proliferation and differentiation. New insights from one of the most‐important signaling cascades involved in oncogenesis, the Ras–Raf–MAPK pathway, suggest that the subcellular localisation and assembly of signaling modules of this pathway is crucial to control the biological response. This commonly requires membrane targeting events that are mediated by adaptor/scaffold proteins. Of particular interest is the translocation and complex formation of GTPase‐activating proteins (GAPs), such as p120GAP, at the plasma membrane to inactivate Ras. Recent studies indicate that one member of the annexin family, annexin A6 acts as a targeting protein for p120GAP. This review discusses how annexin A6 modulates the involvement of negative regulators of the Ras–Raf–MAPK pathway contributing to Ras inactivation. BioEssays 28: 1211–1220, 2006. © 2006 Wiley Periodicals, Inc.
Evolution at the host–retrovirus interface
Authors: Gifford Robert J. 
Published: November 2006

AbstractRetroviruses are unusual amongst animal viruses in their capacity to integrate into host genomes and be transmitted vertically to host progeny. Vertebrate genomes contain numerous and diverse retrovirus‐derived sequences reflecting a long co‐evolutionary history during which genome invasion has occurred repeatedly, with wide‐ranging evolutionary consequences. Over the past 10 years, a detailed picture of retroviral diversity throughout vertebrate genomes has emerged, revealing striking and informative patterns that differ markedly across species. The power of these data to deliver far‐reaching insights into the biology and evolution of retroviruses has been significantly advanced by recent studies identifying ongoing genome invasion in wild populations,(1) and by the characterisation of conserved mechanisms of innate antiretroviral defence.(2,3) BioEssays 28: 1153–1156, 2006. © 2006 Wiley Periodicals, Inc.
Lhx2—decisive role in epithelial stem cell maintenance, or just the “tip of the iceberg”?
Authors: Tiede Stephan , Paus Ralf 
Published: November 2006

AbstractStem cell self renewal, maintenance and differentiation are influenced by the convergence of intrinsic cellular signals and extrinsic microenvironmental cues from the surrounding stem cell niche. However, the specific signals involved are often still poorly understood. This is also true for skin epithelial stem cells. Recently, by transcriptionally profiling of embryonic hair progenitors in mice, Rhee et al.1 have managed to define how murine hair follicle epithelial stem cells are specified and maintained in an undifferentiated state. These authors have identified Lhx2 as a transcription factor functionally positioned downstream of signals necessary to specify hair follicle stem cells such as p63 or NFκB, but upstream of signals like Wnt/β‐catenin, Bmp or Shh that are required to drive activated stem cells via the production of transient amplifying cells into terminal differentiation. BioEssays 28: 1157–1160, 2006. © 2006 Wiley Periodicals, Inc.