bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tuberous Sclerosis Complex and Epilepsy: Recent Developments and Future Challenges
Authors: Holmes Gregory L. , Stafstrom Carl E. ,   The Tuberous Sclerosis Study Group
Published: March 2007

Summary: Tuberous sclerosis complex (TSC) is a congenital syndrome characterized by the widespread development of benign tumors in multiple organs, caused by mutations in one of the tumor suppressor genes, TSC1 or TSC2. About 80% of affected patients have a new mutation, and the remaining 20% have inherited a TSC gene mutation from a parent. The disorder affects approximately 1 in 6000 individuals. Cortical tubers are the neuropathological hallmark of TSC. The most common neurological manifestations of TSC are epilepsy, mental retardation, and autistic behavior. Epilepsy occurs in up to 80–90% of patients and is often intractable, with a poor response to anticonvulsant medications.While the molecular basis of TSC is well established, far less is known about the mechanisms of epilepsy in this disorder. In this article, we first summarize known clinical aspects of TSC with emphasis on its neurological features. Then, based on the molecular, pathological, immunohistochemical, neurochemical, and physiological properties of tubers in patients with TSC and in animal models, we discuss possible mechanisms of seizures and epileptogenesis in TSC. Finally, we provide an updated literature review and a consensus statement from the Tuberous Sclerosis Complex Working Group for future research into the mechanisms of epilepsy in TSC.
A QUALITATIVE STUDY OF LINEAR DRIFT-DIFFUSION EQUATIONS WITH TIME-DEPENDENT OR DEGENERATE COEFFICIENTS
Authors: BARTIER JEAN-PHILIPPE , DOLBEAULT JEAN , ILLNER REINHARD , KOWALCZYK MICHAŁ 
Published: March 2007

This paper is concerned with entropy methods for linear drift-diffusion equations with explicitly time-dependent or degenerate coefficients. Our goal is to establish a list of various qualitative properties of the solutions. The motivation for this study comes from a model for molecular motors, the so-called Brownian ratchet, and from a nonlinear equation arising in traffic flow models, for which complex long time dynamics occurs. General results are out of the scope of this paper, but we deal with several examples corresponding to most of the expected behaviors of the solutions. We first prove a contraction property for general entropies which is a useful tool for uniqueness and for the convergence to some large time asymptotic solutions which may depend on time. Then we focus on power law and logarithmic relative entropies. When the diffusion term is of the type ∇(|x|α∇·), we prove that the inequality relating the entropy with the entropy production term is a Hardy–Poincaré type inequality, that we establish. Here we assume that α ∈ (0,2] and the limit case α = 2 appears as a threshold for the method. As a consequence, we obtain an exponential decay of the relative entropies. In the case of time-periodic coefficients, we prove the existence of a unique time-periodic solution which attracts all other solutions. The case of a degenerate diffusion coefficient taking the form |x|α with α > 2 is also studied. The Gibbs state exhibits a non-integrable singularity. In this case concentration phenomena may occur, but we conjecture that an additional time-dependence restores the smoothness of the asymptotic solution.
Atmospheric Fronts along the East Coast of Taiwan Studied by ERS Synthetic Aperture Radar Images
Authors: Alpers Werner , Chen Jen-Ping , Lin I-I. , Lien Chun-Chi 
Published: March 2007

AbstractThe existence of quasi-stationary alongshore atmospheric fronts typically located 30–70 km off the east coast of Taiwan is demonstrated by analyzing synthetic aperture radar (SAR) images of the sea surface acquired by the European Remote Sensing Satellites ERS-1 and ERS-2. For the data interpretation, cloud images from the Japanese Geostationary Meteorological Satellite GMS-4 and the American Terra satellite, rain-rate maps from ground-based weather radars, sea surface wind data from the scatterometer on board the Quick Scatterometer (QuikSCAT) satellite, and meteorological data from weather maps and radiosonde ascents have also been used. It is shown that these atmospheric fronts are generated by the collisions of the two airflows from opposing directions: one is associated with a weak easterly synoptic-scale wind blowing against the high coastal mountain range at the east coast of Taiwan and the other with a local offshore wind. At the convergence zone where both airflows collide, air is forced to move upward, which often gives rise to the formation of coast-parallel cloud bands. There are two hypotheses about the origin of the offshore wind. The first one is that it is a thermally driven land breeze/katabatic wind, and the second one is that it is wind resulting from recirculated airflow from the synoptic-scale onshore wind. Air blocked by the mountain range at low Froude numbers is recirculated and flows at low levels back offshore. Arguments in favor of and against the two hypotheses are presented. It is argued that both the recirculation of airflow and land breeze/katabatic wind contribute to the formation of the offshore atmospheric front but that land breeze/katabatic wind is probably the main cause.
Resonance in Optimal Perturbation Evolution. Part I: Two-Layer Eady Model
Authors: de Vries H. , Opsteegh J. D. 
Published: March 2007

Abstract
A detailed investigation has been performed of the role of the different growth mechanisms (resonance, potential vorticity unshielding, and normal-mode baroclinic instability) in the evolution of optimal perturbations constructed for a two-layer Eady model and a kinetic energy norm. The two-layer Eady model is obtained by replacing the conventional upper rigid lid by a simple but realistic stratosphere. To make an unambiguous discussion possible, generally applicable techniques have been developed. At the heart of these techniques lies a description of the linear dynamics in terms of a variable number of potential vorticity building blocks (PVBs), which are zonally wavelike, vertically localized sheets of potential vorticity.
If the optimal perturbation is composed of only one PVB, the rapid surface cyclogenesis can be attributed to the growth of the surface PVB (the edge wave), which is excited by the tropospheric PVB via a linear resonance effect. If the optimal perturbation is constructed using multiple PVBs, this simple picture is modified only in the sense that PV unshielding dominates the surface amplification for a short time after initialization. The unshielding mechanism rapidly creates large streamfunction values at the surface, as a result of which the resonance effect is much stronger. A similar resonance effect between the tropospheric PVBs and the tropopause PVB acts negatively on the surface streamfunction amplification. The influence of the stratosphere to the surface development is negligible.
In all cases reported here, the growth due to traditional normal-mode baroclinic instability contributes either negative or only little to the surface development up to the optimization time of two days. It takes at least four days for the flow to become fully dominated by normal-mode growth, thereby confirming that finite-time optimal perturbation growth differs in many aspects fundamentally from asymptotic normal-mode baroclinic instability.
Statistics and Parameterizations of the Effect of Turbulence on the Geometric Collision Kernel of Cloud Droplets
Authors: Franklin Charmaine N. , Vaillancourt Paul A. , Yau M. K. 
Published: March 2007

Abstract
Collision statistics of cloud droplets in turbulent flow have been calculated for 12 droplet size combinations in four flow fields with levels of the eddy dissipation rate of turbulent kinetic energy ranging from 95 to 1535 cm2 s−3. The flow fields were generated by using a direct numerical simulation technique and large numbers of droplets were explicitly tracked through the flow field for each experiment. The effect of turbulence on the collision kernel increases with both increasing radius ratio and eddy dissipation rate. These increases range from fairly modest values to almost 10 times the gravitational geometric collision kernel. The two physical processes responsible for these increases are the radial relative velocities and the preferential concentration or clustering of the droplets. The radial relative velocities increased by up to 3 times the corresponding gravitational value and the greatest increase in the clustering, as measured by the radial distribution function, is 4.5 times the value for a random distribution as for the gravitational case. Parameterizations have been developed for the effect of turbulence on the radial relative velocities and the clustering of the droplets. These models reduce the average root-mean-squared errors in the existing velocity parameterization of Saffman and Turner and Wang et al. by 32% and the clustering parameterization of Zhou et al. by up to 58%.
Multiscale Mountain Waves Influencing a Major Orographic Precipitation Event
Authors: Garvert Matthew F. , Smull Bradley , Mass Cliff 
Published: March 2007

Abstract
This study combines high-resolution mesoscale model simulations and comprehensive airborne Doppler radar observations to identify kinematic structures influencing the production and mesoscale distribution of precipitation and microphysical processes during a period of heavy prefrontal orographic rainfall over the Cascade Mountains of Oregon on 13–14 December 2001 during the second phase of the Improvement of Microphysical Parameterization through Observational Verification Experiment (IMPROVE-2) field program. Airborne-based radar detection of precipitation from well upstream of the Cascades to the lee allows a depiction of terrain-induced wave motions in unprecedented detail.
Two distinct scales of mesoscale wave–like air motions are identified: 1) a vertically propagating mountain wave anchored to the Cascade crest associated with strong midlevel zonal (i.e., cross barrier) flow, and 2) smaller-scale (&lt;20-km horizontal wavelength) undulations over the windward foothills triggered by interaction of the low-level along-barrier flow with multiple ridge–valley corrugations oriented perpendicular to the Cascade crest. These undulations modulate cloud liquid water (CLW) and snow mixing ratios in the fifth-generation Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) Mesoscale Model (MM5), with modeled structures comparing favorably to radar-documented zones of enhanced reflectivity and CLW measured by the NOAA P3 aircraft.
Errors in the model representation of a low-level shear layer and the vertically propagating mountain waves are analyzed through a variety of sensitivity tests, which indicated that the mountain wave’s amplitude and placement are extremely sensitive to the planetary boundary layer (PBL) parameterization being employed. The effects of 1) using unsmoothed versus smoothed terrain and 2) the removal of upstream coastal terrain on the flow and precipitation over the Cascades are evaluated through a series of sensitivity experiments. Inclusion of unsmoothed terrain resulted in net surface precipitation increases of ∼4%–14% over the windward slopes relative to the smoothed-terrain simulation. Small-scale waves (&lt;20-km horizontal wavelength) over the windward slopes significantly impact the horizontal pattern of precipitation and hence quantitative precipitation forecast (QPF) accuracy.
Evaporation and Condensation of Large Droplets in the Presence of Inert Admixtures Containing Soluble Gas
Authors: Elperin T. , Fominykh A. , Krasovitov B. 
Published: March 2007

AbstractIn this study the mutual influence of heat and mass transfer during gas absorption and evaporation or condensation on the surface of a stagnant droplet in the presence of inert admixtures containing noncondensable soluble gas is investigated numerically. The performed analysis is pertinent to slow droplet evaporation or condensation. The system of transient conjugate nonlinear energy and mass conservation equations was solved using anelastic approximation. Using the material balance at the droplet surface the authors obtained equations for Stefan velocity and the rate of change of the droplet radius taking into account the effect of soluble gas absorption at the gas–liquid interface. The authors also derived boundary conditions at gas–liquid interface taking into account the effect of nonisothermal gas absorption. It is demonstrated that the average concentration of the dissolved species in a droplet strongly depends on the relative humidity (RH) for highly soluble and for slightly soluble gaseous atmospheric pollutants. Therewith the difference between the average concentration of the dissolved species in water droplets attains tens of percent for different values of RH.
Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)
Authors: Braslavsky S. E. 
Published: March 2007

AbstractAbstract: The second edition of the Glossary of Terms Used in Photochemistry [Pure Appl. Chem.68, 2223-2286 (1996); <http://www.iupac.org/publications/pac/1996/pdf/6812x2223.pdf>] has been both corrected and updated. Terms have been added related to molecular anisotropy, the use of polarized radiation, nonlinear optical phenomena, and the emerging field of computation of excited species. Some changes have been introduced in this "Glossary" regarding the terms related to radiation energy to make this collection fully compatible with internationally agreed-upon terms. Many links are included to various Web pages listing quantities relevant to the work of photochemists and scientists using photochemical tools.
GH response to ghrelin in subjects with congenital GH deficiency: evidence that ghrelin action requires hypothalamic–pituitary connections
Authors: Maghnie Mohamad , Pennati Maria Cristina , Civardi Elisa , Di Iorgi Natascia , Aimaretti Gianluca , Foschini Maria Loreta , Corneli Ginevra , Tinelli Carmine , Ghigo Ezio , Lorini Renata , Loche Sandro 
Published: March 2007

Objectives: Evaluation of GH response to ghrelin in patients with GH deficiency (GHD) may help to elucidate the site and mechanism of action of ghrelin. We aimed to investigate the GH-releasing effect of ghrelin in children and young adults with childhood-onset GHD.
Design: All subjects underwent ghrelin testing and neuro-imaging examination. Magnetic resonance imaging evidenced the presence of a vascular pituitary stalk (VPS) or its complete absence (PSA).
Patients and methods: Seventeen prepubertal children and nine adult patients with childhood-onset GHD were selected for the study. The children were enrolled at a median age of 5.8 years. The adult subjects were included at a median age of 23.3 years. The diagnosis of GHD in the adult patients had been established at a median age of 8.5 years. Ghrelin was administered at a dose of 1 μg/kg body weight, i.v. at time zero, and blood for GH determination was obtained at 0, 15, 30, 45, 60, 75, 90, 105 and 120 min.
Results: Median GH response after ghrelin was similar between children and adults. Median peak GH response to ghrelin (7.45 μg/l, IQR: 3.9–11.3 μg/l) was significantly higher in patients with VPS (10.9 μg/l, IQR: 2.4–15.1 μg/l) than in those with PSA (IQR: 2.3–6.7 μg/l; P = 0.001). It was significantly higher in subjects with isolated GHD (12.5 μg/l, IQR: 10.8–15.5 μg/l) than in those with multiple pituitary hormone deficiencies (5.15 μg/l, IQR: 2.4–9.0 μg/l; P = 0.003). No correlation was found between the GH peak after ghrelin and body mass index.
Conclusion: The GH response to ghrelin in patients with congenital hypopituitarism depends on the degree of the anatomical abnormalities and lends further support to the assumption that the main action of the peptide is exerted at the hypothalamic level and requires the integrity of hypothalamic–pituitary connections.
Chronic iodine excess does not increase the incidence of hyperthyroidism: a prospective community-based epidemiological survey in China
Authors: Yang Fan , Shan Zhongyan , Teng Xiaochun , Li Yushu , Guan Haixia , Chong Wei , Teng Di , Yu Xiaohui , Fan Chenling , Dai Hong , Yu Yang , Yang Rong , Li Jia , Chen Yanyan , Zhao Dong , Mao Jinyuan , Teng Weiping 
Published: March 2007

Objective: An increasing incidence of hyperthyroidism has been observed when iodine supplementation has been introduced to an iodine-deficient population. Moreover, the influence of chronic more than adequate or excessive iodine intake on the epidemiological features of hyperthyroidism has not been widely and thoroughly described. To investigate the influences of different iodine intake levels on the incidence of hyperthyroidism, we conducted a prospective community-based survey in three communities with mild-deficient, more than adequate (previously mild deficient iodine intake), and excessive iodine intake.
Subjects and methods: In three rural Chinese communities, a total of 3761 unselected inhabitants aged above 13 years participated in the original investigation and 3018 of them received identical examinations after 5 years. Thyroid function, levels of thyroid peroxidase antibody (TPOAb), thyroglobulin antibody and urinary iodine excretion were measured and thyroid ultrasound examination was also performed.
Results: In three communities, median urinary iodine excretion was 88, 214, and 634 μg/l (P<0.05) respectively. The cumulative incidence of hyperthyroidism was 1.4, 0.9, and 0.8% (P>0.05) respectively. Autoimmune hyperthyroidism was predominant in thyroid hyperfunction in all the three cohorts. Either positive TPOAb (>50 U/ml) or goiter in original healthy participants was associated with the occurrence of unsuspected hyperthyroidism in 5 years (logistic regression, OR=4.2 (95% CI 1.7–8.8) for positive TPOAb, OR=3.1 (95% CI 1.4–6.8) for goiter).
Conclusion: Iodine supplementation may not induce an increase in hyperthyroidism in a previously mildly iodine-deficient population. Chronic iodine excess does not apparently increase the risk of autoimmune hyperthyroidism, suggesting that excessive iodine intake may not be an environmental factor involved in the occurrence of autoimmune hyperthyroidism.
Endothelial dysfunction is related to insulin resistance and inflammatory biomarker levels in obese prepubertal children
Authors: Jiménez Miguel Valle , Estepa Rosario Martos , Camacho Rosario MaMorales , Estrada Ramón Cañete , Luna Félix Gascón , Guitarte Francisco Bermudo 
Published: March 2007

Background: The metabolic syndrome (MS) is associated with insulin resistance (IR), a systemic low-grade inflammatory state and endothelial dysfunction. These disorders may arise at a very early age in obese children. This study aimed to investigate the relationship between endothelial dysfunction and both IR and inflammation in prepubertal obese children.
Methods and results: Von Willebrand factor (vWF) and soluble intercellular adhesion molecule-1 (sICAM-1) levels were measured in 46 obese prepubertal children aged 6–9, and in 46 non-obese, age-and sex-matched controls; the possible association of these levels with MS, various inflammatory biomarkers and plasminogen activator inhibitor-1 (PAI-1) was analyzed. Obese children displayed significantly elevated values for sICAM-1 (P = 0.008), vWF (P = 0.034), insulin (P = 0.006), homeostasis model assessment for IR (HOMA-IR; P = 0.003), C-reactive protein (CRP) (P < 0.001), PAI-1 (P = 0.002) and leptin (P < 0.001). Nonsignificant differences were found in interleukin 6 (IL-6) levels. In the obese group, sICAM-1 showed a positive correlation with insulin (P = 0.013), HOMA-IR (P = 0.015), CRP (P = 0.020), IL-6 (P = 0.023) and PAI-1 (P = 0.015). Corrected for age and sex, insulin, HOMA-IR, IL-6 and CPR were found to be independent predictive factors for sICAM-1.
Conclusions: Prepubertal obese children displayed alterations indicative of endothelial dysfunction as well as disorders typical of MS. An association was established between endothelial dysfunction, IR, inflammation and inappropriate fibrinolysis in the children studied.
Adverse Events Associated with High‐Dose Ribavirin: Evidence from the Toronto Outbreak of Severe Acute Respiratory Syndrome
Authors: Muller Matthew P. , Dresser Linda , Raboud Janet , McGeer Allison , Rea Elizabeth , Richardson Susan E. , Mazzulli Tony , Loeb Mark , Louie Marie 
Published: March 2007

Study Objectives. To distinguish adverse events related to ribavirin therapy from those attributable to severe acute respiratory syndrome (SARS), and to determine the rate of potential ribavirin‐related adverse events.Design. Retrospective cohort study.Setting. Hospitals in Toronto, Ontario, Canada.Patients. A cohort of 306 patients with confirmed or probable SARS, 183 of whom received ribavirin and 123 of whom did not, between February 23, 2003, and July 1, 2003. Of the 183 treated patients, 155 (85%) received very high‐dose ribavirin; the other 28 treated patients received lower‐dose regimens.Measurements and Main Results. Data on all patients with SARS admitted to hospitals in Toronto were abstracted from charts and electronic databases onto a standardized form by trained research nurses. Logistic regression was used to evaluate the association between ribavirin use and each adverse event (progressive anemia, hypomagnesemia, hypocalcemia, bradycardia, transaminitis, and hyperamylasemia) after adjusting for SARS‐related prognostic factors and corticosteroid use. In the primary logistic regression analysis, ribavirin use was strongly associated with anemia (odds ratio [OR] 3.0, 99% confidence interval [CI] 1.5–6.1, p<0.0001), hypomagnesemia (OR 21, 99% CI 5.8–73, p<0.0001), and bradycardia (OR 2.3, 99% CI 1.0–5.1, p=0.007). Hypocalcemia, transaminitis, and hyperamylasemia were not associated with ribavirin use. The risk of anemia, hypomagnesemia, and bradycardia attributable to ribavirin use was 27%, 45%, and 17%, respectively.Conclusions. High‐dose ribavirin is associated with a high rate of adverse events. The use of high‐dose ribavirin is appropriate only for the treatment of infectious diseases for which ribavirin has proven clinical efficacy, or in the context of a clinical trial. Ribavirin should not be used empirically for the treatment of viral syndromes of unknown origin.