bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Role of Deformation and Potential Vorticity in Southern Hemisphere Blocking Onsets
Authors: Dong Li , Colucci Stephen J. 
Published: November 2005

Abstract
The relative importance of interactions between deformation and potential vorticity (PV) as a block-onset mechanism is examined in 30 cases of atmospheric blocking over the Southern Hemisphere (SH). The blocking cases are diagnosed with a quasigeostrophic model for the u component of the geostrophic wind tendency. In this model, two mechanisms, the advection of the meridional gradient of PV and interactions between deformation and PV, can force the weakening of westerly flow or increasing easterly flow associated with blocking. The first forcing mechanism, which does not directly include deformation, indicates that the advection of equatorward increasing cyclonic PV (or equatorward decreasing anticyclonic PV) could force a local weakening of geostrophic westerlies or increasing easterlies. The second forcing mechanism, which represents the net effect of interactions between deformation and PV, indicates that eastward increasing PV embedded in a cyclonically sheared flow or equatorward increasing PV coincident with a stretching (diffluent) flow could each force a weakening in the westerlies.
While deformation is a distinct signature of blocking, it may not always actively participate in the formation of blocking. Advection and interaction contributions generally opposed each other in both the diagnosed blocking and nonblocking cases. Weakening westerlies associated with block onset would occur when one effect (usually the advection effect) contributes more negatively to the wind tendency than the opposing, positive contribution from the other effect. When deformation is actively involved in the formation of blocking, self-interactions between synoptic-scale PV and deformation and self-interactions between planetary-scale PV and deformation contribute more importantly than synoptic-to-planetary-scale interactions between PV and deformation fields to the weakening of westerlies associated with block onsets.
Stirring and Mixing in Two-Dimensional Divergent Flow
Authors: Lukovich Jennifer Verlaine , Shepherd Theodore G. 
Published: November 2005

AbstractWhile stirring and mixing properties in the stratosphere are reasonably well understood in the context of balanced (slow) dynamics, as is evidenced in numerous studies of chaotic advection, the strongly enhanced presence of high-frequency gravity waves in the mesosphere gives rise to a significant unbalanced (fast) component to the flow. The present investigation analyses result from two idealized shallow-water numerical simulations representative of stratospheric and mesospheric dynamics on a quasi-horizontal isentropic surface. A generalization of the Hua–Klein Eulerian diagnostic to divergent flow reveals that velocity gradients are strongly influenced by the unbalanced component of the flow. The Lagrangian diagnostic of patchiness nevertheless demonstrates the persistence of coherent features in the zonal component of the flow, in contrast to the destruction of coherent features in the meridional component. Single-particle statistics demonstrate t2 scaling for both the stratospheric and mesospheric regimes in the case of zonal dispersion, and distinctive scaling laws for the two regimes in the case of meridional dispersion. This is in contrast to two-particle statistics, which in the mesospheric (unbalanced) regime demonstrate a more rapid approach to Richardson’s t3 law in the case of zonal dispersion and is evidence of enhanced meridional dispersion.
A Barotropic Envelope Rossby Soliton Model for Block–Eddy Interaction. Part IV: Block Activity and Its Linkage with a Sheared Environment
Authors: Luo Dehai 
Published: November 2005

Abstract
In this paper, a basic-state flow that has a linear, weak meridional shear is used as a mean flow condition to see if the blocking activity is related to the state of the zonal mean flow based upon the envelope soliton theory proposed in Part I. It is found that an isolated coherent structure similar to a dipole block can arise from the resonant interaction between preexisting planetary- and synoptic-scale waves, but its asymmetry, intensity, and persistence depend strongly upon the horizontal shear of the basic-state flow prior to block onset. The cyclonic shear of the basic-state flow not only plays an important role in preventing the eastward spread of block energy, but also provides a strong diffluent flow as a precursor of block flow. In such an environment, a high amplitude dipole anomaly is maintained and the deformed synoptic-scale eddies tend to deflect northward. But the anticyclonic shear of a basic-state flow plays a reverse role, which causes deformed eddies to deflect southward.
It is also found that positive westerly wind anomalies at both high and low latitudes and negative anomalies at middle latitudes are maintained by synoptic-scale eddies through the self-interaction of block. In this case, the zonal mean westerly wind is accelerated at high and low latitudes, and decelerated at middle latitudes. Only for a basic state with cyclonic shear is the meridional profile of the zonal mean wind during the onset of a dipole block in agreement with observations.
In addition, it can be shown by computing scatter diagrams of potential vorticity against streamfunction in different sheared environments that an eddy-induced isolated block can exhibit a local free-mode characteristic. Two approximately linear functional relationships between potential vorticity and streamfunction are found to be probably attributed to synoptic eddies.
Large-Scale Modes in a Rotating Atmosphere with Radiative–Convective Instability and WISHE
Authors: Fuchs Zeljka , Raymond David J. 
Published: November 2005

Abstract
A highly simplified parameterization of diabatic processes is applied to linearized equations on a equatorial beta plane. The diabatic processes include moist convection, cloud–radiation interactions (CRI), and wind-induced surface heat exchange (WISHE). The precipitation rate is assumed to increase linearly as the vertically averaged saturation deficit decreases.
The modeled modes are Matsuno’s normal modes, that is, Kelvin waves, mixed Rossby–gravity waves, Rossby waves, and inertio–gravity waves, and an additional mode called here a slow moisture mode. All of the Matsuno modes are damped and remain stable even when CRI and WISHE are turned on. Their phase speeds do not vary much from Matsuno’s adiabatic values except for very long wavelength Kelvin and Rossby modes, for which the phase speeds are reduced compared to the adiabatic values. The slow moisture modes are stationary and unstable under CRI, while WISHE causes them to propagate. Under CRI and WISHE together the slow moisture modes are unstable and eastward propagating for long wavelengths and slowly moving relative to the mean flow for short wavelengths. The dispersion relations of the slow moisture modes are one of nearly constant or decreasing frequency with increasing wavenumber. The most important model parameter is the tropospheric moisture relaxation time scale, which is chosen to be 1 day.
The model failed to explain the observed phase speeds of convectively coupled Matsuno modes. Following Mapes, the authors suggest that other dynamics, more realistic than the one including only the first baroclinic mode, may be responsible for these modes.
Momentum Flux Spectrum of Convectively Forced Gravity Waves: Can Diabatic Forcing Be a Proxy for Convective Forcing?
Authors: Chun Hye-Yeong , Song In-Sun , Horinouchi Takeshi 
Published: November 2005

Abstract
The momentum flux of convectively forced internal gravity waves is calculated using explicitly resolved model-simulated gravity wave data. The momentum flux in a control simulation with nonlinearity and cloud microphysical processes is compared with that in quasi-linear dry simulations with either diabatic forcing or nonlinear forcing. It is found that the momentum flux induced by either of these two sources is significantly different from each other and also from the momentum flux in the control simulation. This is because the spectral distribution and magnitude of each wave source are significantly different and the cancellation of the momentum flux by cross-correlation terms between the two sources cannot be included in the momentum flux by a single source. This suggests that a parameterization of convectively forced gravity waves must take into account nonlinear forcing as well as diabatic forcing in order to qualitatively and quantitatively represent the reference-level momentum flux spectrum.
Principal Component Analysis of Doppler Radar Data. Part I: Geometric Connections between Eigenvectors and the Core Region of Atmospheric Vortices
Authors: Harasti Paul R. , List Roland 
Published: November 2005

Abstract
This is the first in a three-part series of papers that present the first applications of principal component analysis (PCA) to Doppler radar data. Although this novel approach has potential applications to many types of atmospheric phenomena, the specific goal of this series is to describe and verify a methodology that establishes the position and radial extent of the core region of atmospheric vortices. The underlying assumption in the current application is that the streamlines of the nondivergent component of the horizontal wind are predominantly circular, which is a characteristic often observed in intense vortices such as tropical cyclones.
The method employs an S2-mode PCA on the Doppler velocity data taken from a single surveillance scan and arranged sequentially in a matrix according to the range and azimuth coordinates. Part I begins the series by examining the eigenvectors obtained from such a PCA applied to a Doppler velocity model for a modified, Rankine-combined vortex, where the ratio of the radius of maximum wind to the range from the radar to the circulation center is varied over a wide range of values typically encountered in the field. Results show that the first two eigenvectors within the eigenspace of range coordinates represent over 99% of the total variance in the data. It is also demonstrated that the coordinates of particular cusps in the curves of the eigenvector coefficients plotted against their indices are geometrically related to both the position of circulation center and the radius of maximum wind.
Venous Thrombosis: The Role of Genes, Environment, and Behavior
Authors: Rosendaal Frits R. 
Published: November 2005

Over the last decade we have witnessed an avalanche of newly identified risk factors for venous thrombosis. This has advanced our knowledge of its etiology, because more determinants have been described and because the underlying concepts have received a new and broader understanding.
Venous thrombosis is a common multicausal disease occurring as the result of interacting genetic, environmental and behavioral risk factors. Some of these have been known since medieval times, such as the increased risk of thrombosis during immobilization in pregnancy and after childbirth (although retained milk of the breast-feeding mother was seen as the primary cause for the latter). Pregnancy and puerperium still cause thrombosis, as do exogenous hormones in oral contraceptives and hormonal replacement therapy. Furthermore, the immobilization in the puerperium of the old days translates directly to situations of immobilization in current times, such as prolonged travel in airplanes or excessive electronic gaming.
While pedigrees with abundant thrombosis were observed in the early 1900s, the first cause of heritable thrombophilia (antithrombin deficiency) was discovered in 1965, with the subsequent identification of deficiencies of protein C and protein S in the early 1980s. These were uncommon and strong risk factors, whereas the more recently discovered genetic variants are common and weak, and cause disease only in the presence of other factors.
A Unique Activating Mutation in JAK2 (V617F) Is at the Origin of Polycythemia Vera and Allows a New Classification of Myeloproliferative Diseases
Authors: Vainchenker William , Constantinescu Stefan N. 
Published: November 2005

Abstract
Myeloproliferative disorders (MPDs) are heterogeneous diseases that occur at the level of a multipotent hematopoietic stem cell. They are characterized by increased blood cell production related to cytokine hypersensitivity and virtually normal cell maturation. The molecular pathogenesis of the MPDs has been poorly understood, except for chronic myeloid leukemia (CML), where the Bcr-Abl fusion protein exhibits constitutive kinase activity. Since some rare MPDs are also related to a dysregulated kinase activity, a similar mechanism was thought to be likely responsible for the more frequent MPDs. We investigated the mechanisms of endogenous erythroid colony formation (EEC) by polycythemia vera (PV) erythroid progenitor cells and found that EEC formation was abolished by a pharmacological inhibitor of JAK2 as well as an siRNA against JAK2. JAK2 sequencing revealed a unique mutation in the JH2 domain leading to a V617F substitution in more than 80% of the PV samples. This mutation in the pseudokinase autoinhibitory domain results in constitutive kinase activity and induces cytokine hypersensitivity or independence of factor-dependent cell lines. Retroviral transduction of the mutant JAK2 into murine HSC leads to the development of an MPD with polycythemia. The same mutation was found in about 50% of patients with idiopathic myelofibrosis (IMF) and 30% of patients with essential thrombocythemia (ET). Using different approaches, four other teams have obtained similar results. The identification of the JAK2 mutation represents a major advance in our understanding of the molecular pathogenesis of MPDs that will likely permit a new classification of these diseases and the development of novel therapeutic approaches.
POEMS Syndrome
Authors: Dispenzieri Angela 
Published: November 2005

Abstract
POEMS syndrome is defined by the presence of a peripheral neuropathy (P), a monoclonal plasma cell disorder (M), and other paraneoplastic features, the most common of which include organomegaly (O), endocrinopathy (E), skin changes (S), papilledema, edema, effusions, ascites, and thrombocytosis. Virtually all patients will have either sclerotic bone lesion(s) or co-existent Castleman’s disease. Not all features of the disease are required to make the diagnosis, and early recognition is important to reduce morbidity. Other names for the syndrome include osteosclerotic myeloma, Crow-Fukase syndrome, or Takatsuki syndrome. Because the peripheral neuropathy is frequently the overriding symptom and because the characteristics of the neuropathy are similar to that chronic inflammatory demyelinating polyneuropathy (CIDP), patients are frequently misdiagnosed with CIDP or monoclonal gammopathy of underdetermined significance (MGUS)-associated peripheral neuropathy. Not until additional features of the POEMS syndrome are recognized is the correct diagnosis made and effective therapies initiated. Clues to an early diagnosis include thrombocytosis and sclerotic bone lesions on plain skeletal radiographs. Therapies that may be effective in patients with CIDP and MGUS-associated peripheral neuropathy (intravenous gammaglobulin and plasmapheresis) are not effective in patients with POEMS. Instead, the mainstays of therapy for patients with POEMS include irradiation, corticosteroids, and alkylator-based therapy, including high-dose chemotherapy with peripheral blood stem cell transplantation.
Fetal Globin Induction—Can It Cure β Thalassemia?
Authors: Perrine Susan P. 
Published: November 2005

Abstract
The β thalassemias are one of a few medical conditions in which reactivation of a gene product that is expressed during fetal life can functionally replace a deficiency of essential proteins expressed at a later developmental stage. The fetal globin genes are present and normally integrated in hematopoietic stem cells, and at least one fetal gene appears accessible for reactivation, particularly in β° thalassemia. However, rapid cellular apoptosis from α globin chain precipitation, and relatively low levels of endogenous erythropoietin (EPO) in some β+ thalassemia patients contribute to the anemia in β thalassemia syndromes.
In clinical trials, three classes of therapeutics have demonstrated proof-of-principle of this approach by raising total hemoglobin levels by 1–4 g/dL above baseline in thalassemia patients: EPO preparations, short chain fatty acid derivatives (SCFADs), and chemotherapeutic agents. Although thalassemic erythrocytes survive only for a few days, the magnitude of these responses is similar to those induced by rhu-EPO in anemic conditions of normal erythrocyte survival. New oral therapeutic candidates, which stimulate both fetal globin gene expression and erythropoiesis, and combinations of therapeutics with complementary molecular actions now make this gene-reactivation approach feasible to produce transfusion independence in many patients. Development of the candidate therapeutics is hindered largely by costs of drug development for an orphan patient population.
Inherited Risk Factors for Venous Thrombosis
Authors: Cushman Mary 
Published: November 2005

Abstract
Venous thrombosis occurs as a consequence of genetic and environmental risk factors. Since the discovery of factor V Leiden, the most common genetic risk factor, there has been intense interest in clarifying the roles of genes and the environment with thrombosis risk. The translation of this risk information to clinical practice is a challenging one in the setting of a rapidly expanding knowledge base that includes application of genetic medicine. There are benefits, but also potential harms, of testing for inherited disorders associated with thrombosis. This paper reviews inherited risk factors for thrombosis and discuss clinical applications of testing.
Protective effect of leptin against ischemia-reperfusion injury in the rat small intestine
Authors: Hacioglu Alper , Algin Cem , Pasaoglu Ozgul , Pasaoglu Ercument , Kanbak Gungor 
Published: November 2005

AbstractBackgroundThe small intestine is extremely sensitive to ischemia-reperfusion (I/R) injury and a range of microcirculatory disturbances which contribute to tissue damage. Previous studies have shown that leptin plays an important physiological role in the microvasculature. The aim of this study was to evaluate the protective effects of leptin in I/R – induced mucosal injury in the small intestine.MethodsForty rats were divided into 5 groups (n = 8). Group I was subjected to a sham operation. Following mesenteric ischemia in group II (control); physiologic saline 1 cm3, in group III; leptin 100 μg/kg, and physiologic saline 1 cm3, in group IV;NG-L-arginine methyl ester (L-NAME) 20 mg/kg, and physiologic saline 1 cm3, in group V; leptin 100 μg/kg, L-NAME 20 mg/kg, and physiologic saline 1 cm3were given intra-peritoneally. In these groups, an I/R procedure was performed by occlusion of the superior mesenteric artery for 45 min followed by 120 min reperfusion. After reperfusion, the small intestines were resected for malondialdehyde (MDA) and nitric oxide (NO) concentration and histopathologic properties. Mucosal lesions were scored between 0 and 5. Tissue MDA and NO concentration and histopathologic grades were compared statistically.ResultsTissue MDA level significantly increased (P< 0.05), tissue NO level significantly decreased in group V animals, compared to group III animals respectively (P< 0.001). Histopathologically, intestinal injury significantly decreased in the leptin treated ischemic group.ConclusionLeptin can be used safely in mesenteric occlusive diseases, since it induces NO formation and release in mesenteric vessels.
Opportunistic screening for iron-deficiency in 6–36 month old children presenting to the paediatric emergency department
Authors: Pusic Martin V , Dawyduk Brenda J , Mitchell David 
Published: November 2005

AbstractBackgroundThe Complete Blood Count (CBC) is a test frequently performed on children presenting to the Pediatric Emergency Department (PED), usually for the evaluation of an infectious illness. The CBC also allows for screening for Iron-deficiency Anemia. This study aims to determine the prevalence of a low Mean Cell Volume (MCV) in children having a CBC performed during a PED visit and whether physicians acted upon the abnormal value.MethodsWe present a retrospective cohort study. We reviewed the PED charts of all children 6–36 months of age who had a CBC performed during a 4-month period and the red blood cell mean cell volume was low. Our main outcome variable was whether or not the possible iron deficiency was addressed through documentation of either iron therapy or further investigation.Results938 children had a CBC performed during the two periods. Of these, 78 (8%) had an abnormal MCV or Hemoglobin with no previously identified explanation. Physicians documented either treatment or follow-up investigations in 27 cases (35%, 95% CI: 24–46%). Factors associated with the physician documenting either treatment or investigation plan were the following: hemoglobin level (OR 12.6; 95%CI: 4.0, 39) and age ≤ 18 months (OR 4.2; 95%CI: 1.4, 13).ConclusionChildren who have had a CBC in the PED can be screened for iron deficiency at no additional cost. Physicians may be under-utilizing this information.
Evaluating changeability to improve fruit and vegetable intake among school aged children
Authors: Nanney Marilyn S , Haire-Joshu Debra , Elliott Michael , Hessler Kimberly , Brownson Ross C 
Published: November 2005

Abstract

Background
The purposes of this paper are two fold. First, to describe an approach used to identify fruits and vegetables to target for a child focused dietary change intervention. Second, to evaluate the concept of fruit and vegetable changeability and feasibility of applying it in a community setting.

Methods
Steps for identifying changeable fruits and vegetables include (1) identifying a dietary database (2) defining geographic and (3) personal demographics that characterize the food environment and (4) determining which fruits and vegetables are likely to improve during an intervention. The validity of these methods are evaluated for credibility using data collected from quasi-experimental, controlled design among 7–9 year old children (n = 304) participating in a tutoring or mentoring program in St. Louis, MO. Using a 28-item food frequency questionnaire, parents were asked to recall for their child how often foods were eaten the past 7 days. This questionnaire was repeated eight months later (response rate 84%). T-test analyses are used to determine mean serving differences from baseline to post test.

Results
The mean serving differences from baseline to post test were significant for moderately eaten fruits (p < .001), however, not for vegetables (p = .312). Among the intervention group, significantly more children ate grapes (p < .001), peaches (p = .022), cantaloupe (p < .001), and spinach (p = .044) at post testing – all identified as changeable with information tailored to participants.

Conclusion
Data driven, food focused interventions directed at a priority population are feasible and practical. An empirical evaluation of the assumptions associated with these methods supports this novel approach. However, results may indicate that these methods may be more relevant to fruits than vegetables. This process can be applied to diverse populations for many dietary outcomes. Intervention strategies that target only those changeable fruits and vegetables are innovative and warrant further study.