bluuebunny/crossref_metadata_2025 huggingface dataset:
Origin of pingo‐like features on the Beaufort Sea shelf and their possible relationship to decomposing methane gas hydrates
Authors: Paull Charles K. , Ussler William , Dallimore Scott R. , Blasco Steve M. , Lorenson Thomas D. , Melling Humfrey , Medioli Barbara E. , Nixon F. Mark , McLaughlin Fiona A.
Published: January 2007

The Arctic shelf is currently undergoing dramatic thermal changes caused by the continued warming associated with Holocene sea level rise. During this transgression, comparatively warm waters have flooded over cold permafrost areas of the Arctic Shelf. A thermal pulse of more than 10°C is still propagating down into the submerged sediment and may be decomposing gas hydrate as well as permafrost. A search for gas venting on the Arctic seafloor focused on pingo‐like‐features (PLFs) on the Beaufort Sea Shelf because they may be a direct consequence of gas hydrate decomposition at depth. Vibracores collected from eight PLFs had systematically elevated methane concentrations. ROV observations revealed streams of methane‐rich gas bubbles coming from the crests of PLFs. We offer a scenario of how PLFs may be growing offshore as a result of gas pressure associated with gas hydrate decomposition.
Contactless electroreflectance of GaInNAsSb∕GaAs single quantum wells with indium content of 8%–32%
Authors: Kudrawiec R. , Yuen H. B. , Motyka M. , Gladysiewicz M. , Misiewicz J. , Bank S. R. , Bae H. P. , Wistey M. A. , Harris James S.
Published: January 2007

Interband transitions in GaInNAsSb∕GaAs single quantum wells (SQWs) with nominally identical nitrogen and antimony concentrations (2.5% N and 7% Sb) and varying indium concentrations (from 8% to 32%) have been investigated by contactless electroreflectance (CER). CER features related to optical transitions between the ground and excited states have been clearly observed. Energies of the QW transitions extracted from CER measurements have been matched with those obtained from theoretical calculations performed within the effective mass approximation for various conduction-band offsets (QC) and various electron effective masses. It has been found that the QC increases from 40% to 80% with the rise of the indium content from 8% to 32% and the electron effective mass is close to 0.09m0. The results show that the band gap discontinuity in GaInNAsSb∕GaAs SQWs can be broadly tuned with a change in the indium concentration.
Influence of working pressure on properties of titanium oxide thin films at room temperature
Authors: Zhao Z. W. , Tay B. K.
Published: January 2007

Titanium oxide thin films were deposited by off-plane filtered cathodic vacuum arc (FCVA) at room temperature as a function of working pressure. The deposition rate decreases with working pressure. The deposited films are amorphous with low residual stress (less than 0.5GPa) and smooth surface. The film transmittance increases with the increase of working pressure, while the refractive index and extinction coefficient both decrease. Similar behaviors of film properties (e.g., deposition rate and optical properties) are also found in other metal oxides by FCVA, such as zirconium oxide and aluminium oxide. Common features observed in various metal oxides are explained by a model based on ion-gas interactions. The feasibility of these metal oxide thin films as optical coatings is also discussed.
Relativistic coupled-cluster calculations of parity nonconservation in Ba+ by the sum-over-states approach
Authors: Gopakumar Geetha , Das Bhanu Pratap , Chaudhuri R. K. , Mukherjee D. , Hirao K.
Published: January 2007

The authors present the results of their calculation for the parity nonconserving 5p66s1∕2→5p65d3∕2 transition in Ba+ using the relativistic coupled-cluster theory in the singles, doubles, and partial triples approximation. The contributions from the leading intermediate states are explicitly considered. It is found that the largest contribution comes from the ∣5p66p1∕2⟩ state. Their results are in reasonable agreement with other calculations.
Quasianamorphic optical imaging system with tomographic reconstruction for electron beam imaging
Authors: Bender H. , Carlson C. , Frayer D. , Johnson D. , Jones K. , Meidinger A. , Ekdahl C.
Published: January 2007

We have developed a quasianamorphic optical tomography system coupled to a streak camera to provide continuous recording of the electron beam profile of an intense, long-pulse induction accelerator. A tomographic reconstruction method based on a maximum-entropy algorithm is used to reconstruct the images. The system has simplified the calculation of beam moments, eliminated ambiguity due to beam motion, and contributed to accelerator tuning.
Aggregation of β-amyloid fragments
Authors: Meinke Jan H. , Hansmann Ulrich H. E.
Published: January 2007

The authors study the folding and aggregation of six chains of the β-amyloid fragment 16–22 using Monte Carlo simulations. While the isolated fragment prefers a helical form at room temperature, in the system of six interacting fragments one observes both parallel and antiparallel β sheets below a crossover temperature Tx≈420K. The antiparallel sheets have lower energy and are therefore more stable. Above the nucleation temperature the aggregate quickly dissolves into widely separated, weakly interacting chains.
High throughput spectrometer for fast localized Doppler measurements
Authors: Craig D. , Den Hartog D. J. , Ennis D. A. , Gangadhara S. , Holly D.
Published: January 2007

A new custom-built duo spectrometer has been commissioned for fast localized Doppler measurements of plasma ions in the Madison Symmetric Torus. The instrument combines very high optical throughput (transmission efficiency of 6% and etendue of 0.80mm2sr divided into two simultaneous measurements) with good resolution (λ∕Δλ=5600). The design is a double grating variant of the Czerny-Turner layout and has been carefully optimized for fast (100kHz) measurements of the CVI line at 343.4nm. The instrument is currently being applied for high speed charge exchange recombination spectroscopy measurements.
Wire tomography in the H-1NF heliac for investigation of fine structure of magnetic islands
Authors: Kumar Santhosh T. A. , Blackwell Boyd D. , Harris Jeffrey H.
Published: January 2007

Electron beam wire tomography in the H-1NF heliac enables high resolution mapping of vacuum flux surfaces with minimal disruption of the plasma operations schedule. Recent experimental results have proven this technique to be a highly accurate and high resolution method for mapping vacuum magnetic islands. Islands of width as small as δ∼8mm have been measured, providing estimates of the internal rotational transform of the island. Point-to-point comparison of the mapping results with computer tracing, in conjunction with an image warping technique, enables systematic exploration of magnetic islands and surfaces of interest. Recent development of a fast mapping technique significantly reduced the mapping time and made this technique suitable for mapping at higher magnetic fields. This article presents recent experimental results and associated techniques.
Integral equation theory study on the structure and effective interactions in star polymer nanocomposite melts
Authors: Zhao Lei , Li Yi-Gui , Zhong Chongli
Published: January 2007

The polymer reference interaction site model theory is used to investigate the radial distribution function, potential of mean force, depletion force, and second virial coefficient in star polymer nanocomposite melts. The contact aggregation of nanoparticles for relatively weak nanoparticle-monomer attraction and the bridging aggregation of nanoparticles for very large nanoparticle-monomer attraction are observed. The star architecture can well suppress the organization states of direct contact and bridging structure for the moderate nanoparticle-monomer attraction, and promote the bridging-type organization for relatively large nanoparticle-monomer attraction. At constant particle volume fraction, the arm length quantitatively affects the organization states of star polymer nanocomposite melt, and larger repulsive barriers are existent to prevent the contact aggregation of larger nanoparticles. These observations provide useful information for the development of new nanocomposite materials.
A thermochemically competitive local hybrid functional without gradient corrections
Authors: Bahmann Hilke , Rodenberg Alexander , Arbuznikov Alexei V. , Kaupp Martin
Published: January 2007

Following the suggestion of local hybrid functionals with position-dependent exact-exchange admixture [J. Jaramillo, G. E. Scuseria, and M. Ernzerhof, J. Chem. Phys. 118, 1068 (2003)], a functional that mixes only local and exact exchange plus local correlation has been constructed. With a simple local mixing function for the position dependence, this Lh-SVWN functional provides atomization energies for the G2-1 set that are competitive with currently available state-of-the-art functionals like, e.g., B3LYP. This is achieved without generalized gradient approximations for exchange or correlation.
Hypersonic acoustic excitations in binary colloidal crystals: Big versus small hard sphere control
Authors: Tommaseo G. , Petekidis G. , Steffen W. , Fytas G. , Schofield A. B. , Stefanou N.
Published: January 2007

The phononic band structure of two binary colloidal crystals, at hypersonic frequencies, is studied by means of Brillouin light scattering and analyzed in conjunction with corresponding dispersion diagrams of the single colloidal crystals of the constituent particles. Besides the acoustic band of the average medium, the authors’ results show the existence of narrow bands originating from resonant multipole modes of the individual particles as well as Bragg-type modes due to the (short-range) periodicity. Strong interaction, leading to the occurrence of hybridization gaps, is observed between the acoustic band and the band of quadrupole modes of the particles that occupy the largest fractional volume of the mixed crystal; the effective radius is either that of the large (in the symmetric NaCl-type crystalline phase) or the small (in the asymmetric NaZn13-type crystalline phase) particles. The possibility to reveal a universal behavior of the phononic band structure for different single and binary colloidal crystalline suspensions, by representing in the dispersion diagrams reduced quantities using an appropriate length scale, is discussed.
Is arterial stiffening in Alström syndrome linked to the development of cardiomyopathy?
Authors: Smith J. C. , McDonnell B. , Retallick C. , McEniery C. , Carey C. , Davies J. S. , Barrett T. , Cockcroft J. R. , Paisey R.
Published: January 2007

Background  Alström syndrome (AS) is a rare autosomal recessive condition characterized by retinal degeneration, childhood obesity, and severe insulin resistance. Dilated cardiomyopathy of unknown aetiology is a well‐recognized and potentially lethal complication. The aim of this study was to investigate the relationship between vascular function, hyperinsulinaemia and cardiac performance in AS.

Materials and methods  Fifteen subjects with AS (mean age 21 years, range 10–35) were studied and compared with age‐, sex‐, and blood pressure‐matched healthy controls. Large artery stiffness and wave reflections were assessed in both groups by measuring aortic and brachial pulse wave velocity (PWV) (carotid‐femoral and carotid‐radial) and augmentation index (AIX) (Sphygmocor). In AS subjects, left ventricular function was assessed by echocardiography and metabolic parameters including fasting insulin, glucose, lipids and brain natriuretic peptide were also measured.

Results  Comparing AS subjects vs. controls (mean ± SD), AIX was elevated in AS subjects (18 ± 9% vs. 3 ± 11%, P < 0·0001). No significant changes in brachial PWV (8·1 ± 1·3 m s−1 vs. 7·3 ± 1·1 m s−1, P = 0·14) or aortic PWV (6·5 ± 1·1 m s−1 vs. 6·0 ± 1·0 m s−1, P = 0·26) were observed. AS subjects were hyperinsulinaemic and had disturbances in lipid profiles relative to controls. No correlations were observed between vascular, metabolic and echocardiographic parameters.

Conclusions  In AS there are alterations in the shape of the central arterial pressure waveform associated with augmented aortic systolic pressure and indicative of increased wave reflection. Unfavourable central arterial haemodynamics in AS may contribute to the development of cardiomyopathy but other aetiological factors are probably involved.
Subcellular multitasking – multiple destinations and roles for the Plasmodium falcilysin protease
Authors: Ralph Stuart A.
Published: January 2007

The Plasmodium falcilysin protease is a M16‐family protease that has been previously identified as a food vacuole enzyme that participates in the breakdown of haemoglobin. Plant homologues of this protease are responsible for breaking down transit peptides that have been processed in mitochondria and plastids, and in this issue of Molecular Microbiology, Ponpuak and colleagues show that falcilysin participates in degradation of transit peptides and haemoglobin in discrete subcellular organelles. The recruitment of a gene product from one cellular compartment to another is a recurring phenomenon in molecular evolutionary biology, and arises through a number of distinct mechanisms. Plasmodium accomplishes this triple act by targeting products of the single falcilysin gene to multiple compartments.
Clarity of Responsibility and Corruption
Authors: Tavits Margit
Published: January 2007

This article demonstrates that political institutions influence the level of corruption via clarity of responsibility. The key hypothesis is that when political institutions provide high clarity of responsibility, politicians face incentives to pursue good policies and reduce corruption. These incentives are induced by the electorates' rejection of incumbents who do not provide satisfactory outcomes. However, if lines of responsibility are not clear, the ability of voters to evaluate and punish politicians—as well as to create incentives for performance—declines. The findings confirm that countries with institutions that allow for greater clarity of responsibility have lower levels of corruption.
Breathing dysfunctions associated with impaired control of postinspiratory activity in Mecp2−/y knockout mice
Authors: Stettner Georg M. , Huppke Peter , Brendel Cornelia , Richter Diethelm W. , Gärtner Jutta , Dutschmann Mathias
Published: January 2007

Rett syndrome (RTT) is an inborn neurodevelopmental disorder caused by mutations in the X‐linked methyl‐CpG binding protein 2 gene (MECP2). Besides mental retardation, most patients suffer from potentially life‐threatening breathing arrhythmia. To study its pathophysiology, we performed comparative analyses of the breathing phenotype of Mecp2−/y knockout (KO) and C57BL/6J wild‐type mice using the perfused working heart–brainstem preparation (WHBP). We simultaneously recorded phrenic and efferent vagal nerve activities to analyse the motor pattern of respiration, discriminating between inspiration, postinspiration and late expiration. Our results revealed respiratory disturbances in KO preparations that were similar to those reported from in vivo measurements in KO mice and also to those seen in RTT patients. The main finding was a highly variable postinspiratory activity in KO mice that correlated closely with breathing arrhythmias leading to repetitive apnoeas even under undisturbed control conditions. Analysis of the pontine and peripheral sensory regulation of postinspiratory activity in KO preparations revealed: (i) prolonged apnoeas associated with enhanced postinspiratory activity after glutamate‐induced activation of the pontine Kölliker‐Fuse nucleus; and (ii) prolonged apnoeas and lack of reflex desensitization in response to repetitive vagal stimulations. We conclude that impaired network and sensory mediated synaptic control of postinspiration induces severe breathing dysfunctions in Mecp2−/y KO preparations. As postinspiration is particularly important for the control of laryngeal adductors, the finding might explain the upper airway‐related clinical problems of patients with RTT such as apnoeas, loss of speech and weak coordination of breathing and swallowing.
Maternal taurine supplementation in the late pregnant rat stimulates postnatal growth and induces obesity and insulin resistance in adult offspring
Authors: Hultman Karin , Alexanderson Camilla , Mannerås Louise , Sandberg Mats , Holmäng Agneta , Jansson Thomas
Published: January 2007

An adequate supply of taurine during fetal life is important for normal beta‐cell development and insulin action. An altered availability of taurine may programme glucose metabolism in utero and result in type 2 diabetes in adult age. We examined whether maternal taurine supplementation in late pregnant rats affects postnatal growth, adult body composition, insulin sensitivity and endogenous insulin secretion in intrauterine growth restricted (IUGR) and normal offspring. Uterine artery ligation or sham operations were performed on gestational day (GD) 19. Taurine supplementation was given to half of the dams from GD 18 until term, resulting in four groups of offspring: sham (n= 22), sham/taurine (n= 22), IUGR (n= 22) and IUGR/taurine (n= 24). The offspring were studied at 12 weeks of age. In offspring with normal birth weight, fetal taurine supplementation markedly stimulated postnatal growth. In sham/taurine females, fat depots, plasma free fatty acid and leptin concentrations were increased, and insulin sensitivity was reduced. Insulin sensitivity was unaltered in IUGR and IUGR/taurine offspring. However, whereas IUGR offspring showed little catch‐up growth, 50% of IUGR/taurine animals displayed complete catch‐up at 12 weeks of age, and these animals had increased fat depots and reduced insulin sensitivity. In conclusion, taurine supplementation in late gestation resulted in accelerated postnatal growth, which was associated with adult obesity and insulin resistance in both IUGR and normal offspring. This effect was particularly evident in females. These data suggest that fetal taurine availability is an important determinant for postnatal growth, insulin sensitivity and fat accumulation.
Atom Interferometer Measurement of the Newtonian Constant of Gravity
Authors: Fixler J. B. , Foster G. T. , McGuirk J. M. , Kasevich M. A.
Published: January 2007

We measured the Newtonian constant of gravity,
G
, using a gravity gradiometer based on atom interferometry. The gradiometer measures the differential acceleration of two samples of laser-cooled Cs atoms. The change in gravitational field along one dimension is measured when a well-characterized Pb mass is displaced. Here, we report a value of
G
= 6.693 × 10
–11
cubic meters per kilogram second squared, with a standard error of the mean of ±0.027 × 10
–11
and a systematic error of ±0.021 × 10
–11
cubic meters per kilogram second squared. The possibility that unknown systematic errors still exist in traditional measurements makes it important to measure
G
with independent methods.
Neutrino Astrophysics Experiments Beneath the Sea and Ice
Authors: Halzen Francis
Published: January 2007

Neutrino astronomy beyond the Sun was first imagined in the late 1950s. A neutrino detector at the bottom of Lake Baikal, the deployment of detectors in the Mediterranean Sea, and the construction of a kilometer-scale neutrino telescope at the South Pole exemplify current efforts to realize this dream.
Ethical difficulties in clinical practice: experiences of European doctors
Authors: Hurst S A , Perrier A , Pegoraro R , Reiter-Theil S , Forde R , Slowther A-M , Garrett-Mayer E , Danis M
Published: January 2007

Background:Ethics support services are growing in Europe to help doctors in dealing with ethical difficulties. Currently, insufficient attention has been focused on the experiences of doctors who have faced ethical difficulties in these countries to provide an evidence base for the development of these services.

Methods:A survey instrument was adapted to explore the types of ethical dilemma faced by European doctors, how they ranked the difficulty of these dilemmas, their satisfaction with the resolution of a recent ethically difficult case and the types of help they would consider useful. The questionnaire was translated and given to general internists in Norway, Switzerland, Italy and the UK.

Results:Survey respondents (n = 656, response rate 43%) ranged in age from 28 to 82 years, and averaged 25 years in practice. Only a minority (17.6%) reported having access to ethics consultation in individual cases. The ethical difficulties most often reported as being encountered were uncertain or impaired decision-making capacity (94.8%), disagreement among caregivers (81.2%) and limitation of treatment at the end of life (79.3%). The frequency of most ethical difficulties varied among countries, as did the type of issue considered most difficult. The types of help most often identified as potentially useful were professional reassurance about the decision being correct (47.5%), someone capable of providing specific advice (41.1%), help in weighing outcomes (36%) and clarification of the issues (35.9%). Few of the types of help expected to be useful varied among countries.

Conclusion:Cultural differences may indeed influence how doctors perceive ethical difficulties. The type of help needed, however, did not vary markedly. The general structure of ethics support services would not have to be radically altered to suit cultural variations among the surveyed countries.
How tall is too tall? On the ethics of oestrogen treatment for tall girls
Authors: Louhiala P
Published: January 2007

Oestrogen treatment for girls, to prevent psychosocial problems due to extreme tallness, has been available for almost 50 years but uncertainty about its position prevails. The ethical problems of this treatment are focused on in this paper. After a brief overview on historical and medical aspects, ethical issues such as the general justification of oestrogen treatment, evaluation of its success and ethical concerns related to research in this subject are dealt with in detail.
Molecular basis for calcium signaling in hepatic stellate cells
Authors: Kruglov Emma A. , Correa Paulo R. A. V. , Arora Gaurav , Yu Jin , Nathanson Michael H. , Dranoff Jonathan A.
Published: January 2007

Progressive liver fibrosis (with the resultant cirrhosis) is the primary cause of chronic liver failure. Hepatic stellate cells (HSCs) are critically important mediators of liver fibrosis. In the healthy liver, HSCs are quiescent lipid-storing cells limited to the perisinusoidal endothelium. However, in the injured liver, HSCs undergo myofibroblastic transdifferentiation (activation), which is a critical step in the development of organ fibrosis. HSCs express P2Y receptors linking extracellular ATP to inositol (1,4,5)-trisphosphate-mediated cytosolic Ca2+signals. Here, we report that HSCs express only the type I inositol (1,4,5)-trisphosphate receptor and that the receptor shifts into the nucleus and cell extensions upon activation. These cell extensions, furthermore, express sufficient machinery to enable local application of ATP to evoke highly localized Ca2+signals that induce localized contractions. These autonomous units of subcellular signaling and response reveal a new level of subcellular organization, which, in turn, establishes a novel paradigm for the local control of fibrogenesis in the liver.
Soluble guanylyl cyclase expression is reduced in LPS-induced lung injury
Authors: Glynos Constantinos , Kotanidou Anastasia , Orfanos Stylianos E. , Zhou Zongmin , Simoes Davina C. M. , Magkou Christina , Roussos Charis , Papapetropoulos Andreas
Published: January 2007

Soluble guanylyl cyclase (sGC) is a cGMP-generating enzyme implicated in the control of smooth muscle tone that also regulates platelet aggregation. Moreover, sGC activation has been shown to reduce leukocyte adherence to the endothelium. Herein, we investigated the expression of sGC in a murine model of LPS-induced lung injury and evaluated the effects of sGC inhibition in the context of acute lung injury (ALI). Lung tissue sGC α1 and β1 subunit protein levels were determined by Western blot and immunohistochemistry, and steady-state mRNA levels for the β1 subunit were assessed by real-time PCR. LPS inhalation resulted in a decrease in β1 mRNA levels, as well as a reduction in both sGC subunit protein levels. Decreased α1 and β1 expression was observed in bronchial smooth muscle and epithelial cells. TNF-α was required for the LPS-triggered reduction in sGC protein levels, as no change in α1 and β1 levels was observed in TNF-α knockout mice. To determine the effects of sGC blockade in LPS-induced lung injury, mice were exposed to 1H-[1,2,4]oxodiazolo[4,3-a]quinoxalin-l-one (ODQ) prior to the LPS challenge. Such pretreatment led to a further increase in total cell number (mainly due to an increase in neutrophils) and protein concentration in the bronchoalveoalar lavage fluid; the effects of ODQ were reversed by a cell-permeable cGMP analog. We conclude that sGC expression is reduced in LPS-induced lung injury, while inhibition of the enzyme with ODQ worsens lung inflammation, suggesting that sGC exerts a protective role in ALI.
Effect of Rapamycin on Hepatocyte Function and Proliferation Induced by Growth Factors
Authors: Tomiya Tomoaki , Yamaoka Miho , Inoue Yukiko , Nishikawa Takako , Yanase Mikio , Ikeda Hitoshi , Tejima Kazuaki , Nagashima Kayo , Watanabe Naoko , Omata Masao , Fujiwara Kenji
Published: January 2007

Background: Rapamycin is a specific inhibitor of the mammalian target of rapamycin (mTOR). The effect of rapamycin on proliferation and cellular function was studied in hepatocytes stimulated by hepatocyte growth factor (HGF) or transforming growth factor-α (TGFα). Methods and Results: When isolated rat hepatocytes were cultured at low density, the addition of HGF or TGFα increased DNA synthesis but did not affect albumin or fibrinogen concentrations in the medium. In contrast, in hepatocytes cultured at high density, the albumin and fibrinogen concentrations, but not DNA synthesis, were increased by HGF or TGFα. The HGF- or TGFα-induced increase in DNA synthesis and in albumin or fibrinogen concentrations was suppressed by the addition of rapamycin, as well as wortmannin, a phosphatidylinositol-3 kinase inhibitor. Conclusion: HGF and TGFα stimulate proliferation and function of hepatocytes depending upon the conditions, and rapamycin inhibited these stimulatory effects, possibly by inhibiting the mTOR-dependent signaling pathway.
Effects of Growth Hormone on Growth, Insulin Resistance and Related Hormones (Ghrelin, Leptin and Adiponectin) in Turner Syndrome
Authors: Darendeliler Feyza , Aycan Zehra , Cetinkaya Ergun , Vidilisan Sadi , Bas Firdevs , Bideci Aysun , Demirel Fatma , Darcan Sukran , Buyukgebiz Atilla , Yildiz Metin , Berberoglu Merih , Arslanoglu Ilknur , Bundak Ruveyde
Published: January 2007

Background:Concomitant evaluation of the metabolic and growth-promoting effects of growth hormone (GH) therapy in Turner syndrome (TS) may be used in the prediction of the growth response to GH therapy. Aim: To evaluate the metabolic effects of GH therapy in TS and correlation with the short-term growth response. Patients: 24 prepubertal children with TS, aged 9.4 ± 2.6 years were followed for auxology and IGF-I, IGFBP-3, leptin, ghrelin, adiponectin, lipids and OGTT results in a prospective multicenter study. Intervention: GH (Genotropin®) in a dose of 50 µg/kg/day for 1 year. Results: Height standard deviation score (SDS) increased from –3.9 ± 1.5 to –3.5 ± 1.4 (p = 0.000) on therapy. BMI did not change. IGF-I SDS increased from –2.3 ± 0.4 to –1.6 ± 1.1 at 3 and 6 months (p = 0.001) and decreased thereafter. Serum leptin decreased significantly from 2.3 ± 3.9 to 1.7 ± 5.3 ng/ml (p = 0.022) at 3 months and increased afterwards. Serum ghrelin decreased from 1.2 ± 0.8 to 0.9 ± 0.4 ng/ml (p = 0.005) with no change in adiponectin. Basal and stimulated insulin levels also increased significantly. Δ height SDS over 1 year showed a significant correlation with Δ IGF-I0–3 months (r = 0.450, p = 0.027). Conclusion: IGF-I may be considered as a marker of growth response in TS at short term. Leptin shows a decrease at short term but does not have a correlation with growth response. The decrease in ghrelin in face of unchanged weight seems to be associated with increase in IGF-I and insulin levels. The unchanged adiponectin levels in spite of an increase in insulin levels indicates that adiponectin is mainly affected by weight, not insulin.
Platelets as Immune Cells
Authors: von Hundelshausen Philipp , Weber Christian
Published: January 2007

Beyond an eminent role in hemostasis and thrombosis, platelets are characterized by expert functions in assisting and modulating inflammatory reactions and immune responses. This is achieved by the regulated expression of adhesive and immune receptors on the platelet surface and by the release of a multitude of secretory products including inflammatory mediators and cytokines, which can mediate the interaction with leukocytes and enhance their recruitment. In addition, platelets are characterized by an enormous surface area and open canalicular system, which in concert with specialized recognition receptors may contribute to the engulfment of serum components, antigens, and pathogens. Platelet-dependent increases in leukocyte adhesion may not only account for an exacerbation of atherosclerosis, for arterial repair processes, but also for lymphocyte trafficking during adaptive immunity and host defense. This review compiles a selection of platelet-derived tools for bridging inflammation and vascular disease and highlights the molecular key components governing platelet-mediated mechanisms operative in immune surveillance, vascular remodeling, and atherosclerosis.
Asymmetric Dimethylarginine in Cerebral Small Vessel Disease
Authors: Khan Usman , Hassan Ahamad , Vallance Patrick , Markus Hugh S.
Published: January 2007

Background and Purpose—

Endothelial dysfunction may play a causal role in cerebral small vessel disease (SVD). Asymmetric dimethylarginine (ADMA), a circulating endogenous inhibitor of nitric oxide, has been implicated in endothelial dysfunction, particularly in hyperhomocystinemia, a known risk factor for SVD. We determined if ADMA was elevated in SVD, correlated with disease severity, and interacted with homocysteine.

Methods—

ADMA and homocysteine levels were determined in 47 consecutive symptomatic SVD patients and 38 controls. SVD was graded by leukoariosis severity and number of lacunar infarcts.

Results—

Mean (and SD) ADMA was higher in SVD patients compared with controls (0.814 [0.145] versus 0.747 [0.184] μmol/L;
P
=0.014) after controlling for age, gender, vascular risk factors, and creatinine clearance. Additionally controlling for homocysteine had only a small effect on this relationship (
P
=0.055). Mean homocysteine was higher in SVD cases compared with controls (15.14 [5.59] versus 12.49 [4.15] μmol/L;
P
=0.035). Leukoariosis grade correlated positively with ADMA (
P
=0.026) and homocysteine (
P
=0.003). Lacunar grade correlated with homocysteine (
P
=0.017), but not ADMA.

Conclusions—

ADMA is independently associated with SVD and correlates with leukoariosis severity.
The Textual History of the Materia Medica in the Han Period: A System-Theoretical Reconsideration
Authors:   Schmidt
Published: January 2007

The purpose of the present essay is to throw light on the process of generating the materia medica in China. Western forms of medical pluralism led to the appearance of the first known materia medica in approximately the 4th century BC. In the East, by contrast, the emergence of a materia medicacan merely be localized to a period certainly no later than the 2nd century AD. Thus, existing theories suggest a gap of more than five centuries between the evolution of the materia medica in each of the two hemispheres. This gap, the author suspects, is much too large. The study shows that one can track four lineages of material medica in the transmitted literature of the Han period. However, each lineage appears to be an upgraded form of materia medica. Thus, the emergence of a materia medica must have antedated these four lineages. The author concludes that it is precisely this multiple reproduction of a materia medica that reflects the human interest in establishing and consolidating an infrastructure for health care. L'objet de cet essai est d'éclairer le processus d'élaboration des materia medica en Chine. Les formes occidentales de pluralisme médi cal ont conduit à l'apparition des premières materia medica connues approximativement au ive siècle avant notre ère. En Extrême-Orient, en revanche, l'émergence d'une materia medica ne peut être située que dans une période qui ne doit pas être postérieure au iie siècle de notre ère. En d'autres termes, les théories existantes suggèrent un décalage de plus de cinq siècles entre l'évolution des materia medica dans l'un et l'autre hémisphère. Ce décalage, pense l'auteur, est beaucoup trop grand. La présente étude montre que l'on peut retracer quatre lignées de materia medica dans les textes des Han qui nous ont été transmis. Or, chacune de ces lignées se présente comme une forme révisée de materia medica. L'émergence d'une materia medica doit donc être antérieure à ces quatre lignées. L'auteur conclut que cette reproduction multiple de materia medica reflète en fait l'intérêt humain pour établir et consolider une infrastructure sanitaire.
What Did Su Che See in the North? Publishing Regulations, State Security, and Political Culture in Song China
Authors: De Weerdt Hilde
Published: January 2007

This article investigates two kinds of publishing regulations issued during the Song Dynasty, those governing cross-border smuggling of written texts and those on texts relating to border affairs. It argues that the Song court's and Song officials' anxiety about the smuggling of state documents into the surrounding empires was foremost an expression of their concern over the circulation of state documents among literate elites inside Song territory. The analysis of cross-border smuggling focuses on alleged smuggling "to the north," i.e., to the empires bordering on the Song Empire's northern frontier. In order to substantiate the systematic connections made among Song publishing regulations, official and elite constructions of "the north" and elite political culture, the author contrasts prohibitions on the cross-border smuggling of texts to those governing other goods and compares publishing regulations in The Tang Code and The Classified Laws of the Qingyuan Period of ca. 1202. Cette étude s'intéresse à deux sortes de règlements sur les publications promulgués par les Song: ceux qui régissaient la contrebande transfrontalière des textes écrits et ceux qui concernaient les textes relatifs aux affaires frontalières. L'argument développé est que l'inquiétude de la cour et des fonctionnaires des Song relativement à la contrebande des documents d'État au profit des empires voisins reflétait avant tout leurs craintes concernant la circulation des documents gouvernementaux au sein des élites lettrées sur le territoire même des Song. L'analyse de la contrebande transfrontalière se concentre sur la prétendue contrebande vers "le Nord", autrement dit les empires jouxtant les Song sur leur frontière nord. L'auteur justifie les rapports qu'elle établit systématiquement entre les règlements Song sur les publications, la construction de la notion de "Nord" au sein de la bureaucratie et de l'élite lettrée, et la culture politique de l'élite, en comparant les prohibitions relatives à la contrebande transfrontalière des textes et celles concernant d'autres produits, et compare les règlements sur les publication dans le Code des Tang et dans la Législation classifiée de l'ère Qingyuan (vers 1202).
Assessing Leadership Among Chinese Secondary Students in Hong Kong: The Use of the Roets Rating Scale for Leadership
Authors: Chan David W.
Published: January 2007

The leadership characteristics of 163 Chinese secondary students in Hong Kong were assessed with the use of the Roets Rating Scale for Leadership (RRSL). Higher self-ratings were found for characteristics related to aspiring to leadership and achievement, openness to novel experiences and different perspectives, and high energy level than for other characteristics. Three dimensions identifiable as task orientation, leadership self-efficacy, and leadership flexibility emerged, testifying to the complexity of leadership skills and characteristics. The study also provided evidence that the RRSL was a viable self-report measure of leadership among Chinese adolescents with acceptable reliability and convergent validity with other measures of leadership based on observed behavioral characteristics. Repeated assessment also indicated that the RRSL could be used to monitor the effects of leadership training programs.
Finding “g”: Easy Viewing Through Higher Order Factor Analysis
Authors: Pyryt Michael C.
Published: January 2007

The purpose of this paper is to illustrate the usefulness of higher order factor analysis in demonstrating the presence of general intelligence as the factor underlying performance on 13 indicators of four of Gardner's (1983) multiple intelligence. Data from Plucker, Callahan, and Tomchin (1996) was reanalyzed using maximum likelihood extraction with oblique rotation. The oblique correlation matrix was factor analyzed. Consistent with Carroll's (1993) factor analytic survey of human cognitive abilities, results indicated that a general intelligence factor underlies correlations between first-order factors.
Measuring the Outcomes of State Policies for Gifted Education: An Equity Analysis of Texas School Districts
Authors: Baker Bruce D.
Published: January 2007

Policy research in gifted education continues to maintain a relatively narrow focus, dealing primarily with policy inputs like the presence and design of written mandates or the existence or lack of state finding. Yet, little attention has been paid to the actual distribution of programming opportunities for gifted children. There continues to be a vast disconnect between policy analysts and gifted educators. The objective of this article is to help bridge that gap by (1) introducing a set of policy tools for measuring the outcomes of gifted education policies and (2) applying those tools to data on the distribution of gifted education spending and designated personnel in the state of Texas. According to generally accepted policy benchmarks, the analyses performed indicate (a) continued vast inequities across school districts in the availability of resources and (b) unacceptable correlations between student population characteristics, community wealth, and the availability of opportunity.
A Talent Profile for Facilitating Talent Development in Schools
Authors: Kay Sandra I.
Published: January 2007

The Talent Profile is a cumulative record that describes and visually synthesizes a student's outstanding achievements from K-12 in any valued field of human activity in which children and adolescents are active, whether at school, at home, or in the community. This system provides a method of communication and translation between disciplines (e.g., academics, arts, athletics) that serves multiple educational purposes as it honors individual development in areas of expertise. Individual differences are highlighted that begin to map aptitudes and achievements in multiple domains and offer a range of five levels of expectations/benchmarks for the high-end learner. Record keeping of the development of expertise in talent domains will also inform future research currently devoid of longitudinal, biographical data.
An Evaluation of the Catalyst Program: Consultation and Collaboration in Gifted Education
Authors: Landrum Mary S.
Published: January 2007

A recent evaluation of the Catalyst Program, a resource consultation and collaboration program in gifted education, was conducted in order to investigate the effects of student academic performance and teacher competencies, as well as the effectiveness of the consulting process applied to gifted education. In a two-year pilot program, general educators and gifted education specialists at 10 elementary schools in a large, urban school district consulted and collaborated with one another to provide differentiated educational experiences to gifted learners. Results indicate that the model was an effective service delivery strategy for providing differentiated education to gifted learners, had positive spill-over effects for the entire school, led to a redefined role of the gifted education specialist, and initiated an articulation of the nature of the consulting process when applied to gifted education.
A Curriculum Study of Gifted-Student Learning in the Language Arts
Authors: VanTassel-Baska Joyce , Zuo Li , Avery Linda D. , Little Catherine A.
Published: January 2007

This curriculum study of gifted-student learning in the language arts explores questions of curriculum efficacy related to the nature of the learner, the type of grouping model employed, and the strength of a curriculum treatment emphasizing literary analysis and interpretation and persuasive writing. The study further explores the use of curriculum effectiveness data to improve instruction the next time a unit of study is taught. Findings suggest that the curriculum treatment produces both significant and important learning outcomes for gifted students across 18 school district entities. Implications for further research and practice are highlighted.
Constructions of High Academic Achievement Through the Analysis of Critical Events
Authors: Koro-Ljungberg Mirka
Published: January 2007

In this study, critical events in the career development of Finnish Academy professors describe the trajectories of their achievement and success throughout the lifespan. Focused open-ended interviews, curricula vitae, and field notes produced representations of high achievement, which in this article relate to the system, model of talent, to the concept of successful intelligence, and, more widely, to the poststructural understanding of knowledge construction. The purpose of the article is to describe the primary themes resulting from descriptive analysis. These themes included mentors, academic years abroad, strong interest in the domain, and luck. Also described are the transformative themes, which comprised situated construction of academic career and reflectiveness that lay beyond the constitution of descriptive themes. Interpretation moves from descriptive to transformative analysis and is supported with the stories of “Gatekeeper,” “Professional Leader,” and “Disappointed Idealist”. These scientists' stories illustrate the situatedness and individualistic nature of scientific achievement, connecting and reconnecting issues of time, place, and power in various ways.
The Theory of Successful Intelligence as a Basis for Gifted Education
Authors: Sternberg Robert J. , Grigorenko Elena L.
Published: January 2007

A number of models are available for use in gifted education. The theory of successful intelligence, one such model, provides a basis for identification, intervention, and evaluation in gifted programs. This article describes the model, allowing practitioners and other interested parties to apply the model in a gifted education environment.

The article contains four main parts. The first part presents the theory of successful intelligence and data in support of it. The second part shows how to implement the model in schools and presents data in support of the success of its school implementation. The third part relates the theory of successful intelligence to other models of gifted education. The fourth part briefly draws some conclusions.
Bridging the Gap: A Tool and Technique to Analyze and Evaluate Gifted Education Curricular Units
Authors: Purcell Jeanne H. , Burns Deborah E. , Tomlinson Carol Ann , Imbeau Marcia B. , Martin Judith L.
Published: January 2007

Research on the quality of educational standards, our knowledge about the quality of textbooks, and the performance of high-achieving students on international assessments all point to the need for exemplary curricula for gifted and talented young people. The gap between research in these areas and the needs of gifted and talented learners is startlingly clear. This article includes information about the development of a rubric that was originally designed to assess the quality of curricular units that are submitted annually to the National Association for Gifted Children (NAGC) Curriculum Division's Curriculum Competition. The article also includes information about 4 different, but related, uses for the rubric. Ultimately, we hope that the use of this tool and assessment technique by practitioners across the country will begin to close the enormous gap between the learning needs of gifted and talented young people and curricula.
Factors That Differentiate Underachieving Gifted Students From High-Achieving Gifted Students
Authors: McCoach D. Betsy , Siegle Del
Published: January 2007

The purpose of this study was to examine whether gifted achievers and gifted underachievers differ in their general academic self-perceptions, attitudes toward school, attitudes toward teachers, motivation and self-regulation, and goal valuation. The sample consisted of 56 gifted underachievers and 122 gifted achievers from 28 high schools nationwide. Gifted achievers and gifted underachievers differed in their attitudes toward school, attitudes toward teachers, motivation/self-regulation, and goal valuation, but not their academic self-perceptions. In addition, the logistic regression analysis correctly classified over 81% of the sample as either gifted achievers or gifted underachievers using their motivation/self-regulation and goal valuation self-ratings. This study represents an important step toward quantifying factors related to the underachieviement of gifted adolescents.
To No Longer Educate the Gifted: Programming for Gifted Students Beyond the Era of Inclusionism
Authors: Bernal Ernesto M.
Published: January 2007

For many educators, the goal of programs for the gifted is “the education of identified gifted students.” This article argues that this goal makes gifted and talented (GT) programs vulnerable to discontinuation and relegates gifted children to inclusionary, regular classrooms where their needs are rarely met. To avoid these possibilities, the goal of GT should be reformulated to “the development of gifted young adults.” This goal has several advantages, including the possibility of a more enriched curriculum and a more diverse group of children with higher creative-productive potential. It also includes the overt recognition. that these children require both differentiated instruction and specialized guidance to acquire a measure of expertise, establish a strong sense of self, and make personally satisfying career choices. The Growing Giftedness model presented would have GT students work more closely with adults and with one another than the inclusionary model or part-time gifted programs can allow. In addition, this model adumnbrates the elements of a fill-time program.
Partnerships in Science Learning: Museum Outreach and Elementary Gifted Education
Authors: Melber Leah M.
Published: January 2007

The purpose of this study was to investigate the impact of a specially designed museum science program on academically gifted elementary students. The program focused on inquiry-based activities that paralleled the work of museum scientists. A pre- and postattitude questionnaire and a parental postquestionnaire were used to investigate changes in (a) attitude toward science careers, (b) understanding of scientific work and scientists, and (c) content knowledge gains of participants. A version of the Draw-a-Scientist Test (DAST) was incorporated to gauge student perceptions of scientific work. After participation, students indicated a greater understanding of science careers and an increased desire to explore careers in science. Student questionnaire and illustration analysis identified an increase in participants’ content knowledge and understanding of scientific work. Parental questionnaires supported these findings.