bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vorticity Structures in the Tropical Pacific from a Numerical Simulation
Authors: Ubelmann Clement , Fu Lee-Lueng 
Published: March 2011

Abstract
The small-scale variability of the tropical Pacific is studied with the simulations from a numerical model in terms of vorticity structures. A Lagrangian method based on the Okubo–Weiss parameter is used to identify the structures and track their main characteristics. Between 8°S and 8°N, the structure characteristics are spatially inhomogeneous compared to higher latitudes. They can be grouped into three categories: anticyclonic and cyclonic structures off the equator and the equatorial structures between 2°S and 2°N. They all have a strong annual cycle with maximum presence from September to March, except during strong El Niño years, when the number of structures becomes very low. Off the equator from 2° to 8°, the anticyclonic structures dominate, but with drastically different characteristics north and south of the equator. In the north, large nonlinear vortices develop (known as the tropical instability vortices) in phase with the 30–35-day oscillation related to an unstable first-meridional-mode Rossby waves. In the south, mostly fragmentary linear structures are present, with lower propagation speeds. The equatorial structures are mostly counterclockwise. The larger ones tend to be linear and are clearly associated with Yanai waves. The large majority of the cyclonic structures off the equator are also quite linear and smaller and less numerous than the anticyclonic structures. However, some of them are nonlinear with vorticity values higher than 2 times the Coriolis parameter.
Social determinants of cardiac disease biomarkers: investigating a Swedish male cohort at ages 50 and 70
Authors: Khanolkar Amal , Vågerö Denny , Koupil Ilona 
Published: March 2011

Background: Social status is associated with cardiovascular disease (CVD) prevalence and incidence.Aims: to investigate relationships between socioeconomic position (SEP) and common CVD biomarkers including adiponectin not previously investigated in a Swedish-population sample, and to assess if these associations changed with age.Design: Population-based longitudinal cohort study of men born 1920–24 with clinical measurements, blood samples, questionnaire data, and register-based information on SEP and cause of death.Methods: A total of 2322 men attended an investigation at age 50 of which 1221 attended a reinvestigation at age 70. Association between SEP and CVD biomarkers [cholesterol, low-density lipoprotein/high-density lipoprotein (LDL/HDL), apolipoprotein (Apo) ApoB/ApoA1, and adiponectin] were analysed by linear regression (adjusted for age, body mass index, and physical activity). SEP was measured as occupational class and educational level. CVD mortality over 36 years of follow-up was analysed by Cox regression.Results: At age 50, we found a significant inverse association of education with cholesterol level, LDL/HDL ratio and ApoB/ApoA1 ratio. Cholesterol was also associated with occupational class, statistically significant after adjustment for all covariates. At age 70, no significant associations were found between either measurement of SEP and any of the biomarkers studied. Highest educated men had decreased risk for CVD mortality during follow-up.Conclusions: Associations of SEP with cholesterol levels and LDL/HDL ratio that exist at age 50 are no longer apparent in the same group of men at age 70. We found no significant association between SEP and adiponectin levels at age 70.
Myeloid-derived suppressor cells express the death receptor Fas and apoptose in response to T cell–expressed FasL
Authors: Sinha Pratima , Chornoguz Olesya , Clements Virginia K. , Artemenko Konstantin A. , Zubarev Roman A. , Ostrand-Rosenberg Suzanne 
Published: March 2011

AbstractMyeloid-derived suppressor cells (MDSCs) inhibit adaptive and innate immunity and accumulate in the blood of persons with cancer, chronic inflammation, trauma, infection, and stress. Some of the factors inducing their accumulation are known; however, mechanisms regulating their turnover have not been identified. Mass spectrometry showed prominent expression of apoptosis pathway proteins, suggesting that MDSC turnover may be regulated by Fas-FasL–mediated apoptosis. This hypothesis was confirmed by showing that blood MDSCs induced by 3 mouse tumors were Fas+ and apoptosed in response to Fas agonist in vitro and to activated FasL+ T cells in vivo. FasL-deficient mice contained significantly more blood MDSCs than FasL+/+ mice, and after removal of primary tumors MDSCs regressed in STAT6−/− and CD1−/− mice but not in STAT6−/−FasL−/− or CD1−/−FasL−/− mice. Fas+ macrophages and dendritic cells did not apoptose in response to activated T cells, indicating that Fas-FasL regulation of myeloid cells was restricted to MDSCs. These results identify a new mechanism regulating MDSC levels in vivo and show a retaliatory relationship between T cells and MDSCs in that MDSCs suppress T-cell activation; however, once activated, T cells mediate MDSC apoptosis.
Kit-Shp2-Kit signaling acts to maintain a functional hematopoietic stem and progenitor cell pool
Authors: Zhu Helen He , Ji Kaihong , Alderson Nazilla , He Zhao , Li Shuangwei , Liu Wen , Zhang Dong-Er , Li Linheng , Feng Gen-Sheng 
Published: March 2011

AbstractThe stem cell factor (SCF)/Kit system has served as a classic model in deciphering molecular signaling events in the hematopoietic compartment, and Kit expression is a most critical marker for hematopoietic stem cells (HSCs) and progenitors. However, it remains to be elucidated how Kit expression is regulated in HSCs. Herein we report that a cytoplasmic tyrosine phosphatase Shp2, acting downstream of Kit and other RTKs, promotes Kit gene expression, constituting a Kit-Shp2-Kit signaling axis. Inducible ablation of PTPN11/Shp2 resulted in severe cytopenia in BM, spleen, and peripheral blood in mice. Shp2 removal suppressed the functional pool of HSCs/progenitors, and Shp2-deficient HSCs failed to reconstitute lethally irradiated recipients because of defects in homing, self-renewal, and survival. We show that Shp2 regulates coordinately multiple signals involving up-regulation of Kit expression via Gata2. Therefore, this study reveals a critical role of Shp2 in maintenance of a functional HSC/progenitor pool in adult mammals, at least in part through a kinase-phosphatase-kinase cascade.
Stress in psychiatrists: coping with a decade of rapid change
Authors: Rathod Shanaya , Mistry Minal , Ibbotson Ben , Kingdon David 
Published: March 2011

Aims and methodThe study explored the impact of National Health Service changes on the working and personal lives of psychiatrists. A questionnaire survey was carried out with psychiatrists working in the South Eastern Division of the Royal College of Psychiatrists.ResultsThe response rate was 44.9%. Changes to services have reduced stress in some areas, but increased stress in others. Over the past decade early retirement has become less popular, but psychiatrists have been more likely to self-prescribe and have suicidal thoughts.Clinical implicationsThe increasing involvement of psychiatrists in leadership may be a way to reduce adverse impacts of future changes on their working lives.
Mental states and political decisions
Authors: Freedman Lawrence 
Published: March 2011

SummaryThe Owen/Russell thesis on the impact of mental illness on political leaders is considered. The importance of the issue is acknowledged. Using the examples of President Kennedy and the Shah of Iran it is argued that what constitutes good decision-making is contingent on circumstances and evaluated by outcomes. There are often alternative explanations to mental impairment for poor decision-making, and that hubris is not the only possible failing. Last, democratic systems have better mechanisms than authoritarian regimes to address the problems posed by leaders who are physically or mentally ill.
Psychiatry and politicians – afterword
Authors: Owen Lord David 
Published: March 2011

SummaryContempt is one of the more important signs of hubris syndrome. Lying to Parliament or the courts is often a sign of someone in thrall to hubris. In business and banking, collective or corporate hubris is not uncommon as is hubris syndrome among its most powerful leaders. BP, RBS and HBOS need to be the subject of serious case studies for hubris, ‘group think’, tunnel vision, closed minds or silo thinking. There are indications of a neurobiological explanation for the intoxication of power in hubris syndrome.
Highly Efficient Pd/SiO2–Dimethyl Sulfoxide Catalyst System for Selective Semihydrogenation of Alkynes
Authors: Takahashi Yusuke , Hashimoto Norifumi , Hara Takayoshi , Shimazu Shogo , Mitsudome Takato , Mizugaki Tomoo , Jitsukawa Koichiro , Kaneda Kiyotomi 
Published: March 2011

Abstract
Silica-supported Pd nanoparticles (Pd/SiO2) with dimethyl sulfoxide (DMSO) show excellent catalytic activity and selectivity for the semihydrogenation of alkynes. Small amounts of DMSO drastically suppress the overhydrogenation and isomerization of alkenes. This catalyst system is also applicable to both internal and terminal alkynes. Furthermore, the Pd/SiO2 catalyst was separable from the reaction mixture after the hydrogenation and reusable without loss of its high catalytic activity or selectivity.
Effectiveness of therapeutic lymphography on lymphatic leakage
Authors: Alejandre-Lafont Enrique , Krompiec Christoph , Rau Wigbert S , Krombach Gabriele A 
Published: March 2011

Background The number of conventional lymphographies has declined markedly since the introduction of cross-sectional imaging techniques. Nevertheless, lymphography has a high potential as a reliable method to visualize and directly occlude lymphatic leaks. When used as a distinct radiological procedure with the intention to treat, this application can be described as therapeutic lymphography. Purpose To investigate if therapeutic lymphography is a reliable method to treat lymphatic leakage when conservative treatment fails and to investigate which parameters influence the success rate. Material and Methods Between August 1995 and January 2008, 50 patients with lymphatic leakage in form of chylothorax, chylous ascites, lymphocele, and lymphatic fistulas underwent conventional therapeutic lymphography after failure of conservative therapy. Of these 50 patients, seven could not be statistically evaluated in our retrospective study: one patient died of cancer 1 day after lymphography, and six were excluded due to various technical problems. The remaining 43 patients were evaluated. Therapeutic success was evaluated and correlated to the volume of lymphatic leakage (more or less than 500 mL/day), as assessed by drainage. Results In nearly 79% of patients, the location of the leak could be detected, and surgical intervention could be planned when therapeutic lymphography failed. Due to the irrigating effect of the contrast medium (lipiodol), the lymphatic leak could be completely occluded in 70% of patients when the lymphatic drainage volume was less than 500 mL/day. Even when lymphatic drainage was higher than 500mL/day, therapeutic lymphography was still successful in 35% of the patients. The overall success rate in patients with failed conservative treatment was 51%. Success did not depend on other factors such as age and sex, cause of lymph duct damage, or time elapsed between lymphatic injury and intervention. Conclusion Therapeutic lymphography is an effective method in the treatment of lymphatic leakage when conservative therapy fails. The volume of lymphatic drainage per day is a significant predictor of the therapeutical success rate.
Correlation of radiation dose and heart rate in dual-source computed tomography coronary angiography
Authors: Laspas Fotios , Tsantioti Dimitra , Roussakis Arkadios , Kritikos Nikolaos , Efthimiadou Roxani , Kehagias Dimitrios , Andreou John 
Published: March 2011

Background Computed tomography coronary angiography (CTCA) has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but the relatively high radiation dose remains a major concern. Purpose To evaluate the relationship between radiation exposure and heart rate (HR), in dual-source CTCA. Material and Methods Data from 218 CTCA examinations, performed with a dual-source 64-slices scanner, were statistically evaluated. Effective radiation dose, expressed in mSv, was calculated as the product of the dose-length product (DLP) times a conversion coefficient for the chest (mSv = DLPx0.017). Heart rate range and mean heart rate, expressed in beats per minute (bpm) of each individual during CTCA, were also provided by the system. Statistical analysis of effective dose and heart rate data was performed by using Pearson correlation coefficient and two-sample t-test. Results Mean HR and effective dose were found to have a borderline positive relationship. Individuals with a mean HR >65 bpm observed to receive a statistically significant higher effective dose as compared to those with a mean HR ≤65 bpm. Moreover, a strong correlation between effective dose and variability of HR of more than 20 bpm was observed. Conclusion Dual-source CT scanners are considered to have the capability to provide diagnostic examinations even with high HR and arrhythmias. However, it is desirable to keep the mean heart rate below 65 bpm and heart rate fluctuation less than 20 bpm in order to reduce the radiation exposure.
The value of intravascular phased-array imaging in endovascular treatment of thoracic aortic pathology
Authors: Eriksson Mats-Ola , Nyman R 
Published: March 2011

BackgroundCareful pre-, intra- and postoperative diagnostics in endovascular treatment of thoracic aortic pathology is crucial for a favourable outcome. Computer tomography (CT) and digitally subtracted angiography (DSA) do not always provide sufficient diagnostic information.PurposeTo report our primary experiences of using intraluminal phased-array imaging (IPAI) as an additive tool for diagnostics and endovascular treatment of thoracic aortic pathology.Material and MethodsEleven patients, nine men and two women (mean age 60, range 45) were examined intraoperatively with IPAI in stentgraft procedures of thoracic aortic pathology.ResultsIPAI could detect and visualize the entries and re-entries in the intima. Aortic branch vessels could be visualized for patency both during and immediately after stentgraft deployment. It was also possible to detect ceased blood flow in the false lumen or aneurysmal sac after stentgraft deployment.ConclusionIPAI is a helpful tool for diagnostics and for guiding stentgraft placing in the treatment of thoracic aortic pathology.
Two-dimensional versus three-dimensional CT angiography in analysis of anatomical suitability for stentgraft repair of abdominal aortic aneurysms
Authors: Pitoulias Georgios A , Donas Konstantinos P , Schulte Stefan , Aslanidou Eleni A , Papadimitriou Dimitrios K 
Published: March 2011

Background The morphological analysis prior to endovascular abdominal aneurysm repair (EVAR) plays an important role in long-term outcomes. Post-imaging analysis of computed tomographic angiography (CTA) by three-dimensional reconstruction with central lumen line detection (CLL 3D-CTA) enables measurements to be made in orthogonal slices. This might be more precise than equal post-imaging analysis in axial slices by two-dimensional computed tomographic angiography (2D-CTA). Purpose To evaluate the intra- and interobserver variability of CLL 3D-CTA and 2D-CTA post-imaging analysis methods and the agreement between them in pre-EVAR suitability analysis of patients with abdominal aortic aneurysm (AAA). Material and Methods Anonymized CTA data-sets from 70 patients with AAA were analyzed retrospectively. Length measurements included proximal and distal aortic neck lengths and total distance from the lower renal artery to the higher iliac bifurcation. Width measurements included proximal and distal neck diameters, maximum AAA diameter and common iliac diameters just above the iliac bifurcations. The measurements were performed in random order by two vascular surgeons, twice per method with 1-month interval between readings. In the CLL 3D-CTA method we used semi-automated CLL detection by software and manual measurements on CTA slices perpendicular to CLL. The equal measurements in 2D-CTA were performed manually on axial CTA slices using a DICOM viewer workstation. The intra- and interobserver variability, as well as the agreement between the two methods were assessed by Bland-Altman test and bivariate correlation analysis. Results The intraobserver variability was significantly higher in 2D-CTA measurements for both readers. The interobserver variability was significant in 2D-CTA measurements of proximal neck dimensions while the agreement in CLL 3D-CTA analysis between the two readers was excellent in all studied parameters. The agreement between the two suitability analysis techniques was poor for both readers, especially in measurements of proximal neck's dimensions and in total aortoiliac length (p = 0.001). Conclusion In pre-EVAR morphological evaluation of AAAs the CLL-3D CTA post-imaging analysis has better intra- and interobserver correlation than 2D-CTA and might represent a useful tool for the proper selection of endograft's type and size.
High b-value diffusion-weighted MRI in differentiation between benign and malignant polypoid gallbladder lesions
Authors: Irie Hiroyuki , Kamochi Noriyuki , Nojiri Junichi , Egashira Yoshiaki , Sasaguri Kohei , Kudo Sho 
Published: March 2011

Background Several studies have reported the effectiveness of high b-value diffusion-weighted MR imaging (DWI) in the abdominal region, and have found that various malignant tumors may show high signal intensity on DWI, reflecting their high cellularity and/or their long relaxation time. The value of ADC measurement has also been documented for the diagnosis of several abdominal malignancies. Purpose To retrospectively evaluate the usefulness of high b-value DWI in differentiating between benign and malignant polypoid gallbladder lesions. Material and Methods The study population consisted of 10 benign (three hyperplastic polyps and seven adenomas) and 13 malignant (all adenocarcinomas) polypoid gallbladder lesions. DWI was evaluated by two observers. Qualitatively, the signal intensity of the lesions on DWI was visually evaluated and categorized as iso, high, or very high. Quantitatively, the ADC values of the lesions were measured from ADC maps. Statistical analysis was performed using a two-tailed Fisher's exact test and the Mann-Whitney test, respectively. Results Qualitative analysis revealed a statistical difference (P = 0.0041). Six of 10 benign lesions were categorized as iso, and the remaining four were categorized as high. In the 13 malignant lesions, one was categorized as iso, five as high, and seven as very high. The ADC values of the malignant lesions (1.34 ± 0.50 × 10–3 mm2/sec) were significantly lower than those of the benign lesions (2.26 ± 0.44 × 10–3 mm2/sec) (P = 0.00016). Conclusion High b-value DWI may be useful for differentiating between benign and malignant polypoid gallbladder lesions by the visual assessment of DWI and ADC measurement.
A feasibility study of MR elastography in the diagnosis of prostate cancer at 3.0T
Authors: Li Saying , Chen Min , Wang Wenchao , Zhao Weifeng , Wang Jianye , Zhao Xuna , Zhou Cheng 
Published: March 2011

Background MR elastography is a new imaging tool capable of non-invasively assessing the viscoelastic properties of tissues. The clinical application of MR elastography in the diagnosis of prostate cancer remains to be elucidated. Purpose To investigate the feasibility of MR elastography in the diagnosis of prostate cancer at 3.0T, and to assess the elasticity and viscosity of prostate cancer and benign prostatic disease. Material and Methods Eight patients (63 ± 7.25 years old) with 12 foci of prostate cancer and 10 patients (59 ± 3.25 years old) with 14 foci of prostatitis in the peripheral zone were evaluated by MRE. Ten healthy volunteers (41 ± 4.32 years old) with 18 ROIs in the peripheral zone of the prostate were also assessed with MR elastography as a control group. The results were confirmed by histopathological findings. All examinations were performed on a 3.0T Philips Achieva scanner. MRE was implemented by transmitting low-frequency longitudinal mechanical waves of 100Hz into the prostate with a transducer placed above the pubic bones. The phase images were reconstructed to acquire viscoelastic mapping. T-test was used to compare the mean elasticity and viscosity of prostate cancer and prostatitis. A comparison of prostate cancer and healthy prostate tissue in elasticity was also evaluated. The correlation of elasticity and Gleason scores between prostate cancer and prostatitis were retrospectively analyzed with Pearson Correlation. Results The mean elasticity and viscosity were significantly higher in the lesions with prostate cancer (6.55 ± 0.47 kPa, 6.56 ± 0.99 Pa.s, respectively) than in regions with prostatitis (1.99 ± 0.66 kPa, 2.13 ± 0.21 Pa.s). The difference between prostate cancer and prostatitis was statistically significant ( t = 19.392, p < 0.01; t = 16.372, p < 0.01). The elasticity and viscosity of the healthy peripheral zone of prostate were 2.26 ± 0.45 kPa, 2.38 ± 0.54 Pa.s, respectively. There also was significant difference in elasticity between prostate cancer and normal peripheral zone ( t = 25.136, p < 0.01). In addition, we observed a positive correlation between Gleason scores and elasticity of the prostate cancer ( r = 0.913, P < 0.01) in this study. Conclusion MR elastography can be used to visualize the difference in stiffness between prostate cancer and benign prostatic disease. It is a new imaging method with potential in the diagnosis of prostate cancer.