bluuebunny/crossref_metadata_2025 huggingface dataset:
Parallel Iterative Solution Schemes for the Analysis of Air Foil Bearings
Authors: Wang N. , Chang S.-H.
Published: August 2012

In an air foil bearing analysis the model is usually solved iteratively due in part to the nonlinearity of the modeling Reynolds equation and the compliance of the bearing surface. The solution procedure requires a multiple-level-deep nested iteration, which involves extended solution time and convergence difficulty. In this study, a simple air foil bearing model is used and the compressible-fluid Reynolds equation for modeling gas lubrication is linearized by Newton's method. The discretized equation is solved by one of the two parallel iterative methods, red-black or strip partition successive-over-relaxation (SOR) method. The parallel programming is conducted using OpenMP programming in an eight-core work-station. Then, a numerical damping scheme for the film-profile convergence is presented. Finally, a root-finding process is conducted to iteratively attain the eccentricity of the bearing for a given load. It is found that the numerical damping step is crucial, which allows the use of a larger relaxation factor to have a fast rate of convergence. Both the parallel SOR methods are easy to implement and the red-black SOR method exhibits better efficiency in the studied cases. This study presents a parallel computing scheme for analyzing air foil bearing of bump-type by today's shared-memory multicore platforms.
The Influence of Diameter-to-Thickness Ratios on the Response and Collapse of Sharp-Notched Circular Tubes under Cyclic Bending
Authors: Lee K.-L. , Hsu C.-M. , Pan W.-F.
Published: August 2012

This paper discusses an experimental investigation of the behavior of sharp-notched circular tubes subjected to cyclic bending. The sharp-notched circular tubes of 304 stainless steel with three different diameter-to-thickness ratios (Do / t) were tested under symmetric curvature-controlled cyclic bending. It has been shown that the moment-curvature curves exhibited the loops with cyclic hardening and gradually becoming steady after a few cycles for all tested tubes. The ovalization-curvature curves revealed unsymmetric, ratcheting and increasing behavior with the number of cycles. In addition, five almost parallel lines corresponding to five different notch depths for each Do / t ratio were found from the experimental relationship between the cyclic controlled curvature and the number of cycles necessary to produce buckling on a log-log scale. Finally, an empirical relationship was proposed so it could be used for simulating the aforementioned relationship. By comparing with the experimental finding, the derived empirical relationship was in good agreement with the experimental data.
Buckling Equations of Orthotropic Thin Plates
Authors: Kuo S.-R. , Yau J. D.
Published: August 2012

Conventionally, only three components of stress, i.e., the membrane stresses (1σxx, 1σyy, 1σxy) in x-y plane along span directions, are considered in deriving the buckling equations of thin plates using energy approaches. Of particular interest in this study is to take all the six components of stress into account in formulating the potential energy for an orthotropic plate. By invoking the conditions of stress equilibrium for the plate and Green's theorem to relate the potential energy to external virtual works, all the instability potential terms associated with the non-conventional stresses (1σxz, 1σyz, 1σzz) can either cancel those terms conventionally referred to as higher-order terms or combine with them to yield some new but meaningful terms. For this reason, the present approach contains more physical and compact meaning than conventional ones in the process of derivation. With the present governing differential equations, bending buckling problems of orthotropic rectangular plates will be investigated in this study.
Nurbs-Based Profile Reconstruction using Constrained Fitting Techniques
Authors: Imani B. M. , Hashemian S. A.
Published: August 2012

Ordered data point cloud obtained by laser-scanning, image processing or contact digitizing techniques is widely used for reconstructing a cross section profile in the field of reverse engineering. In this research, a comprehensive algorithm for reconstruction of 2D profile is developed based on NURBS parametric curve theory. In this regard, the line, arc and B-spline segments are firstly extracted from the set of ordered data points using a developed segment detection algorithm. Then, the final profile is reconstructed using the newly proposed algorithm of constrained local fitting which approximates these segments by NURBS curves with appropriate geometric continuity conditions. The validity, capability and functionality of the developed method are investigated by some practical case studies. Results show that developed algorithm can be integrated and improve the functionality of exiting reverse engineering systems.
THE DISCRETENESS OF SPECTRUM FOR HIGHER-ORDER DIFFERENTIAL OPERATORS IN WEIGHTED FUNCTION SPACES
Authors: ZHANG MAOZHU , SUN JIONG , AO JIJUN
Published: August 2012

In this paper we consider the discreteness of spectrum for higher-order differential operators in weighted function spaces. Using the method of embedding theorems of weighted Sobolev spaces Hnp in weighted spaces Ls,r, we obtain a new sufficient and necessary condition to ensure that the spectrum is discrete, which can be easily used to judge the discreteness of some differential operators.
Highly viscous guar gum shifts dietary amino acids from metabolic use to fermentation substrate in domestic cats
Authors: Rochus Kristel , Janssens Geert P. J. , Van de Velde Hannelore , Verbrugghe Adronie , Wuyts Birgitte , Vanhaecke Lynn , Hesta Myriam
Published: August 2012

The present study evaluated the potential of affecting amino acid metabolism through intestinal fermentation in domestic cats, using dietary guar gum as a model. Apparent protein digestibility, plasma fermentation metabolites, faecal fermentation end products and fermentation kinetics (exhaled breath hydrogen concentrations) were evaluated. Ten cats were randomly assigned to either guar gum- or cellulose-supplemented diets, that were fed in two periods of 5 weeks in a crossover design. No treatment effect was seen on fermentation kinetics. The apparent protein digestibility (P= 0·07) tended to be lower in guar gum-supplemented cats. As a consequence of impaired small-intestinal protein digestion and amino acid absorption, fermentation of these molecules in the large intestine was stimulated. Amino acid fermentation has been shown to produce high concentrations of acetic and butyric acids. Therefore, no treatment effect on faecal propionic acid or plasma propionylcarnitine was observed in the present study. The ratio of faecal butyric acid:total SCFA tended to be higher in guar gum-supplemented cats (P= 0·05). The majority of large-intestinal butyric acid is absorbed by colonocytes and metabolised to 3-hydroxy-butyrylcoenzyme A, which is then absorbed into the bloodstream. This metabolite was analysed in plasma as 3-hydroxy-butyrylcarnitine, which was higher (P= 0·02) in guar gum-supplemented cats. In all probability, the high viscosity of the guar gum supplement was responsible for the impaired protein digestion and amino acid absorption. Further research is warranted to investigate whether partially hydrolysed guar gum is useful to potentiate the desirablein vivoeffects of this fibre supplement.
Annual variations in body-size spectra of planktonic ciliate communities and their relationships to environmental conditions: a case study in Jiaozhou Bay, northern China
Authors: Xu Henglong , Jiang Yong , Zhang Wei , Zhu Mingzhuang , Al-Rasheid Khaled A. S. , Warren Alan
Published: August 2012

The annual variations in body-size spectra of planktonic ciliate communities and their relationships to environmental conditions were studied based on a 12-month dataset (June 2007 to May 2008) from Jiaozhou Bay on the Yellow Sea coast of northern China. Based on the dataset, the body sizes of the ciliates, expressed as equivalent spherical diameters, included five ranks: S1 (5–35 μm); S2 (35–55 μm); S3 (55–75 μm); S4 (75–100 μm); and S5 (100–350 μm). These body-size ranks showed a clear temporal succession of dominance in the order of S2 (January–April) → S1 (May–July) → S4 (August–September) → S3 (October–December). Multivariate analyses showed that the temporal variations in their body-size patterns were significantly correlated with changes in environmental conditions, especially water temperature, salinity, dissolved oxygen concentration (DO) and nutrients. In terms of abundance, rank S2 was significantly correlated with water temperature, DO and nutrients, whereas ranks S4 and S5 were correlated with the salinity and nutrients respectively (P < 0.05). These results suggest that the body-size patterns of planktonic ciliate communities showed a clear temporal pattern during an annual cycle and significantly associated with environmental conditions in marine ecosystems.
Association between anxiety but not depressive disorders and leukocyte telomere length after 2 years of follow-up in a population-based sample
Authors: Hoen P. W. , Rosmalen J. G. M. , Schoevers R. A. , Huzen J. , van der Harst P. , de Jonge P.
Published: August 2012

Background

Telomere length is considered an emerging marker of biological aging. Depression and anxiety are associated with excess mortality risk but the mechanisms remain obscure. Telomere length might be involved because it is associated with psychological distress and mortality. The aim of this study was to test whether anxiety and depressive disorders predict telomere length over time in a large population-based sample.

Method

All analyses were performed in a longitudinal study in a general population cohort of 974 participants. The Composite International Diagnostic Interview (CIDI) was used to measure the presence of anxiety and depressive disorders. Telomere length was measured using monochrome multiplex polymerase chain reaction (PCR) at approximately 2 years of follow-up. We used linear multivariable regression models to evaluate the association between anxiety and depressive disorders and telomere length, adjusting for adverse life events, lifestyle factors, educational level and antidepressant use.

Results

The presence of anxiety disorders predicted shorter telomeres at follow-up (β = –0.073,t = –2.302,p = 0.022). This association was similar after controlling for adverse life events, lifestyle factors, educational level and antidepressant use (β = –0.077,t = –2.144,p = 0.032). No association was found between depressive disorders and shorter telomeres at follow-up (β = 0.010,t = 0.315,p = 0.753).

Conclusions

This study found that anxiety disorders predicted shorter telomere length at follow-up in a general population cohort. The association was not explained by adverse life events, lifestyle factors, educational level and antidepressant use. How anxiety disorders might lead to accelerated telomere shortening and whether this might be a mediator explaining the excess mortality risk associated with anxiety deserve further investigation.
Estimating and managing blowout risk during access to subglacial Antarctic lakes
Authors: Brito Mario P. , Griffiths Gwyn , Mowlem Matthew , Makinson Keith
Published: August 2012

As Antarctic subglacial lake research progresses toin situexploration an important topic is the lake's probable gas concentration. Depending on hydrological setting, subglacial lakes may contain large amounts of dissolved gas or gas trapped within clathrates. Consequently, access can be potentially dangerous due to the risk of blowout where depressurization could lead to high-speed ejection of water and gas from a borehole. We present a structured approach to assess the blowout risk in subglacial lake exploration. The approach integrates a generic event tree, applicable to open and closed hydrological systems, with site-specific expert judgment incorporating rigorous probabilistic formulations. The methodology is applied to a motivating example: Ellsworth Subglacial Lake. Judgments elicited through a formal process were provided by five experts with 88 years combined experience that, after aggregation, gave a median risk of blowout of 1 in 2186 with a lower quartile of 1 in 3433 and an upper quartile of 1 in 1341. This approach can be applied to any subglacial lake given a modicum of knowledge on its hydrological setting, as uncertainty can be captured through the elicited judgments. Additionally, the event tree analysis informs blowout mitigation strategies to reduce risk of injury or death.
Intraosseous Access in the Prehospital Setting: Literature Review
Authors: Olaussen Alexander , Williams Brett
Published: August 2012

Background

Although the majority of Australian intensive care paramedics use the manual intraosseous infusion technique (MAN-IO), several other semiautomatic devices now are available, such as the bone injection gun (BIG) and the semiautomatic intraosseous infusion system (EZ-IO). Given the choice of devices now available, questions have been raised regarding success rates, accuracy, decay of skills, and adverse events.

Objectives

Review the literature regarding the use of intraosseous (IO) devices in the prehospital setting.

Methods

Selected electronic databases (Medline, Embase, and CINAHL) were searched, and a hand search was conducted for grey-literature that included studies from the commencement of the process to the end of May 2010. Inclusion criteria were any study reporting intraosseous insertion and/or infusion (adult and pediatric) by paramedics in the prehospital setting.

Findings

The search located 2,100 articles; 20 articles met the inclusion criteria. The review also noted that use of IO access (regardless of technique) offers a safe and simple method for gaining access to the patients’ vascular system. A number of studies found that the use of semiautomatic devices offers better and faster intraosseous access compared with the use of manual devices, and also were associated with fewer complications. The findings also suggest that the use of semiautomatic devices can reduce insertion times and the number of insertion attempts when contrasted with the use of manual insertion techniques. Despite these findings, statistically no specific IO device has proven clinical superiority.

Conclusion

While manual IO techniques currently are used by the majority of Australian paramedics, the currently available evidence suggests that semiautomatic devices are more effective. Further research, including cost-benefit analyses, is required at a national level to examine skill acquisition, adverse effects, and whether comparative devices offer clinically significant advantages.

OlaussenA,WilliamsB.Intraosseous access in the prehospital setting: literature review.Prehosp Disaster Med.2012;27(5):1-5.
Birth weight and obesity risk at first grade of high school in a non-concurrent cohort of Chilean children
Authors: Loaiza Susana , Atalah Eduardo
Published: August 2012

Objective

To determine the association of birth weight with obesity risk at first grade of high school in Chilean children after accounting for potential confounding factors.

Design

National non-concurrent cohort of newborns. Sociodemographic information, height, weight and anthropometric measurements at first grade of high school were analysed. Birth weight was classified as macrosomia (≥4000 g), by gestational age and by ponderal index. The relationship between birth weight and obesity at first grade of high school (BMI ≥ 95th percentile of the US Centers for Disease Control and Prevention's reference) was assessed using logistic regression models adjusted for sociodemographic information at delivery.

Setting

First grade of public high school of low and middle socio-economic status in the whole country (about 77 % of Chilean children in this age group).

Subjects

Newborns (n 119 070) and the same number of high-school students.

Results

A positive relationship of high ponderal index (OR = 1·86, 95 % CI 1·69, 2·03), birth weight ≥4000 g (OR = 1·66, 95 % CI 1·54, 1·78) and large for gestational age (OR = 1·69, 95 % CI 1·58, 1·81) with obesity at adolescence (P < 0·001) was found. Macrosomic children had a higher risk of being obese at first grade of high school after controlling for prenatal confounding variables (OR = 1·63, 95 % CI 1·52, 1·76; P < 0·001).

Conclusions

A direct relationship between high birth weight and obesity at first grade of high school was observed in this group of Chilean children. The results highlight the significance of birth weight as a simple tool to be used as an indicator of obesity risk for children by health-care providers.
An experimental study of the vertical travel accuracy of the treatment table used in radiotherapy
Authors: Riis Hans L. , Zimmermann Sune J.
Published: August 2012

The idea of the present work was to investigate general features of the vertical travel of the treatment table in different configurations and the limitations of an optimised alignment. The investigations were carried out on two tables for different load cases, lateral positions and turntable angles. A wire was held vertically nearby the rotational axis of the table. The wire was used as reference in the investigations. A digital USB-microscope was attached to the tabletop. An orthogonal set of images of the wire was acquired at different vertical table positions. By analysing the images the vertical travel accuracy of the table was extracted. The two tables were found to travel linearly with the same characteristics over the full range of 110 cm with deviations less than 0.5 mm relative to a straight line. A divergence from a vertical travel above 0.5 mm was found to originate from misalignment. An alignment procedure to attain the optimal vertical performance with a minimum of inclination was presented. This procedure must be relayed on objective measured data of the travel with uncertainties far beyond 0.5 mm. Our suggested experimental method was found to have the potential to obtain the required data.
Coordinative Advantages of State Resources under SNTV: The Case of Taiwan
Authors: BATTO NATHAN F. , KIM HENRY A.
Published: August 2012

Success in SNTV requires not merely winning but also coordinating votes. Governing parties often reap coordination advantage thanks to their control of the state and its resources. Since governing parties in authoritarian states enjoy greater control over the state and its resources, we argue that they should also enjoy magnified coordinative advantages in SNTV election. Of course, authoritarian regimes often use state resources to win more votes; we argue that, in SNTV, in addition to winning more votes, those votes can also be distributed more effectively. We demonstrate our claims using election data from both local and national SNTV elections in Taiwan from 1954 to 2005.
Twin–Singleton Differences in Intelligence: A Register-Based Birth Cohort Study of Norwegian Males
Authors: Eriksen Willy , Sundet Jon M. , Tambs Kristian
Published: August 2012

The aim was to determine the difference in intelligence between singletons and twins in young adulthood. Data from the Medical Birth Register of Norway were linked with register data from the Norwegian National Conscript Service. The study base consisted of data on the 445,463 males who were born alive in either single or twin births in Norway during 1967–1984 and who were examined at the time of the mandatory military conscription (age 18–20). Within this study base, there were data on 1,653 sibships of full brothers that included at least one man born in single birth and at least one man born in twin birth (4,307 persons, including 2,378 twins and 1,929 singletons). The intelligence scores of the singletons were 11% (95% confidence interval [CI]: 9–14%) of a standard deviation higher than those of the twins, after adjustment for birth year, birth order, parental ages at delivery, parental education levels, and other factors. The adjusted within-family difference was also 11% (95 % CI: 6–16%) of a standard deviation, indicating that unmeasured factors shared by siblings (e.g., maternal body height) have not influenced the estimate in important ways. When gestational age at birth was added to the model, the estimate for the difference in intelligence score was approximately the same. Including birth weight in the model strongly reduced the estimate. In conclusion, twins born in Norway during 1967–1984 had slightly lower intelligence in early adulthood compared with the singletons.
Diapycnal diffusivity at the upper boundary of the tropical North Atlantic oxygen minimum zone
Authors: Banyte Donata , Tanhua Toste , Visbeck Martin , Wallace Douglas W. R. , Karstensen Johannes , Krahmann Gerd , Schneider Anke , Stramma Lothar , Dengler Marcus
Published: August 2012

A deliberate tracer release experiment in 2008–2010 was used to study diapycnal mixing in the tropical northeastern Atlantic. The tracer (CF3SF5) was injected on the isopycnal surface σΘ = 26.88 kg m−3, which corresponds to about 330 m depth. Three surveys, performed 7, 20, and 30 months after the release, sampled the vertically and laterally expanding tracer patch. The mean diapycnal mixing estimate over the entire region occupied by the tracer and the period of 30 months was found to be (1.19 ± 0.18) × 10−5 m2 s−1, or, alternatively, (3.07 ± 0.58) × 10−11 (kg m−3)2 s−1as computed from the advection‐diffusion equation in isopycnal coordinates with the thickness‐weighted averaging. The latter method is preferable in the regions of different stratification for it yields local diapycnal mixing estimates varying less with stratification than their Cartesian coordinate counterparts. Results of this study are comparable to the results of the North Atlantic tracer release experiment (NATRE). However, the internal wave‐wave interaction models predict reduced mixing from the breaking of internal waves at low latitudes. Thus, the diapycnal diffusivity found in this study is higher than parameterized by the low latitude of the site (4°N–12°N).
Century to multi‐century sea level rise projections from CMIP5 models
Authors: Yin Jianjun
Published: August 2012

Long‐term projections of global‐ocean thermal expansion (GTE) and the dynamic sea level (DSL) change are analyzed with 34 new CMIP5 models and under three greenhouse‐gas emission scenarios. Multi‐model ensemble mean (MEM) and ensemble standard deviation are calculated to identify robust features and quantify uncertainty. While the MEM of GTE shows moderate difference by 2100, with magnitudes of 13, 18 and 28 cm in RCP2.6, RCP4.5 and RCP8.5, respectively, it increases and diverges significantly by 2300, with magnitudes of 21, 52 and 119 cm in the three scenarios. Model‐to‐model spread seems reduced in CMIP5 compared to CMIP3. The MEM changes of the DSL show similar patterns between different RCPs, but with progressively larger magnitudes in RCP2.6, RCP4.5 and RCP8.5. Notable features identified previously in the CMIP3 projections also occur in CMIP5, indicating their robustness across generations of climate model and emission scenario. The CMIP5 models still show disagreement in projecting the DSL changes, even under the same external forcing.
Daytime climatology of ionospheric NmF2 and hmF2 from COSMIC data
Authors: Burns A. G. , Solomon S. C. , Wang W. , Qian L. , Zhang Y. , Paxton L. J.
Published: August 2012

Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) data were analyzed to study the climatological variations of the F2 region ionosphere. A 30 day running median was applied to the daily medians of each geomagnetic latitude bin (100) to remove the short‐term variability of the data. This permitted a better description of the long‐term daytime climatology across the most recent solar minimum to be obtained. Several significant features appeared in this climatology: 1) low‐latitude NmF2 was dominated by the semi‐annual anomaly, the equatorial anomaly and the annual asymmetry (anomaly); 2) Semi‐annual and annual anomalies extended into the middle latitudes; 3) this extension into the middle latitudes appears to be dependent on variations of solar radiation over the solar cycle, as the variations did not reach as far poleward in 2008 as they did in 2010; 4) The second equinoctial maximum is not centered on the September equinox, but occurred in October; 5) there is an annual variation at high latitudes in which maximum values of NmF2 occur in summer – there is no indication of a winter anomaly and, in fact, when hemispheres are compared, maximum NmF2 at middle latitudes always occurs in the summer hemisphere rather than the winter one; 6) the highest values of hmF2 at low latitudes occur on the summer side of the magnetic equator throughout the four year period, probably resulting from winds blowing from the summer to the winter; 7) minimum values of hmF2 at middle latitudes occur in winter, when hmF2 is typically 30 to 50 km lower than it is in summer; 8) elevated hmF2 also occurs in summer at high latitudes, with a distinct seasonal and hemispheric asymmetry.
Observational evidence of Alfvén wings at the Earth
Authors: Chané E. , Saur J. , Neubauer F. M. , Raeder J. , Poedts S.
Published: August 2012

The solar wind at the orbit of the Earth is usually strongly super‐Alfvénic and super‐fast, causing a bow‐shock to be formed upstream of the Earth's magnetosphere. We here present observational evidence that during 24 and 25 May 2002, the solar wind at the Earth was sub‐Alfvénic (with an Alfvén Mach number as low as 0.4 in the rest frame of the Earth) and was therefore sub‐fast for time periods of up to four hours. The low Alfvén Mach number implies that the Earth's bow‐shock disappeared and two Alfvén wings formed. These Alfvén wings are two structures on both the East and West side of the Earth's magnetosphere, where the solar wind plasma is decelerated and the magnetic field direction changes. We present observations of the Geotail spacecraft, which are consistent with Geotail entering the foot of one of these Alfvén wings. We estimate that these wings reached an extension of 600 RE. Even though Alfvén wings are present at several moons in the solar system (e.g., Io, Europa, Enceladus) and are likely to occur at some extrasolar planets, this is the first time that they are observed at the Earth. We also study how the Earth is affected by this transition from a super‐fast to a sub‐Alfvénic environment and how the Alfvén wings are affected by the constantly varying solar wind. The sub‐Alfvénic solar wind is due to very low density in the solar wind. While the solar wind Alfvén Mach number was very low, the magnetosphere was geomagnetically extremely quiet. Whereas the SYM‐H index indicates a recovery phase from a small to moderate magnetic storm; the AL and AU indices show no substorm activity. In addition, there was almost no auroral activity.
Estimating surface energy fluxes using a dual‐source data assimilation approach adjoined to the heat diffusion equation
Authors: Bateni S. M. , Liang S.
Published: August 2012

Recently, a number of studies have assimilated land surface temperature (LST) within a variational data assimilation (VDA) framework to estimate turbulent heat fluxes. These VDA models have mainly considered soil and vegetation as a combined source (CS) and have not accounted for the difference between soil and canopy temperatures and turbulent exchange rates, although soil and canopy can exhibit very different behaviors. Hence, in this study the contribution of soil and canopy to the LST and turbulent heat fluxes is taken into account separately by developing a dual‐source (DS) VDA model. The unknown model parameters are the neutral bulk heat transfer coefficient (that scales the sum of turbulent heat fluxes) and the evaporative fractions for soil and canopy (which represent partitioning among the turbulent fluxes over soil and vegetation). The model as developed has been tested with area‐averaged measurements of turbulent heat fluxes obtained from the First International Satellite Land Surface Climatology Project Field Experiment (FIFE) during the summers of 1987 and 1988. The results show that the predicted turbulent heat fluxes match well with observations. For FIFE 1987 (1988), the half‐hourly latent heat flux estimates from the new model have a root‐mean square‐error (RMSE) of 57.4 Wm−2 (66.8 Wm−2), which represents a significant improvement over the previous study.
Examination of causative link between a spring bloom and dry/wet deposition of Asian dust in the Yellow Sea, China
Authors: Shi Jin‐Hui , Gao Hui‐Wang , Zhang Jing , Tan Sai‐Chun , Ren Jing‐Ling , Liu Cheng‐Gang , Liu Ying , Yao Xiaohong
Published: August 2012

Atmospheric deposition can deliver new nutrients to the surface water and support primary productivity. Here we report a phytoplankton bloom that developed in the Yellow Sea in the spring of 2007 3–4 days following a dust storm accompanied by precipitation. Our data indicate that atmospheric deposition dominated the supply of new nutrients to the surface water in the central Yellow Sea during the dust event. Dust‐derived nitrogen (N) supply was sufficient to support the observed phytoplankton growth, while, dust‐derived iron (Fe) supply far exceeded that required by the biota. Granger causality test results further supported that dust‐derived nutrients deposition was the cause for the observed bloom with a lag of 3–5 days. Our results contribute to the growing database linking phytoplankton blooms to atmospheric deposition derived fertilization effects. Both dry and wet deposition contributed nutrients to the surface ocean during this event; however, the nutrient loading from dry deposition alone was not sufficient to satisfy the demand of the phytoplankton in this bloom event.
DJ-1 promotes the proteasomal degradation of Fis1: implications of DJ-1 in neuronal protection
Authors: Zhang Qiang , Wu Junbing , Wu Rong , Ma Jun , Du Guiping , Jiao Renjie , Tian Yong , Zheng Zheng , Yuan Zengqiang
Published: August 2012

Mutations in DJ-1/PARK7 (Parkinson protein 7) have been identified as a cause of autosomal-recessive PD (Parkinson's disease) and the antioxidant property of DJ-1 has been shown to be involved in the regulation of mitochondrial function and neuronal cell survival. In the present study, we first found that the DJ-1 transgene mitigated MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-induced DA (dopamine) neuron cell death and cell loss. We then observed that the protein levels of DJ-1 were significantly decreased, whereas levels of Fis1 [fission 1 (mitochondrial outer membrane) homologue] were noticeably increased in the striatum of MPTP-treated mice. In addition to our identification of RNF5 (RING-finger protein-5) as an E3-ligase for Fis1 ubiquitination, we demonstrated the involvement of the DJ-1/Akt/RNF5 signalling pathway in the regulation of Fis1 proteasomal degradation. In other experiments, we found that Akt1 enhances the mitochondrial translocation and E3-ligase activity of RNF5, leading to Fis1 degradation. Together, the identification of Fis1 degradation by DJ-1 signalling in the regulation of oxidative stress-induced neuronal cell death supplies a novel mechanism of DJ-1 in neuronal protection with the implication of DJ-1 in a potential therapeutic avenue for PD.
Calpain-1 knockout reveals broad effects on erythrocyte deformability and physiology
Authors: Wieschhaus Adam , Khan Anwar , Zaidi Asma , Rogalin Henry , Hanada Toshihiko , Liu Fei , De Franceschi Lucia , Brugnara Carlo , Rivera Alicia , Chishti Athar H.
Published: August 2012

Pharmacological inhibitors of cysteine proteases have provided useful insights into the regulation of calpain activity in erythrocytes. However, the precise biological function of calpain activity in erythrocytes remains poorly understood. Erythrocytes express calpain-1, an isoform regulated by calpastatin, the endogenous inhibitor of calpains. In the present study, we investigated the function of calpain-1 in mature erythrocytes using our calpain-1-null [KO (knockout)] mouse model. The calpain-1 gene deletion results in improved erythrocyte deformability without any measurable effect on erythrocyte lifespan in vivo. The calcium-induced sphero-echinocyte shape transition is compromised in the KO erythrocytes. Erythrocyte membrane proteins ankyrin, band 3, protein 4.1R, adducin and dematin are degraded in the calcium-loaded normal erythrocytes but not in the KO erythrocytes. In contrast, the integrity of spectrin and its state of phosphorylation are not affected in the calcium-loaded erythrocytes of either genotype. To assess the functional consequences of attenuated cytoskeletal remodelling in the KO erythrocytes, the activity of major membrane transporters was measured. The activity of the K+–Cl− co-transporter and the Gardos channel was significantly reduced in the KO erythrocytes. Similarly, the basal activity of the calcium pump was reduced in the absence of calmodulin in the KO erythrocyte membrane. Interestingly, the calmodulin-stimulated calcium pump activity was significantly elevated in the KO erythrocytes, implying a wider range of pump regulation by calcium and calmodulin. Taken together, and with the atomic force microscopy of the skeletal network, the results of the present study provide the first evidence for the physiological function of calpain-1 in erythrocytes with therapeutic implications for calcium imbalance pathologies such as sickle cell disease.
SLP-76 is required for high-affinity IgE receptor- and IL-3 receptor-mediated activation of basophils
Authors: Hidano Shinya , Kitamura Daisuke , Kumar Lalit , Geha Raif S. , Goitsuka Ryo
Published: August 2012

Basophils have been reported to play a critical role in allergic inflammation by secreting IL-4 in response to IL-3 or high-affinity IgE receptor (FcεRI)-cross-linking. However, the signaling pathways downstream of FcεRI and the IL-3 receptor in basophils have yet to be determined. In the present study, we used mice deficient in SLP-76 (Src homology 2 domain-containing leukocyte phosphoprotein of 76kDa) to demonstrate critical functions of this adaptor molecule in transducing FcεRI- and IL-3 receptor-mediated signals that induce basophil activation. Although SLP-76 was dispensable for in vivo differentiation, as well as IL-3-induced in vitro proliferation of basophils, IL-4 production induced by both stimuli was completely ablated by SLP-76 deficiency. Biochemical analyses revealed that IL-3-induced phosphorylation of phospholipase C (PLC) γ2 and Akt, but not STAT5, was severely reduced in SLP-76-deficient basophils, whereas FcεRI cross-linking phosphorylation of PLCγ2, but not Akt, was abrogated by SLP-76 deficiency, suggesting important differences in the requirement of SLP-76 for Akt activation between FcεRI- and IL-3 receptor-mediated signaling pathways in basophils. Because IL-3-induced IL-4 production was sensitive to calcineurin inhibitors and an intracellular calcium chelator, in addition to PI3K inhibitors, SLP-76 appears to regulate FcεRI- and IL-3 receptor-induced IL-4 production via mediating PLCγ2 activation in basophils. Taken together, these findings indicate that SLP-76 is an essential signaling component for basophil activation downstream of both FcεRI and the IL-3 receptor.
Moesin-deficient mice reveal a non-redundant role for moesin in lymphocyte homeostasis
Authors: Hirata Takako , Nomachi Akira , Tohya Kazuo , Miyasaka Masayuki , Tsukita Sachiko , Watanabe Takeshi , Narumiya Shuh
Published: August 2012

Moesin is a member of the ezrin–radixin–moesin (ERM) family of cytoskeletal proteins. These proteins organize membrane domains by interacting with plasma membrane proteins and the actin cytoskeleton. Because of their high sequence similarity, ERM proteins are usually thought to be functionally redundant. Lymphocytes express two ERM proteins, ezrin and moesin. Whether each ERM plays a specialized role in lymphocytes, particularly in vivo, remains unknown. Here, we show that moesin has a crucial, non-redundant role in lymphocyte homeostasis. Moesin-deficient mice exhibited decreases in both T and B cells in the peripheral blood and lymph nodes, but not in the spleen. This phenotype was recapitulated in bone marrow (BM) chimeras with a hematopoietic moesin deficiency. Although the T and B cells apparently developed without major defects in the moesin-deficient mice, T cell egress from the thymus and immature B cell egress from the BM were impaired. In the periphery, both T and B cells showed delayed egress from lymphoid organs. We showed that moesin is the primary phosphorylated ERM subject to dynamic regulation during cell shape changes and migration. Our findings identify a previously unknown, non-redundant function of moesin in lymphocyte homeostasis in regulating lymphocyte egress from lymphoid organs.
Crystal structure of folliculin reveals a hidDENN function in genetically inherited renal cancer
Authors: Nookala Ravi K. , Langemeyer Lars , Pacitto Angela , Ochoa-Montaño Bernardo , Donaldson Jane C. , Blaszczyk Beata K. , Chirgadze Dimitri Y. , Barr Francis A. , Bazan J. Fernando , Blundell Tom L.
Published: August 2012

Mutations in the renal tumour suppressor protein, folliculin, lead to proliferative skin lesions, lung complications and renal cell carcinoma. Folliculin has been reported to interact with AMP-activated kinase, a key component of the mammalian target of rapamycin pathway. Most cancer-causing mutations lead to a carboxy-terminal truncation of folliculin, pointing to a functional importance of this domain in tumour suppression. We present here the crystal structure of folliculin carboxy-terminal domain and demonstrate that it is distantly related to differentially expressed in normal cells and neoplasia (DENN) domain proteins, a family of Rab guanine nucleotide exchange factors (GEFs). Using biochemical analysis, we show that folliculin has GEF activity, indicating that folliculin is probably a distantly related member of this class of Rab GEFs.
Viral mitochondria-localized inhibitor of apoptosis (UL37 exon 1 protein) does not protect human neural precursor cells from human cytomegalovirus-induced cell death
Authors: Hildreth Richard L. , Bullough Matthew D. , Zhang Aiping , Chen Hui-Ling , Schwartz Philip H. , Panchision David M. , Colberg-Poley Anamaris M.
Published: August 2012

Congenital human cytomegalovirus (HCMV) infection can cause severe brain abnormalities. Apoptotic HCMV-infected brain cells have been detected in a congenitally infected infant. In biologically relevant human neural precursor cells (hNPCs), cultured in physiological oxygen tensions, HCMV infection (m.o.i. of 1 or 3) induced cell death within 3 days post-infection (p.i.) and increased thereafter. Surprisingly, its known anti-apoptotic genes, including the potent UL37 exon 1 protein (pUL37x1) or viral mitochondria-localized inhibitor of apoptosis (vMIA), which protects infected human fibroblasts (HFFs) from apoptosis and from caspase-independent, mitochondrial serine protease-mediated cell death, were expressed by 2 days p.i. Consistent with this finding, an HCMV UL37x1 mutant, BADsubstitutionUL37x1 (BADsubUL37x1) induced cell death in hNPCs (m.o.i. = 1) to level which were indistinguishable from parental virus (BADwild-type)-infected hNPCs. Surprisingly, although BADsubUL37x1 is growth defective in permissive HFFs, it produced infectious progeny in hNPCs with similar kinetics and to levels comparable to BADwild-type-infected hNPCs (m.o.i. = 1). While delayed at a lower multiplicity (m.o.i. = 0.3), the BADsubUL37x1 mutant reached similar levels to revertant within 12 days, in contrast to its phenotype in HFFs. The inability of pUL37x1/vMIA to protect hNPCs from HCMV-induced cell death did not result from impaired trafficking as pUL37x1/vMIA trafficked efficiently to mitochondria in transfected hNPCs and in HCMV-infected hNPCs. These results establish that pUL37x1/vMIA, although protective in permissive HFFs, does not protect HCMV-infected hNPCs from cell death under physiologically relevant oxygen tensions. They further suggest that pUL37x1/vMIA is not essential for HCMV growth in hNPCs and has different cell type-specific roles.
Indications for a protective function of beta2‐glycoprotein I in thrombotic thrombocytopenic purpura
Authors: Du Vivian X. , van Os Gwen , Kremer Hovinga Johanna A. , Dienava‐Verdoold Ilze , Wollersheim Jacques , Ruggeri Zaverio M. , Fijnheer Rob , de Groot Philip G. , de Laat Bas
Published: August 2012

It has been shown that β2‐glycoprotein I (β2GPI) interacts with von Willebrand factor (VWF) in a glycoprotein (GP)Ib binding state. Given the presence of active VWF multimers in thrombotic thrombocytopenic purpura (TTP), we speculated that β2GPI might play a role in TTP. We found that β2GPI plasma levels were significantly lower in acute and remission TTP patients than in normal controls, showing a direct correlation with ADAMTS 13 levels and an inverse correlation with the extent of VWF activation. In vitro flow experiments demonstrated that β2GPI can block platelet adhesion to endothelial cell‐derived VWF strings. We confirmed the direct binding of β2GPI to VWF by surface plasmon resonance, and determined that domain I of β2GPI is the binding site of VWF A1 domain. Adhesion of β2GPI to erythrocytes and platelets was increased in the presence of active VWF, indicating that β2GPI may be cleared from the circulation during TTP episodes together with blood cells. Our findings suggest that β2GPI may protect from the effects of hyper‐functional VWF by inhibiting its interaction with platelets.
Salivary duct carcinomas can be classified into luminal androgen receptor‐positive, HER2 and basal‐like phenotypes*
Authors: Di Palma Silvana , Simpson Roderick H W , Marchiò Caterina , Skálová Alena , Ungari Marco , Sandison Ann , Whitaker Stephen , Parry Suzanne , Reis‐Filho Jorge S
Published: August 2012

Di Palma S, Simpson R H W, Marchiò C, Skálová A, Ungari M, Sandison A, Whitaker S, Parry S & Reis‐Filho J S  (2012) Histopathology 61, 629–643

Salivary duct carcinomas can be classified into luminal androgen receptor‐positive, HER2 and basal‐like phenotypes

Aims:  The aim of this study was to devise a molecular classification for salivary duct carcinomas (SDCs) based on the similarities between SDCs and breast carcinomas and on characteristics of the microarray‐based gene expression profiling‐defined molecular subtypes of breast cancer.

Methods and results:  Forty‐two pure salivary duct carcinomas, 35 of which contained an in‐situ component as defined by histological review and/or immunohistochemical analysis, were stained with antibodies for oestrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR) and cytokeratin (CK) 5/6. Based on these markers, tumours were classified into HER2, luminal androgen receptor‐positive, basal‐like, luminal and indeterminate phenotype. Analysis revealed that 16.7%, 69%, 4.8%, 9.5% and 0% were of HER2, luminal androgen receptor‐positive, basal‐like, indeterminate and luminal phenotype, respectively. The in‐situ and invasive components displayed the same molecular subtype in all but one case.

Conclusions:  Salivary duct carcinomas can be classified into molecular subgroups approximately equivalent to those in the breast. We also report on the existence of a subgroup of bona fide pure salivary duct carcinomas that have a ‘basal‐like’ phenotype. Understanding the phenotypic complexity of SDCs may help to expedite the identification of novel therapeutic targets for these aggressive tumours.
Adherence and medication management by the elderly
Authors: Henriques Maria A , Costa Maria A , Cabrita José
Published: August 2012

Aims and objectives.  The purpose of this study was to explore the strategies used for medication management by elderly who live at home.

Background.  Non‐adherence to chronic medication is a common problem among the elderly with chronic conditions. Many studies have been developed, but it did not progress in solving this multidisciplinary health care problem. The causes of non‐adherence by the elderly are multiple and complex.

Design.  Descriptive qualitative design.

Methods.  Data were collected by two focus groups. The content of discussion was analysed from verbatim transcript and identifying categories and sub‐categories emerged, leading to the construction of a diagram analysis.

Results.  The finding indicated the strategies and the interpretation of people aged 65 or more and with chronic illness, managing their medication. Four content categories emerged: to live with drugs, taking medication, belief about drugs and relationship with health professionals.

Conclusion.  The study enabled us to identify and understand, by giving a ‘voice’ to the elderly, that living with drugs is a dynamic and complex process and that taking medication is perceived by older people as a consequence of their ageing, which requires them to include that process in their lives as a habit implying changes in their daily routines. The elderly suggest that the relationship with health professionals is essential in medication management and they reported that the information given by the nurse during consultation is very important.

Relevance to clinical practice.  The relationship with nurses in particular is an important issue for the older people. Understanding the factors of adherence and helping people are important areas of research in nursing. The quality of this relationship may be the key to increasing adherence in this group of people.
Emotional loneliness is associated with mortality among mentally intact nursing home residents with and without cancer: a five‐year follow‐up study
Authors: Drageset Jorunn , Eide Geir E , Kirkevold Marit , Ranhoff Anette H
Published: August 2012

Aims and objectives.  Hypothesised that sociodemographic factors and illness variables would be associated with mortality and that emotional and social loneliness measured using the Social Provisions Scale would influence mortality among nursing homes residents with cancer.

Background.  Studies are lacking on how emotional and social loneliness influence mortality among cognitively intact older people in nursing homes with and without a diagnosis of cancer.

Design.  A cross‐sectional design was used at baseline with a five‐year follow‐up of mortality.

Methods.  A cohort of 227 cognitively intact (Clinical Dementia Rating scale score ≤0·5) older residents (60 with cancer and 167 without) from 30 nursing homes were followed from 2004–2005 to 2010. Data were collected by face‐to‐face interview. Sociodemographic variables and medical diagnoses were obtained from the records.

Results.  Survival did not differ significantly between residents with and without cancer. After adjustment for sociodemographic and illness variables, increasing age, higher education and comorbidity were associated with mortality. In the final model from a backward selection procedure, attachment (emotional loneliness) was associated with mortality.

Conclusions.  Independent of a cancer diagnosis or not, emotional loneliness, age, education and comorbidity influenced mortality among nursing homes residents without cognitive impairment.

Relevance to clinical practice.  Nurses should pay attention to emotional loneliness among nursing homes residents independent of cancer and especially give attention to the importance to have a close confidant who provides emotional support.