bluuebunny/crossref_metadata_2025 huggingface dataset:
Intrinsic slip on hydrophobic self-assembled monolayer coatings
Authors: Chinappi M. , Casciola C. M.
Published: April 2010

The slippage of liquids over solid surfaces is receiving a growing interest for its potential applications to microfluidic devices. Hydrophobic coatings of smooth surfaces have been reported able to induce a significant slip length. A considerable debate is found in the literature, and a substantial scatter in the measured slip lengths, ranging from zero to few microns, exists. Here we discuss a detailed molecular dynamics simulation of liquid water flowing over a self-assembled-monolayer of octadecyltrichlorosilane. The data provide a value of the slip length in the range of 0.2–0.6 nm, smaller than the most recent value of 20 nm obtained by means of an accurately controlled experiment with the surface force apparatus. The discrepancy between experiments and simulations is discussed, commenting on the possible effect of surface imperfections.
Nonlinear simulation of toroidal Alfvén eigenmode with source and sink
Authors: Lang Jianying , Fu Guo-Yong , Chen Yang
Published: April 2010

Kinetic/magnetohydrodynamic hybrid simulations are carried out to investigate the nonlinear dynamics of energetic particle-driven toroidal Alfvén eigenmode with collision and source/sink. For cases well above marginal stability, the mode saturation is approximately steady state with finite collision frequency. The calculated scaling of saturation level with collision frequency agrees well with analytic theory. For cases near-marginal stability at low collision rates, the mode saturation exhibits pulsation behavior with frequency chirps up and down.
On the design and implementation of a novel impedance chamber based variable temperature regulator at liquid helium temperatures
Authors: Nagendran R. , Thirumurugan N. , Chinnasamy N. , Janawadkar M. P. , Sundar C. S.
Published: April 2010

A novel variable temperature regulator (VTR) based on the use of a fine impedance capillary to control the flow rate of cold helium gas into the VTR chamber is described. The capillary has a diameter of just 200 μm and the flow rate of cold helium gas through the capillary can be effectively controlled to the desired value by heating the capillary to a preset temperature and by controlling the pressure in the VTR chamber to a preset pressure using automated control circuits. Excellent temperature stability (about ±1 mK at 10 K and ±2 mK at 100 K) has been demonstrated in this setup with uniform rates of heating or cooling by an optimal choice of parameters. Compared to the more conventional VTR designs based on the use of mechanical long stem valves in the liquid helium reservoir to control the flow rate of liquid helium into the VTR chamber, and the use of a needle valve at the top of the cryostat to control the exchange gas pressure in the thermal isolation chamber, the present design enables temperature stability at any user desired temperature to be attained with uniform rates of cooling/heating with minimum consumption of liquid helium. The VTR has been successfully incorporated in the high field superconducting quantum interference device magnetometer setup developed in-house. It can also be incorporated in any low temperature physical property measurement system in which the temperature has to be varied in a controlled manner from 4.2 to 300 K and vice versa with uniform rates of heating and cooling.
The electric field enhancements by single-walled carbon nanotubes in In2S3/In2O3 photoelectrochemical solar cells
Authors: Lee Jungwoo , Lee Wonjoo , Park Eunkyung , Park Taehee , Nah Yoon-Chae , Han Sung-Hwan , Yi Whikun
Published: April 2010

Using reverse-field emission (FE) current measurements, we demonstrate enhancement of the electric field by single-walled carbon nanotubes (SWNTs) in In2S3/In2O3 photoelectrochemical solar cells (PECs). In reverse-FE measurements, anode and cathode consists of In2S3/In2O3/(with or without) SWNTs on indium-doped tin oxide substrate and microtexturized tip silicon, respectively. The enhanced FE results for In2S3/In2O3/SWNTs show an electric field approximately two times more than In2S3/In2O3. The β value (i.e., electric field enhancement factor) of In2S3/In2O3 PECs with SWNT layers is 4950, which is ∼35.2% higher than that of In2S3/In2O3 PECs without SWNTs (3660). In PECs, the enhanced electric field intensifies the power of electron transfer, which accelerates the electron transfer rate in the cell.
Cantilever deflection measurement and actuation by an interdigitated transducer
Authors: Strambini E. , Piazza V. , Pingue P. , Biasiol G. , Sorba L. , Beltram F.
Published: April 2010

A scheme that allows all-electrical high-bandwidth readout of a cantilever deflection by means of an integrated interdigitated transducer is presented. The present approach takes advantage of the piezoelectricity of the chosen cantilever substrate material to generate and detect surface-acoustic-waves by means of an interdigitated transducer (IDT) and to determine cantilever deflections. We shall also show that the same IDT can be used to excite the oscillation modes of the lever. Our scheme is compatible with implementations exploiting wireless excitation and readout and in mass sensing applications.
Switching operation of lasing wavelength in mid-infrared ridge-waveguide quantum cascade lasers coupled with microcylindrical cavity
Authors: Wakayama Y. , Iwamoto S. , Arakawa Y.
Published: April 2010

We demonstrated switching operation of lasing wavelength in GaAs-based mid-infrared coupled-cavity quantum cascade lasers. Our cavity structures consist of a ridge-waveguide Fabry–Perot cavity coupled with a microcylindrical cavity. Individual control of currents injected into both cavities enabled single-mode operation and facilitated intentional mode switching between coupled-cavity modes with spacing over 120 nm. The integrated microcylindrical cavity expanded the separation of coupled-cavity modes due to the small size of the cavity and enabled switching the lasing wavelength over a wide spectral range.
Electrohydrodynamic instability of a charged liquid jet in the presence of an axial magnetic field
Authors: Ruo An-Cheng , Chang Min-Hsing , Chen Falin
Published: April 2010

Electrified liquid jets subjected to electrical destabilizing mechanisms often deform asymmetrically, creating an uncontrollable random motion that prevents the formation of uniform drops or organized microstructures. Employing a magnetic field is a potentially effective method of inhibiting the onset of unstable motion. This paper develops a theoretical model to investigate the effect of an axial magnetic field on the instability of a charged liquid jet. To demonstrate the stabilizing ability of this approach, this study uses temporal linear stability analysis to manifest the magnetic effect in various parameter domains including the Rayleigh regime, the atomization zone, and the bending instability for a viscous jet. Results show that the magnetic force induced by the motion of charged surface is insignificant in comparison with the electric force and does not have effect on the instability of a dielectric liquid jet. However, for a liquid with high electrical conductivity, the Lorentz force induced by a conducting current becomes significant, suppressing destabilizing mechanisms and substantially improving jet stability. In the atomization zone, the effect of magnetic inhibition is relatively limited because the imposed axial magnetic field does not affect long-wave nonaxisymmetric disturbances.
Depth variation of energy transport in fluid gravity waves
Authors: Isberg Jan , Engström Jens , Leijon Mats
Published: April 2010

We calculate the distribution of energy flux as a function of the distance below the surface for propagating polychromatic gravity fluid surface waves. Linear theory has been used to derive closed-form expressions for the energy flux as a function of depth. In this context we discuss the power distribution for real ocean waves measured off the west coast of Sweden and compare this to the energy flux distribution for waves with Pierson–Moskowitz and Bretschneider spectral distributions. This is done in order to get an improved understanding of how to improve the power absorption in wave energy converters, and this is also discussed in this paper.
Selected pro-inflammatory factor transcripts in bovine endometrial epithelial cells are regulated during the oestrous cycle and elevated in case of subclinical or clinical endometritis
Authors: Fischer Claudia , Drillich Marc , Odau Simone , Heuwieser Wolfgang , Einspanier Ralf , Gabler Christoph
Published: April 2010

Endometrial cells take part in embryo–maternal communication, as well as supporting the immune system in defending against invading pathogens. The aim of the present study was to examine the mRNA expression of factors that have been suggested to be involved in both events in the bovine endometrial epithelium, namely bovine granulocyte chemotactic protein 2 (CXCL5), interleukin-1 beta (IL1B), IL6, IL8, tumour necrosis factor (TNF), cyclooxygenase 2 (PTGS2) and haptoglobin (HP). Samples were collected in vivo from cows on Days 21–27 postpartum by the cytobrush method to evaluate the correlation between inflammatory factors and uterine health (cows with signs of clinical or subclinical endometritis and healthy cows). Bovine uteri were collected at the abattoir to investigate oestrous cycle-dependent mRNA expression patterns. Real-time reverse transcription–polymerase chain reaction revealed that the expression of CXCL5, IL1B, IL8 and TNF mRNA was significantly higher in cows with subclinical or clinical endometritis compared with healthy cows. The expression of CXCL5, IL1B and IL8 mRNA was increased around ovulation compared with the luteal phase. There was no indication of either oestrous cycle-dependent expression or a correlation with uterine health for IL6, PTGS2 and HP transcripts. These results suggest that CXCL5, IL1B, IL8 and TNF may represent potential marker genes for the detection of cows with subclinical endometritis and for monitoring new therapeutic approaches.
Mechanisms contributing to the reduced developmental competence of glucosamine-exposed mouse oocytes
Authors: Schelbach Cheryl J. , Kind Karen L. , Lane Michelle , Thompson Jeremy G.
Published: April 2010

Glucosamine (GlcN) is a widely used hyperglycaemia mimetic because of its ability to upregulate the ‘energy-sensing’ hexosamine biosynthesis pathway in a dose-dependent manner. A previous study demonstrated that addition of GlcN (2.5–5 mM) during IVM of cattle and pig cumulus–oocyte complexes (COC) inhibited development following fertilisation and early cleavage. In the present study, we demonstrate that the addition of 2.5 mM GlcN during IVM of mouse COCs similarly inhibits embryo development, with the degree of inhibition dependent upon the availability of glucose in the maturation medium. Furthermore, we determined that the effect of GlcN is likely mediated by the cumulus cell vestment, because we failed to observe inhibitory effects of GlcN following maturation of denuded (and therefore already developmentally compromised) oocytes. As with cattle oocytes, inhibition of O-linked glycosylation of unknown proteins within mouse cumulus cells significantly reversed the effects of GlcN. Finally, we also provide preliminary evidence that GlcN may inhibit the pentose phosphate metabolic pathway within the oocyte, an effect possibly mediated by cumulus cells in intact COCs. Collectively, our results demonstrate that GlcN inhibits the developmental competence of IVM mouse oocytes and suggest that this occurs via cumulus cell-mediated mechanisms. Therefore, the in vitro addition of GlcN is a useful experimental tool to determine the mechanisms of hyperglycaemic responses within COCs.
Targeted deletion of the Nesp55 DMR defines another
Gnas
imprinting control region and provides a mouse model of autosomal dominant PHP-Ib
Authors: Fröhlich Leopold F. , Mrakovcic Maria , Steinborn Ralf , Chung Ung-Il , Bastepe Murat , Jüppner Harald
Published: April 2010

Approximately 100 genes undergo genomic imprinting. Mutations in fewer than 10 imprinted genetic loci, including
GNAS,
are associated with complex human diseases that differ phenotypically based on the parent transmitting the mutation. Besides the ubiquitously expressed Gsα, which is of broad biological importance,
GNAS
gives rise to an antisense transcript and to several Gsα variants that are transcribed from the nonmethylated parental allele. We previously identified two almost identical
GNAS
microdeletions extending from exon NESP55 to antisense (AS) exon 3 (delNESP55/delAS3-4). When inherited maternally, both deletions are associated with erasure of all maternal
GNAS
methylation imprints and autosomal-dominant pseudohypoparathyroidism type Ib, a disorder characterized by parathyroid hormone–resistant hypocalcemia and hyperphosphatemia. As for other imprinting disorders, the mechanisms resulting in abnormal
GNAS
methylation are largely unknown, in part because of a paucity of suitable animal models. We now showed in mice that deletion of the region equivalent to delNESP55/delAS3-4 on the paternal allele (ΔNesp55
p
) leads to healthy animals without
Gnas
methylation changes. In contrast, mice carrying the deletion on the maternal allele (ΔNesp55
m
) showed loss of all maternal
Gnas
methylation imprints, leading in kidney to increased 1A transcription and decreased Gsα mRNA levels, and to associated hypocalcemia, hyperphosphatemia, and secondary hyperparathyroidism. Besides representing a murine autosomal-dominant pseudohypoparathyroidism type Ib model and one of only few animal models for imprinted human disorders, our findings suggest that the Nesp55 differentially methylated region is an additional principal imprinting control region, which directs
Gnas
methylation and thereby affects expression of all maternal
Gnas
-derived transcripts.
TIME SPENT WORKING
Authors: Boye Katarina
Published: April 2010

This study examines the connection between the time that women and men spend on paid work and housework and psychological distress, and addresses the question whether gender differences in time spent on these activities account for the gender difference in psychological distress. A group (n =1,277) of employed and cohabiting women and men from the Swedish Level-of-Living Survey 2000 (LNU 2000) are analysed using OLS regression. Results show that time spent on housework explains part of the gender difference in psychological distress. Among women, paid working time and possibly time spent on housework are associated with low psychological distress. However, spending too much time on one role decreases the possible beneficial effect of the other, and this is mainly caused by the resulting increase in total role time. Men's level of psychological distress is not associated with hours of paid work or housework. The study also shows that the division of housework between women and men is unusually uneven in households where women have a long total role time. Thus, an increase in men's participation in housework could decrease the gender difference in psychological distress as well as the number of women experiencing a high workload.
Negative Potentials Across Biological Membranes Promote Fusion by Class II and Class III Viral Proteins
Authors: Markosyan Ruben M. , Cohen Fredric S.
Published: April 2010

Voltage was investigated as a factor in the fusion of virions. Virions, pseudotyped with a class II, SFV E1 or VEEV E, or a class III protein, VSV G, were prepared with GFP within the core and a fluorescent lipid. This allowed both hemifusion and fusion to be monitored. Voltage clamping the target cell showed that fusion is promoted by a negative potential and hindered by a positive potential. Hemifusion occurred independent of polarity. Lipid dye movement, in the absence of content mixing, ceased before complete transfer for positive potentials, indicating that reversion of hemifused membranes into two distinct membranes is responsible for voltage dependence and inhibition of fusion. Content mixing quickly followed lipid dye transfer for a negative potential, providing a direct demonstration that hemifusion induced by class II and class III viral proteins is a functional intermediate of fusion. In the hemifused state, virions that fused exhibited slower lipid transfer than did nonfusing virions. All viruses with class II or III fusion proteins may utilize voltage to achieve infection.
Peroxisomal Membrane Proteins Insert into the Endoplasmic Reticulum
Authors: van der Zand Adabella , Braakman Ineke , Tabak Henk F.
Published: April 2010

We show that a comprehensive set of 16 peroxisomal membrane proteins (PMPs) encompassing all types of membrane topologies first target to the endoplasmic reticulum (ER) in Saccharomyces cerevisiae. These PMPs insert into the ER membrane via the protein import complexes Sec61p and Get3p (for tail-anchored proteins). This trafficking pathway is representative for multiplying wild-type cells in which the peroxisome population needs to be maintained, as well as for mutant cells lacking peroxisomes in which new peroxisomes form after complementation with the wild-type version of the mutant gene. PMPs leave the ER in a Pex3p-Pex19p–dependent manner to end up in metabolically active peroxisomes. These results further extend the new concept that peroxisomes derive their basic framework (membrane and membrane proteins) from the ER and imply a new functional role for Pex3p and Pex19p.
Brain-derived Neurotrophic Factor Regulates Satellite Cell Differentiation and Skeltal Muscle Regeneration
Authors: Clow Charlene , Jasmin Bernard J.
Published: April 2010

In adult skeletal muscle, brain-derived neurotrophic factor (BDNF) is expressed in myogenic progenitors known as satellite cells. To functionally address the role of BDNF in muscle satellite cells and regeneration in vivo, we generated a mouse in which BDNF is specifically depleted from skeletal muscle cells. For comparative purposes, and to determine the specific role of muscle-derived BDNF, we also examined muscles of the complete BDNF−/−mouse. In both models, expression of the satellite cell marker Pax7 was significantly decreased. Furthermore, proliferation and differentiation of primary myoblasts was abnormal, exhibiting delayed induction of several markers of differentiation as well as decreased myotube size. Treatment with exogenous BDNF protein was sufficient to rescue normal gene expression and myotube size. Because satellite cells are responsible for postnatal growth and repair of skeletal muscle, we next examined whether regenerative capacity was compromised. After injury, BDNF-depleted muscle showed delayed expression of several molecular markers of regeneration, as well as delayed appearance of newly regenerated fibers. Recovery of wild-type BDNF levels was sufficient to restore normal regeneration. Together, these findings suggest that BDNF plays an important role in regulating satellite cell function and regeneration in vivo, particularly during early stages.
Evaluating the Impact of a Pragmatic Nutrition Awareness Program for Expectant Mothers upon Birth Weight of the Newborn
Authors: Rastogi Sanjeev , Rastogi Ranjana , Rastogi Devesh , Rastogi Rajiv , Singh Girish , Chiappelli Francesco
Published: April 2010

Poor maternal nutritional status and substandard antenatal care, which result in increased women′s risk, low birth weight and stillbirth, afflict many countries with weak or emerging economies even today. Studies that address the effect of extending nutrition awareness among pregnant women to the net outcome of pregnancy remain scarce. We aimed to compare and contrast the effect of a pragmatic nutrition awareness program for expectant mothers (NAPEM) on birth weight of the newborn with a control group who received no such nutrition awareness activity. The effect of variables of mode of newborn delivery, associated complications at birth, and APGAR score of the newborn were also assessed. A pragmatic intervention trial of an antenatal care (ANC) program that consisted in nutrition awareness was conducted involving 53 pregnant women. Awareness was given through one‐to‐one interview and through informational literature provided to the participants in the local language. A hospital registry for deliveries undertaken during the study period was screened for identification of variables. A control group of matched pregnant women (n = 53) was obtained from the same hospital registry from preceding years, when the nutrition awareness program was not executed. A statistically significant improvement in birth weight of the newborn was observed in the intervention group, where expectant mothers were made aware about desired nutrition during pregnancy. A reduced incidence of complications associated with pregnancy was also observed in the intervention group. Providing awareness about nutritional requirements during pregnancy and suggesting the pragmatic ways to meet them was shown to be one possible effective measure to deal with pregnancy‐related undernutrition. We show the efficacy of the intervention for underprivileged regions of India marked by inadequate health care delivery and lower socio‐economical standards. We discuss our findings in the context of available evidence‐based guidelines.
Stock assessment and projections incorporating discard estimates in some years: an application to the hake stock in ICES Divisions VIIIc and IXa
Authors: Fernández C. , Cerviño S. , Pérez N. , Jardim E.
Published: April 2010

Fernández, C., Cerviño, S., Pérez, N., and Jardim, E. 2010. Stock assessment and projections incorporating discard estimates in some years: an application to the hake stock in ICES Divisions VIIIc and IXa. – ICES Journal of Marine Science, 67: 1185–1197. A Bayesian age-structured stock assessment model is developed to take into account available information on discards and to handle gaps in the time-series of discard estimates. The model incorporates mortality attributable to discarding, and appropriate assumptions about how this mortality may change over time are made. The result is a stock assessment that accounts for information on discards while, at the same time, producing a complete time-series of discard estimates. The method is applied to the hake stock in ICES Divisions VIIIc and IXa, for which the available data indicate that some 60% of the individuals caught are discarded. The stock is fished by Spain and Portugal, and for each country, there are discard estimates for recent years only. Moreover, the years for which Portuguese estimates are available are only a subset of those with Spanish estimates. Two runs of the model are performed; one assuming zero discards and another incorporating discards. When discards are incorporated, estimated recruitment and fishing mortality for young (discarded) ages increase, resulting in lower values of the biological reference points Fmax and F0.1 and, generally, more optimistic future stock trajectories under F-reduction scenarios.
Frank William Ernest Gibson. 22 July 1923 — 11 July 2008
Authors: Pittard A. J. , Cox G. B.
Published: April 2010

Frank Gibson rose from humble beginnings to become one of the most respected bacterial physiologists of his era. His identification of the elusive branch-point compound in the pathway of aromatic biosynthesis served as an initiation point for a sustained period of investigation in which the genes, enzymes and intermediates in the various pathways to phenylalanine and tyrosine, the quinones, enterochelin and 4-aminobenzoate were identified and examined in detail. studies on the function of ubiquinone led to an examination of oxidative phosphorylation and to the F
1
F
0
-ATPase of the bacterium
Escherichia coli
. With Graeme Cox he established a group of researchers who in the 1980s applied the various techniques of microbial genetics to construct a molecular profile of the proteins, which constituted the F
0
membrane- embedded part of the F
1
F
0
-ATPase. This work resulted in the formulation in 1986 of a rotational model and the identification of several residues that could comprise a pore through which the protons, which drove the rotation, could pass. He trained many research students during his lifetime and was an exemplary role model. Outside the laboratory he lived a full life, being an ardent skier, scuba diver and tennis player to name but a few of his pursuits. He is survived by his wife Robin and their son, Mark; by Frances, the daughter from his first marriage; and by grandchildren Teresa, Luke and Simon. His first wife, Margaret, and their second daughter, Ruth (mother of Teresa, Luke and Simon), are both deceased.
Health in financial crises: economic recession and tuberculosis in Central and Eastern Europe
Authors: Arinaminpathy Nimalan , Dye Christopher
Published: April 2010

The ongoing global financial crisis, which began in 2007, has drawn attention to the effect of declining economic conditions on public health. A quantitative analysis of previous events can offer insights into the potential health effects of economic decline. In the early 1990s, widespread recession across Central and Eastern Europe accompanied the collapse of the Soviet Union. At the same time, despite previously falling tuberculosis (TB) incidence in most countries, there was an upsurge of TB cases and deaths throughout the region. Here, we study the quantitative relationship between the lost economic productivity and excess TB cases and mortality. We use the data of the World Health Organization for TB notifications and deaths from 1980 to 2006, and World Bank data for gross domestic product. Comparing 15 countries for which sufficient data exist, we find strong linear associations between the lost economic productivity over the period of recession for each country and excess numbers of TB cases (r2= 0.94,p< 0.001) and deaths (r2= 0.94,p< 0.001) over the same period. If TB epidemiology and control are linked to economies in 2009 as they were in 1991 then the Baltic states, particularly Latvia, are now vulnerable to another upturn in TB cases and deaths. These projections are in accordance with emerging data on drug consumption, which indicate that these countries have undergone the greatest reductions since the beginning of 2008. We recommend close surveillance and monitoring during the current recession, especially in the Baltic states.
Why do insects have such a high density of flow-sensing hairs? Insights from the hydromechanics of biomimetic MEMS sensors
Authors: Casas Jérôme , Steinmann Thomas , Krijnen Gijs
Published: April 2010

Insects and arachnids are often quite hairy. The reasons for this high density of sensory hairs are unknown. Previous studies have predicted strong hydrodynamic coupling between densely packed airflow-sensitive hairs. Flow perturbation owing to single hairs and between tandem hairs, however, has never been experimentally measured. This paper aims to quantify the extent of flow perturbation by single and tandem hairs directly, using biomimetic microelectromechanical system (MEMS) hairs as physical models and particle image velocimetry (PIV) for flow visualization. Single and tandem MEMS hairs of varying interhair distances were subjected to oscillatory flows of varying frequency. Decreasing hair-to-hair distance markedly reduced flow velocity amplitude and increased the phase shift between the far-field flow and the flow between hairs. These effects were stronger for lower flow frequencies. We predict strong hydrodynamic coupling within whole natural hair canopies exposed to natural stimuli, depending on arthropod and hair sizes, and hair density. Thus, rather than asking why arthropods have so many hairs, it may be useful to address why hairs are packed together at such high densities, particularly given the exquisite sensitivity of a single hair.
Mutualism favours higher host specificity than does antagonism in plant–herbivore interaction
Authors: Kawakita Atsushi , Okamoto Tomoko , Goto Ryutaro , Kato Makoto
Published: April 2010

Coevolved mutualisms often exhibit high levels of partner specificity. Obligate pollination mutualisms, such as the fig–fig wasp and yucca–yucca moth systems, represent remarkable examples of such highly species-specific associations; however, the evolutionary processes underlying these patterns are poorly understood. The prevailing hypothesis suggests that the high degree of specificity in pollinating seed parasites is the fortuitous result of specialization in their ancestors because these insects are derived from endophytic herbivores that are themselves highly host-specific. Conversely, we show that in theGlochidion–Epicephalaobligate pollination mutualism, pollinators are more host-specific than are closely related endophytic leaf-feeding taxa, which co-occur withEpicephalaon the sameGlochidionhosts. This difference is probably not because of shifts in larval diet (i.e. from leaf- to seed-feeding), because seed-eating lepidopterans other thanEpicephalado not show the same degree of host specificity asEpicephala. Species of a tentative sister group ofEpicephalaeach attack several distantly related plants, suggesting that the evolution of strict host specificity is tied to the evolution of pollinator habit. These results suggest that mutualists can attain higher host specificity than that of their parasitic ancestors and that coevolutionary selection can be a strong promoter of extreme reciprocal specialization in mutualisms.
Influence of weather conditions on the flight of migrating black storks
Authors: Chevallier D. , Handrich Y. , Georges J.-Y. , Baillon F. , Brossault P. , Aurouet A. , Le Maho Y. , Massemin S.
Published: April 2010

This study tested the potential influence of meteorological parameters (temperature, humidity, wind direction, thermal convection) on different migration characteristics (namely flight speed, altitude and direction and daily distance) in 16 black storks (Ciconia nigra). The birds were tracked by satellite during their entire autumnal and spring migration, from 1998 to 2006. Our data reveal that during their 27-day-long migration between Europe and Africa (mean distance of 4100 km), the periods of maximum flight activity corresponded to periods of maximum thermal energy, underlining the importance of atmospheric thermal convection in the migratory flight of the black stork. In some cases, tailwind was recorded at the same altitude and position as the birds, and was associated with a significant rise in flight speed, but wind often produced a side azimuth along the birds' migratory route. Whatever the season, the distance travelled daily was on average shorter in Europe than in Africa, with values of 200 and 270 km d−1, respectively. The fastest instantaneous flight speeds of up to 112 km h−1were also observed above Africa. This observation confirms the hypothesis of thermal-dependant flight behaviour, and also reveals differences in flight costs between Europe and Africa. Furthermore, differences in food availability, a crucial factor for black storks during their flight between Europe and Africa, may also contribute to the above-mentioned shift in daily flight speeds.
Rural–urban gradient in seasonal forcing of measles transmission in Niger
Authors: Ferrari Matthew J. , Djibo Ali , Grais Rebecca F. , Bharti Nita , Grenfell Bryan T. , Bjornstad Ottar N.
Published: April 2010

Seasonally driven cycles of incidence have been consistently observed for a range of directly transmitted pathogens. Though frequently observed, the mechanism of seasonality for directly transmitted human pathogens is rarely well understood. Despite significant annual variation in magnitude, measles outbreaks in Niger consistently begin in the dry season and decline at the onset of the seasonal rains. We estimate the seasonal fluctuation in measles transmission rates for the 38 districts and urban centres of Niger, from 11 years of weekly incidence reports. We show that transmission rates are consistently in anti-phase to the rainfall patterns across the country. The strength of the seasonal forcing of transmission is not correlated with the latitudinal rainfall gradient, as would be expected if transmission rates were determined purely by environmental conditions. Rather, seasonal forcing is correlated with the population size, with larger seasonal fluctuation in more populous, urban areas. This pattern is consistent with seasonal variation in human density and contact rates due to agricultural cycles. The stronger seasonality in large cities drives deep inter-epidemic troughs and results in frequent local extinction of measles, which contrasts starkly to the conventional observation that large cities, by virtue of their size, act as reservoirs of measles.
Cost‐effectiveness of carbon ion radiation therapy for locally recurrent rectal cancer
Authors: Mobaraki Abdulelah , Ohno Tatsuya , Yamada Shigeru , Sakurai Hideyuki , Nakano Takashi
Published: April 2010

The aim of this study was to evaluate the cost‐effectiveness of carbon ion radiotherapy compared with conventional multimodality therapy in the treatment of patients with locally recurrent rectal cancer. Direct costs for diagnosis, recurrent treatment, follow‐up, visits, supportive therapy, complications, and admission were computed for each individual using a sample of 25 patients presenting with local recurrent rectal cancer at the National Institute of Radiological Science (NIRS) and Gunma University Hospital (GUH). Patients received only radical surgery for primary rectal adenocarcinoma and had isolated unresectable pelvic recurrence. Fourteen and 11 patients receiving treatment for the local recurrence between 2003 and 2005 were followed retrospectively at NIRS and GUH, respectively. Treatment was carried out with carbon ion radiotherapy (CIRT) alone at NIRS, while multimodality therapy including three‐dimensional conformal radiotherapy, chemotherapy, and hyperthermia was performed at GUH. The 2‐year overall survival rate was 85% and 55% for CIRT and multimodality treatment, respectively. The mean cost was ¥4 803 946 for the CIRT group and ¥4 611 100 for the multimodality treatment group. The incremental cost‐effectiveness ratio for CIRT was ¥6428 per 1% increase in survival. The median duration of total hospitalization was 37 days for CIRT and 66 days for the multimodality treatment group. In conclusion, by calculating all direct costs, CIRT was found to be a potential cost effective treatment modality as compared to multimodality treatment for locally recurrent rectal cancer. (Cancer Sci 2010)
Multilineage differentiation of dental follicle cells and the roles of Runx2 over‐expression in enhancing osteoblast/cementoblast‐related gene expression in dental follicle cells
Authors: Pan K. , Sun Q. , Zhang J. , Ge S. , Li S. , Zhao Y. , Yang P.
Published: April 2010

Objectives:  Dental follicle cells (DFCs) provide the origin of periodontal tissues, and Runx2 is essential for bone formation and tooth development. In this study, pluripotency of DFCs was evaluated and effects of Runx2 on them were investigated.

Materials and methods:  The DFCs were induced to differentiate towards osteoblasts, adipocytes or chondrocytes, and alizarin red staining, oil red O staining or alcian blue staining was performed to reveal the differentiated states. Bone marrow stromal cells (BMSCs) and primary mouse fibroblasts served as controls. DFCs were also infected with recombinant retroviruses encoding either full‐length Runx2 or mutant Runx2 without the VWRPY motif. Western blot analysis, real‐time real time RT‐PCR and in vitro mineralization assay were performed to evaluate the effects of full‐length Runx2 or mutant Runx2 on osteogenic/cementogenic differentiation of the cells.

Results:  The above‐mentioned staining methods demonstrated that DFCs were successfully induced to differentiate towards osteoblasts, adipocytes or chondrocytes respectively, confirming the existence of pluripotent mesenchymal stem cells in dental follicle tissues. However, staining intensity in DFC cultures was weaker than in BMSC cultures. Real‐time PCR analysis indicated that mutant Runx2 induced a more pronounced increase in expression levels of OC, OPN, Col I and CP23 than full‐length Runx2. Mineralization assay also showed that mutant Runx2 increased mineralization nodule formation more prominently than full‐length Runx2.

Conclusions:  Multipotent DFCs can be induced to differentiate towards osteoblasts, adipocytes or chondrocytes in vitro. Runx2 over‐expression up‐regulated expression levels of osteoblast/cementoblast‐related genes and in vitro enhanced osteogenic differentiation of DFCs. In addition, mutant Runx2‐induced changes in DFCs were more prominent than those induced by full‐length Runx2.
Cell proliferation and cell cycle alterations in oesophageal p53‐mutated cancer cells treated with cisplatin in combination with photodynamic therapy
Authors: Compagnin C. , Mognato M. , Celotti L. , Canti G. , Palumbo G. , Reddi E.
Published: April 2010

Objectives:  The major goal of anti‐cancer therapies is selective destruction of tumour cells with minimum side effects on normal cells. Towards this aim, combination of different therapeutic modalities has been evaluated for improving control of neoplastic diseases and quality of life for the patient. Photodynamic therapy (PDT) is a procedure for treatment of various types of cancer, but its combination with other established treatments has not been evaluated in detail. We have used KYSE‐510 cells from a human oesophageal carcinoma as an in vitro model to investigate whether cisplatin (CDDP) could be combined with PDT to increase cell death with respect to single treatments.

Materials and methods:  p53‐mutated KYSE‐510 cells were treated with CDDP alone or in combination with PDT. Analyses of cell viability, cell cycle progression and apoptosis induction were carried out at specific times after treatments.

Results:  Decrease in cell viability, cell cycle arrest at the G2/M‐ and S‐phases boundary, and apoptosis induction were observed after single and combined treatments.

Conclusions:  Our results show that low CDDP doses (0.25–1 μm) induce cell mortality and cell cycle perturbation, which were more evident when given in combination with PDT, but in contrast to work of other authors no synergistic activity was found. Apoptosis occurred via intrinsic pathways in treated cells, although it did not represent the predominant mode of cell death.
Isolation of therapeutically functional mouse bone marrow mesenchymal stem cells within 3 h by an effective single‐step plastic‐adherent method
Authors: Hsiao F. S.‐H. , Cheng C.‐C. , Peng S.‐Y. , Huang H.‐Y. , Lian W.‐S. , Jan M.‐L. , Fang Y.‐T. , Cheng E. C.‐H. , Lee K.‐H. , Cheng W. T.‐K. , Lin S.‐P. , Wu S.‐C.
Published: April 2010

Objectives:  Isolation of mouse mesenchymal stem cells (mMSCs), by the approach of plastic adherence, has been difficult due to persistent contamination by haematopoietic cells (HCs); we have observed that this contamination was due to engagement between HCs and mMSCs. The HCs can be lifted together with the mMSCs despite their insensitivity to trypsin digestion. Herein, we provide a single‐step procedure to rapidly segregate mMSCs from HC contaminants using transient lower‐density plastic adherence (tLDA).

Materials and methods:  The tLDA was performed by replating bone marrow adherent cells at lower density (1.25 × 104 cells/cm2) than usual, allowing for transient adherence of no more than 3 h, followed by trypsin digestion. tLDA‐isolated cells were evaluated by immunophenotyping, multi‐differentiation potentials, immunosuppressive properties, and therapeutic potential as demonstrated by symptoms of osteoporosis.

Results:  The single‐step tLDA method can effectively eliminate the persistent HC contaminants; tLDA‐isolated cells were phenotypically equivalent to those reported as mMSCs. The isolated cells possessed classic tri‐lineage differentiation potential into osteogenic, adipogenic and chondrogenic lineages and had immunosuppressive properties. After intravenous transplantation, they migrated into the allogeneic bone marrow and rescued hosts from osteoporosis symptoms, demonstrating their therapeutic potential.

Conclusions:  We have developed a simple and economical method that effectively isolates HC‐free, therapeutically functional mMSCs from bone marrow cell adherent cultures. These cells are suitable for various mechanistic and therapeutic studies in the mouse model.
Expansion of mouse sertoli cells on microcarriers
Authors: Shi B. , Zhang S. , Wang Y. , Zhuang Y. , Chu J. , Zhang S. , Shi X. , Bi J. , Guo M.
Published: April 2010

Background:  Sertoli cells (SCs) have been described as the ‘nurse cells’ of the testis whose primary function is to provide essential growth factors and create an appropriate environment for development of other cells [for example, germinal and nerve stem cells (NSCs), used here]. However, the greatest challenge at present is that it is difficult to obtain sufficient SCs of normal physiological function for cell transplantation and biological medicine, largely due to traditional static culture parameter difficult to be monitored and scaled up.

Objective:  Operational stirred culture conditions for in vitro expansion and differentiation of SCs need to be optimized for large‐scale culture.

Materials and methods:  In this study, the culturing process for primary SC expansion and maintaining lack of differentiation was optimized for the first time, by using microcarrier bead technology in spinner flask culture. Effects of various feeding/refreshing regimes, stirring speeds, seed inoculum levels of SCs, and concentrations of microcarrier used for expansion of mouse SCs were also explored. In addition, pH, osmotic pressure and metabolic variables including consumption rates of glucose, glutamine, amino acids, and formation rates of lactic acid and ammonia, were investigated in culture.

Results:  After 6 days, maximal cell densities achieved were 4.6 × 106 cells/ml for Cytodex‐1 in DMEM/FBS compared to 4.8 × 105 cells/ml in static culture. Improved expansion was achieved using an inoculum of 1 × 105 cells/ml and microcarrier concentration of 3 mg/ml at stirring speed of 30 rpm. Results indicated that medium replacement (50% changed everyday) resulted in supply of nutrients and removal of waste products inhibiting cell growth, that lead to maintenance of cultures in steady state for several days. These conditions favoured preservation of SCs in the undifferentiated state and significantly increased their physiological activity and trophic function, which were assessed by co‐culturing with NSCs and immunostaining.

Conclusion:  Data obtained in this study demonstrate the vast potential of this stirred culture system for efficient, reproducible and cost‐effective expansion of SCs in vitro. The system has advantages over static culture, which has major obstacles such as lower cell density, is time‐consuming and susceptible to contamination.
Offending behaviour in care: is children's residential care a ‘criminogenic’ environment?
Authors: Hayden Carol
Published: April 2010

This paper focuses on offending behaviour and children in residential care. The paper considers whether children's residential care is a ‘criminogenic’ environment, i.e. whether this type of care environment helps to provide the conditions that produce crime or criminality. The paper draws on the findings from recently completed research on 10 children's homes in a large county local authority in England. This paper focuses on the patterns shown in trend data collected on problematic and offending data across these homes over a 7‐year period (2001–2007) and a 1‐year cohort study of 46 young people. Interviews with care staff and young people are used to contextualize these patterns. The data provide evidence of an environment where conflict and offending behaviour are common. It is argued that the residential care environment, particularly for older teenagers, often presents a set of risks that tend to reinforce offending behaviour and that this is in part due to its ‘last resort’ status.
Expression of CCR8 is increased in asthma
Authors: Mutalithas K. , Guillen C. , Raport C. , Kolbeck R. , Soler D. , Brightling C. E. , Pavord I. D. , Wardlaw A. J.
Published: April 2010

Background
Chemokines and their receptors could play key roles in the recruitment of T cells to the asthmatic lung. CCR8 is preferentially expressed on T‐helper type 2 cells, and is thought to play a role in the pathogenesis of human asthma.

Objective
Determine the expression of CCR8 on T cells in blood, bronchoalveolar lavage (BAL) and bronchial mucosa from asthmatics and normal subjects.

Methods
CCR8 expression in blood and BAL from asthma and normal subjects was studied using flow cytometry. CCR8 expression on IFN‐γ+ and IL‐4+/IL‐13+ blood and BAL T cells was studied following stimulation with Phorbol–Myristate–Acetate and Calcium Ionophore. Paraffin‐embedded bronchial biopsies were used to study CCR8 in bronchial epithelium.

Results
The percentage of CD3+ cells expressing CCR8 in the blood was higher in asthmatics (4.7±0.4%) compared with normal subjects (3.0±0.4%; P<0.01). There was an approximately sixfold enrichment of CCR8 on IL‐4+/IL‐13+ cells compared with IFN‐γ+ T cells (P<0.001) in both asthmatic and normal subjects in both blood and BAL. Significantly more BAL T cells expressed CCR8 in asthmatic (8.6±0.8%) compared with normal subjects (3.9±0.7%) (P<0.01). In paired blood‐BAL samples from asthmatics, significantly more CCR8+CD3+ T cells were present in BAL (9.0±0.9%) than in blood (5.6±0.9%; P<0.05). There were more CCR8‐positive cells in bronchial biopsies from asthmatic (93±11 cells/mm2) compared with normal subjects (30±16 cells/mm2) (P<0.05). The ligand CCL1 was increased in the BAL of asthmatics compared with normal subjects (35±6 vs. 12.9±7 pg/mL; P<0.05).

Conclusion
There may be a role for CCR8 in the recruitment of T cells to the lung in asthmatics.

Cite this as: K. Mutalithas, C. Guillen, C. Raport, R. Kolbeck, D. Soler, C. E. Brightling, I. D. Pavord and A. J. Wardlaw, Clinical & Experimental Allergy, 2010 (40) 1175–1185.
Local administration of uridine suppresses the cardinal features of asthmatic airway inflammation
Authors: Müller T. , Grimm M. , De Vieira R. P. , Cicko S. , Dürk T. , Sorichter S. , Zissel G. , Idzko M.
Published: April 2010

Background
The immuno‐modulatory properties of nucleotides such as adenosine or inosine, have been described extensively. Recently, the nucleoside uridine and its analogue 4‐thiouridine have gained attention for their protective role in acute lung inflammation.

Objective
In this study, we investigated the influence of uridine on asthmatic airway inflammation.

Methods
We used the classical ovalbumin (OVA)–alum model, as well as a model of house dust mite‐(HDM)‐induced airway inflammation. The degree of inflammation was determined by bronchoalveolar lavage (BAL), histology, and measurement of bronchial hyperresponsiveness.

Results
Intratracheal treatment of OVA‐sensitized animals with uridine before allergen challenge resulted in a reduction in total BAL cells and BAL eosinophils. This was accompanied by reduced tissue infiltration and diminished production of T helper type 2‐cytokines by mediastinal lymph node cells. Additionally, mice treated with uridine developed less bronchial hyperresponsiveness. Uridine was also effective in reducing airway inflammation in HDM‐induced asthma. The protective effects of uridine were independent of myeloid dendritic cell (mDC) function, because in vitro pre‐treatment of allergen‐pulsed DCs with uridine did not alter the degree of inflammation. However, uridine inhibited the release of pro‐inflammatory mediators in vivo and by cultured lung epithelial cells, suggesting an effect on lung structural cells.

Conclusion
In summary, we were able to show that uridine inhibits the classical features of asthmatic airway inflammation. As uridine supplementation is well tolerated in humans, it might be a new therapeutic approach for the treatment of bronchial asthma.

Cite this as: T. Müller, M. Grimm, R. P. de Vieira, S. Cicko, T. Dürk, S. Sorichter, G. Zissel and M. Idzko, Clinical & Experimental Allergy, 2010 (40) 1552–1560.