bluuebunny/crossref_metadata_2025 huggingface dataset:
Convergence zones and their impact on the initiation of a mesoscale convective system in West Africa
Authors: Klüpfel Vera , Kalthoff Norbert , Gantner Leonhard , Taylor Christopher M.
Published: November 2011

During the African Monsoon Multidisciplinary Analysis (AMMA) campaign in 2006, extended surface and boundary‐layer measurements were performed to study the influence of soil‐moisture patterns on the generation of thermally forced circulations and triggering of deep convection. However, not all processes involved in the triggering of a mesoscale convective system (MCS) could be identified in previous studies. Therefore, COSMO (Consortium for Small‐scale Modeling) simulations were carried out investigating possible trigger mechanisms. On 31 July 2006, an MCS was initiated and on 1 August, soil‐moisture inhomogeneities resulted in a thermally forced circulation with an associated convergence zone, but no deep convection was triggered. It was found that the MCS on 31 July was influenced by a cyclonic vortex and favoured by the superposition of two convergence zones of different origins. Initiation of the MCS occurred in the simulation when moist monsoon air was transported to the north, associated with a cold pool ahead of another MCS, and reached the convergence zone. On 1 August, the simulation reproduced the thermally forced circulation caused by the soil‐moisture pattern, which had been produced by the precipitation of the MCS. However, due to low humidity in the boundary layer and low convective available potential energy, the lifting along the convergence zone did not trigger deep convection. Copyright © 2011 Royal Meteorological Society
Pregnancy loss after chorionic villus sampling and genetic amniocentesis in twin pregnancies: a systematic review
Authors: Agarwal K. , Alfirevic Z.
Published: November 2011

Objective

To review the available evidence regarding pregnancy loss following first‐trimester chorionic villus sampling (CVS) and mid‐trimester genetic amniocentesis in twins.

Methods

We searched the MEDLINE database from January 1990 to May 2011 for randomized and cohort studies reporting on the risk of pregnancy loss after first‐trimester CVS performed between 9 and 14 weeks and after genetic amniocentesis performed between 14 and 22 weeks. Where appropriate, we calculated pooled proportions and relative risks with 95% CI.

Results

No randomized studies were found. For CVS, nine studies fulfilled the inclusion criteria. The overall pregnancy‐loss rate was 3.84% (95% CI, 2.48–5.47; n = 4). The rate of pregnancy loss before 20 weeks was 2.75% (95% CI, 1.28–4.75; n = 3) and before 28 weeks was 3.44% (95% CI, 1.67–5.81; n = 3). For amniocentesis, the overall pregnancy‐loss rate was 3.07% (95% CI, 1.83–4.61; n = 4). The rate of pregnancy loss before 20 weeks was 2.25% (95% CI, 1.23–3.57; n = 2), before 24 weeks was 2.54% (95% CI, 1.43–3.96; n = 9) and before 28 weeks was 1.70% (95% CI, 0.37–3.97; n = 5). Pooled data from four case–control studies showed a higher risk (2.59% vs. 1.53%) of pregnancy loss before 24 weeks following amniocentesis (relative risk = 1.81; 95% CI, 1.02–3.19). There were no statistically significant differences in reported pregnancy loss between transabdominal and transcervical approaches, use of a single‐needle system vs. a double‐needle system and single uterine entry vs. double uterine entry in the CVS group. Similarly, in the amniocentesis group, there was no statistically significant difference in fetal loss between the single uterine entry vs. the double uterine entry.

Conclusion

In the absence of randomized studies, it is not possible to estimate accurately the excess risk following invasive procedures in twins. Currently available data show similar overall pregnancy‐loss rates for both amniocentesis and CVS with the excess risk of around 1% above the background risk. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Incontinence after primary repair of obstetric anal sphincter tears is related to relative length of reconstructed external sphincter: a case–control study
Authors: Norderval S. , Røssaak K. , Markskog A. , Vonen B.
Published: November 2011

Objective

To determine if anatomic primary repair with end‐to‐end reconstruction of the external anal sphincter (EAS) in its full length combined with separate repair of coexisting internal anal sphincter (IAS) tear, when present, results in less incontinence and better anal sphincter integrity compared with conventional primary end‐to‐end repair in which the IAS is not actively reconstructed.

Methods

Women who sustained third‐ or fourth‐degree obstetric tears were included prospectively in the study following anatomic primary repair. Women treated with conventional primary repair prior to the study period comprised the control group. Three‐dimensional endoanal ultrasonography (3D‐EAUS) images were classified according to the EAUS defect score, and incontinence according to St Mark's score.

Results

Sixty‐three women were included in the study group and 61 in the control group, with mean follow‐up times of 11 and 21 months, respectively. Among women who had not delivered vaginally prior to the tear, St Mark's score ≥ 3 was reported by 9.6% (5/52) in the study group and 37.5% (15/40) in the control group at follow‐up (P = 0.002). The corresponding numbers among women who had previously delivered vaginally were 36.4% (4/11) and 42.9% (9/21), respectively (non‐significant). St Mark's score correlated with the EAUS defect score (P = 0.017). An EAS defect exceeding 50% of the sphincter length was significantly less common in the study group, and in a multivariable logistic regression model, mode of repair (anatomic vs conventional) was the only factor explaining the difference in EAS sphincter length between the two groups (P = 0.007).

Conclusion

Improved continence status after anatomic primary repair was associated with a better longitudinal reconstruction of the EAS, while the integrity of the IAS did not differ between the groups. Women with a history of vaginal delivery prior to the sphincter tear had an inferior outcome regardless of mode of repair. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
A middleware for assured clouds
Authors: Campbell Roy H. , Montanari Mirko , Farivar Reza
Published: November 2011

This paper considers mission assurance for critical cloud applications, a set of applications with growing importance to governments and military organizations. Specifically, we consider applications in which assigned tasks or duties are performed in accordance with an intended purpose or plan in order to accomplish an assured mission. Mission-critical cloud computing may possibly involve hybrid (public, private, heterogeneous) clouds and require the realization of “end-to-end” and “cross-layered” security, dependability, and timeliness. We propose the properties and building blocks of a middleware for assured cloud computing that can support critical missions. In this approach, we assume that mission critical cloud computing must be designed with assurance in mind. In particular, the middleware in such systems must include sophisticated monitoring, assessment of policies, and response to manage the configuration and management of dynamic systems-of-systems with both trusted and partially trusted resources (data, sensors, networks, computers, etc.) and services sourced from multiple organizations.
Bringing light to the inner life of synapses
Authors: Sigrist S.J. , Wichmann C.
Published: November 2011

Chemical synapses are pivotal for information transfer and storage within neuronal circuit­y. At the same time, various diseases of the nervous system most likely originate from disturbances in synapse structure and function. Synapses are very fast, extremely con­trolled and effective communication devices, with synaptic vesicles fusing at specialized membrane domains associated with highly-ordered protein architectures (cytomatrices) traditionally seen using electron microsco­py. Drosophila synapses with prominent cytomatrices called T-bars provide per se a highly suitable model system to apply genetic analysis to the roles of these protein architectures. Here we describe the principles behind these techniques as well as their application to the analysis of the molecular architecture of the synapse. In this context, the advent of super-resolution light microscopy methods yielding two- to 10-fold higher resolution than conventional microscopy has provided an efficient tool.
Effects of body elasticity on stability of underwater locomotion
Authors: Jing F. , Kanso E.
Published: November 2011

We examine the stability of the ‘coast’ motion of fish, that is to say, the motion of a neutrally buoyant fish at constant speed in a straight line. The forces and moments acting on the fish body are thus perfectly balanced. The fish motion is said to be unstable if a perturbation in the conditions surrounding the fish results in forces and moments that tend to increase the perturbation, and it is stable if these emerging forces tend to reduce the perturbation and return the fish to its original state. Stability may be achieved actively or passively. Active stabilization requires neurological control that activates musculo-skeletal components to compensate for the external perturbations acting against stability. Passive stabilization on the other hand requires no energy input by the fish and is dependent upon the fish morphology, i.e. geometry and elastic properties. In this paper, we use a deformable body consisting of an articulated body equipped with torsional springs at its hinge joints and submerged in an unbounded perfect fluid as a simple model to study passive stability as a function of the body geometry and spring stiffness. We show that for given body dimensions, the spring elasticity, when properly chosen, leads to passive stabilization of the (otherwise unstable) coast motion.
Cardiorespiratory fitness and dietary intake in European adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence study
Authors: Cuenca-García M. , Ortega F. B. , Huybrechts I. , Ruiz J. R. , González-Gross M. , Ottevaere C. , Sjöström M. , Dìaz L. E. , Ciarapica D. , Molnar D. , Gottrand F. , Plada M. , Manios Y. , Moreno L. A. , De Henauw S. , Kersting M. , Castillo M. J.
Published: November 2011

The present study investigated the association between cardiorespiratory fitness (CRF) and dietary intake in European adolescents. The study comprised 1492 adolescents (770 females) from eight European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. CRF was assessed by the 20 m shuttle run test. Adolescents were grouped into low and high CRF levels according to the FITNESSGRAM Standards. Dietary intake was self-registered by the adolescents using a computer-based tool for 24 h dietary recalls (HELENA-Dietary Assessment Tool) on two non-consecutive days. Weight and height were measured, and BMI was calculated. Higher CRF was associated with higher total energy intake in boys (P = 0·003). No association was found between CRF and macronutrient intake (as percentage of energy), yet some positive associations were found with daily intake of bread/cereals in boys and dairy products in both boys and girls (allP < 0·003), regardless of centre, age and BMI. CRF was inversely related to sweetened beverage consumption in girls. These findings were overall consistent when CRF was analysed according to the FITNESSGRAM categories (high/low CRF). A high CRF was not related to compliance with dietary recommendations, except for sweetened beverages in girls (P = 0·002). In conclusion, a high CRF is associated with a higher intake of dairy products and bread/cereals, and a lower consumption of sweetened beverages, regardless of centre, age and BMI. The present findings contribute to the understanding of the relationships between dietary factors and physiological health indicators such as CRF.
Effects of fusicoccin and gibberellic acid on the germination of embryos from dormant barley grains: roles of starch degradation and external pH
Authors: van der Meulen René M. , Lamers Gerda E.M. , Caspers Martien P.M. , Heistek Jolanda C. , de Boer Albertus H. , van Duijn Bert , Wang Mei
Published: November 2011

Abstract In isolated embryos from dormant barley grains, synergistic effects of fusicoccin (FC) and gibberellic acid (GA3) were observed on the induction of α-amylase mRNA expression. However, no α-amylase mRNA expression could be induced by both agents in embryos from non-dormant grains. Both light- and electron-microscopy studies demonstrated that there were large numbers of starch granules present in mature embryos (mainly in scutellum) from dormant barley grains but none or almost none in embryos from non-dormant grains. Furthermore, the content of reducing sugars in embryos from dormant grains was about half of that from non-dormant grains. In contrast to GA3, FC was able to induce a strong acidification of extracellular pH (pHe). Clamping the pHeto prevent FC-induced acidification, by using 50 mM MES buffer (pH 5.6), caused an inhibition of GA3- or FC-induced α-amylase mRNA expression but did not affect the germination of embryos from dormant grains. In addition, in MES buffer, addition of FC or a combination of FC and GA3increased the germination rate of embryos isolated from dormant grains, though large numbers of starch granules were still present in these embryos. Based on these observations, the presence of starch granules and a low reducing sugar level in embryos from dormant grains is not a factor for control of grain dormancy and germination.
Geophysical and geochemical survey of a large marine pockmark on the Malin Shelf, Ireland
Authors: Szpak M. T. , Monteys X. , O'Reilly S. , Simpson A. J. , Garcia X. , Evans R. L. , Allen C. C. R. , McNally D. J. , Courtier‐Murias D. , Kelleher B. P.
Published: November 2011

Marine pockmarks are a specific type of seabed geological setting resembling craters or pits and are considered seabed surface expressions of fluid flow in the subsurface. A large composite pockmark on the Malin Shelf, off the northern coast of Ireland was surveyed and ground truthed to assess its activity and investigate fluid related processes in the subsurface. Geophysical (including acoustic and electromagnetic) data confirmed the subsurface presence of signatures typical of fluids within the sediment. Shallow seismic profiling revealed a large shallow gas pocket and typical gas related indicators such as acoustic blanking and enhanced reflectors present underneath and around the large pockmark. Sulphate profiles indicate that gas from the shallow reservoir has been migrating upwards, at least recently. However, there are no chimney structures observed in the sub‐bottom data and the migration pathways are not apparent. Electromagnetic data show slightly elevated electrical conductivity on the edges of the pockmarks and a drop below regional levels within the confines of the pockmark, suggesting changes in physical properties of the sediment. Nuclear Magnetic Resonance (NMR) experiments were employed to characterize the organic component of sediments from selected depths. Very strong microbial signatures were evident in all NMR spectra but microbes outside the pockmark appear to be much more active than inside. These observations coincide with spikes in conductivity and the lateral gas bearing body suggesting that there is an increase in microbial activity and biomass when gas is present.
Conditions of Mytilus edulis extracellular body fluids and shell composition in a pH‐treatment experiment: Acid‐base status, trace elements and δ11B
Authors: Heinemann Agnes , Fietzke Jan , Melzner Frank , Böhm Florian , Thomsen Jörn , Garbe‐Schönberg Dieter , Eisenhauer Anton
Published: November 2011

Mytilus edulis were cultured for 3 months under six different seawater pCO2 levels ranging from 380 to 4000 μatm. Specimen were taken from Kiel Fjord (Western Baltic Sea, Germany) which is a habitat with high and variable seawater pCO2 and related shifts in carbonate system speciation (e.g., low pH and low CaCO3 saturation state). Hemolymph (HL) and extrapallial fluid (EPF) samples were analyzed for pH and total dissolved inorganic carbon (CT) to calculate pCO2 and [HCO3−]. A second experiment was conducted for 2 months with three different pCO2 levels (380, 1400 and 4000 μatm). Boron isotopes (δ11B) were investigated by LA‐MC‐ICP‐MS (Laser Ablation–Multicollector–Inductively Coupled Plasma–Mass Spectrometry) in shell portions precipitated during experimental treatment time. Additionally, elemental ratios (B/Ca, Mg/Ca and Sr/Ca) in the EPF of specimen from the second experiment were measured via ICP‐OES (Inductively Coupled Plasma–Optical Emission Spectrometry). Extracellular pH was not significantly different in HL and EPF but systematically lower than ambient water pH. This is due to high extracellular pCO2 values, a prerequisite for metabolic CO2 excretion. No accumulation of extracellular [HCO3−] was measured. Elemental ratios (B/Ca, Mg/Ca and Sr/Ca) in the EPF increased slightly with pH which is in accordance with increasing growth and calcification rates at higher seawater pH values. Boron isotope ratios were highly variable between different individuals but also within single shells. This corresponds to a high individual variability in fluid B/Ca ratios and may be due to high boron concentrations in the organic parts of the shell. The mean δ11B value shows no trend with pH but appears to represent internal pH (EPF) rather than ambient water pH.
The role of the overriding plate thermal state on slab dip variability and on the occurrence of flat subduction
Authors: Rodríguez‐González Juan , Negredo Ana M. , Billen Magali I.
Published: November 2011

Slab dip varies significantly, both between different, and along single subduction zones. Provided that old subducting plates are colder and denser than young plates, variations in the slab dip should correlate with slab age. However, recent statistical analyses do not show this expected correlation. We present the results of non‐Newtonian numerical dynamic models where subduction is driven by means of a kinematic boundary condition. We systematically vary the age of both the overriding and subducting plates in order to test these effects on the slab dip at different depth ranges. We find that colder overriding plates result in shallower slab dips and episodes of flat slab subduction, as a result of the increased suction force in the mantle wedge. The influence of the thermal state of the overriding plate on slab dip is shown here to be more important than that of the age of subducting lithosphere. Modeling results are qualitatively compared to the large dip variability of the Cocos slab including a flat‐slab segment. We suggest that this variability is likely related to the change of the thermal state of the overriding plates, with flat subduction occurring under cold lithosphere in southwestern Mexico and steep subduction under the warmer lithosphere of the northwestern Caribbean plate.
Temporal Processing Deficits in Hebrew Speaking Children With Reading Disabilities
Authors: Mimran Ravit Cohen-
Published: November 2011

The purpose of this study was to assess to what extent specific reading disabilities and poor phonologic processing in children who read Hebrew, a primarily consonant orthography, are related to central auditory temporal processing deficits (TPDs).

Twenty-four Hebrew-speaking children (ages 10–13) with and without reading disabilities were asked to discriminate auditorily pairs of syllables (/ba/ vs. /pa/) that differ by voice onset time (VOT) only. Two paradigms were used, 1 with a short interstimulus interval (ISI) (50 ms) and 1 with a long ISI (500 ms). Event-related potentials (ERPs) were measured in response to the two syllables in an auditory oddball task.

Results showed significantly lowered accuracy, longer reaction times, and prolonged P3 latency among the group with reading disabilities compared with the control group. No significant differences were found between the short ISI task and the long ISI task. However, significant correlations were found between the phonologic processing tasks and the short ISI task.

These findings in the Hebrew language are consistent with findings from other languages and add support to the central TPD hypothesis of reading disabilities. The discussion highlights how investigating different orthographic systems can deepen our understanding of the role TPD plays in reading.
Training Synaesthesia
Authors: Rothen Nicolas , Wantz Andrea-Laura , Meier Beat
Published: November 2011

Synaesthetic inducers such as graphemes are typically cultural artifacts. Thus, a learning component seems evident in synaesthesia (Simner et al, 2009 Brain132 57 – 64). Normally, synaesthetes report to have their experiences since they can remember. Nevertheless, a recent training study suggests that synaesthesia can be mimicked in non-synaesthetes. To date, the role of learning during the development of synaesthesia is still debated. It is not clear whether synaesthesia can be learned or trained at all. To address this question, we compared a non-adaptive and an adaptive training for their effectiveness. We assessed their impact on two types of priming tasks, before and after the training. We found stronger priming in the adaptive training group suggesting that adaptive training is more efficient to mimic synaesthesia.
Divergent Synthesis of Benzo[d]thiazoles by PIFA-Mediated Cyclization of β-Oxo Thioamides
Authors: Huang Peng , Fu Xiaolan , Liang Yongjiu , Zhang Rui , Dong Dewen
Published: November 2011

Efficient and divergent synthesis of benzo[d]thiazoles is developed from readily available β-oxo thioamides mediated by hypervalent iodine reagent phenyliodine bis(trifluoroaceate) (PIFA) based on reaction conditions selection, which involves the formation of a radical cation and its subsequent intramolecular cyclization process.
How far can diachronic change be predicted
Authors: Spina Rosella , Dressler Wolfgang U.
Published: November 2011

This paper attempts to predict diachronic change in the restricted domain of Italo-Romance first person plural present indicative allomorphs, starting from the reconstructed Proto-Italo-Romance forms -amo, -emo, -imo, preserved in several dialects to this day (with corresponding subjunctives -emo, -iamo, -iamo). The predictions, or rather retrodictions (to be differentiated below) are based on the theory of Natural Morphology (NM). Morphology-initiated changes lead to 64 logically conceivable distributions in the earlier and present Italo-Romance dialects. The retrodictions are meant to account for the identity of attested distributions with possible (‘legal’) distributions, for unattested impossible (‘illegal’) distributions and for two accidental gaps in distributions. Moreover, we try to predict why certain attested distributions are more probable and therefore more frequent than others and introduce a new method of empirically testing such probability retrodictions.
The Tonic Chord and Lacan's Object a in Selected Songs by Charles Ives
Authors: Smith Kenneth M.
Published: November 2011

ABSTRACT

A musical response to Lacan's concept of the objet petit a – the imaginary ‘object-cause’ of desire – accounts for certain songs by Charles Ives in which ‘tonic’ chords are signified by complex networks of dominant-seventh harmonies. These objects of tonal desire adopt the structure of both lack (as absent centre) and surplus (as multiple tonal centres). In each song, Ives employs individual harmonic techniques to question the ability of tonic chords to coordinate a fractured tonality. Investigating Afterglow, Serenity, At Sea and Mists from the 1922 collection of 114 Songs, I explore the Lacanian dimensions of each text and setting, bringing out the message that each song offers about the function of the tonic. An analysis of Premonitions exemplifies a distinction Slavoj Žižek proposed between a functional system in which the object a coordinates desire as absent centre, and a system in which the object is stripped of its organizational power.
Casein kinase I delta controls centrosome positioning during T cell activation
Authors: Zyss Deborah , Ebrahimi Hani , Gergely Fanni
Published: November 2011

Although termed central body, the centrosome is located off-center in many polarized cells. T cell receptor (TCR) engagement by antigens induces a polarity switch in T cells. This leads to the recruitment of the centrosome to the immunological synapse (IS), a specialized cell–cell junction. Despite much recent progress, how TCR signaling triggers centrosome repositioning remains poorly understood. In this paper, we uncover a critical requirement for the centrosomal casein kinase I delta (CKIδ) in centrosome translocation to the IS. CKIδ binds and phosphorylates the microtubule plus-end–binding protein EB1. Moreover, a putative EB1-binding motif at the C terminus of CKIδ is required for centrosome translocation to the IS. We find that depletion of CKIδ in T lymphocytes and inhibition of CKI in epithelial cells reduce microtubule growth. Therefore, we propose that CKIδ–EB1 complexes contribute to the increase in microtubule growth speeds observed in polarized T cells, a mechanism that might serve to generate long-stable microtubules necessary for centrosome translocation.
Succession‐induced trait shifts across a wide range of NW European ecosystems are driven by light and modulated by initial abiotic conditions
Authors: Douma Jacob C. , de Haan Martin W. A. , Aerts Rien , Witte Jan‐Philip M. , van Bodegom Peter M.
Published: November 2011

1. For truly predictive community ecology, it is essential to understand the interplay between species traits, their environment and their impacts on the composition of plant communities. These interactions are increasingly understood for various environmental drivers, but our understanding of how traits, in general, change during succession is still modest. We hypothesize that (initial) abiotic conditions other than light drive the successional dynamics of other traits. The idea that different initial abiotic conditions lead to different trait trajectories during succession was predicted long ago but has never been tested for traits.

2. In this study, we compared the successional (decades to centuries) trait trajectories of 19 ecosystem types in low‐altitude NW Europe using a database including >4700 plots. We tested which traits (out of a total of 12, including those associated with light competition strategies) show consistent shifts across ecosystems. Additionally, we investigated, through a novel partitioning of trait differences (using partial principal component analyses), whether abiotic factors can explain trait shifts that occur over and above light‐induced trait shifts.

3. We show that canopy height, woodiness, leaf size and seed mass increase, and flowering onset and flowering duration decrease consistently with succession across ecosystems, while leaf economic traits and life span showed a mixed response during succession. Accounting for the effect of height revealed that the initial and prevailing abiotic conditions – particularly soil moisture – co‐determine trait shifts during succession. Therefore, different initial starting conditions may lead to different trajectories in trait space, most notably due to the differential response of specific leaf area (SLA), leaf nitrogen content and life span. For example, SLA decreases in seres that become drier over time (initially very wet), while it increases in seres that become wetter over time (initially very dry).

4. Synthesis. Our novel approach of partitioning successional trait shifts between the influence of competition for light and other abiotic factors showed that trajectories of ecosystems through trait space can be explained by a combination of the two: a universal response to changing light availability and a specific response depending on initial abiotic conditions.
Oral and intravenous l‐[1‐13C]phenylalanine delivery measure similar rates of elimination when gastric emptying and splanchnic extraction are accounted for in adult mixed hounds1–4
Authors: Gooding M. A. , Cant J. P. , Pencharz P. B. , Davenport G. M. , Atkinson J. L. , Shoveller A. K.
Published: November 2011

There are few reported estimates of amino acid (AA) kinetics in adult mammals and none exist in adult dogs. The study objectives were to evaluate the use of oral isotope delivery in contrast to the more commonly used intravenous (IV) delivery to estimate AA kinetics in adult dogs and to estimate splanchnic extraction and gastric emptying using a commonly accepted mathematical model. Dogs received 25 × 1/2‐hourly meals (13 g/kg BW/day) and either an oral or IV bolus of l‐[1‐13C]Phe (12 mg/kg BW). Blood samples were taken immediately before each feeding. Concentrations of plasma Phe were measured using liquid chromatography‐tandem mass spectrometry. There were no differences in baseline plasma Phe concentrations (34 μm ± 0.61), Phe distribution volume, Phe pool size and rate constants between dogs when the tracer was administered IV or orally (p > 0.25). Decay curve for plasma l‐[1‐13C]Phe differed between IV and oral dosing protocols with IV dosing fit best using a two‐compartment model. Phe disappeared from plasma at a mean rate of 2.8%/min. Estimates of gastric emptying and splanchnic extraction did not differ based on oral or IV tracer dosing when the decay curves were fit with the two‐compartment model (p > 0.40). The half‐life for gastric emptying was 18 min, and first‐pass Phe extraction by the splanchnic bed was 24% of the dietary Phe. These results suggest that oral isotope dosing can be used as an alternative to IV isotope dosing in studies that utilize a primed, constant dosing approach to measure protein and amino acid kinetics.
New Insights in the Life Cycle and Epidemics of Phytophthora porri on Leek
Authors: Declercq Bart , Devlamynck Jasper , De Vleesschauwer David , Cap Nathalie , De Nies Joris , Pollet Sabien , Höfte Monica
Published: November 2011

White tip, caused by Phytophthora porri, is a devastating disease in the autumn and winter production of leek (Allium porrum) in Europe. This study investigated the disease cycle of P. porri in laboratory and field conditions. Oospores readily germinated in the presence of non‐sterile soil extract at any temperature between 4 and 22°C, with the formation of sporangia which released zoospores. The zoospores survived at least 7 weeks in water at a temperature range of 0 till 24°C. Microscopic examinations revealed that zoospores encysted and germinated on the leek leaf surface and hyphae entered the leaf directly through stomata or by penetrating via appressoria. Oospores were formed in the leaves within 6 days, while sporangia were not produced. By monitoring disease progress in fields with a different cropping history of leek, it could be deduced that P. porri survives in soil for up to 4 years. Disease progress during three consecutive years was correlated with average daily rainfall in the infection period. Disease incidence on leek was reduced when rain splash was excluded by growing the plants in an open hoop greenhouse. Based on these findings, we propose a disease cycle for P. porri in which oospores germinate in puddles, and zoospores reach the leaves by rain splash and survive in water in the leaf axils, from where they infect the plant by direct penetration or via stomata. When conditions become unfavourable, oospores are produced in the leaves which again reach the soil when leaves decay. Secondary spread of the disease by sporangia does not seem to be important.
Long‐term oral intake of aluminium or zinc does not accelerate Alzheimer pathology in AβPP and AβPP/tau transgenic mice
Authors: Akiyama Haruhiko , Hosokawa Masato , Kametani Fuyuki , Kondo Hiromi , Chiba Momoko , Fukushima Masako , Tabira Takeshi
Published: November 2011

Whether or not the oral intake of metals such as aluminium (Al) and zinc (Zn) is a risk for Alzheimer's disease (AD) has been a matter of controversy. Lack of AD pathology in patients with Al encephalopathy indicates Al does not cause AD. On the other hand, some epidemiological studies have suggested high Al increases the occurrence of AD. Our purpose is to test if high Al in drinking water is a risk factor for AD. We administered Al and Zn in drinking water to Tg2576, a transgenic mouse model for amyloid β‐protein (Aβ) deposition with the Aβ precursor protein (AβPP) mutations (K670N/M671L), and Tg2576/tau(P301L), a model for Aβ and tau deposition. Deionized water was given to the control Tg2576 and Tg2576/tau. After administration for 4–10 months of approximately 100 mg/kg body weight Al or Zn per day, we were not able to find by quantitative immunohistochemical analyses differences in the deposition of Aβ and tau between the treated and untreated groups. Nor did the Al or Zn treatment affect the amount of soluble Aβ and Aβ*56, an Aβ oligomer, measured by ELISA or immunoblot. The oral intake of excess Al or Zn does not accelerate AD pathology in the transgenic mouse models for Aβ and tau accumulation. Such results do not seem to support the notion that excessive oral intake of Al or Zn is a risk factor for AD.
Human norovirus occurrence and diversity in the Llobregat river catchment, Spain
Authors: Pérez‐Sautu Unai , Sano Daisuke , Guix Susana , Kasimir Georg , Pintó Rosa M. , Bosch Albert
Published: November 2011

Human noroviruses (NoV) were quantified and characterized in an 18 month survey conducted along the Llobregat river catchment in Spain. Sample types included freshwater, untreated and treated wastewater and drinking water. High NoV genome copy numbers were reported, reaching up to 106 l−1 and 109 l−1 in freshwater and raw sewage respectively. In both types of samples, GII NoV genome copies outnumbered those of GI, although without significance. All samples of semi‐treated and treated drinking water were negative for NoV. A clear seasonality of NoV occurrence was observed both in river water and sewage samples, with significantly higher genome copy numbers in the cold than in the warm months period. Mean NoV log reduction rates after biological treatment of sewage were 2.2 and 3.1 for GI and GII respectively. A total of 77 NoV strains isolated in the Llobregat river catchment could be phylogenetically characterized, 44 belonging to GI and 33 to GII. The most prevalent genotype was GI.4, followed by GII.4 and GII.21. Several variants of the pandemic GII.4 strain were detected in the environment, corroborating their circulation among the population.
Acquisition of iron by Trichodesmium and associated bacteria in culture
Authors: Roe Kelly L. , Barbeau Katherine , Mann Elizabeth L. , Haygood Margo G.
Published: November 2011

Trichodesmium colonies contain an abundant microbial consortium that is likely to play a role in nutrient cycling within the colony. This study used laboratory cultures of Trichodesmium and two genome‐sequenced strains of bacteria typical of Trichodesmium‐associated microbes to develop an understanding of the cycling of iron, a potentially limiting micronutrient, within Trichodesmium colonies. We found that the ferric siderophores desferrioxamine B and aerobactin were not readily bioavailable to Trichodesmium, relative to ferric chloride or citrate‐associated iron. In contrast, the representative bacterial strains we studied were able to acquire iron from all of the iron sources, implying that naturally occurring Trichodesmium‐associated bacteria may be capable of utilizing a more diverse array of iron sources than Trichodesmium. From the organism‐specific uptake data collected in this study, a theoretical Trichodesmium colony was designed to model whole colony iron uptake. The bacteria accounted for most (> 70%) of the iron acquired by the colony, highlighting the importance of determining organism‐specific uptake in a complex environment. Our findings suggest that, although they may share the same micro‐environment, Trichodesmium and its colony‐associated microbial cohort may differ substantially in terms of iron acquisition strategy.
The anal fistula claw: the OTSC clip for anal fistula closure
Authors: Prosst R. L. , Herold A. , Joos A. K. , Bussen D. , Wehrmann M. , Gottwald T. , Schurr M. O.
Published: November 2011

Aim  Surgical closure of high or complex anal fistulae is often a difficult challenge. A special Nitinol clip, the OTSC clip (Ovesco AG), was evaluated for fistula closure in a porcine model.

Method  A total of 20 fistulae were created in 10 animals by seton insertion. Four weeks after fistula induction the setons were removed: one internal fistula opening per animal was left untreated as control whereas the other opening was closed by the OTSC clip using a specially developed transanal clip applicator. The safety and technical feasibility of the clip application were tested. Another 4 weeks later, fistulae were macroscopically assessed for closure. For histological examination, the anorectum including the fistula tract was excised en bloc.

Results  Four weeks after clip placement, all external and internal fistula openings were macroscopically closed. The clip application site presented with an increased scarring. Microscopically, 40% of residual tracts and a more intense chronic inflammation were seen in the untreated control fistulae. After clip placement, 10% of the fistulae persisted associated with a higher density of collagen fibres indicating a better fistula scarring and healing. No unexpected side‐effects or complications caused by the clip were observed.

Conclusion  Fistula closure using the OTSC clip represents a promising sphincter‐preserving minimally invasive procedure. This study demonstrated the safety and feasibility of the ‘anal fistula claw’ for fistula closure. In spite of limitations of the porcine model the results justify clinical applications and further investigations.
Risk, protection, and resilience in Chinese adolescents: A psycho‐social study
Authors: Li Haibin , Martin Andrew J. , Armstrong Derrick , Walker Richard
Published: November 2011

A total of 636 Grade 11 Chinese students completed measures of risk factors, protective factors, and problem behaviour complemented by achievement data. In terms of risk factors, poor parental management and low school commitment were significant predictors of problem behaviour while low school commitment was a significant predictor of low academic achievement. In terms of protective factors, family attachment, opportunities and recognition for pro‐social involvement in school, and high school expectation of behaviour negatively predict problem behaviour. Pro‐social involvement in school and high expectations of behaviour significantly predict academic achievement. There was also a significant difference on protective factors between resilient and non‐resilient groups from high‐risk family environments.
Family Status and Work Attitudes: An Investigation in a Professional Services Firm
Authors: de Janasz Suzanne , Forret Monica , Haack Debra , Jonsen Karsten
Published: November 2011

To help employees better balance work and family responsibilities, organizations are increasingly offering a variety of work–family programmes. However, anecdotal reports suggest that employees without spouses or children perceive that they receive fewer organizational benefits and bear greater burdens than their married or parent counterparts. By providing a more ‘family‐friendly’ work environment, organizations may foster perceptions of inequity in people without families (single adults without dependent children, SAWDCs), possibly resulting in lower job satisfaction and other work‐related outcomes. Using a sample of 454 employees of a professional services firm, we examined attitudinal differences between individuals with and without families. Findings suggest that SAWDCs and non‐SAWDCS differed in terms of age, organizational level, use of flexible work arrangements and firm tenure. However, we found no differences in hours worked, job involvement, job satisfaction or organizational commitment. Interestingly, SAWDCs had more favourable perceptions of the organization's work–family culture than non‐SAWDCs, suggesting that those who do not utilize family‐friendly benefits view them more favourably than those who actually need or use the benefits. In addition to identifying directions for future research, we offer suggestions for organizations, including taking a more universal approach to benefits to the advantage of all employees.
Research Review: Altered reward function in adolescent depression: what, when and how?
Authors: Forbes Erika E. , Dahl Ronald E.
Published: November 2011

Background:  Conceptual models and recent evidence indicate that neural response to reward is altered in depression. Taking a developmental approach to investigating reward function in adolescent depression can elucidate the etiology, pathophysiology and course of depression, a disorder that typically begins during adolescence and has high rates of recurrence.

Methods:  This conceptual review describes the what, when and how of altered reward function in adolescent depression. With the goal of generating new, testable hypotheses within a developmental affective neuroscience framework, we critically review findings and suggest future directions. Peer‐reviewed empirical papers for inclusion in this critical review were obtained by searching PubMed, PsycInfo and ScienceDirect for the years 1990–2010.

Results:  A pattern of low striatal response and high medial prefrontal response to reward is evident in adolescents and adults with depression. Given the salience of social stimuli for positive affect and depression, reward function might be especially disrupted in response to social rewards. Because of changes in the dopamine system and reward function with aging, altered reward function in depression might be more evident during adolescence than later in life; however, low reward function may also be a stable characteristic of people who experience depression. Mechanisms of altered reward function in depression could include disrupted balance of corticostriatal circuit function, with disruption occurring as aberrant adolescent brain development.

Conclusions:  Future studies should examine responses to social rewards; employ longitudinal and prospective designs; and investigate patterns of functional connectivity in reward circuits. Understanding altered reward function in depression has potential implications for treatment development. A more rigorous approach to investigating anhedonia, threat–reward interactions and comorbid anxiety will be valuable to future progress in describing the role of reward function in the pathophysiology of depression.
The physiology of the β‐amyloid precursor protein intracellular domain AICD
Authors: Pardossi‐Piquard Raphaëlle , Checler Frédéric
Published: November 2011

J. Neurochem. (2012) 120 (Suppl. 1), 109–124.

The amyloid‐β precursor protein (βAPP) undergoes several cleavages by enzymatic activities called secretases. Numerous studies aimed at studying the biogenesis and catabolic fate of Aβ peptides, the proteinaceous component of the senile plaques that accumulate in Alzheimer’s disease‐affected brains. Relatively recently, another secretase‐mediated β‐APP‐derived catabolite called APP IntraCellular Domain (AICD) entered the game. Whether AICD corresponded to a biologically inert by‐pass product of βAPP processing or whether it could harbor its own function remained questionable. In this study, we review the mechanisms by which AICD is generated and how its production is regulated. Furthermore, we discuss the degradation mechanism underlying its rapid catabolic fate. Finally, we review putative AICD‐related functions and more particularly, the numerous studies indicating that AICD could translocate to the nucleus and control at a transcriptional level, the expression of a series of proteins involved in various functions including the control of cell death and Aβ degradation.
Computer‐based evaluation of methods to sample nitrate leached from grazed pasture
Authors: Lilburne L. , Carrick S. , Webb T. , Moir J.
Published: November 2011

Scientists, land managers and environmental regulators all want to quantify the amount of nitrate leached into groundwater to better understand and manage the risk of environmental contamination from agricultural land, including grazed pasture. The ability of current technology to adequately measure the nitrate leached from a grazed paddock is tested in a stochastic simulation study. Results show that impractical numbers of samplers are needed to achieve estimates accurate to within ±20% of the true value. Rather than trying to directly measure paddock‐scale leaching under grazing, we suggest that further consideration be given to wider application of controlled application of nitrogen onto a few lysimeters and then extrapolate from the resulting measurements of leached nitrate to the paddock scale and beyond based on urine patch coverage.
Altered apoptosis regulation in Kufor–Rakeb syndrome patients with mutations in the ATP13A2 gene
Authors: Radi Elena , Formichi Patrizia , Maio Giuseppe Di , Battisti Carla , Federico Antonio
Published: November 2011

ATP13A2 gene encodes for a protein of the group 5 P‐type ATPase family. ATP13A2 mutations are responsible for Kufor–Rakeb syndrome (KRS), a rare autosomal recessive juvenile parkinsonism characterized by the subacute onset of extrapyramidal, pyramidal and cognitive dysfunction with secondary nonresponsiveness to levodopa. FBXO7 protein is an F‐box‐containing protein. Recessive FBXO7 mutations are responsible for PARK15, a rare juvenile parkinsonism characterized by progressive neurodegeneration with extrapyramidal and pyramidal system involvement. Our aim was to evaluate apoptosis in cells from two KRS siblings carrying a homozygous ATP13A2 mutation and a heterozygous FBXO7 mutation. We also analysed apoptosis in the patients’ healthy parents. Peripheral blood lymphocytes from the KRS patients and parents were exposed to 2‐deoxy‐D‐ribose; apoptosis was analysed by flow cytometry and fluorescence microscopy. Apoptosis was much higher in lymphocytes from the KRS patients and parents than in controls, both in standard conditions and after induction with a pro‐apoptotic stimulus. The lack of correlation between increased apoptosis and the presence of the mutated FBXO7 gene rules out the involvement of FBXO7 in apoptosis regulation. The altered apoptotic pattern of subjects with mutated ATP13A2 suggests a correlation between apoptosis alteration and the mutated ATP13A2 protein. We hypothesize that ATP13A2 mutations may compromise protein function, disrupting cell cation balance and rendering cells prone to apoptosis. However, the deregulation of apoptosis in KRS patients displaying different disease severity suggested that the altered apoptotic pathway probably does not have a pathogenetic role in KRS by itself.