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Performance optimization for parallel loop-oriented programs compromises between parallelism and locality. We present a visualization interface that allows programmers to assist the compiler in generating optimal code. It greatly improves the user's understanding of the transformations that took place and aids in making additional transformations in a visually intuitive way. [ABSTRACT FROM AUTHOR]

Background. Lebanon has a need for innovative approaches to increase access to mental health care to meet the country's current high demand. E-mental health has been included in its national mental health strategy while in parallel the World Health Organization has produced an online intervention called 'Step-by-Step' to treat symptoms of depression that is being tested in Lebanon over the coming years. Aim. The primary aim of this study is to conduct bottom-up, community-driven qualitative cognitive interviewing from a multi-stakeholder perspective to inform the cultural adaptation of an Internet-delivered mental health intervention based on behavioural activation in Lebanon. Methods. National Mental Health Programme staff conducted a total of 11 key informant interviews with three mental health professionals, six front-line workers in primary health care centres (PHCCs) and two community members. Also, eight focus group discussions, one with seven front-line workers and seven others with a total of 66 community members (Lebanese, Syrians and Palestinians) were conducted in several PHCCs to inform the adaptation of Step-by-Step. Results were transcribed and analysed thematically by the project coordinator and two research assistants. Results. Feedback generated from the cognitive interviewing mainly revolved around amending the story, illustrations and the delivery methods to ensure relevance and sensitivity to the local context. The results obtained have informed major edits to the content of Step-by-Step and also to the model of provision. Notably, the intervention was made approximately 30% shorter; it includes additional videos of content alongside the originally proposed comic book- style delivery; there is less emphasis on total inactivity as a symptom of low mood and more focus on enjoyable activities to lift mood; the story and ways to contact participants to provide support were updated in line with local gender norms; and many of the suggested or featured activities have been revised in line with suggestions from community members. Conclusions. These findings promote and advocate the use of community-driven adaptation of evidence-based psychological interventions. Some of the phenomena recorded mirror findings from other research about barriers to care seeking in the region and so changes made to the intervention should be useful in improving utility and uptake of 'Step-by-Step'. [ABSTRACT FROM AUTHOR]

The population of (Haliaeetus vocifer (Daudin)) at Lake Naivasha, Kenya, was censused over a 13-year period (1987-99). During this time it declined by over half, to alow of 70 birds, by 1996. Breeding effectively ceased, with no courtship or nesting observed for most of the 1990s. The reason seemed to be a food shortage, which provided enough to stay alive but not enough to breed. Declines in the main prey items - fish species and red knobbed coot (Fulica cristata), occurred during the early 1990s and feeding conditions were worsened by a combination of increased turbidity in the lake, floating mats of exotic vegetation and the loss of shallow lagoons behind fringing Cyperus papyrus. This explanation was confirmed when heavy rains, following the strong ENSO event in 1997-98, caused a rapid lake level rise of 3 m vertically, flooding new lagoons behind formerly stranded C. papyrus. Breeding re-commenced, leading to 17-24 fledged juveniles in a population exceeding 100, by 1999. This population of H. vocifer is a valuable index of both the health of the lake and of its littoral ecotone. [ABSTRACT FROM AUTHOR]

This paper reviews North Atlantic shelf seas palaeoclimate during the interval 4–3Ma, prior to and incorporating the ‘Mid-Pliocene warm period’ (ca 3.29–2.97Ma). Fossil assemblages and stable isotope data demonstrate northwards extension of subtropical faunas along the coast of the Carolinas–Virginia (Yorktown and Duplin Formations) relative to the present day, suggesting a more vigorous Florida Current, with reduced seasonality and warm water extending north of Cape Hatteras (reconstructed annual range for Virginia 12–30°C). This interpretation supports conceptual models of increased meridional heat transport for the Pliocene. Sea temperatures for Florida (Lower Pinecrest Beds) were similar to or slightly cooler than (summers 25–27°C) today, and were probably influenced by seasonal upwelling of cold deep water. Reduced seasonality is also apparent in the Coralline Crag Formation of the southern North Sea, with ostracods suggesting winter sea temperatures of 10°C (modern 4°C). However, estimates from Pliocene bivalves (3.6–16.6°C) are similar to or cooler than the present day. This ‘mixed’ signal is problematic given warmer seas in the Carolinas–Virginia, and climate model and oceanographic data that show warmer seas in the ‘Mid-Pliocene’ eastern North Atlantic. This may be because the Coralline Crag Formation was deposited prior to peak Mid-Pliocene warmth. [ABSTRACT FROM AUTHOR]

SUMMARYInternal browning disorders, including brown fleck (BF), in potato (Solanum tuberosum) tubers greatly reduce tuber quality, but the causes are not well understood. This is due, in part, to the highly variable data provided by visual value-based rating systems. A digital imaging technique was developed to quantify accurately the incidence of internal browning in potato tubers. Images of tuber sections were scanned using a flatbed scanner and digitally enhanced to highlight tuber BF lesions, and the area of affected tissue calculated using pixel quantification software. Digital imaging allowed for the determination of previously unused indices of the incidence and severity of internal browning in potato tubers. Statistical analysis of the comparison between digitally derived and visual-rating BF data from a glasshouse experiment showed that digital data greatly improved the delineation of treatment effects. The F-test probability was further improved through square root or logarithmic data transformations of the digital data, but not of the visual-rating data. Data from a field experiment showed that the area of tuber affected by BF and the number of small BF lesions increased with time and with increase in tuber size. The results from this study indicate that digital imaging of internal browning disorders of potato tubers holds much promise in determining their causes that heretofore have proved elusive. [ABSTRACT FROM AUTHOR]

Background information. Accurate sorting of proteins to the three types of secretory granules in Toxoplasma gondii is crucial for successful cell invasion by this obligate intracellular parasite. As in other eukaryotic systems, propeptide sequences are a common yet poorly understood feature of proteins destined for regulated secretion, which for Toxoplasma occurs through two distinct invasion organelles, rhoptries and micronemes. Microneme discharge during parasite apical attachment plays a pivotal role in cell invasion by delivering adhesive proteins for host receptor engagement.Results. We show here that the small micronemal proprotein MIC5 (microneme protein-5) undergoes proteolytic maturation at a site beyond the Golgi, and only the processed form of MIC5 is secreted via the micronemes. Proper cleavage of the MIC5 propeptide relies on an arginine residue in the P1′ position, although P1′ mutants are still cleaved to a lesser extent at an alternative site downstream of the primary site. Nonetheless, this aberrantly cleaved species still correctly traffics to the micronemes, indicating that correct cleavage is not necessary for micronemal targeting. In contrast, a deletion mutant lacking the propeptide was retained within the secretory system, principally in the ER (endoplasmic reticulum). The MIC5 propeptide also supported correct trafficking when exchanged for the M2AP propeptide, which was recently shown to also be required for micronemal trafficking of the TgMIC2 (T. gondii MIC2)–M2AP complex [Harper, Huynh, Coppens, Parussini, Moreno and Carruthers (2006) Mol. Biol. Cell 17, 4551–4563].Conclusion. Our results illuminate common and unique features of micronemal propeptides in their role as trafficking facilitators. [ABSTRACT FROM AUTHOR]

Congenital central hypoventilation syndrome (CCHS) patients show impaired ventilatory responses and loss of breathlessness to hypercapnia, yet arouse from sleep to high CO2, suggesting intact chemoreceptor afferents. The syndrome provides a means to differentiate brain areas controlling aspects of breathing. We used functional magnetic resonance imaging to determine brain structures responding to inspired 5% CO2-95% O2 in 14 CCHS patients and 14 controls. Global signal changes induced by the challenge were removed on a voxel-by-voxel basis. A priori-defined volume-of-interest time trends (assessed with repeated measures ANOVA) and cluster analysis based on modeling each subject to a step function (individual model parameter estimates evaluated with t-test, corrected for multiple comparisons) revealed three large response clusters to hypercapnia distinguishing the two groups, extending from the 1) posterior thalamus through the medial midbrain to the dorsolateral pons, 2) right caudate nucleus, ventrolaterally through the putamen and ventral insula to the mid-hippocampus, and 3) deep cerebellar nuclei to the dorsolateral cerebellar cortex bilaterally. Smaller clusters and defined areas of group signal differences in the midline dorsal medulla, amygdala bilaterally, right dorsal-posterior temporal cortex, and left anterior insula also emerged. In most sites, early transient or sustained responses developed in controls, with little, or inverse change in CCHS subjects. Limbic and medullary structures regulating responses to hypercapnia differed from those previously shown to mediate loaded breathing ventilatory response processing. The findings show the significant roles of cerebellar and basal ganglia sites in responding to hypercapnia and the thalamic and midbrain participation in breathing control. [ABSTRACT FROM AUTHOR]

1. This paper advocates a catchment-scale perspective for river restoration and for individual rehabilitation works even though, at present, such works are often small-scale and ad hoc in nature. The catchment-scale approach is the logical consequence of the application of fundamental principles of river science to the philosophy of river restoration. 2. The five principles that river restoration should incorporate are: i) the hierarchy of river systems; ii) the proportional relationships between discharge and channel dimensions; iii) the importance of the physical and biological continua of natural rivers; iv) the four-dimensional nature of river systems; and v) the role of heterogeneity in maintaining biodiversity and that of disturbance in maintaining heterogeneity. 3. Two sets of examples are given to illustrate the need for these five principles. One set relates to the role of trees in river processes (and in river restoration), while the other relates to the rehabilitation of physical structures in rivers at a different scale. 4. The value of trees both for the maintenance of water quality and for their conservation value in upper-order rivers is demonstrated. This, combined with evidence elsewhere for trees as an integral part of the river-riparian ecotone, suggests the restoration of lowland headwater streams as being totally tree-influenced. In middle and lower reaches of rivers, it is important to restore the river–floodplain interactions. Continuity with groundwater through the hyporheos as a result of riffle-pool rehabilitation and flood-regeneration of meadows and alluvial forests should be the long-term vision for lower-reach restoration. 5. In the interim, piecemeal rehabilitation of the physical heterogeneity of the bed and banks in large rivers can be locally successful provided that it restores coarse particles and interstices where they are absent through artificial material and/or siltation, but not if it fails to recognize fully the importance of replacing lost heterogeneity. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

1. This paper examines the influence of channel morphology and hydraulics on the occurrence and diversity of ‘functional habitats’ (also called ‘meso-habitats’) in semi-natural and physically degraded rivers. 2. The depths and velocities at which each functional habitat is most likely to be found are described using ‘occurrence matrices’. In most cases, each habitat was associated with distinct depth-velocity conditions. 3. The relationship between habitat occurrence, diversity and river degradation was examined. The deviation of a site from its predicted natural summer wetted width was used as an index of physical degradation. Habitat diversity (measured as the Shannon index) was low for sites that were wider than expected for natural conditions. This was independent of the type of physical perturbation causing the width deviation. 4. Two main types of physical perturbation were identified in the degraded river: over-widening and ponding. Over-widened sites were shallow, slow and dominated by silt and emergent macrophyte habitats. Ponded sites were deep, slow and dominated by floating-leaved macrophyte and macroalgal habitats. 5. River reaches of uniform depth had low habitat diversity compared with reaches containing both shallow and deep areas. 6. It is recommended that objective assessment of the type and extent of physical degradation, prior to restoration, should be made by measurement of depth, velocity, width and functional habitat distribution. Changes in channel morphology should then be designed to create the necessary range of depths and widths, and therefore velocities and habitat types, deemed desirable for that river site. Habitats that are over-dominant or rare can be identified and the ‘occurrence matrices’ used to inform decisions about the change in physical conditions needed to enhance or suppress that habitat. 7. The approach is a cost-effective way to link ecology with morphology and hydrology in river channel rehabilitation. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

From our Secret Lives of Cepheids program, the prototype Classical Cepheid, δ Cep, is found to be an X-ray source with periodic pulsation-modulated X-ray variations. This finding complements our earlier reported phase-dependent FUV–UV emissions of the star that increase ∼10–20 times with highest fluxes at , just prior to maximum brightness. Previously δ Cep was found as potentially X-ray variable, using XMM-Newton observations. Additional phase-constrained data were secured with Chandra near X-ray emission peak, to determine if the emission and variability were pulsation-phase-specific to δ Cep and not transient or due to a possible coronally active, cool companion. The Chandra data were combined with prior XMM-Newton observations, and were found to very closely match the previously observed X-ray behavior. From the combined data set, a ∼4 increase in X-ray flux is measured, reaching a peak = 1.7 × 1029 erg s−1 near 0.45ϕ. The precise X-ray flux phasing with the star’s pulsation indicates that the emissions arise from the Cepheid and not from a companion. However, it is puzzling that the maximum X-ray flux occurs ∼0.5ϕ (∼3 days) later than the FUV–UV maximum. There are several other potential Cepheid X-ray detections with properties similar to δ Cep, and comparable X-ray variability is indicated for two other Cepheids: β Dor and V473 Lyr. X-ray generating mechanisms in δ Cep and other Cepheids are discussed. If additional Cepheids are confirmed to show phased X-ray variations, then δ Cep will be the prototype of a new class of pulsation-induced X-ray variables. [ABSTRACT FROM AUTHOR]

We present a NASA-DLR SOFIA-Echelon Cross Echelle Spectrograph (EXES) and NASA Infrared Telescope Facility-Texas Echelon Cross Echelle Spectrograph (TEXES) mid-IR spectral study of forbidden Fe ii transitions in the early-type M supergiants, Betelgeuse (α Ori: M2 Iab) and Antares (α Sco: M1 Iab + B3 V). With EXES, we spectrally resolve the ground term [Fe ii] 25.99 μm (: K) emission from Betelgeuse. We find a small centroid blueshift of 1.9 ± 0.4 that is a significant fraction (20%) of the current epoch wind speed, with a FWHM of 14.3 ± 0.1 . The TEXES observations of [Fe ii] 17.94 μm (: K) show a broader FWHM of 19.1 ± 0.2 , consistent with previous observations, and a small redshift of 1.6 ± 0.6 with respect to the adopted stellar center-of-mass velocity of . To produce [Fe ii] 25.99 μm blueshifts of 20% wind speed requires that the emission arises closer to the star than existing thermal models for α Ori’s circumstellar envelope predict. This implies a more rapid wind cooling to below 500 K within ( mas, dist = 200 pc) of the star, where the wind has also reached a significant fraction of the maximum wind speed. The line width is consistent with the turbulence in the outflow being close to the hydrogen sound speed. EXES observations of [Fe ii] 22.90 μm (: K) reveal no emission from either star. These findings confirm the dominance of cool plasma in the mixed region where hot chromospheric plasma emits copiously in the UV, and they also constrain the wind heating produced by the poorly understood mechanisms that drive stellar outflows from these low variability and weak-dust signature stars. [ABSTRACT FROM AUTHOR]

We report on an ultraviolet spectroscopic survey of red giants observed by the Hubble Space Telescope, focusing on spectra of the Mg ii h and k lines near 2800 Å in order to study stellar chromospheric emission, winds, and astrospheric absorption. We focus on spectral types between K2 III and M5 III, a spectral type range with stars that are noncoronal, but possessing strong, chromospheric winds. We find a very tight relation between Mg ii surface flux and photospheric temperature, supporting the notion that all K2-M5 III stars are emitting at a basal flux level. Wind velocities (Vw) are generally found to decrease with spectral type, with Vw decreasing from ∼40 km s−1 at K2 III to ∼20 km s−1 at M5 III. We find two new detections of astrospheric absorption, for σ Pup (K5 III) and γ Eri (M1 III). This absorption signature had previously only been detected for α Tau (K5 III). For the three astrospheric detections, the temperature of the wind after the termination shock (TS) correlates with Vw, but is lower than predicted by the Rankine–Hugoniot shock jump conditions, consistent with the idea that red giant TSs are radiative shocks rather than simple hydrodynamic shocks. A full hydrodynamic simulation of the γ Eri astrosphere is provided to explore this further. [ABSTRACT FROM AUTHOR]

Epidemiologists have grouped the multiple disorders that lead to preterm delivery before the 28th week of gestation in a variety of ways. The authors sought to identify characteristics that would help guide how to classify disorders that lead to such preterm delivery. They enrolled 1,006 women who delivered a liveborn singleton infant of less than 28 weeks gestation at 14 centers in the United States between 2002 and 2004. Each delivery was classified by presentation: preterm labor (40%), prelabor premature rupture of membranes (23%), preeclampsia (18%), placental abruption (11%), cervical incompetence (5%), and fetal indication/intrauterine growth restriction (3%). Using factor analysis (eigenvalue = 1.73) to compare characteristics identified by standardized interview, chart review, placental histology, and placental microbiology among the presentation groups, the authors found 2 broad patterns. One pattern, characterized by histologic chorioamnionitis and placental microbe recovery, was associated with preterm labor, prelabor premature rupture of membranes, placental abruption, and cervical insufficiency. The other, characterized by a paucity of organisms and inflammation but the presence of histologic features of dysfunctional placentation, was associated with preeclampsia and fetal indication/intrauterine growth restriction. Disorders leading to preterm delivery may be separated into two groups: those associated with intrauterine inflammation and those associated with aberrations of placentation. [ABSTRACT FROM AUTHOR]