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Iron reduction and sulfate reduction often occur simultaneously in anoxic systems, and where that is the case, the molar ratio between the reactions (i.e., Fe/SO42- reduced) influences their impact on water quality and carbon storage. Previous research has shown that pH and the supply of electron donors and acceptors affect that ratio, but it is unclear how their influences compare and affect one another. This study examines impacts of pH and the supply of acetate, sulfate, and goethite on the ratio of iron to sulfate reduction in semi-continuous sediment bioreactors. We examined which parameter had the greatest impact on that ratio and whether the parameter influences depended on the state of each other. Results show that pH had a greater influence than acetate supply on the ratio of iron to sulfate reduction, and that the impact of acetate supply on the ratio depended on pH. In acidic reactors (pH 6.0 media), the ratio of iron to sulfate reduction decreased from 3:1 to 2:1 as acetate supply increased (0-1 mM). In alkaline reactors (pH 7.5 media), iron and sulfate were reduced in equal proportions, regardless of acetate supply. Secondly, a comparison of experiments with and without sulfate shows that the extent of iron reduction was greater if sulfate reduction was occurring and that the effect was larger in alkaline reactors than acidic reactors. Thus, the influence of sulfate supply on iron reduction extent also depended on pH and suggests that iron reduction grows more dependent on sulfate reduction as pH increases. Our results compare well to trends in groundwater geochemistry and provide further evidence that pH is a major control on iron and sulfate reduction in systems with crystalline (oxyhydr)oxides. pH not only affects the ratio between the reactions but also the influences of other parameters on that ratio.

Methanogenesis and iron reduction play major roles in determining global fluxes of greenhouse gases. Despite their importance, environmental factors that influence their interactions are poorly known. Here, we present evidence that pH significantly influences the balance between each reaction in anoxic environments that contain ferric (oxyhydr)oxide minerals. In sediment bioreactors that contained goethite as a source of ferric iron, both iron reduction and methanogenesis occurred but the balance between them varied significantly with pH. Compared to bioreactors receiving acidic media (pH 6), electron donor oxidation was 85% lower for iron reduction and 61% higher for methanogenesis in bioreactors receiving alkaline media (pH 7.5). Thus, methanogenesis displaced iron reduction considerably at alkaline pH. Geochemistry data collected from U.S. aquifers demonstrate that a similar pattern also exists on a broad spatial scale in natural settings. In contrast, in bioreactors that were not augmented with goethite, clay minerals served as the source of ferric iron and the balance between each reaction did not vary significantly with pH. We therefore conclude that pH can regulate the relative contributions of microbial iron reduction and methanogenesis to carbon fluxes from terrestrial environments. We further propose that the availability of ferric (oxyhydr)oxide minerals influences the extent to which the balance between each reaction is sensitive to pH. The results of this study advance our understanding of environmental controls on microbial methane generation and provide a basis for using pH and the occurrence of ferric minerals to refine predictions of greenhouse gas fluxes.

Glucosylceramides (GlcCer), glucose-conjugated sphingolipids, are major components of the endomembrane system and plasma membrane in most eukaryotic cells. Yet the quantitative significance and cellular functions of GlcCer are not well characterized in plants and other multi-organ eukaryotes. To address this, we examined Arabidopsis lines that were lacking or deficient in GlcCer by insertional disruption or by RNA interference (RNAi) suppression of the single gene for GlcCer synthase (GCS, At2g19880), the enzyme that catalyzes GlcCer synthesis. Null mutants for GCS (designated 'gcs-1') were viable as seedlings, albeit strongly reduced in size, and failed to develop beyond the seedling stage. Heterozygous plants harboring the insertion allele exhibited reduced transmission through the male gametophyte. Undifferentiated calli generated from gcs-1 seedlings and lacking GlcCer proliferated in a manner similar to calli from wild-type plants. However, gcs-1 calli, in contrast to wild-type calli, were unable to develop organs on differentiation media. Consistent with a role for GlcCer in organ-specific cell differentiation, calli from gcs-1 mutants formed roots and leaves on media supplemented with the glucosylated sphingosine glucopsychosine, which was readily converted to GlcCer independent of GCS. Underlying these phenotypes, gcs-1 cells had altered Golgi morphology and fewer cisternae per Golgi apparatus relative to wild-type cells, indicative of protein trafficking defects. Despite seedling lethality in the null mutant, GCS RNAi suppression lines with ≤2% of wild-type GlcCer levels were viable and fertile. Collectively, these results indicate that GlcCer are essential for cell-type differentiation and organogenesis, and plant cells produce amounts of GlcCer in excess of that required for normal development.

The antiinflammatory effects of ethanol and aqueous extracts from Drosera rotundifolia and from Drosera madagascariensis were compared in vivo in the HET-CAM assay. Both extracts from D. rotundifolia and the ethanol extract from D. madagascariensis showed remarkable efficacy at doses of 500 microg/pellet. The inhibition of the inflammation by the extracts was stronger than that by 50 microg hydrocortisone/pellet. In contrast, there was only a very weak effect observed at a dose of 500 microg/pellet of the water extract from D. madagascariensis. The chemical analyses of the extracts showed that the effect cannot be attributed to naphthoquinones, but might be due to flavonoids. Ellagic acid obviously plays an important role in the antiangiogenic effect of the Drosera extracts.

Empowerment, creativity, and organizational memory are constructs that have been researched in MIS. While each construct has received individual attention, we have found relatively little research linking them. One of the major edicts of empowerment is delegation of decision making authority to lower-level employees. Increased authority allows employees more freedom to be creative. However, if creative thought is generated but not captured, innovative ideas may be lost. Organizational memory can capture creative ideas as they are generated so that empowered teams can draw upon positive creative experiences. We developed a theoretical model to illuminate the relationships between organizational memory, worker empowerment, and creativity. The model portrays the linkages between empowerment and creativity, creativity and organizational memory, and organizational memory and empowerment. The model was developed based on the literature in each respective area and an interview-based study concerning “empowered” systems development project teams and organizational memory. Analysis of the interview data revealed that empowered workers generate creative solutions to problems. However, creative solutions can only be used for future projects if they are somehow recorded into organizational memory. Organizations that empowered their workforce and embraced creativity reported increased customer satisfaction, waste reduction, and some quality gains. In contrast, those that did not empower reported little or no change. Organizations that recorded creative solutions to problems believe that retrieval of this information could be potentially useful for future projects. Potential challenges faced by organizations classified into each cell are also presented. This classification scheme should prove useful as a guide to organizations examining the potential benefits and pitfalls of worker empowerment and organizational memory.

Chronic disorders such as haemophilia and von Willebrand disease can rob people of a feeling of control over their lives. Added to this is often a feeling of confusion or intimidation when dealing with the healthcare system. People may begin to feel like victims of their disorders and of the healthcare system. The healthcare system defines people who are in receipt of care as patients. The word patient comes from the Latin word patiens, which means to suffer, endure, allow, permit or undergo. Even the term implies a sense of victimization. People who become partners in their care and view the receipt and delivery of healthcare as a service wherein they are the consumer and the doctor or clinician is the provider, will feel more in control and will likely have better outcomes than people who assume the more traditional role of 'patient'.

Plantago lanceolata L. extracts are used against inflammatory diseases. In this study we have demonstrated the ability of four liquid extracts of Plantago lanceolata L. to inhibit membrane irritation on the chick chorioallantoic membrane. We used a modified hen's egg chorioallantoic membrane test (HET-CAM), in which the membrane irritation was induced with sodium dodecyl sulphate. The antiinflammatory activity of the extracts was compared with the activity of some antiinflammatory active drugs. These extracts showed a potent activity in the inhibition of membrane irritation. © 1998 John Wiley & Sons, Ltd.

The antibody response to rabbit gamma-globulin (RGG) of high-responder, but not of low-responder Biozzi mice decreased with age. Injection with aggregate-freed RGG reduced the response of high-responder but not of low-responder mice to subsequent injections with aggregated RGG. This reduction in the antibody response, formed by high-responder mice, decreased with increasing age; aggregate-freed RGG appeared to sensitize 6-month-old low-responder mice to a subsequent injection with aggregated RGG. When animals, not pretreated with aggregate-freed RGG, were immunized with RGG and lipopolysaccharide (LPS), the immune response was greatly enhanced. The response of both pretreated low and high responders was substantially smaller than that of corresponding animals which were not given aggregate-freed RGG, prior to immunization. LPS revealed an inhibitory effect on low-responder mice of aggregate-freed RGG, which was not detected upon immunization with heat-aggregated RGG alone. The involvement of nonspecific suppressor cells and of B cell tolerance in low-responder mice is discussed.

The lymphoid cell composition of milky spots was analyzed in unprimed mice before and after i.p. immunization with sheep red blood cells. Milky spots contained surface immunoglobulin-positive B lymphocytes, and T cells of the helper and cytotoxic phenotype. After secondary antigen challenge (a) the number of lymphocytes increased up to 40-fold, (b) B and T cells were found to segregate into distinct areas in situ, and (c) lymphocytes were found to associate with I-A-negative stromal cells in vivo. These findings qualify milky spots as a peripheral lymphoid organ exhibiting a remarkable change in number and composition of lymphocytes in response to a local antigen stimulus.

In this article is presented a brief review of the work in machine translation of languages, with the conclusion that much more research needs to be done and that it does not appear that human beings will ever be relieved of the necessity of learning languages and of knowing how to use these languages effectively.

In the F1 hybrid of autoimmune New Zealand Black (NZB) and phenotypically normal New Zealand White (NZW) mice, there occurs a severe systemic lupus erythematosus (SLE)-like autoimmune disease more fulminant than that found in the parental NZB mice. To determine the role of the H-2 complex in the pathogenesis of autoimmune disease of the (NZB X NZW)F1 hybrid, we developed H-2-congenic NZB (NZB.H-2z) and NZW (NZW.H-2d) strains, and compared the degree of autoimmune features between congenic H-2d/H-2d and H-2z/H-2z homozygous F1 hybrids and the original H-2d/H-2z heterozygous (NZB X NZW)F1 hybrid. We found that autoimmune features such as productions of IgG class anti-DNA antibodies and retroviral gp70 immune complexes and the development of renal disease were to a great extent reduced in both H-2 homozygous F1 hybrids, as compared with the H-2 heterozygous (NZB X NZW)F1 hybrid. It would thus appear that the heterozygosity of H-2d haplotype derived from NZB and H-2z from NZW is essential for the autoimmune disease characteristic of the (NZB X NZW)F1 hybrid.

International audience; Wildlife movement ecology often focuses on breeders, whose territorial attachments facilitate trapping and following individuals over time. This leads to incomplete understanding of movements of individuals not actively breeding due to age, breeding failure, subordinance, and other factors. These individuals are often present in breeding populations and contribute to processes such as competition and pathogen spread. Therefore, excluding them from movement ecology studies could bias or mask important spatial dynamics. Loafing areas offer an alternative to breeding sites for capturing and tracking individuals. Such sites may allow for sampling individuals regardless of breeding status, while also avoiding disturbance of sensitive breeding areas. However, little is known about the breeding status of individuals attending loafing sites, or how their movements compare to those of breeders captured at nests. We captured a seabird, the brown skua, attending either nests or loafing areas (‘clubs’) at a multi-species seabird breeding site on Amsterdam Island (southern Indian Ocean). We outfitted skuas with GPS-UHF transmitters and inferred breeding statuses of individuals captured at clubs using movement patterns of breeders captured at nests. We then compared space use and activity patterns between breeders and nonbreeders. Both breeding and nonbreeding skuas attended clubs. Nonbreeders ranged more widely, were more active, and overlapped more with other seabirds and marine mammals than did breeders. Moreover, some nonbreeders occupied fixed territories and displayed more restricted movements than those without territories. Nonbreeders became less active over the breeding season, while activity of breeders remained stable. Nonbreeding skuas were exposed to the agent of avian cholera at similar rates to breeders but were more likely to forage in breeding areas of the endangered endemic Amsterdam albatross, increasing opportunities for interspecific pathogen transmission. Our results show that inference based only on breeders fails to capture important aspects of population-wide movement patterns. Capturing nonbreeders as well as breeders would help to improve population-level representation of movement patterns, elucidate and predict effects of external changes and conservation interventions (e.g. rat eradication) on movement patterns and pathogen spread, and develop strategies to manage outbreaks of diseases such as highly pathogenic avian influenza.; Les recherches sur l'écologie du déplacement de la faune sauvage au niveau individuel ciblent souvent des individus reproducteurs, car leur attachement territorial aux sites de reproduction facilite la capture, la recapture, et le suivi des individus à travers le temps. Au contraire, les individus qui ne reproduisent pas (à cause de leur âge, échec de reproduction, manque de dominance et autres facteurs) sont souvent exclus. Ces individus sont souvent présents aux sites de reproduction et contribuent aux processus de compétition, et de transmission des pathogènes. Par conséquence, leur exclusion des études de mouvements risque d'introduire des biais dans notre connaissance des dynamiques spatiales des populations. Les sites de repos présentent une alternative aux sites de reproduction pour la capture et suivi des individus. Ces sites présentent l'opportunité de capturer des oiseaux reproducteurs ainsi que non-reproducteurs, tout en évitant de déranger des sites sensibles de nidification. Néanmoins, les sites de repos sont peu connus, et il est difficile de déterminer si les oiseaux qui les utilisent sont reproducteurs ou non-reproducteurs, ou de savoir comment leurs mouvements se comparent à ceux d'oiseaux attrapés au nid. Nous avons capturé des oiseaux marins prédateurs, les labbes antarctiques, sur leurs nids ou sur des sites de repos partagés (« clubs »). Nous avons attaché des balises GPS-UHF aux oiseaux et avons déterminé le statut reproductif des oiseaux de statut inconnu en comparant leurs mouvements à ceux de labbes capturés au nid (et donc clairement reproducteurs). Nous avons ensuite comparé l'utilization de l'espace et les niveaux d'activité entre labbes reproducteurs et non-reproducteurs. Les labbes reproducteurs et non-reproducteurs étaient présents aux « clubs ». Comparés aux reproducteurs, les labbes non-reproducteurs utilisaient des surfaces plus grandes, étaient plus actifs, et exploitaient plus souvent des zones utilisées par d'autres espèces d'oiseaux et de mammifères marins. Par ailleurs, quelques labbes non-reproducteurs occupaient des territoires fixes et présentaient des mouvements plus limités que ceux qui n'occupaient pas de territoire. Les labbes non-reproducteurs étaient autant exposés à l'agent du choléra aviaire que les reproducteurs, mais ils se nourrissaient plus souvent dans l'habitat de l'albatros d'Amsterdam (une espèce en danger), augmentant leur probabilité de transmettre des pathogènes à cette espèce. Nos résultats montrent que les études de déplacement ne ciblant que les oiseaux reproducteurs ne représentent les déplacements de la population générale que de manière imparfaite. Capturer des oiseaux sur des sites de repos peut ainsi améliorer le taux de représentation. Le suivi des individus non-reproducteurs, de labbes ou d'autres espèces, peut aider à prédire les effets de changements des conditions externes (comme l'éradication des rats sur l'Amsterdam ou l'apparition et transmission de la grippe aviaire) qui peuvent altérer les dynamiques éco-épidemiologiques et les interactions entre espèces.

International audience; Ungulate populations exhibiting partial migration present a unique opportunity to explore the causes of the general phenomenon of migration. The European roe deer Capreolus capreolus is particularly suited for such studies due to a wide distribution range and a high level of ecological plasticity. In this study we undertook a comparative analysis of roe deer GPS location data from a representative set of European ecosystems available within the EURODEER collaborative project. We aimed at evaluating the ecological factors affecting migration tactic (i.e. occurrence) and pattern (i.e. timing, residence time, number of migratory trips). Migration occurrence varied between and within populations and depended on winter severity and topographic variability. Spring migrations were highly synchronous, while the timing of autumn migrations varied widely between regions, individuals and sexes. Overall, roe deer were faithful to their summer ranges, especially males. In the absence of extreme and predictable winter conditions, roe deer seemed to migrate opportunistically, in response to a tradeoff between the costs of residence in spatially separated ranges and the costs of migratory movements. Animals performed numerous trips between winter and summer ranges which depended on factors influencing the costs of movement such as between-range distance, slope and habitat openness. Our results support the idea that migration encompasses a behavioural continuum, with one-trip migration and residence as its end points, while commuting and multi-trip migration with short residence times in seasonal ranges are intermediate tactics. We believe that a full understanding of the variation in tactics of temporal separation in habitat use will provide important insights on migration and the factors that influence its prevalence.

International audience; Background: Statins represent candidates for drug repurposing in Parkinson's disease (PD). Few studies examined the role of reverse causation, statin subgroups, and dose–response relations based on time-varying exposures. Objectives: We examined whether statin use is associated with PD incidence while attempting to overcome the limitations described previously, especially reverse causation. Method: We used data from the E3N cohort study of French women (follow-up, 2004–2018). Incident PD was ascertained using multiple sources and validated by experts. New statin users were identified through linked drug claims. We set up a nested case-control study to describe trajectories of statin prescriptions and medical consultations before diagnosis. We used time-varying multivariable Cox proportional hazards regression models to examine the statins–PD association. Exposure indexes included ever use, cumulative duration/dose, and mean daily dose and were lagged by 5 years to address reverse causation. Results: The case-control study (693 cases, 13,784 controls) showed differences in case-control trajectories, with changes in the 5 years before diagnosis in cases. Of 73,925 women (aged 54–79 years), 524 developed PD and 11,552 started using statins in lagged analyses. Ever use of any statin was not associated with PD (hazard ratio [HR] = 0.87, 95% confidence interval [CI] = 0.67–1.11). Alternatively, ever use of lipophilic statins was significantly associated with lower PD incidence (HR = 0.70, 95% CI = 0.51–0.98), with a dose–response relation for the mean daily dose (P-linear trend = 0.02). There was no association for hydrophilic statins. Conclusion: Use of lipophilic statins at least 5 years earlier was associated with reduced PD incidence in women, with a dose–response relation for the mean daily dose. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

Risk of death from undernutrition is thought to be higher in younger than in older children, but evidence is mixed. Research also demonstrates sex differences whereby boys have a higher prevalence of undernutrition than girls. This analysis described mortality risk associated with anthropometric deficits (wasting, underweight and stunting) in children 6–59 months by age and sex. We categorised children into younger (6–23 months) and older (24–59 months) age groups. Age and sex variations in near-term (within 6 months) mortality risk, associated with individual anthropometric deficits were assessed in a secondary analysis of multi-country cohort data. A random effects meta-analysis was performed. Data from seven low-or-middle-income-countries collected between 1977 and 2013 were analysed. One thousand twenty deaths were recorded for children with anthropometric deficits. Pooled meta-analysis estimates showed no differences by age in absolute mortality risk for wasting (RR 1.08, p = 0.826 for MUAC < 125 mm; RR 1.35, p = 0.272 for WHZ < −2). For underweight and stunting, absolute risk of death was higher in younger (RR 2.57, p < 0.001) compared with older children (RR 2.83, p < 0.001). For all deficits, there were no differences in mortality risk for girls compared with boys. There were no differences in the risk of mortality between younger and older wasted children, supporting continued inclusion of all children under-five in wasting treatment programmes. The risk of mortality associated with underweight and stunting was higher among younger children, suggesting that prevention programmes might be justified in focusing on younger children where resources are limited. There were no sex differences by age in mortality risk for all deficits.

How precise should accounting measurements be, if management has discretion to strategically withhold? We examine this question by nesting an optimal persuasion mechanism, which controls what measurements are conducted, within a voluntary disclosure framework a la Dye (85) and Jung and Kwon (1988). In our setting, information has real effects because the firm uses it to make a continuous operating decision, increasing in the market's belief. Absent frictions other than uncertainty about information endowment, we show that imprecision can reduce strategic withholding but always decreases firm value. We then examine plausible environments under which, by contrast, there is an optimal level of imprecision featuring coarseness at the marginal discloser. We offer additional implications in the contexts of enforcement against strategic withholding and financing with collateralized assets.

We show that the feasibility of a booking in the European entry-exit gas market can be decided in polynomial time on single-cycle networks that are passive, i.e. do not contain controllable elements. The feasibility of a booking can be characterized by solving polynomially many nonlinear potential-based flow models for computing so-called potential-difference maximizing load flow scenarios. We thus analyze the structure of these models and exploit both the cyclic graph structure as well as specific properties of potential-based flows. This enables us to solve the decision variant of the nonlinear potential-difference maximization by reducing it to a system of polynomials of constant dimension that is independent of the cycle's size. This system of fixed dimension can be handled with tools from real algebraic geometry to derive a polynomial-time algorithm. The characterization in terms of potential-difference maximizing load flow scenarios then leads to a polynomial-time algorithm for deciding the feasibility of a booking. Our theoretical results extend the existing knowledge about the complexity of deciding the feasibility of bookings from trees to single-cycle networks., SCOPUS: ar.j, info:eu-repo/semantics/published