82 research outputs found
Evaluating inland valley agro-ecosystems in Ghana using a multi-scale characterization approach
As part of measures for improving the productive capacities of inland valley systems for rice-based cropping systems, a published multi-scale characterization approach was used in Ghana to assess the constraints and variables which must be understood before agronomic interventions are made. Macro, reconnaissance, semidetailed and detailed levels of characterization at their respective scales were used. Between 1996 and 1999, Geographical Information System (GIS) and transect studies were carried out, after which the extent of variability in the biotic and abiotic characteristics of two agro-ecologies were identified. Ten agro-ecological units were identified for Ghana based on map overlays
and cluster analysis. The method allowed for the selection of Mankran and Jolo-Kwaha watersheds representing the equatorial and savanna agro-ecologies, respectively. Socio-economic parameters (markets, population density and suchlike) were recognized as the
essential variables, which should be considered alongside lithology, climate, hydrology and others, for the choice of valleys for development interventions for crop production. At the detailed level of characterization, hydrological and soil characteristics underscored the need
to properly understand the watershed-level and valleyspecific constraints before meaningful rice-based research and cropping systems are developed.En tant que partie de mesures pour améliorer les capacités productives de systémes de vallée de l\'intérieur pour les systèmes de culture basés sur le riz, une approche de caractérisation multiéchelle publiée était employée au Ghana en vue d\'estimer les contraintes et les variables qu\'il faut comprendre avant que les interventions agronomiques soient faites. Les niveaux
macro, reconnaissance, semi-détaillé et détaillé de caractérisation à leurs échelles respectives étaient utilisés. Entre 1996 et 1999, l\'étude transversale et du Système
Informationnel Géographique (SIG) étaient faites à la suite de quelle l\'étendue de variabilité de caractéristiques biotiques et abiotiques de deux agro-écologies étaient identifiées. Dix unités agro-écologiques étaient identifiées pour le Ghana basé sur l\'analyse de revêtements et de rassemblement sur la carte. La méthode permettait la
sélection de lignes de partage des eaux de Mankran et de Jolo-Kwaha représentant respectivement les agroécologies équatoriales et savanes. Les paramètres socioéconomiques (les marchés, la densité de population, etc.) étaient reconnus comme les variables essentielles, qui devraient être considéré à côté de la lithologie, le climat,
la hydrologie, etc.; pour le choix de vallées pour les interventions de développement pour la production des cultures. Au niveau détaillé de caractérisation, les caractéristiques de hydrologie et de sol soulignent la nécessité de comprendre vraiment les contraintes de
niveaux de lignes de partage des eaux et les contraintes spécifiques à certaines vallées avant que la recherche et les systèmes de culture utiles basés sur le riz soient
développés. Ghana Journal of Agricultural Science Vol. 40 (2) 2008: pp. 141-15
Consumer confidence indices and stock markets’ meltdowns
Consumer confidence indices (CCIs) are a closely monitored barometer of countries’ economic health and an informative forecasting tool. Using European and US data, we provide a case study of the two recent stock market meltdowns (the post-dotcom bubble correction of 2000–2002 and the 2007–2009 decline at the beginning of the financial crisis) to contribute to the discussion on their appropriateness as proxies for stock markets’ investor sentiment. Investor sentiment should positively covary with stock market movements (DeLong, Shleifer, Summers, and Waldmann 1990); however, we find that the CCI–stock market relationship is not universally positive.We also do not find support for the information effect documented in the previous literature, but identify a more subtle relationship between consumer expectations about future household finances and stock market fluctuations
What's normal? Oligosaccharide concentrations and profiles in milk produced by healthy women vary geographically.
Background: Human milk is a complex fluid comprised of myriad substances, with one of the most abundant substances being a group of complex carbohydrates referred to as human milk oligosaccharides (HMOs). There has been some evidence that HMO profiles differ in populations, but few studies have rigorously explored this variability.Objectives: We tested the hypothesis that HMO profiles differ in diverse populations of healthy women. Next, we examined relations between HMO and maternal anthropometric and reproductive indexes and indirectly examined whether differences were likely related to genetic or environmental variations.Design: In this cross-sectional, observational study, milk was collected from a total of 410 healthy, breastfeeding women in 11 international cohorts and analyzed for HMOs by using high-performance liquid chromatography.Results: There was an effect of the cohort (P 4 times higher in milk collected in Sweden than in milk collected in rural Gambia (mean ± SEM: 473 ± 55 compared with 103 ± 16 nmol/mL, respectively; P < 0.05), and disialyllacto-N-tetraose (DSLNT) concentrations ranged from 216 ± 14 nmol/mL (in Sweden) to 870 ± 68 nmol/mL (in rural Gambia) (P < 0.05). Maternal age, time postpartum, weight, and body mass index were all correlated with several HMOs, and multiple differences in HMOs [e.g., lacto-N-neotetrose and DSLNT] were shown between ethnically similar (and likely genetically similar) populations who were living in different locations, which suggests that the environment may play a role in regulating the synthesis of HMOs.Conclusions: The results of this study support our hypothesis that normal HMO concentrations and profiles vary geographically, even in healthy women. Targeted genomic analyses are required to determine whether these differences are due at least in part to genetic variation. A careful examination of sociocultural, behavioral, and environmental factors is needed to determine their roles in this regard. This study was registered at clinicaltrials.gov as NCT02670278
Finding regions of interest on toroidal meshes
Fusion promises to provide clean and safe energy, and a considerable amount of research effort is underway to turn this aspiration intoreality. This work focuses on a building block for analyzing data produced from the simulation of microturbulence in magnetic confinementfusion devices: the task of efficiently extracting regions of interest. Like many other simulations where a large amount of data are produced,the careful study of ``interesting'' parts of the data is critical to gain understanding. In this paper, we present an efficient approach forfinding these regions of interest. Our approach takes full advantage of the underlying mesh structure in magnetic coordinates to produce acompact representation of the mesh points inside the regions and an efficient connected component labeling algorithm for constructingregions from points. This approach scales linearly with the surface area of the regions of interest instead of the volume as shown with bothcomputational complexity analysis and experimental measurements. Furthermore, this new approach is 100s of times faster than a recentlypublished method based on Cartesian coordinates
Key genetic variants associated with variation of milk oligosaccharides from diverse human populations
Human milk oligosaccharides (HMO), the third most abundant component of human milk, are thought to be important contributors to infant health. Studies have provided evidence that geography, stage of lactation, and Lewis and secretor blood groups are associated with HMO profile. However, little is known about how variation across the genome may influence HMO composition among women in various populations. In this study, we performed genome-wide association analyses of 395 women from 8 countries to identify genetic regions associated with 19 different HMO. Our data support FUT2 as the most significantly associated (PÂ <Â 4.23-9 to PÂ <Â 4.5-70) gene with seven HMO and provide evidence of balancing selection for FUT2. Although polymorphisms in FUT3 were also associated with variation in lacto-N-fucopentaose II and difucosyllacto-N-tetrose, we found little evidence of selection on FUT3. To our knowledge, this is the first report of the use of genome-wide association analyses on HMO
Updated consensus guidelines on the management of Phelan–McDermid syndrome
Phelan–McDermid syndrome (PMS) is a genetic condition caused by SHANK3 haploinsufficiency and characterized by a wide range of neurodevelopmental and systemic manifestations. The first practice parameters for assessment and monitoring in individuals with PMS were published in 2014; recently, knowledge about PMS has grown significantly based on data from longitudinal phenotyping studies and large-scale genotype–phenotype investigations. The objective of these updated clinical management guidelines was to: (1) reflect the latest in knowledge in PMS and (2) provide guidance for clinicians, researchers, and the general community. A taskforce was established with clinical experts in PMS and representatives from the parent community. Experts joined subgroups based on their areas of specialty, including genetics, neurology, neurodevelopment, gastroenterology, primary care, physiatry, nephrology, endocrinology, cardiology, gynecology, and dentistry. Taskforce members convened regularly between 2021 and 2022 and produced specialty-specific guidelines based on iterative feedback and discussion. Taskforce leaders then established consensus within their respective specialty group and harmonized the guidelines. The knowledge gained over the past decade allows for improved guidelines to assess and monitor individuals with PMS. Since there is limited evidence specific to PMS, intervention mostly follows general guidelines for treating individuals with developmental disorders. Significant evidence has been amassed to guide the management of comorbid neuropsychiatric conditions in PMS, albeit mainly from caregiver report and the experience of clinical experts. These updated consensus guidelines on the management of PMS represent an advance for the field and will improve care in the community. Several areas for future research are also highlighted and will contribute to subsequent updates with more refined and specific recommendations as new knowledge accumulates
Comparison of Two Approaches for the Metataxonomic Analysis of the Human Milk Microbiome.
Recent work has demonstrated the existence of large inter-individual and inter-population variability in the microbiota of human milk from healthy women living across variable geographical and socio-cultural settings. However, no studies have evaluated the impact that variable sequencing approaches targeting different 16S rRNA variable regions may have on the human milk microbiota profiling results. This hampers our ability to make meaningful comparisons across studies. In this context, the main purpose of the present study was to re-process and re-sequence the microbiome in a large set of human milk samples (n = 412) collected from healthy women living at diverse international sites (Spain, Sweden, Peru, United States, Ethiopia, Gambia, Ghana and Kenya), by targeting a different 16S rRNA variable region and reaching a larger sequencing depth. Despite some differences between the results obtained from both sequencing approaches were notable (especially regarding alpha and beta diversities and Proteobacteria representation), results indicate that both sequencing approaches revealed a relatively consistent microbiota configurations in the studied cohorts. Our data expand upon the milk microbiota results we previously reported from the INSPIRE cohort and provide, for the first time across globally diverse populations, evidence of the impact that different DNA processing and sequencing approaches have on the microbiota profiles obtained for human milk samples. Overall, our results corroborate some similarities regarding the microbial communities previously reported for the INSPIRE cohort, but some differences were also detected. Understanding the impact of different sequencing approaches on human milk microbiota profiles is essential to enable meaningful comparisons across studies. Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT02670278
Variation in Human Milk Composition Is Related to Differences in Milk and Infant Fecal Microbial Communities.
Previously published data from our group and others demonstrate that human milk oligosaccharide (HMOs), as well as milk and infant fecal microbial profiles, vary by geography. However, little is known about the geographical variation of other milk-borne factors, such as lactose and protein, as well as the associations among these factors and microbial community structures in milk and infant feces. Here, we characterized and contrasted concentrations of milk-borne lactose, protein, and HMOs, and examined their associations with milk and infant fecal microbiomes in samples collected in 11 geographically diverse sites. Although geographical site was strongly associated with milk and infant fecal microbiomes, both sample types assorted into a smaller number of community state types based on shared microbial profiles. Similar to HMOs, concentrations of lactose and protein also varied by geography. Concentrations of HMOs, lactose, and protein were associated with differences in the microbial community structures of milk and infant feces and in the abundance of specific taxa. Taken together, these data suggest that the composition of human milk, even when produced by relatively healthy women, differs based on geographical boundaries and that concentrations of HMOs, lactose, and protein in milk are related to variation in milk and infant fecal microbial communities
Corrigendum: What's Normal? Microbiomes in Human Milk and Infant Feces Are Related to Each Other but Vary Geographically: The INSPIRE Study
A correction has been made to the Materials and Methods section, subsection Extraction of DNA fromMilk, paragraph 2, The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated
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