1,803 research outputs found
Nutritional intake and food sources in an adult urban Kenyan population
Urbanisation is hastening the transition from traditional food habits to less healthy diets, which are becoming more common among Kenyans. No up-to-date studies on usual dietary intake and the main food sources of adult Kenyans are available. The aim of the present study was to identify the main food sources of nutrients in the diet of urban adult Kenyans and explore potential associations with demographic variables including age, sex, level of education, occupation and body mass index. The study adopted a cross-sectional design. The dietary intake of 486 adult Kenyans from Nairobi was assessed using a validated, culture-sensitive, semi-quantitative food frequency questionnaire. Binary logistic regression models were used to evaluate associations between food sources and demographic variables. Macronutrient intakes as a proportion of total energy intake (TEI) were within international dietary guidelines. Cereals and grain products (34.0%), sugar, syrups, sweets and snacks (9.8%), fruits (9.7%) and meat and eggs (8.8%) were the major contributors to TEI. Cereals and grain products contributed 42.5% to carbohydrates, followed by fruits (12.4%) and sugar, syrups, sweets and snacks (10.6%). The most important sources of protein and total fat were cereals and grain products (23.3% and 19.7%, respectively) and meat and eggs (22.0% and 18.7%, respectively). Sex, age and level of education were associated with the choice of food groups. Although macronutrient intakes were within guidelines, the Kenyan diet was revealed to be high in sugars, salt and fibre, with differences in food sources according to demographic variables. These results can act as an incentive to national authorities to implement nutritional strategies aiming to raise awareness of healthier dietary patterns among Kenyans. © 2022 The Authors. Nutrition Bulletin published by John Wiley & Sons Ltd on behalf of British Nutrition Foundation.This work was supported by National Funds from FCT – ‘Fundação para a Ciência e a Tecnologia’ through project ‘Optimization of fermentation processes for the development of fibre‐rich cereals‐based products: promotion of fibre intake in Africa and Europe’ (ERA‐AFR/0002/2013 BI_I), the doctoral grant ‘Dietary fibre intake and tailored fermentation toward the development of functional cereal fibre‐rich food products: bridge between Africa and Europe’ (SFRH/BD/133084/2017), and also through project UIDB/50016/2020
Organophosphorous pesticide breakdown products in house dust and children’s urine.
Human exposure to preformed dialkylphosphates (DAPs) in food or the environment may affect the reliability of DAP urinary
metabolites as biomarkers of organophosphate (OP) pesticide exposure. We conducted a study to investigate the presence of DAPs in indoor residential environments and their association with children’s urinary DAP levels. We collected dust samples from homes in farmworker and urban communities (40 homes total, n=79 samples) and up to two urine samples from resident children ages 3-6 years. We measured six DAPs in all samples and eight DAP-devolving OP pesticides in a subset of dust samples (n=54). DAPs were detected in dust with diethylphosphate (DEP) being the most frequently detected (>=60%); detection frequencies for other DAPs were 0.05). Detection of DEP, chlorpyrifos, or diazinon, was not associated with DEP and/or DEPþdiethylthiophosphate detection in urine (Kappa coefficients=-0.33 to 0.16). Finally, estimated nondietary ingestion intake from DEP in dust was found to be <=5% of the dose calculated from DEP levels in urine, suggesting that ingestion of dust is not a significant source of DAPs in urine if they are excreted unchanged.This work was supported by EPA (RD 83171001) and NIEHS (PO1 ES009605). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the EPA, NIEHS, or other funders. Additional support was provided
by an EPA STAR Doctoral Fellowship (F5D30812), the University of California Institute for Mexico and the United States (UC MEXUS), and the Center for Latino Policy Research at the University of California at Berkeley
Advances in understanding of air-sea exchange and cycling of greenhouse gases in the upper ocean
\ua9 2024 University of California Press. All rights reserved. The air–sea exchange and oceanic cycling of greenhouse gases (GHG), including carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), carbon monoxide (CO), and nitrogen oxides (NOx \ubc NO \ufe NO2), are fundamental in controlling the evolution of the Earth’s atmospheric chemistry and climate. Significant advances have been made over the last 10 years in understanding, instrumentation and methods, as well as deciphering the production and consumption pathways of GHG in the upper ocean (including the surface and subsurface ocean down to approximately 1000 m). The global ocean under current conditions is now well established as a major sink for CO2, a major source for N2O and a minor source for both CH4 and CO. The importance of the ocean as a sink or source of NOx is largely unknown so far. There are still considerable uncertainties about the processes and their major drivers controlling the distributions of N2O, CH4, CO, and NOx in the upper ocean. Without having a fundamental understanding of oceanic GHG production and consumption pathways, our knowledge about the effects of ongoing major oceanic changes—warming, acidification, deoxygenation, and eutrophication—on the oceanic cycling and air–sea exchange of GHG remains rudimentary at best. We suggest that only through a comprehensive, coordinated, and interdisciplinary approach that includes data collection by global observation networks as well as joint process studies can the necessary data be generated to (1) identify the relevant microbial and phytoplankton communities, (2) quantify the rates of ocean GHG production and consumption pathways, (3) comprehend their major drivers, and (4) decipher economic and cultural implications of mitigation solutions
Techniques for Arbuscular Mycorrhiza Inoculum Reduction
It is well established that arbuscular mycorrhizal (AM) fungi can play a significant role in sustainable crop production and environmental conservation. With the increasing awareness of the ecological significance of mycorrhizas and their diversity, research needs to be directed away from simple records of their occurrence or casual speculation of their function (Smith and Read 1997). Rather, the need is for empirical studies and investigations of the quantitative aspects of the distribution of different types and their contribution to the function of ecosystems.
There is no such thing as a fungal effect or a plant effect, but there is an interaction between both symbionts. This results from the AM fungi and plant community size and structure, soil and climatic conditions, and the interplay between all these factors (Kahiluoto et al. 2000). Consequently, it is readily understood that it is the problems associated with methodology that limit our understanding of the functioning and effects of AM fungi within field communities.
Given the ubiquous presence of AM fungi, a major constraint to the evaluation of the activity of AM colonisation has been the need to account for the indigenous soil native inoculum. This has to be controlled (i.e. reduced or eliminated) if we are to obtain a true control treatment for analysis of arbuscular mycorrhizas in natural substrates. There are various procedures possible for achieving such an objective, and the purpose of this chapter is to provide details of a number of techniques and present some evaluation of their advantages and disadvantages.
Although there have been a large number of experiments to investigated the effectiveness of different sterilization procedures for reducing pathogenic soil fungi, little information is available on their impact on beneficial organisms such as AM fungi. Furthermore, some of the techniques have been shown to affect physical and chemical soil characteristics as well as eliminate soil microorganisms that can interfere with the development of mycorrhizas, and this creates difficulties in the interpretation of results simply in terms of possible mycorrhizal activity.
An important subject is the differentiation of methods that involve sterilization from those focussed on indigenous inoculum reduction. Soil sterilization aims to destroy or eliminate microbial cells while maintaining the existing chemical and physical characteristics of the soil (Wolf and Skipper 1994). Consequently, it is often used for experiments focussed on specific AM fungi, or to establish a negative control in some other types of study. In contrast, the purpose of inoculum reduction techniques is to create a perturbation that will interfere with mycorrhizal formation, although not necessarily eliminating any component group within the inoculum. Such an approach allows the establishment of different degrees of mycorrhizal formation between treatments and the study of relative effects.
Frequently the basic techniques used to achieve complete sterilization or just an inoculum reduction may be similar but the desired outcome is accomplished by adjustments of the dosage or intensity of the treatment. The ultimate choice of methodology for establishing an adequate non-mycorrhizal control depends on the design of the particular experiments, the facilities available and the amount of soil requiring treatment
The role of multiple marks in epigenetic silencing and the emergence of a stable bivalent chromatin state
We introduce and analyze a minimal model of epigenetic silencing in budding
yeast, built upon known biomolecular interactions in the system. Doing so, we
identify the epigenetic marks essential for the bistability of epigenetic
states. The model explicitly incorporates two key chromatin marks, namely H4K16
acetylation and H3K79 methylation, and explores whether the presence of
multiple marks lead to a qualitatively different systems behavior. We find that
having both modifications is important for the robustness of epigenetic
silencing. Besides the silenced and transcriptionally active fate of chromatin,
our model leads to a novel state with bivalent (i.e., both active and
silencing) marks under certain perturbations (knock-out mutations, inhibition
or enhancement of enzymatic activity). The bivalent state appears under several
perturbations and is shown to result in patchy silencing. We also show that the
titration effect, owing to a limited supply of silencing proteins, can result
in counter-intuitive responses. The design principles of the silencing system
is systematically investigated and disparate experimental observations are
assessed within a single theoretical framework. Specifically, we discuss the
behavior of Sir protein recruitment, spreading and stability of silenced
regions in commonly-studied mutants (e.g., sas2, dot1) illuminating the
controversial role of Dot1 in the systems biology of yeast silencing.Comment: Supplementary Material, 14 page
Protein Content and Oil Composition of Almond from Moroccan Seedlings: Genetic Diversity, Oil Quality and Geographical Origin
The protein and oil content and the fatty acid profile of the kernels of selected almond genotypes from four different Moroccan regions were determined in order to evaluate the kernel quality of the plant material of these different regions. The ranges of oil content (48.7–64.5 % of kernel DW), oleic (61.8–80.2 % of total oil), linoleic (11.4–27.0 %), palmitic (5.6–7.7 %), stearic (1.3–3.1 %), and palmitoleic (0.4–0.9 %) acid percentages agreed with previous results of other almond genotypes, but the protein content (14.1–35.1 % of kernel DW) showed that some genotypes had higher values than any previously recorded in almond. Some genotypes from mountainous regions showed kernels with very high oil content as well as high and consistent oleic and linoleic ratio, establishing a possible differentiation according to the geographical origin. These differences may allow establishing a geographical denomination for almond products. In terms of genetic diversity, oleic and linoleic acids were confirmed to be the most variable components of almond oil chemical composition among genotypes. Additionally, the genotypes with extreme favorable values, such as high protein content, could be incorporated into an almond breeding program aiming at an increase in kernel quality.Peer ReviewedPrunus amygdalusProtein contentOil contentFatty acidsQualityGenetic resourcesBreedingPublishe
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