Correlation of omega-3 levels in serum phospholipid from 2053 human blood samples with key fatty acid ratios

<p>Abstract</p> <p>Background</p> <p>This research was conducted to explore the relationships between the levels of omega-3 fatty acids in serum phospholipid and key fatty acid ratios including potential cut-offs for risk factor assessment with respect to coronary heart disease and fatal ischemic heart disease.</p> <p>Methods</p> <p>Blood samples (n = 2053) were obtained from free-living subjects in North America and processed for determining the levels of total fatty acids in serum phospholipid as omega-3 fatty acids including EPA (eicosapentaenoic acid, 20:5 n-3) and DHA (docosahexaenoic acid, 22:6 n-3) by combined thin-layer and gas-liquid chromatographic analyses. The omega-3 levels were correlated with selected omega-6: omega-3 ratios including AA (arachidonic acid, 20:4n-6): EPA and AA:(EPA+DHA). Based on previously-published levels of omega-3 fatty acids considered to be in a 'lower risk' category for heart disease and related fatality, 'lower risk' categories for selected fatty acid ratios were estimated.</p> <p>Results</p> <p>Strong inverse correlations between the summed total of omega-3 fatty acids in serum phospholipid and all four ratios (omega-6:omega-3 (n-6:n-3), AA:EPA, AA:DHA, and AA:(EPA+DHA)) were found with the most potent correlation being with the omega-6:omega-3 ratio (R²= 0.96). The strongest inverse relation for the EPA+DHA levels in serum phospholipid was found with the omega-6: omega-3 ratio (R²= 0.94) followed closely by the AA:(EPA+DHA) ratio at R²= 0.88. It was estimated that 95% of the subjects would be in the 'lower risk' category for coronary heart disease (based on total omega-3 ≥ 7.2%) with omega-6:omega-3 ratios <4.5 and AA:(EPA+DHA) ratios <1.4. The corresponding ratio cut-offs for a 'lower risk' category for fatal ischemic heart disease (EPA+DHA ≥ 4.6%) were estimated at < 5.8 and < 2.1, respectively.</p> <p>Conclusions</p> <p>Strong inverse correlations between the levels of omega-3 fatty acids in serum (or plasma) phospholipid and omega-6: omega-3 ratios are apparent based on this large database of 2053 samples. Certain fatty acid ratios may aid in cardiovascular disease-related risk assessment if/when complete profiles are not available.</p

Development of the forSIM model to quantify positive and negative hydrological impacts of tropical reforestation

Existing approaches to modelling the impacts of reforestation on tropical hydrology only simulate one or two changes, thereby limiting our ability to quantify the balance between complex positive and negative changes, even for a single micro-basin. To initiate a more holistic and multiscale approach, we develop a new simulation model structure within the Matlab-Simulink systems environment that firstly, illustrates quantifiable interrelationships between reforestation-related hydrological changes in the component systems of evapotranspiration, runoff generation, sediment delivery and nutrient processes. Secondly, the model structure allows us to highlight basin-scale time-series observations needed to quantify reforestation-related changes in the component hydrological processes. The dynamic model developed is called forSIM and comprises of component models that are derived by means of the data-based mechanistic (DBM) philosophy. Such a modelling approach is required to constrain the large uncertainties that can arise from whole system modelling. The review of the hydrological processes and controlling characteristics that change following reforestation and, therefore, need to be simulated, has highlighted the lack of basin-scale time-series observations of the potentially positive impacts of ‘protective’ reforestation on sediment and nutrient delivery, and the need to utilise more macro-scale data. The next phase of the modelling process is to derive estimates of systems parameters and simulation scenarios for specific macro-basins in the tropics undergoing extensive reforestation

A woman's reproductive lifecycle: a developmental journey

This paper describes the development of a computer-facilitated learning package that integrates the various stages of A Woman's Reproductive Life Cycle integrating reproductive and endocrine physiology. A holistic yet modular approach has been taken with the design of the package and the modules follow the developmental journey of a woman throughout her major reproductive life stages from birth to menopause incorporating puberty, menstrual cycles, contraception and pregnancy. The overall development approaches are described as a part of the package design. Students are presented with a single case study and follow the reproductive and endocrine changes that take place in this woman over time. A core component of the package is a graphical simulation tool, which has been developed to encourage exploration and understanding of the complex mechanisms involved in hormonal regulation of the menstrual cycle

Developments in authentic learning: a woman's reproductive life cycle

This paper describes the development of a computer-facilitated learning package that integrates the various stages of A Woman's Reproductive Life Cycle integrating reproductive and endocrine physiology. The authentic learning design of the package follows the developmental journey of a woman throughout her major reproductive life stages from birth to menopause incorporating puberty, menstrual cycles, contraception and pregnancy. A core component of the package is a graphical simulation tool, which has been developed to encourage exploration and understanding of the complex mechanisms involved in hormonal regulation of the menstrual cycle which is complemented by anatomical resources of female reproductive anatomy. An initial evaluation of the menstrual cycle module was undertaken to determine future design directions. One hundred and twenty-three second year physiology students participated in the formative evaluation of the modul

The CONSERT operations planning process for the Rosetta mission

The COmet Nucleus Sounding Experiment by Radio wave Transmission (CONSERT / Rosetta) has been designed to sound the interior of the comet 67P/Churyumov-Gerasimenko. This instrument consists of two parts: one onboard Rosetta and the other one onboard Philae. A good CONSERT science measurement sequence requires joint operations of both spacecrafts in a relevant geometry. The geometric constraints to be fulfilled involve the position and the orientation of both Rosetta and Philae. At the moment of planning the post-landing and long-term science operations for Rosetta instruments, the actual comet shape and the landing location remained largely unknown. In addition, the necessity of combining operations of Rosetta spacecraft and Philae spacecraft makes the planning process for CON- SERT particularly complex. In this paper, we present the specific methods and tools we developed, in close collaboration with the mission and the science operation teams for both Rosetta and Philae, to identify, rank and plan the operations for CONSERT science measurements. The presented methods could be applied to other missions involving joint operations between two platforms, on a complex shaped object

The CONSERT operations planning process for the Rosetta mission

In the scope of European Space Agency's Rosetta mission, the COmet Nucleus Sounding Experiment by Radio wave Transmission (CONSERT) has sounded the deep interior of the nucleus of comet 67P/Churyumov-Gerasimenko. The CONSERT experiment main objective was to image the interior of the comet nucleus. This bi-static radar experiment with instrument units on-board both, the Rosetta main spacecraft and its lander Philae, requires a specific geometric configuration to operate and produce fruitful science data. Thus, these geometric constraints involve mainly the position and orientation of Rosetta and Philae. From the operations planning point of view, the mission constraints imposed observation slots to be defined far before their execution, while the comet shape, spacecraft trajectories and landing site were still unknown. The CONSERT instrument operations scheduling had to be designed jointly for Rosetta and Philae platforms, based on different time scales and planning concepts. We present the methods and tools we developed to cope with the complexity of this planning process. These operations planning concepts allowed handling the complexity of multiple platform operations and the lack of prior knowledge of the observed target