Handling of Uncertainty in Life Cycle Inventory by Correlated Multivariate Lognormal Distributions: Application to the Design of Supply Chain Networks

In this work, we analyze the effect of incorporating life cycle inventory (LCI) uncertainty on the multi-objective optimization of chemical supply chains (SC) considering simultaneously their economic and environmental performance. To this end, we present a stochastic multi-scenario mixed-integer linear programming (MILP) coupled with a two-step transformation scenario generation algorithm with the unique feature of providing scenarios where the LCI random variables are correlated and each one of them has the desired lognormal marginal distribution. The environmental performance is quantified following life cycle assessment (LCA) principles, which are represented in the model formulation through standard algebraic equations. The capabilities of our approach are illustrated through a case study of a petrochemical supply chain. We show that the stochastic solution improves the economic performance of the SC in comparison with the deterministic one at any level of the environmental impact, and moreover the correlation among environmental burdens provides more realistic scenarios for the decision making process.

The Plasmodium serine-type SERA proteases display distinct expression patterns and non-essential in vivo roles during life cycle progression of the malaria parasite

Parasite proteases play key roles in several fundamental steps of the Plasmodium life cycle, including haemoglobin degradation, host cell invasion and parasite egress. Plasmodium exit from infected host cells appears to be mediated by a class of papain-like cysteine proteases called 'serine repeat antigens' (SERAs). A SERA subfamily, represented by Plasmodium falciparum SERA5, contains an atypical active site serine residue instead of a catalytic cysteine. Members of this SERAser subfamily are abundantly expressed in asexual blood stages, rendering them attractive drug and vaccine targets. In this study, we show by antibody localization and in vivo fluorescent tagging with the red fluorescent protein mCherry that the two P. berghei serine-type family members, PbSERA1 and PbSERA2, display differential expression towards the final stages of merozoite formation. Via targeted gene replacement, we generated single and double gene knockouts of the P. berghei SERAser genes. These loss-of-function lines progressed normally through the parasite life cycle, suggesting a specialized, non-vital role for serine-type SERAs in vivo. Parasites lacking PbSERAser showed increased expression of the cysteine-type PbSERA3. Compensatory mechanisms between distinct SERA subfamilies may thus explain the absence of phenotypical defect in SERAser disruptants, and challenge the suitability to develop potent antimalarial drugs based on specific inhibitors of Plasmodium serine-type SERAs.

A topical outline for the teaching of family health : a life-cycle approach (nursing and midwifery) /

"Project no. AID-PHA/CM/C-73-33"--T.p. verso.

Life-cycle cost analysis for utility combinations handbook : departmental staff and program participants.

"December 1985."

Software support system for data acquisition and analysis. Final report.

National Highway Traffic Safety Administration, East Liberty, Ohio

Executive summary : 1983 DOD Standardization Conference : reducing acquisition and support costs for the DOD.

Cover title.

Life-cycle costing manual for the Federal Energy Management Program : a guide for evaluating the cost effectiveness of energy conservation and renewable energy projects for new and existing federally owned and leased buildings and facilities /

"Issued originally December 1980 ; revised May 1982 ; revised November 1987."

The life cycle and epizootiology of the rabbit trematode, Hasstilesia tricolor (Stiles and Hassall, 1894) Hall, 1916. (Trematoda: Brachylaemidae).

Thesis (Ph.D.)--Cornell Univ., June 1954.

The origin of the pelagobenthic metazoan life cycle: what's sex got to do with it?

The biphasic (pelagobenthic) life cycle is found throughout the animal kingdom, and includes gametogenesis, embryogenesis, and metamorphosis. From a tangled web of hypotheses on the origin and evolution of the metazoan pelagobenthic life cycle, current opinion appears to favor a simple, larval-like holopelagic ancestor that independently settled multiple times to incorporate a benthic phase into the life cycle. This hypothesis derives originally from Haeckel's (1874) Gastraea theory of ontogeny recapitulating phylogeny, in which the gastrula is viewed as the recapitulation of a gastracan ancestor that evolved via selection on a simple, planktonic hollow ball of cells to develop the capacity to feed. Here, we propose an equally plausible hypothesis that the origin of the metazoan pelagobenthic life cycle was a direct consequence of sexual reproduction in a likely holobenthic ancestor. In doing so, we take into account new insights from poriferan development and from molecular phylogenies. In this scenario, the gastrula does not represent a recapitulation, but simply an embryological stage that is an outcome of sexual reproduction. The embryo can itself be considered as the precursor to a biphasic lifestyle, with the embryo representing one phase and the adult another phase. This hypothesis is more parsimonious because it precludes the need for multiple, independent origins of the benthic form. It is then reasonable to consider that multilayered, ciliated embryos ultimately released into the water column are subject to natural selection for dispersal/longevity/feeding that sets them on the evolutionary trajectory towards the crown metazoan planktonic larvae. These new insights from poriferan development thus clearly support the intercalation hypothesis of bilaterian larval evolution, which we now believe should be extended to discussions of the origin of biphasy in the metazoan last common ancestor.

Geographical variation in carbon dioxide fluxes from soils in agro-ecosystems and its implications for life-cycle assessment

1. Exchange of carbon dioxide (CO2) from soils can contribute significantly to the global warming potential (GWP) of agro-ecosystems. Due to variations in soil type, climatic onditions and land management practices, exchange of CO2 can differ markedly in different geographical locations. The food industry is developing carbon footprints for their products necessitating integration of CO2 exchange from soils with other CO2 emissions along the food chain. It may be advantageous to grow certain crops in different geographical locations to minimize CO2 emissions from the soil, and this may provide potential to offset other emissions in the food chain, such as transport. 2. Values are derived for the C balance of soils growing horticultural crops in the UK, Spain and Uganda. Net ecosystem production (NEP) is firstly calculated from the difference in net primary production (NPP) and heterotrophic soil respiration (Rh). Both NPP and Rh were estimated from intensive direct field measurements. Secondly, net biome production (NBP) is calculated by subtracting the crop biomass from NEP to give an indication of C balance. The importance of soil exchange is discussed in the light of recent discussions on carbon footprints and within the context of food life-cycle assessment (LCA). 3. The amount of crop relative to the biomass and the Rh prevailing in the different countries were the dominant factors influencing the magnitude of NEP and NBP. The majority of the biomass for lettuce Lactuca sativa and vining peas Pisum sativum, was removed from the field as crop; therefore, NEP and NBP were mainly negative. This was amplified for lettuces grown in Uganda (-16·5 and -17 t C ha-1 year-1 compared to UK and Spain -4·8 to 7·4 and -5·1 to 6·3 t C ha-1 year-1 for NEP and NBP, respectively) where the climate elevated Rh. 4. Synthesis and applications. This study demonstrates the importance of soil emissions in the overall life cycle of vegetables. Variability in such emissions suggests that assigning a single value to food carbon footprints may not be adequate, even within a country. Locations with high heterotrophic soil respiration, such as Spain and Uganda (21·9 and 21·6 t C ha-1 year-1, respectively), could mitigate the negative effects of climate on the C costs of crop production by growth of crops with greater returns of residue to the soil. This would minimize net CO2 emissions from these agricultural ecosystems.

Life cycle of Deccan trap magma chambers: A crystal scale elemental and strontium isotopic investigation

The Deccan Trap basalts are the remnants of a massive series of lava flows that erupted at the K/T boundary and covered 1-2 million km2 of west-central India. This eruptive event is of global interest because of its possible link to the major mass extinction event, and there is much debate about the duration of this massive volcanic event. In contrast to isotopic or paleomagnetic dating methods, I explore an alternative approach to determine the lifecycle of the magma chambers that supplied the lavas, and extend the concept to obtain a tighter constraint on Deccan’s duration. My method relies on extracting time information from elemental and isotopic diffusion across zone boundaries in individual crystals. I determined elemental and Sr-isotopic variations across abnormally large (2-5 cm) plagioclase crystals from the Thalghat and Kashele “Giant Plagioclase Basalts” from the lowermost Jawhar and Igatpuri Formations respectively in the thickest Western Ghats section near Mumbai. I also obtained bulk rock major, trace and rare earth element chemistry of each lava flow from the two formations. Thalghat flows contain only 12% zoned crystals, with 87 Sr/86Sr ratios of 0.7096 in the core and 0.7106 in the rim, separated by a sharp boundary. In contrast, all Kashele crystals have a wider range of 87Sr/86Sr values, with multiple zones. Geochemical modeling of the data suggests that the two types of crystals grew in distinct magmatic environments. Modeling intracrystalline diffusive equilibration between the core and rim of Thalghat crystals led me to obtain a crystal growth rate of 2.03x10-10 cm/s and a residence time of 780 years for the crystals in the magma chamber(s). Employing some assumptions based on field and geochronologic evidence, I extrapolated this residence time to the entire Western Ghats and obtained an estimate of 25,000–35,000 years for the duration of Western Ghats volcanism. This gave an eruptive rate of 30–40 km3/yr, which is much higher than any presently erupting volcano. This result will remain speculative until a similarly detailed analytical-modeling study is performed for the rest of the Western Ghats formations.