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In a forward chemical equilibrium problem (FCEP), the state of minimum Gibbs energy for a chemical system is sought, in which temperature, pressure, elemental amounts, and thermodynamic model parameters are prescribed. We herein present a mathematical framework for characterizing and solving inverse chemical equilibrium problems (ICEP), a class of problems for which one or more of those prescribed conditions in a FCEP are unknown in advance. In an ICEP, complementary conditions must be imposed, which are referred to here as equilibrium constraints. Examples of ICEPs include those in which a certain property is known at equilibrium (e.g., volume is specified instead of pressure; enthalpy is specified instead of temperature; pH is specified instead of the amount of element H). The equilibrium constraints may also be specified by equations that govern the relationship between several equilibrium properties (e.g., the equations relating temperature, pressure, density, energy, and velocity of the gases produced during the detonation of an explosive). Chemical Engineering Science, 252 ISSN:0009-2509

The fast decay in PEM fuel cells of a highly active, high performance, but unstable Fe/N/C catalyst like our NC_Ar + NH3 follows a chemical, not an electrochemical, demetallation mechanism for its ORR active FeN4 sites in the catalyst micropores.

Although soils provide social and ecological services which are of a clearly transnational dimension, the management of soils needs to be addressed locally. Thus, an appropriate - or better, effective governance for sustainable soil management at national level is essential. This chapter provides some fundamental recommendations for an effective governance based on legal studies from several African countries, namely Cameroon, Kenya and Zambia.

In theoretical ecology, recent field experiments on terrestrial vertebrates observe that the predator-prey interaction can not only be curtailed by direct consumption but also governed by some indirect effects such as the fear of predator which may reduce the reproduction rate of prey individuals. Based on this fact, we have developed and explored the predator-prey interaction with the influence of both cost and benefit of fear effect (felt by prey). A Holling type III functional response with the effect of habitat complexity has been taken to consume the prey biomass. Positivity and boundedness of the studied system prove that the model is well-behaved. The uniform persistence of the studied system is derived analytically under some parametric restrictions. The feasibility conditions and stability criteria of each equilibrium points have been discussed. Next, we have exhibited the existence of Hopf-bifurcation around the interior equilibrium point. Our mathematical analyses show that habitat complexity and fear effect both have a great impact on the persistence of the predator biomass. Furthermore, we have investigated the effect of breeding delay parameter such that the system loses its stability behaviour and enters into a limit cycle oscillations through Hopf-bifurcation. Numerical simulations are illustrated to verify our analytical outcomes. Numerically, we have perturbed the death rates of prey and predator species with Gaussian white noise terms due to the effects of environmental fluctuations.

Ethnopharmacological relevance Phaseaoli pericarpium (bean pods) is a pharmacopeial plant material traditionally used as a diuretic and antidiabetic agents. Diuretic activity of pod extracts was reported first in 1608. Since then Phaseoli pericarpium tea figures in many textbooks as medicinal plant material used by patients. Aim of the study Despite the traditional use of extracts from Phaseolium vulgaris pericarp, limited information is available on bioactivity, chemical composition, and bioavailability of such preparations. The following study aimed to investigate the phytochemical composition, the in vitro permeability of selected extract's constituents over the Caco-2 permeation system, and potential antivirulence activity against uropathogenic Escherichia coli of a hydroalcoholic Phaseoli pericarpium extract (PPX) in vitro to support its traditional use as a remedy used in urinary tract infections. Material and methods The chemical composition of the extract PPX [ethanol:water 7:3 (v/v)] investigated by using UHPLC-DAD-MSn and subsequent dereplication. The permeability of compounds present in PPX was evaluated using the Caco-2 monolayer permeation system. The influence of PPX on uropathogenic E. coli (UPEC) strain NU14 proliferation and against the bacterial adhesion to T24 epithelial cells was determined by turbidimetric assay and flow cytometry, respectively. The influence of the extract on the mitochondrial activity of T24 host cells was monitored by MTT assay. Results LC-MSn investigation and dereplication, indicated PPX extract to be dominated by a variety of flavonoids, with rutin as a major compound, and soyasaponin derivatives. Rutin, selected soyasaponins and fatty acids were shown to permeate the Caco-2 monolayer system, indicating potential bioavailability following oral intake. The extract did not influence the viability of T24 cells after 1.5h incubation at 2 mg/mL and UPEC. PPX significantly reduced the bacterial adhesion of UPEC to human bladder cells in a concentration-dependent manner (0.5–2 mg/mL). Detailed investigations by different incubation protocols indicated that PPX seems to interact with T24 cells, which subsequently leads to reduced recognition and adhesion of UPEC to the host cell membrane. Conclusions PPX is characterised by the presence of flavonoids (e.g. rutin) and saponins, from which selected compounds might be bioavailable after oral application, as indicated by the Caco-2 permeation experiments. Rutin and some saponins can be considered as potentially bioavailable after the oral intake. The concentration-dependent inhibition of bacterial adhesion of UPEC to T24 cells justifies the traditional use of Phaseoli pericarpium in the prevention and treatment of urinary tract infections.

We present a protocol for the biosensor Cell-Fit-HD4D. It enables long-term monitoring and correlation of single-cell fate with subcellular-deposited energy of ionizing radiation. Cell fate tracking using widefield time-lapse microscopy is uncoupled in time from confocal ion track imaging. Registration of both image acquisition steps allows precise ion track assignment to cells and correlation with cellular readouts. For complete details on the use and execution of this protocol, please refer to Niklas et al. (2022).

What present-day foragers do for their living and what they eat have long been privileged areas for exploring human behavior, global health, and human evolution. While many studies have focused on hunting and meat acquisition, less attention has been given to gathering and plant foods. Despite evidence of variation in both nutritional quality and energetic costs of gathering different plants, the overall effort spent on gathering in relation to other subsistence tasks is still under explored. In the current context of economic, climate, and social changes, many forager societies also rely on other subsistence strategies, including agriculture and wage labor. In this study, we aim to explore the place of gathering in the livelihood of a mixed economy society, the Baka forager-horticulturalists of southeastern Cameroon, by comparing the involvement and the costs of activities related to food acquisition. From a pool of 153 adult participants (97 women and 56 men), we collected 246 daily records using a GPS (Global Positioning System) tracker combined with heart rate monitor and time allocation recalls. We compared the duration, distance traveled, and the intensity of work, measured by calculating the metabolic equivalent of task (MET), of subsistence activities related to food acquisition. Results from this work show that gathering activities, performed by both women and men, are energetically costly, with higher MET values than hunting and fishing activities. Furthermore, the MET values vary depending on the targeted plant foods. We discuss these insights in the overall framework of subsistence patterns, merging them with the socio-cultural and environmental factors that might explain Baka livelihood and subsistence strategy.

AbstractIndirect climate effects on tree fecundity that come through variation in size and growth (climate-condition interactions) are not currently part of models used to predict future forests. Trends in species abundances predicted from meta-analyses and species distribution models will be misleading if they depend on the conditions of individuals. Here we find from a synthesis of tree species in North America that climate-condition interactions dominate responses through two pathways, i) effects of growth that depend on climate, and ii) effects of climate that depend on tree size. Because tree fecundity first increases and then declines with size, climate change that stimulates growth promotes a shift of small trees to more fecund sizes, but the opposite can be true for large sizes. Change the depresses growth also affects fecundity. We find a biogeographic divide, with these interactions reducing fecundity in the West and increasing it in the East. Continental-scale responses of these forests are thus driven largely by indirect effects, recommending management for climate change that considers multiple demographic rates.