A Catalogue of the Poisonous Plants of Iowa

For a number of years we have given a course of lectures on plants poisonous and injurious to live stock to the veterinary students of the Iowa State College. From stockmen and farmers in various parts of the state we frequently receive queries in regard to poisonous plants. In some cases the queries are accompanied with specimens. We are often asked to give more detailed information. In many cases, however, the evidence of poisoning is not proven; certain weeds are found in a pasture and the farmer supposes that they may be responsible for the death of animals

Some Railroad Water Supplies

Complaints are frequently made with reference to railroad water supplies. These complaints come from passengers as well as stockmen who are compelled to use the water for their stock

The Underground Organs of a Few Weeds

A study of some of the troublesome perennial weeds and their methods of extermination has led the authors to look up the botanical descriptions of the underground portions and manner of propagation

Isotopic and genetic methods reveal the role of the gut microbiome in mammalian host essential amino acid metabolism.

Intestinal microbiota perform many functions for their host, but among the most important is their role in metabolism, especially the conversion of recalcitrant biomass that the host is unable to digest into bioavailable compounds. Most studies have focused on the assistance gut microbiota provide in the metabolism of carbohydrates, however, their role in host amino acid metabolism is poorly understood. We conducted an experiment on Mus musculus using 16S rRNA gene sequencing and carbon isotope analysis of essential amino acids (AAESS) to quantify the community composition of gut microbiota and the contribution of carbohydrate carbon used by the gut microbiome to synthesize AAESS that are assimilated by mice to build skeletal muscle tissue. The relative abundances of Firmicutes and Bacteroidetes inversely varied as a function of dietary macromolecular content, with Firmicutes dominating when mice were fed low-protein diets that contained the highest proportions of simple carbohydrates (sucrose). Mixing models estimated that the microbial contribution of AAESS to mouse muscle varied from less than 5% (threonine, lysine, and phenylalanine) to approximately 60% (valine) across diet treatments, with the Firmicute-dominated microbiome associated with the greatest contribution. Our results show that intestinal microbes can provide a significant source of the AAESS their host uses to synthesize structural tissues. The role that gut microbiota play in the amino acid metabolism of animals that consume protein-deficient diets is likely a significant but under-recognized aspect of foraging ecology and physiology

Pigment production and isotopic fractionations in continuous culture: okenone producing purple sulfur bacteria Part II

Okenone is a carotenoid pigment unique to certain members of Chromatiaceae, the dominant family of purple sulfur bacteria (PSB) found in euxinic photic zones. Diagenetic alteration of okenone produces okenane, the only recognized molecular fossil unique to PSB. The in vivo concentrations of okenone and bacteriochlorophyll a (Bchl a) on a per cell basis were monitored and quantified as a function of light intensity in continuous cultures of the purple sulfur bacterium Marichromatium purpuratum (Mpurp1591). We show that okenone-producing PSB have constant bacteriochlorophyll to carotenoid ratios in light-harvesting antenna complexes. The in vivo concentrations of Bchl a, 0.151 ± 0.012 fmol cell^(−1), and okenone, 0.103 ± 0.012 fmol cell^(−1), were not dependent on average light intensity (10–225 Lux) at both steady and non-steady states. This observation revealed that in autotrophic continuous cultures of Mpurp1591, there was a constant ratio for okenone to Bchl a of 1:1.5. Okenone was therefore constitutively produced in planktonic cultures of PSB, regardless of light intensity. This confirms the legitimacy of okenone as a signature for autotrophic planktonic PSB and by extrapolation water column euxinia. We measured the δ^(13)C, δ^(15)N, and δ^(34)S bulk biomass values from cells collected daily and determined the isotopic fractionations of Mpurp1591. There was no statistical relationship in the bulk isotope measurements or stable isotope fractionations to light intensity or cell density under steady and non-steady-state conditions. The carbon isotope fractionation between okenone and Bchl a with respect to overall bulk biomass (^(13)ε_pigment – biomass) was 2.2 ± 0.4‰ and −4.1 ± 0.9‰, respectively. The carbon isotopic fractionation (^(13)ε_pigment-CO_2) for the production of pigments in PSB is more variable than previously thought with our reported values for okenone at −15.5 ± 1.2‰ and −21.8 ± 1.7‰ for Bchl a

THE IMPLEMENTATION OF CONSENSUAL REGULATORY MECHANISM FOR ACTIVITIES OF FOREIGN DIRECT INVESTORS IN AFRICA

The article covers the issues of institutional changes in the African mechanism for attraction of foreign direct investments (FDI). African nations are trying to attract FDI in greater volume and to assure that such capital serves the purposes of economic development, including creation of jobs, reduction of poverty and mobilization of local capital and other factors of production. As the results of the research state, that it is productive for foreign enterprises, including Russian entities, to apply consensual approach in epistemology studies of African investments codes. Such methodology can concurrently assure the profitability of business and improvements of economic situation in host African economies

DEVELOPING THE INSTITUTIONAL FRAMEWORK OF SOUTH AFRICA AND THE NEIGHBORING STATES FOR THE PURPOSE OF ATTRACTING FOREIGN DIRECT INVESTMENTS

South Africa needs to reconsider its investment policy in order to change the current state of foreign direct investments (FDI) inflows. It is also necessary to coordinate national and international measures to assure balanced economic growth. Of particular significance also are initiatives to set up information networks that can provide foreign entrepreneurs with contemporary information on the current and promising investment projects in Africa. State bodies of South Africa need to promote the FDI inflows and offer stimuli for maintaining the high rate of sustainable economic development

The Effectiveness of Web-Based Interventions to Promote Health Behaviour Change in Adolescents: A Systematic Review

Although web-based interventions are attractive to researchers and users, the evidence about their effectiveness in the promotion of health behaviour change is still limited. Our aim was to review the effectiveness of web-based interventions used in health behavioural change in adolescents regarding physical activity, eating habits, tobacco and alcohol use, sexual behaviour, and quality of sleep. Studies published from 2016 till the search was run (May-to-June 2021) were included if they were experimental or quasi-experimental studies, pre-post-test studies, clinical trials, or randomized controlled trials evaluating the effectiveness of web-based intervention in promoting behaviour change in adolescents regarding those health behaviours. The risk of bias assessment was performed by using the Effective Public Health Practice Project (EPHPP)-Quality Assessment Tool for Quantitative Studies. Fourteen studies were included. Most were in a school setting, non-probabilistic and relatively small samples. All had a short length of follow-up and were theory driven. Thirteen showed significant positive findings to support web-based interventions' effectiveness in promoting health behaviour change among adolescents but were classified as low evidence quality. Although this review shows that web-based interventions may contribute to health behaviour change among adolescents, these findings rely on low-quality evidence, so it is urgent to test these interventions in larger controlled trials with long-term maintenance

Ecologically and geologically relevant isotope signatures of C, N, and S: okenone producing purple sulfur bacteria part I

Purple sulfur bacteria (PSB) are known to couple the carbon, nitrogen, and sulfur cycling in euxinic environments. This is the first study with multiple strains and species of okenone-producing PSB to examine the carbon (C), nitrogen (N), and sulfur (S) metabolisms and isotopic signatures in controlled laboratory conditions, investigating what isotopic fractionations might be recorded in modern environments and the geologic record. PSB play an integral role in the ecology of euxinic environments and produce the unique molecular fossil okenane, derived from the diagenetic alteration of the carotenoid pigment okenone. Cultures of Marichromatium purpuratum 1591 (Mpurp1591) were observed to have carbon isotope fractionations (13_ε_biomass – CO_2), via RuBisCO, ranging from −16.1 to −23.2‰ during exponential and stationary phases of growth. Cultures of Thiocapsa marina 5653 (Tmar5653) and Mpurp1591 had a nitrogen isotope fractionation (15_ε_biomass – NH4) of −15‰, via glutamate dehydrogenase, measured and recorded for the first time in PSB. The δ^(34)S_VCDT values and amount of stored elemental sulfur for Mpurp1591 cells grown autotrophically and photoheterotrophically were dependent upon their carbon metabolic pathways. We show that PSB may contribute to the isotopic enrichments observed in modern and ancient anoxic basins. In a photoheterotrophic culture of Mpurp1591 that switched to autotrophy once the organic substrate was consumed, there were bulk biomass δ13C values that span a broader range than recorded across the Late Devonian, Permian–Triassic, Triassic–Jurassic, and OAE2 mass extinction boundaries. This finding stresses the complexities in interpreting and assigning δ13C values to bulk organic matter preserved in the geologic record