Mega-trends in the Southern African region

This study aims to describe recent developments in the Southern African region by documenting a set of mega-trends defining social, economic, political and environmental conditions. It includes analysis of the recent past as well as projections of future trends. To the extent possible, the report is based on information from 2010 to the present, except in some cases where more recent information was not available. The purpose of this analysis is to get a snapshot of current conditions in the Southern African region and the dynamics that generated them, to inform the design and implementation of investments to secure climate-resilient agricultural livelihoods in the region. The study goes beyond simply tracing trends, however, and provides guidance on how the information can best be used in making plans for the future. The mega-trend analysis gives insights into forces that will shape the future but does not provide predictions of the future. Humans are typically very linear thinkers and tend to look at trends from the past and project them forwards into the future, and we often fall into the trap of thinking that the future is defined by what has happened in the past. There is considerable uncertainty over how several of these mega-trends will play out in the near future, with the possibility of major disruptions and changes on the horizon. This can be seen quite clearly in the impact of the COVID-19 pandemic which is still unfolding, and which is already disrupting expectations of future conditions. This uncertainty of future conditions greatly complicates decision-making today. To address this complication, the development of scenarios to identify a range of plausible futures is an important tool for decision-makers. In the final section of the report we give examples of recent scenario work in the region to illustrate how the analysis of megatrends and their uncertainties can be useful in strategic decision-making under uncertainty

Energy Value of Wet Distillers Grains in High Forage Diets

One hundred sixty crossbred steers were used to determine the energy value of wet distillers grains in high forage diets. By design, steers had similar intakes and gains across treatments. Diets included either wet distillers grains (WDGS) or dry rolled corn, sorghum silage, grass hay and supplement (DRC). Diets were formulated to meet degradable intake protein and metabolizable protein requirements. The energy value of wet distillers grains was calculated using the National Research Council model (1996). In this study, wet distillers grains contained 130% of the energy of dry rolled corn when fed in forage-based diets

Water Use in the Eagle Ford Shale: An Economic and Policy Analysis of Water Supply and Demand

The Eagle Ford Shale is a massive geologic formation located in South Texas spanning 30 Texas counties from Brazos County in the north east to Webb County in the southwest . With the advent of hydraulic fracturing (HF) and horizontal drilling, over 200 operators have been able to tap into previously inaccessible shale reserves to p roduce abundant amounts of oil and gas. The oil and gas proliferation in the Eagle Ford has seen exponential growth , and production is not anticipated to decline until 2025. In addition, a typical HF well in the Eagle Ford is estimated to consume about 13 acre - feet of water for a standard 5000 foot lateral . Approximately 90% of water for HF comes from fresh groundwater aquifers. This interaction of HF and water consumption is of primary importance from a poli tical and economic perspective. This s erves as t he focal point of our report. Using the tools of statistics, our research considered the groundwater consumption trends within the Eagle Ford counties using water consumption data of municipal, irrigation, mining (oil and gas) and other categories over a span of four years . This analysis showed that fresh groundwater is being consumed at about 2.5 times the groundwater recharge rates . Furthermore, irrigation is using more water than all other water - consuming categories combined. Thus, the water problem reaches well beyond the use of fresh grou ndwater for mining . With respect to likely requirements of water for HF, we posited this question: “ W ill technology bail us out?” Retrofitting learning curves to our data for water uses and the length of the well la teral , we find that after i nitial improvements in water us age, the technology appears to have stabilized. This, coupled with massi ve irrigation water consumption suggests that technology will not be a major source of water savings in the long run. Instead, we must look to better public policies . From a policy perspective, the status quo for groundwater u se is governed by the Rule of Capture and the oversight of groundwater conservation districts (GCDs) . T here exists a real conflict as large - scale water users are competing for a diminishing aquifer resource with no market signals of increasing scarcity. In addition, groundwater wells drilled in connection with oil and gas exploration are exempt from GCD per mitting requirements and receive a de facto “free pass” to water for HF. Likewise, limita tions imposed on irrigation users by the GCDs are rarely binding, so these users usually get a free pass as well. Our analysis leads us to three basic policy recommend ations . The first involves mandatory reporting of all groundwater uses by all classes of water use r s. Currently, government agencies and the public lack basic information on actual water consumption; t his policy seeks to relax that knowledge gap and bring transparency. Second , we propose incentivizing oil and gas companies to substitute brackish groundwater for fresh ground water. Our proposal calls for a severance tax reduction for tho se companies limiting fresh groundwater use for HF in the Eagle Ford. In addition to a temporary reduction in the severance tax, these companies c ould be recognized by the RRC and possibly the TCEQ for their environmental stewardship with a “ Green Star ” designation. Our t hird , most heterodox and long - term recommendation is to define ground water property rights on a per - acre ownership basis, which would attach to the surface owner’s real property. Under this system, the owner s of the water rights would be able to sell their water as they would any other resource, and the market would adjust the price of water to an economically efficient level. Most importantly, it would remove the incentive to use all you can today , leaving more water for the future at a lower future price.Commissioner Christi Craddick, Texas Railroad Commissio

Up-regulation of METCAM/MUC18 promotes motility, invasion, and tumorigenesis of human breast cancer cells

<p>Abstract</p> <p>Background</p> <p>Conflicting research has identified METCAM/MUC18, an integral membrane cell adhesion molecule (CAM) in the Ig-like gene super-family, as both a tumor promoter and a tumor suppressor in the development of breast cancer. To resolve this, we have re-investigated the role of this CAM in the progression of human breast cancer cells.</p> <p>Methods</p> <p>Three breast cancer cell lines were used for the tests: one luminal-like breast cancer cell line, MCF7, which did not express any METCAM/MUC18, and two basal-like breast cancer cell lines, MDA-MB-231 and MDA-MB-468, which expressed moderate levels of the protein.</p> <p>MCF7 cells were transfected with the human METCAM/MUC18 cDNA to obtain G418-resistant clones which expressed the protein and were used for testing effects of human METCAM/MUC18 expression on <it>in vitro </it>motility and invasiveness, and <it>in vitro </it>and <it>in vivo </it>tumorigenesis. Both MDA-MB-231 and MDA-MB-468 cells already expressed METCAM/MUC18. They were directly used for <it>in vitro </it>tests in the presence and absence of an anti-METCAM/MUC18 antibody.</p> <p>Results</p> <p>In MCF7 cells, enforced METCAM/MUC18 expression increased <it>in vitro </it>motility, invasiveness, anchorage-independent colony formation (<it>in vitro </it>tumorigenesis), and <it>in vivo </it>tumorigenesis. In both MDA-MB-231 and MDA-MB-468 cells, the anti-METCAM/MUC18 antibody inhibited both motility and invasiveness. Though both MDA-MB-231 and MDA-MB-468 cells established a disorganized growth in 3D basement membrane culture assay, the introduction of the anti-METCAM/MUC18 antibody completely destroyed their growth in the 3D culture.</p> <p>Conclusion</p> <p>These findings support the notion that human METCAM/MUC18 expression promotes the progression of human breast cancer cells by increasing their motility, invasiveness and tumorigenesis.</p

A Family of Chemoreceptors in Tribolium castaneum (Tenebrionidae: Coleoptera)

Chemoperception in invertebrates is mediated by a family of G-protein-coupled receptors (GPCR). To date nothing is known about the molecular mechanisms of chemoperception in coleopteran species. Recently the genome of Tribolium castaneum was sequenced for use as a model species for the Coleoptera. Using blast searches analyses of the T. castaneum genome with previously predicted amino acid sequences of insect chemoreceptor genes, a putative chemoreceptor family consisting of 62 gustatory receptors (Grs) and 26 olfactory receptors (Ors) was identified. The receptors have seven transmembrane domains (7TMs) and all belong to the GPCR receptor family. The expression of the T. castaneum chemoreceptor genes was investigated using quantification real- time RT-PCR and in situ whole mount RT-PCR analysis in the antennae, mouth parts, and prolegs of the adults and larvae. All of the predicted TcasGrs were expressed in the labium, maxillae, and prolegs of the adults but TcasGr13, 19, 28, 47, 62, 98, and 61 were not expressed in the prolegs. The TcasOrs were localized only in the antennae and not in any of the beetles gustatory organs with one exception; the TcasOr16 (like DmelOr83b), which was localized in the antennae, labium, and prolegs of the beetles. A group of six TcasGrs that presents a lineage with the sugar receptors subfamily in Drosophila melanogaster were localized in the lacinia of the Tribolium larvae. TcasGr1, 3, and 39, presented an ortholog to CO2 receptors in D. melanogaster and Anopheles gambiae was recorded. Low expression of almost all of the predicted chemoreceptor genes was observed in the head tissues that contain the brains and suboesophageal ganglion (SOG). These findings demonstrate the identification of a chemoreceptor family in Tribolium, which is evolutionarily related to other insect species

Amino Acid Residues Contributing to Function of the Heteromeric Insect Olfactory Receptor Complex

Olfactory receptors (Ors) convert chemical signals—the binding of odors and pheromones—to electrical signals through the depolarization of olfactory sensory neurons. Vertebrates Ors are G-protein-coupled receptors, stimulated by odors to produce intracellular second messengers that gate ion channels. Insect Ors are a heteromultimeric complex of unknown stoichiometry of two seven transmembrane domain proteins with no sequence similarity to and the opposite membrane topology of G-protein-coupled receptors. The functional insect Or comprises an odor- or pheromone-specific Or subunit and the Orco co-receptor, which is highly conserved in all insect species. The insect Or-Orco complex has been proposed to function as a novel type of ligand-gated nonselective cation channel possibly modulated by G-proteins. However, the Or-Orco proteins lack homology to any known family of ion channel and lack known functional domains. Therefore, the mechanisms by which odors activate the Or-Orco complex and how ions permeate this complex remain unknown. To begin to address the relationship between Or-Orco structure and function, we performed site-directed mutagenesis of all 83 conserved Glu, Asp, or Tyr residues in the silkmoth BmOr-1-Orco pheromone receptor complex and measured functional properties of mutant channels expressed in Xenopus oocytes. 13 of 83 mutations in BmOr-1 and BmOrco altered the reversal potential and rectification index of the BmOr-1-Orco complex. Three of the 13 amino acids (D299 and E356 in BmOr-1 and Y464 in BmOrco) altered both current-voltage relationships and K+ selectivity. We introduced the homologous Orco Y464 residue into Drosophila Orco in vivo, and observed variable effects on spontaneous and evoked action potentials in olfactory neurons that depended on the particular Or-Orco complex examined. Our results provide evidence that a subset of conserved Glu, Asp and Tyr residues in both subunits are essential for channel activity of the heteromeric insect Or-Orco complex

Atypical Membrane Topology and Heteromeric Function of Drosophila Odorant Receptors In Vivo

Drosophila olfactory sensory neurons (OSNs) each express two odorant receptors (ORs): a divergent member of the OR family and the highly conserved, broadly expressed receptor OR83b. OR83b is essential for olfaction in vivo and enhances OR function in vitro, but the molecular mechanism by which it acts is unknown. Here we demonstrate that OR83b heterodimerizes with conventional ORs early in the endomembrane system in OSNs, couples these complexes to the conserved ciliary trafficking pathway, and is essential to maintain the OR/OR83b complex within the sensory cilia, where odor signal transduction occurs. The OR/OR83b complex is necessary and sufficient to promote functional reconstitution of odor-evoked signaling in sensory neurons that normally respond only to carbon dioxide. Unexpectedly, unlike all known vertebrate and nematode chemosensory receptors, we find that Drosophila ORs and OR83b adopt a novel membrane topology with their N-termini and the most conserved loops in the cytoplasm. These loops mediate direct association of ORs with OR83b. Our results reveal that OR83b is a universal and integral part of the functional OR in Drosophila. This atypical heteromeric and topological design appears to be an insect-specific solution for odor recognition, making the OR/OR83b complex an attractive target for the development of highly selective insect repellents to disrupt olfactory-mediated host-seeking behaviors of insect disease vectors