Bat species richness and community composition along a mega-transect in the Okavango river basin:
- Authors: Weier, Sina M , Keith, Mark , Neef, Götz G , Parker, Daniel M , Taylor, Peter
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149264 , vital:38820 , https://doi.org/10.3390/d12050188
- Description: The Okavango River Basin is a hotspot of bat diversity that requires urgent and adequate protection. To advise future conservation strategies, we investigated the relative importance of a range of potential environmental drivers of bat species richness and functional community composition in the Okavango River Basin. During annual canoe transects along the major rivers, originating in the central Angolan highlands, we recorded more than 25,000 bat echolocation calls from 2015 to 2018. We corrected for possible biases in sampling design and effort.
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- Date Issued: 2020
Biocompatibility of biomaterials for nanoencapsulation: Current approaches
- Authors: Witika, Bwalya A , Makoni, Pedzisai A , Matafwali, Scott K , Chabalenge, Billy , Mwila, Chiluba , Kalungia, Aubrey C , Nkanga, Christian I , Bapolisi, Alain M , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183289 , vital:43939 , xlink:href="https://doi.org/10.3390/nano10091649"
- Description: Nanoencapsulation is an approach to circumvent shortcomings such as reduced bioavailability, undesirable side effects, frequent dosing and unpleasant organoleptic properties of conventional drug delivery systems. The process of nanoencapsulation involves the use of biomaterials such as surfactants and/or polymers, often in combination with charge inducers and/or ligands for targeting. The biomaterials selected for nanoencapsulation processes must be as biocompatible as possible. The type(s) of biomaterials used for different nanoencapsulation approaches are highlighted and their use and applicability with regard to haemo- and, histocompatibility, cytotoxicity, genotoxicity and carcinogenesis are discussed.
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- Date Issued: 2020
Bioelectrocatalysis and surface analysis of gold coated with nickel oxide/hydroxide and glucose oxidase towards detection of glucose:
- Authors: Njoko, Nqobile , Louzada, Marcel , Britton, Jonathan , Khene, Samson M , Nyokong, Tebello , Mashazi, Philani N
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150071 , vital:38937 , https://doi.org/10.1016/j.colsurfb.2020.110981
- Description: The fabricating of metal oxide thin films onto conducting surfaces continues to grow and their potential applications as surfaces for biosensor applications is of paramount importance. The correct orientation of glucose oxidase redox enzymes yields very important biointerfaces capable of selectively detecting D-glucose as a measure of blood sugar for healthy and diabetic sick patients. The electrodeposition of redox enzymes, such as glucose oxidase enzymes, onto gold electrode surfaces pre-modified with nickel oxide was investigated in this work.
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- Date Issued: 2020
Biological control of water lettuce, Pistia stratiotes L., facilitates macroinvertebrate biodiversity recovery: a mesocosm study
- Authors: Coetzee, Julie A , Langa, Susana D , Motitsoe, Samuel F , Hill, Martin P
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423967 , vital:72112 , xlink:href="https://doi.org/10.1007/s10750-020-04369-w"
- Description: Floating aquatic weed infestations have negative socio-economic and environmental consequences to the ecosystems they invade. Despite the long history of invasion by macrophytes, only a few studies focus on their impacts on biodiversity, while the ecological benefits of biological control programmes against these species have been poorly quantified. We investigated the process of biotic homogenization following invasion by Pistia stratiotes on aquatic biodiversity, and recovery provided by biological control of this weed. Biotic homogenization is the increased similarity of biota as a result of introductions of non-native species. The study quantified the effect of P. stratiotes, and its biological control through the introduction of the weevil, Neohydronomus affinis on recruitment of benthic macroinvertebrates to artificial substrates. Mats of P. stratiotes altered the community composition and reduced diversity of benthic macroinvertebrates in comparison to an uninvaded control. However, reduction in percentage cover of the weed through biological control resulted in a significant increase in dissolved oxygen, and recovery of the benthic macroinvertebrate community that was comparable to the uninvaded state. This highlights the process of homogenization by an invasive macrophyte, providing a justification for sustained ecological and restoration efforts in the biological control of P. stratiotes where this plant is problematic.
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- Date Issued: 2020
Biological control potential of ectomycorrhizal fungi against Fusarium circinatum on Pinus patula seedlings
- Authors: Chartier FitzGerald, Veronique , Dames, Joanna F , Hawley, Grant L
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425960 , vital:72302 , xlink:href="https://doi.org/10.1080/09583157.2020.1771542"
- Description: The South Africa forestry industry, covering ∼1.3 million hectares, is dependent on exotic pine and Eucalyptus species. Nursery seedlings are not inoculated with ectomycorrhizal (ECM) fungi or other beneficial microbes. Fusarium circinatum is an economically important pathogen affecting seedling survival. The purpose of this investigation was to assess the effects of ectomycorrhizal fungal inoculation on Pinus patula seedling growth and resistance to the fungal pathogen F. circinatum. Explants from ECM basidiocarps, collected from Pinus stands, were plated onto MMN medium to obtain isolates that were then verified via DNA extraction and PCR amplification and sequencing of the ITS rDNA region. These isolates were identified as Boletus edulis f. reticulatus, Lactarius quieticolor, Suillus granulatus and an unknown Suillus species. P. patula growth in the presence of the pathogen F. circinatum was significantly increased and promoted by the L. quieticolor and Suillus isolates. Preventative inoculation of seedlings in the nursery using these isolates would ensure the production of stronger, healthier plants that would be more resistant to F. circinatum infection, increasing survival in the plantation.
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- Date Issued: 2020
Biomes, geology and past climate drive speciation of laminate-toothed rats on South African mountains (Murinae: Otomys)
- Authors: Taylor, Peter J , Kearney, Theresa , Dalton, Desire L , Chakona, Gamuchirai , Kelly, Christopher M , Barker, Nigel P
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425481 , vital:72249 , xlink:href="https://doi.org/10.1093/zoolinnean/zlz134"
- Description: Mitochondrial DNA sequences (1137 bp) of the cytochrome b gene and craniodental and craniometric data were used to investigate the evolutionary relationships of six putative rodent taxa of Otomys (family Muridae: subfamily Murinae: tribe Otomyini) co-occurring in the Western Cape and Eastern Cape provinces of South Africa. Phylogenetic analysis of 20 new sequences together with craniodental and craniometric characters of 94 adult skulls reveal the existence of a unique lineage of Otomys cf. karoensis (named herein Otomys willani sp. nov.) from the Sneeuberg Centre of Floristic Endemism in the southern Drakensberg Mountain Range. Craniometric analysis distinguished O. karoensis from O. willani and identified a further four localities in the range of the latter species. We document southern range extensions of both Sloggett’s ice rat, Otomys sloggetti, and the vlei rat Otomys auratus to the Sneeuberg Mountain Range, in addition to appreciable genetic divergence between Sneeuberg and southern and central Drakensberg populations of O. sloggetti. Our results demonstrate parallel patterns of cryptic speciation in two co-occurring species complexes (Otomys irroratus s.l. and O. karoensis s.l.) associated closely with the boundaries of biomes (fynbos vs. grassland biomes) and geological formations (Cape Fold Belt vs. Great Escarpment).
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- Date Issued: 2020
BTC price volatility: fundamentals versus information
- Authors: Gbadebo, Adedeji Daniel , Adekunle, Ahmed Oluwatobi , Adebayo-Oke Abdulrauf Lukman , Adedokun, Wole , Akande, Joseph
- Date: 2020
- Subjects: Bitcoin price volatility , Bitcoin market fundamentals , Autoregressive Distributed Lag (ARDL)
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/11260/6978 , vital:52630 , https://doi.org/10.1080/23311975.2021.1984624
- Description: This paper offers a plausible response to “what explains the sporadic volatility in the price of Bitcoin?” We hypothesized that market “fundamentals” and “information demands” are key drivers of Bitcoin’s unpredictable price fluctuation. We adopt the transfer-function [Autoregressive Distributed Lag, ARDL] model and its Bounds testing approach to verify how the volatility of the price of Bitcoin responds to its transaction volume, cryptocurrency market capitalisation, world market equity index and Google search. We found the existence of long-run cointegration relation and observed that all the variables except the equity index positively explain the volatility of Bitcoin price. The result established evidence that market fundamentals drive erratic swing in Bitcoin price than information.
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- Date Issued: 2020
Can fishing tourism contribute to conservation and sustainability via ecotourism?: a case study of the Fishery for Giant African Threadfin Polydactylus quadrifilis on the Kwanza Estuary, Angola
- Authors: Butler, Edward C , Childs, Amber-Robyn , Saayman, Andrea , Potts, Warren M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149253 , vital:38819 , https://doi.org/10.3390/su12104221
- Description: It has been suggested that tourism fisheries can raise the value of landed catch, provide alternative livelihoods for local artisanal fishers and, because recreationally caught fishes are often released, simultaneously conserve stocks. However, for fishing tourism to meet ecotourism standards, sustainable, local economic benefit is imperative. This study aimed to assess the direct economic contribution of the recreational fishery for Polydactylus quadrifilis on the Kwanza Estuary, Angola. The recreational fishery contributed significantly to economic productivity in an otherwise rural area, generating a total revenue (TR) of $236,826 per four-month fishing season.
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- Date Issued: 2020
Characterisation of plasmodial transketolases and identification of potential inhibitors: an in silico study
- Authors: Boateng, Rita A , Tastan Bishop, Özlem , Musyoka, Thommas M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429372 , vital:72605 , xlink:href="https://doi.org/10.1186/s12936-020-03512-1"
- Description: Plasmodial transketolase (PTKT) enzyme is one of the novel pharmacological targets being explored as potential anti-malarial drug target due to its functional role and low sequence identity to the human enzyme. Despite this, features contributing to such have not been exploited for anti-malarial drug design. Additionally, there are no anti-malarial drugs targeting PTKTs whereas the broad activity of these inhibitors against PTKTs from other Plasmodium spp. is yet to be reported. This study characterises different PTKTs [Plasmodium falciparum (PfTKT), Plasmodium vivax (PvTKT), Plasmodium ovale (PoTKT), Plasmodium malariae (PmTKT) and Plasmodium knowlesi (PkTKT) and the human homolog (HsTKT)] to identify key sequence and structural based differences as well as the identification of selective potential inhibitors against PTKTs.
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- Date Issued: 2020
Charlie Hebdo as a critical event in a secondary school: Muslim students’ complex positioning in relation to the attack
- Authors: Tize, Carola , Berckmoes, Lidewyde , de Jong, Joop , Reis, Ria
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156400 , vital:39986 , DOI: 10.1177/1363461520903814
- Description: This paper examines responses to the 2015 terror attack on Charlie Hebdo, a French satirical magazine, amongst students in a secondary school in Berlin-Neukölln, Germany. The Charlie Hebdo attack occurred in the final weeks of a 19-month ethnographic study in the community. By analyzing the responses in the school to this critical event, we identify what is at stake for Muslim students.
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- Date Issued: 2020
Chemical archeoceanography:
- Authors: Albarede, Francis , Thibon, Fanny , Blichert-Toft, Janne , Tsikos, Harilaos
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149065 , vital:38801 , https://doi.org/10.1016/j.chemgeo.2020.119625
- Description: Elemental fluxes to the ocean are expected to increase with the surface area of continental exposure to weathering and atmospheric PCO2. The record of phosphorus in sediments, which has no notable source within the ocean, and the radiogenic strontium isotopes in Archean carbonates indicate that, prior to the Great Oxidation Event (GOE), subaerial expanses represented only about 20% of the modern continental surface area, i.e. 7% of the surface of the Earth. Because these simple first-order observations, in contrast to the low oxygen content of the pre-GOE atmosphere, have so far received only little attention in the appraisal of the marine chemistry of the early Earth, a reassessment of the chemistry of the pre-GOE ocean is warranted. Here we discuss some of the geochemical cycles of the Archean world, including protons, alkalinity, electrons, and other electrolytes, and attempt to build a first conceptual framework for Chemical Archeoceanography.
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- Date Issued: 2020
Chemical constituents, antioxidant and cytotoxicity properties of Leonotis leonurus used in the folklore management of neurological disorders in the Eastern Cape, South Africa
- Authors: Tonisi, Sipho , Okaiyeto, Kunle , Hoppe, Heinrich C , Mabinya, Leonard V , Nwodo, Uchechukwu U , Okoh, Anthony I
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429384 , vital:72606 , xlink:href="https://doi.org/10.1007/s13205-020-2126-5"
- Description: In the present study, we evaluated the phytochemical compounds and antioxidant properties of chloroform, ethanol and acetone extracts for leaves and flowers of Leonutus leonurus (L. leonurus) alongside with their cytotoxic effects on human cervical carcinoma (HeLa) cell lines. The phytochemical compounds present in the leaves and flowers of L. leonurus included; phenolics, flavonoids and alkaloids. Their radicals scavenging effects against 2, 2-diphenyl-1-picrylhydrazyl [DPPH] 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonate) [ABTS·+], hydrogen peroxide, nitric oxide as well as metal chelating activities showed dose-dependent activities. Gas chromatography-mass spectrometry (GCMS) analyses revealed the presence of important bioactive compounds, which are associated with antioxidant; and the extracts exhibited toxicity effect against HeLa cells. The findings from this study divulge extracts of L. leonurus as prospective sources of antioxidant and anticancer agents; and hence, further study on their neuroprotective potentials becomes imperative.
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- Date Issued: 2020
Climate modelling suggests a review of the legal status of Brazilian pepper Schinus terebinthifolia in South Africa is required:
- Authors: Martin, Grant D , Magengelele, Nwabisa L , Paterson, Iain D , Sutton, Guy F
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148606 , vital:38754 , https://doi.org/10.1016/j.sajb.2020.04.019
- Description: Brazilian pepper (Schinus terebinthifolia) is a tree native to subtropical South America that was introduced into South Africa in the early 1900s as an ornamental plant. The tree has since escaped cultivation and has invaded ruderal and pristine habitats along the eastern coast of South Africa. Brazilian Pepper is also one of the most problematic invasive alien plants in Florida, USA. We modelled the climatically suitable area for this species in South Africa using MaxEnt, with five distinct datasets: incorporating both the native and the invaded range of the species, as well as different backgrounds.
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- Date Issued: 2020
Climate responsive innovation within the agricultural curriculum and learning system
- Authors: van Staden, Wilma
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/389744 , vital:68479 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/186598"
- Description: The purpose of this paper is to outline the climate responsive innovation process within the agricultural innovation system of the North West Province, South Africa. The focus was on the embedded curriculum and learning activity system and its responses to social-ecological and earth system changes influenced by climate change. It outlines the barriers and processes hampering curriculum and learning innovations towards climate-smart responsiveness, and also examines the processes required to initiate micro and macro innovations. This paper focusses on how actors within the system can initiate curriculum innovation and climate responsiveness through micro innovations when supported and how this can lead to macro innovations. The system experienced various barriers during the innovation process and overcame many challenges during the journey towards climate-smart responsiveness through the identification of contradictions within the system, developing tools to assist in the transitioning process and expansion in the social-spatial dimension by establishing a learning network within the surrounding communities. The research indicated that the catalysing of the curriculum and learning system required specific tools, time and the understanding of the importance of micro-level innovation.
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- Date Issued: 2020
Clinically established biodegradable long acting injectables
- Authors: Nkanga, Christian I , Fisch, Andreas , Rad-Malkshahi, Mazda , Romic, Marieta D , Kittel, Birgit , Ullrich, Thomas , Wang, Jing , Krause, Rui W M , Adler, Sabine , Lammers, Twan , Hennink, Wim E , Ramazani, Farshad
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193386 , vital:45327 , xlink:href="https://doi.org/10.1016/j.addr.2020.11.008"
- Description: Long acting injectable formulations have been developed to sustain the action of drugs in the body over desired periods of time. These delivery platforms have been utilized for both systemic and local drug delivery applications. This review gives an overview of long acting injectable systems that are currently in clinical use. These products are categorized in three different groups: biodegradable polymeric systems, including microparticles and implants; micro and nanocrystal suspensions and oil-based formulations. Furthermore, the applications of these drug delivery platforms for the management of various chronic diseases are summarized. Finally, this review addresses industrial challenges regarding the development of long acting injectable formulations.
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- Date Issued: 2020
Co-loading of isoniazid-grafted phthalocyanine-in-cyclodextrin and rifampicin in crude soybean lecithin liposomes: Formulation, spectroscopic and biological characterization
- Authors: Nkanga, Christian I , Roth, Michael , Walker, Roderick B , Noundou, Xavier S , Krause, Rui W M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183481 , vital:43999 , xlink:href="https://doi.org/10.1166/jbn.2020.2880"
- Description: An inclusion complex of isoniazid-grafted phthalocyanine with gamma-cyclodextrin (Complex) was co-encapsulated with rifampicin (RIF) in crude soybean lecithin liposomes using a heating method. The encapsulation efficiency (%EE) of the Complex-RIF co-loaded liposomes (Rif-Complex-Lips) was determined using UV-Vis spectrophotometry. Rif-Complex-Lips formulations were evaluated using dynamic light scattering, transmission electron microscopy (TEM), 1H-NMR, absorption and emission spectroscopy. Dialysis was used for drug release study in two different media, pH 6.4 and 7.4. HeLa cells were used to assess potential cytotoxicity, and the uptake by lung fibroblasts and epithelial cells was investigated using fluorescence microscopy. The particle size and Zeta potential of Rif-Complex-Lips were approximately 594 nm and –50 mV. Spectroscopic analyses demonstrated molecular distribution of the cargo within the lipid core, and encapsulation efficiency of 58% for Complex and 86% for RIF. TEM analysis unveiled the existence of spherical nanoparticles in our samples, indicating the presence of liposomes. Rif-Complex-Lips exhibited much higher release rates for both INH and RIF at pH 6.4 compared to those tested at pH 7.4. In addition, there was no cytotoxicity on HeLa cells, but remarkable Rif-Complex-Lips internalization by peripheral lung fibroblasts and epithelial cells. Hence, Rif-Complex-Lips are promising vehicles for intracellular delivery of antimicrobial drugs.
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- Date Issued: 2020
Coastal engineers embrace nature: characterizing the metamorphosis in hydraulic engineering in terms of Four Continua
- Authors: Slinger, Jill H , Vreugdenhil, Heleen S I
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163846 , vital:41076 , https://doi.org/10.3390/w12092504
- Description: Hydraulic engineering infrastructures, such as reservoirs, dikes, breakwaters, and inlet closures, have significantly impacted ecosystem functioning over the last two centuries. Currently, nature-based solutions are receiving increasing attention in hydraulic engineering projects and research programs. However, there is a lack of reflection on the concomitant, fundamental changes occurring in the field of hydraulic engineering, and coastal engineering in particular, and what this could mean for sustainability. In this article, we signal the shift from conventional to ecosystem-based hydraulic engineering design and characterize this in terms of four continua: (i) the degree of inclusion of ecological knowledge, (ii) the extent to which the full infrastructural lifecycle is addressed, (iii) the complexity of the actor arena taken into account, and (iv) the resulting form of the infrastructural artefact. We support our arguments with two carefully selected, iconic examples from the Netherlands and indicate how the stretching ideals of ecosystem-based engineering could engender further shifts towards sustainability.
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- Date Issued: 2020
Combination of CTec2 and GH5 or GH26 Endo-Mannanases for Effective Lignocellulosic Biomass Degradation
- Authors: Malgas, Samkelo , Pletschke, Brett I
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429397 , vital:72607 , xlink:href="https://doi.org/10.3390/catal10101193"
- Description: Among endo-mannanases, glycoside hydrolase (GH) family 26 enzymes have been shown to be more catalytically active than GH5 enzymes on mannans. However, only GH5 endo-mannanases have been used for the formulation of enzyme cocktails. In this study, Bacillus sp.-derived GH5 and GH26 endo-mannanases were comparatively analysed biochemically for their synergistic action with a commercial cellulase blend, CTec2, during pre-treated lignocellulose degradation. Substrate specificity and thermo-stability studies on mannan substrates showed that GH26 endo-mannanase was more catalytically active and stable than GH5. GH26 also exhibited higher binding affinity for mannan than GH5, while GH5 showed more affinity for lignocellulosic substrates than GH26. Applying the endo-mannanases in combination with CTec2 for lignocellulose degradation led to synergism with a 1.3-fold increase in reducing sugar release compared to when CTec2 was used alone. This study showed that using the activity of endo-mannanases displayed with model substrates is a poor predictor of their activity and synergism on complex lignocelluloses.
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- Date Issued: 2020
Compounds isolation and biological activities of Piptadeniastrum africanum (hook. f.) Brennan (Fabaceae) roots:
- Authors: Teinkela, Jean E M , Noundou, Xavier S , Mimba, Jeanne E Z , Meyer, Franck , Tabouguia, Octavie M , Nguedia, Jules C A , Hoppe, Heinrich C , Krause, Rui W M , Wintjens, René , Azebaze, Anatole G B
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150084 , vital:38938 , https://doi.org/10.1016/j.jep.2020.112716
- Description: The dicotyledonous plant Piptadeniastrum africanum (hook.f.) Brennan (Fabaceae) is used in traditional medicine to treat various human complaints including bronchitis, coughing, urino-genital ailments, meningitis, abdominal pain, treatment of wounds, malaria and gastrointestinal ailments, and is used as a purgative and worm expeller. The present study describes the phytochemical investigation and the determination of the antimicrobial, antiplasmodial and antitrypanosomal activities of crude extract, fractions and compounds extracted from Piptadeniastrum africanum roots.
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- Date Issued: 2020
Comprehensive data on the mechanical properties and biodegradation profile of polylactide composites developed for hard tissue repairs
- Authors: Aworinde, Abraham K , Adeosun, Samson O , Oyawale, Festus A , Emagbetere, Eyere , Ishola, Felix A , Olatunji, Obafemi , Akinlab, Stephen , Oyedepo, Sunday O , Ajayi, Oluseyi O , Akinlabi, Esther T
- Date: 2020
- Subjects: Regeneration (Biology) , Vickers microhardness , Melt-blending technique
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/3149 , vital:43158 , https://doi.org/10.1016/j.dib.2020.106107
- Description: Africa, the ancestral home of all modern humans, is the most informative continent for understanding the human genome and its contribution to complex disease. To better understand the genetics of schizophrenia, we studied the illness in the Xhosa population of South Africa, recruiting 909 cases and 917 age-, gender-, and residence-matched controls. Individuals with schizophrenia were significantly more likely than controls to harbor private, severely damaging mutations in genes that are critical to synaptic function, including neural circuitry mediated by the neurotransmitters glutamine, γ-aminobutyric acid, and dopamine. Schizophrenia is genetically highly heterogeneous, involving severe ultrarare mutations in genes that are critical to synaptic plasticity. The depth of genetic variation in Africa revealed this relationship with a moderate sample size and informed our understanding of the genetics of schizophrenia worldwide.
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- Date Issued: 2020