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The Ehrhart volume conjecture is false in sufficiently higher dimensions in : The Ehrhart volume conjecture
No full textUsing the method of compression, we show that volume Vol(K)
of a ball K in R^2 with a single lattice point in it’s interior as center of mass satisfies the lower bound...
#find the complete abstract in the attached fil
Fostering Socio-Economic Development in Ghana through Entrepreneurship and Innovation
No full textThe ongoing development problems on the continents, from Africa to Asia, have drawn attention from around the world on numerous occasions in the first few years of the twenty-first century. The gap between industrialized nations and emerging economies is getting wider as government initiatives to support innovation and entrepreneurship become more widespread in those nations. For developing nations, entrepreneurship and innovation have significant potential advantages. To that end, the majority of Sub-Saharan African nations support the growth of small and medium-sized enterprises (SMEs) as a way to reduce poverty, provide jobs, and advance national economic development
Probabilistic Mapping and Spatial Pattern Analysis of Grazing Lawns in Southern African Savannahs Using WorldView-3 Imagery and Machine Learning Techniques
Get PDFSavannah grazing lawns are a key food resource for large herbivores such as blue wildebeest (Connochaetes taurinus), hippopotamus (Hippopotamus amphibius) and white rhino (Ceratotherium simum), and impact herbivore densities, movement and recruitment rates. They also exert a strong influence on fire behaviour including frequency, intensity and spread. Thus, variation in grazing lawn cover can have a profound impact on broader savannah ecosystem dynamics. However, knowledge of their present cover and distribution is limited. Importantly, we lack a robust, broad-scale approach for detecting and monitoring grazing lawns, which is critical to enhancing understanding of the ecology of these vital grassland systems. We selected two sites in the Lower Sabie and Satara regions of Kruger National Park, South Africa with mesic and semiarid conditions, respectively. Using spectral and texture features derived from WorldView-3 imagery, we (i) parameterised and assessed the quality of Random Forest (RF), Support Vector Machines (SVM), Classification and Regression Trees (CART) and Multilayer Perceptron (MLP) models for general discrimination of plant functional types (PFTs) within a sub-area of the Lower Sabie landscape, and (ii) compared model performance for probabilistic mapping of grazing lawns in the broader Lower Sabie and Satara landscapes. Further, we used spatial metrics to analyse spatial patterns in grazing lawn distribution in both landscapes along a gradient of distance from waterbodies. All machine learning models achieved high F-scores (F1) and overall accuracy (OA) scores in general savannah PFTs classification, with RF (F1 = 95.73 ± 0.004%, OA = 94.16 ± 0.004%), SVM (F1 = 95.64 ± 0.002%, OA = 94.02 ± 0.002% ) and MLP (F1 = 95.71 ± 0.003%, OA = 94.27 ± 0.003% ) forming a cluster of the better performing models and marginally outperforming CART (F1 = 92.74 ± 0.006%, OA = 90.93 ± 0.003%). Grazing lawn detection accuracy followed a similar trend within the Lower Sabie landscape, with RF, SVM, MLP and CART achieving F-scores of 0.89, 0.93, 0.94 and 0.81, respectively. Transferring models to the Satara landscape however resulted in relatively lower but high grazing lawn detection accuracies across models (RF = 0.87, SVM = 0.88, MLP = 0.85 and CART = 0.75). Results from spatial pattern analysis revealed a relatively higher proportion of grazing lawn cover under semiarid savannah conditions (Satara) compared to the mesic savannah landscape (Lower Sabie). Additionally, the results show strong negative correlation between grazing lawn spatial structure (fractional cover, patch size and connectivity) and distance from waterbodies, with larger and contiguous grazing lawn patches occurring in close proximity to waterbodies in both landscapes. The proposed machine learning approach provides a novel and robust workflow for accurate and consistent landscape-scale monitoring of grazing lawns, while our findings and research outputs provide timely information critical for understanding habitat heterogeneity in southern African savannahs
Extensions and commonalities in negative existential cycles in Arabic
Get PDFThe many varieties of Arabic together exhibit numerous existential particles, all of them negated with the usual verbal negator mā or occasionally the common Semitic lā. A few of those, ʔys, šī, and bī, exhibit stages of a negative existential cycle. All three cycles share commonalities. Associated with an incipient stage A>B, each undergoes a univerbation between the negator and the existential particle. With the šī cycle, this involves either reflexes of a fusion between the negator mā and šī as māšī, or a further step involving the negator mā, a 3rd-person pronoun hū or hī, and the existential particle šī: mā hū/hī šī > mahūš > mūš > muš/miš. A univerbation of the existential bī proceeds along an analogous pathway: from mā bi through mā hū bi > mahub > mub. As for ʔys, it has fused with the negator lā to form laysa. In all three cycles, these univerbations extend into the domain of equational sentence negation. Another commonality is that as the cycles progress, the original existential particles themselves disappear, to be replaced by new ones. In the bī and šī cycles, it is the preposition fī ‘in’, which has become grammaticalized as an existential particle. In the laysa cycle, existential ʔys is replaced be demonstratives hunāka and θamma ‘there’. The univerbations in all three cycles can operate in sub-domains of verbal negation. The stages that the three cycles have reached permit a comparative diachrony. Because the laysa cycle is the only one to reach a full-on stage C>A, it must be the longest running, followed by the šī cycle, which appears to be entering upon a Stage C in Egyptian Arabic and has done in one southern Yemeni variety. The bī cycle, having reached only an incipient stage A>B and beyond would be the most recent
An Internal Quality Assurance Tool for Higher Education Institutions
No full textThe African Quality Rating Mechanisms (AQRM) is a tool that higher education institutions in Africa can employ to ensure the quality of their programs and processes. It was adopted by the Conference of the African Union Ministers of Education in 2007. In 2018, the African Union Commission handed over the AQRM questionnaire to the AAU, but it was realized that an overhaul of the whole instrument was inevitable. The instrument was re-developed by the AAU and the launch of the African Quality Rating Mechanism (AQRM) for institutional improvement was done on Friday June 3rd 2022, with an overwhelming response
from the whole world.
The AQRM was promoted as part of the Harmonization of African Quality Assurance Programs 1 and 2, during which its contents were improved to take care of emerging issues in higher education, post-COVID.
The HAQAA2 program was able to develop an 0n-line version of the AQRM so that institutions can complete the questionnaires on their own for online analysis.
This tool has been found to be a useful tool for driving institutional internal quality assurance processes. Issues about the validations of institutional self-analysis have been raised. However, institutions are challenged to raise up internal validation teams to check on themselves. The AQRM tool can be used by any institution or by a unit, department or college in an institution. Its current version is to ensure that institutions can promote it to a wider use in their environment
Open Peer Reviewers in Africa Module III Template doc
No full textThis template document, available both in .pdf and .docx format, was developed in the context of a Wellcome Trust funded project to pilot a three-part workshop series called Open Peer Reviewers in Africa. This document is meant to help facilitators lead a preprint review journal club in the context of Module III of the workshop - Module I template slide deck available here; Module II template slide deck available here. Details about the workshop and information about how to run your own version of the workshop can be found in the Trainer Guide
Effect of early age thermal challenge on growth performance, haematological parameters and carcass yield of Indigenous Guinea fowl (Numida meleagris)
No full textSupplemental Materials: https://osf.io/qgwur/This study aimed to evaluate the effect of thermal stress on haematological profile and carcass yield of guinea fowl (GF). A total of 180 one-day old GF keets were assigned to 3 treatments, having 4 replicates of 15 birds each. The treatments were: control (T1); mild heat stress for 6h/day (T2), and high heat stress for 8h/day (T3). Data were collected on weekly body weights, feed intake and feed conversion ratio of the birds. At 6-weeks old, blood samples were collected from 8 GF for determination of haematological profile. At 14-weeks old, 8 birds were also slaughtered per treatment to evaluate relative organ weights, carcass characteristics and immune response. Results showed that the body weight gain and feed intake of the birds of T1 and T2 were similar and significantly higher than that of T3 at week 1 of age. The FCR of the birds in T1 and T2 were also better at this stage. Lymphocyte counts were higher (p<0.01) in the birds of T2 (95 103/mL) than those of the control (93.33 103/mL) and T3 (93.33 103/mL). The weights of lymphoid organs of T2 and T3 birds were higher (p<0.05) than those of the control group. It was concluded that exposure of keets to heat stress for 8h/day had adverse effects on growth performance at the early age but this effect faded with age. The thermal manipulation in this study didn’t influence the carcass yield but improved the weights of lymphoid organs of indigenous GF, indicating a better thermo-tolerance
Untangling Blame And Responsibility For Service Delivery And Local Governance Performance: Testing A Grounded Social Accountability Approach In Tanzania
No full textWe examine the gap between theory and practice in social accountability mechanisms to improve local governance performance in Tanzania. We do so through drawing on an ethnographic investigation tracing lines of blame and responsibility for service delivery, from individual citizens up to the central state incorporating a total of 340 interviews and 12 focused group discussions. We have two keys findings: Firstly, that there is a wide divergence between formal lines of accountability and where actors direct blame for performance failure in practice. Secondly, building a collective understanding of this divergence provides an effective starting point for intervention to improve performance. Our conclusion is that dominant assumptions on social accountability interventions require significant revision in light of our findings
The negative existential cycle in Bantu
No full textRenewal of negation has received ample study in Bantu languages. Still, the relevant literature does not mention a cross-linguistically recurrent source of standard negation, i.e., the existential negator. The present paper aims to find out whether this gap in the literature is indicative of the absence of the Negative Existential Cycle (NEC) in Bantu languages. It presents a first account of the expression of negative existence in a geographically diverse sample of 93 Bantu languages. Bantu negative existential constructions are shown to display a high degree of formal variation within both dedicated and non-dedicated constructions. Although such variation is indicative of change, existential negators do not tend to induce changes at the same level as standard negation. The only clear cases of the spread of an existential negator to the domain of standard negation in this study appear to be prompted by sustained language contact
Ethiopian Archives Of Nature: Photographs
No full text01. Hiking trail between Sankaber and Gich, Simien, 2013.
02. The material shaping of nature: Village of Gich, Simien Mountains, September 2013 and January 2019.
03. An archival collection in the environmental history of Ethiopia: EWCA warehouse, Lideta district, July 2016; EWCA offices, Yobek district, April 2021. (Photographs by Guillaume Blanc [2016] and Kidanemariam Woldegiorgis Ayalew [2021]).
04. The “John Blower” collection: “JB” binders, Ethiopian Wildlife Conservation Authority Library, Addis Ababa, 2016