List of Titles

Avian thermoregulation in the heat: is evaporative cooling more economical in nocturnal birds?

- O'Connor, Ryan S, Smit, Ben, Talbot, William A, Gerson, Alexander R, Brigham, R Mark, Wolf, Blair O, McKechnie, Andrew E

Authors: O'Connor, Ryan S , Smit, Ben , Talbot, William A , Gerson, Alexander R , Brigham, R Mark , Wolf, Blair O , McKechnie, Andrew E
Date: 2018
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/441518 , vital:73895 , https://journals.biologists.com/jeb/article/221/17/jeb181420/19595/Avian-thermoregulation-in-the-heat-is-evaporative
Description: Evaporative cooling is a prerequisite for avian occupancy of hot, arid environments, and is the only avenue of heat dissipation when air temperatures (Ta) exceed body temperature (Tb). Whereas diurnal birds can potentially rehydrate throughout the day, nocturnal species typically forgo drinking between sunrise and sunset. We hypothesized that nocturnal birds have evolved reduced rates of evaporative water loss (EWL) and more economical evaporative cooling mechanisms compared with diurnal species, permitting nocturnal species to tolerate extended periods of intense heat without becoming lethally dehydrated. We used phylogenetically informed regressions to compare EWL and evaporative cooling efficiency [ratio of evaporative heat loss (EHL) and metabolic heat production (MHP); EHL/MHP] among nocturnal and diurnal birds at high Ta. We analyzed variation in three response variables: (1) slope of EWL at Ta between 40 and 46°C, (2) EWL at Ta=46°C and (3) EHL/MHP at Ta=46°C. Nocturnality emerged as a weak, negative predictor, with nocturnal species having slightly shallower slopes and reduced EWL compared with diurnal species of similar mass.
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Date Issued: 2018

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Biological control of Salvinia molesta in South Africa revisited

- Martin, Grant D, Coetzee, Julie A, Weyl, Philip S R, Parkinson, Matthew C, Hill, Martin P

Authors: Martin, Grant D , Coetzee, Julie A , Weyl, Philip S R , Parkinson, Matthew C , Hill, Martin P
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/103878 , vital:32318 , https://doi.org/10.1016/j.biocontrol.2018.06.011
Description: The aquatic weed Salvinia molesta D.S. Mitch. (Salviniaceae) was first recorded in South Africa in the early 1900s, and by the 1960s was regarded as one of South Africa’s worst aquatic weeds. Following the release of the weevil, Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) in 1985, the weed is now considered under successful biological control. However, the post-release evaluation of this biological control programme has been ad hoc, therefore, to assess the efficacy of the agent, annual quantitative surveys of South African freshwater systems have been undertaken since 2008. Over the last ten years, of the 57 S. molesta sites visited annually in South Africa, the weevil has established at all of them. Eighteen sites are under successful biological control, where the weed no longer poses a threat to the system and 19 are under substantial biological control, where biological control has reduced the impact of the weed. Since 2008, the average percentage weed cover at sites has declined significantly from 51–100% cover to 0–5% cover in 2017 (R2 = 0.78; P < 0.05). Observations of site-specific characteristics suggest that biological control is most effective at small sites and more difficult at larger and shaded sites. Our findings show that S. molesta remains under good biological control in South Africa, however, some sites require intermittent strategic management, such as augmentative releases of C. salviniae.
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Date Issued: 2018

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Conservation and human livelihoods at the crossroads: Local needs and knowledge in the management of Arabuko Sokoke Forest

- Chiawo, David O, Kombe, Wellington N, Craig, Adrian J F K

Authors: Chiawo, David O , Kombe, Wellington N , Craig, Adrian J F K
Date: 2018
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/448843 , vital:74765 , https://doi.org/10.1111/aje.12462
Description: Arabuko Sokoke Forest is the largest remaining single block of indigenous dry coastal tropical forest in Eastern Africa. Households within a 5 km buffer zone depend heavily on the forest for their livelihood needs, and the pressure on forest resources is on the increase. In May 2015, 109 households were interviewed on resources they obtain from the forest, in terms of the self‐reported level of monthly income. We found household income and farm size significantly positively correlated with benefits from the forest, highlighting the possible influence of household wealth in exploiting forest resources. A large proportion of households (32%) had limited knowledge of local birds, while human–bird conflict was reported by 44% of the households. While many households were keen to participate in conservation projects that maintain the forest, 44% had no knowledge of the forest management plan, and 60% of those interviewed had no idea of how forest zones were designated for particular activities. Drivers for local community participation in conservation projects appear to be sustainable income and fulfilment of basic household needs.
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Date Issued: 2018

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Economic evaluation of wetland restoration: a systematic review of the literature

- Browne, Michelle, Fraser, Gavin C G, Snowball, Jeanette D

Authors: Browne, Michelle , Fraser, Gavin C G , Snowball, Jeanette D
Date: 2018
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/471292 , vital:77438 , https://doi.org/10.1111/rec.12889
Description: Evaluating the outcomes of wetland restoration projects is critical to improve practice and justify further investment in wetland restoration. We conducted a systematic literature review to evaluate the current state of knowledge on the economic valuation of the outcomes of wetland restoration. We assessed the economic methods applied, the attributes valued, and the timing of the evaluation in relation to the age of restoration along with publication trends. Research on the topic is increasing, but studies from Africa and South America are lacking. A diverse cross‐disciplinary interest is notable, yet collaborations between disciplines are less frequent. Of particular concern is that only a third of the studies were undertaken postrestoration, and even fewer for restorations older than 10 years. Gaps in the knowledge base mean that our present understanding of the value achieved through wetland restoration is tentative. The need for postrestoration site‐specific valuation efforts remains large both to justify further investment and to improve confidence in predictive and value transfer approaches as practical tools to inform decision‐making.
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Date Issued: 2018

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Gender and popular imaginaries in Africa:

- Spencer, Lynda G, Ligaga, Dina, Musila, Grace

Authors: Spencer, Lynda G , Ligaga, Dina , Musila, Grace
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/138860 , vital:37679 , DOI: 10.1080/10130950.2018.1526467
Description: If we accept that many Africans’ social perceptions on a range of questions, including gender, are shaped by popular cultural productions which retain a keen pulse on the everyday, then it is important to reflect on the interface between gender and popular imaginaries. The debate on the definition of the ‘popular’ remains an open one with multiple interpretations and categories. This contestation in itself gestures towards popular culture’s inclination for ambiguity and slipperiness. As Karin Barber (2018:13) reminds us, the popular constitutes “expressive forms that are constantly emergent, ephemeral, embedded in daily life, given to extraordinary bursts of activity and rapid transformation”. For George Ogola, popular cultural forms “engage with and subject the polity to constant critique through informal but widely recognised forms of censure” (2017:2). In this special issue, we use popular imaginaries to mean the range of cultural productions, platforms, and interactions between consumers and producers - which are often interchangeable - that capture the material, the affective, as inflected and refracted in different texts, contexts and platforms.
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Date Issued: 2018

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Practice intentions at entry to and exit from medical schools aspiring to social accountability: findings from the Training for Health Equity Network Graduate Outcome Study

- Iputo, Jehu, Sarah Larkins , Karen Johnston, John C. Hogenbirk, Sara Willems, Salwa Elsanousi, Marykutty Mammen, Kaatje Van Roy, Jehu Iputo , Fortunato L. Cristobal , Jennene Greenhill, Charlie Labarda11 and Andre-Jacques Neusy

Authors: Iputo, Jehu , Sarah Larkins , Karen Johnston, John C. Hogenbirk, Sara Willems, Salwa Elsanousi, Marykutty Mammen, Kaatje Van Roy, Jehu Iputo , Fortunato L. Cristobal , Jennene Greenhill, Charlie Labarda11 and Andre-Jacques Neusy
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/11260/5415 , vital:44567 , https://pubmed.ncbi.nlm.nih.gov/30424760/
Description: Background: Understanding the impact of selection and medical education on practice intentions and eventual practice is an essential component of training a fit-for-purpose health workforce distributed according to population need. Existing evidence comes largely from high-income settings and neglects contextual factors. This paper describes the practice intentions of entry and exit cohorts of medical students across low and high income settings and the correlation of student characteristics with these intentions. Methods: The Training for Health Equity Network (THEnet) Graduate Outcome Study (GOS) is an international prospective cohort study tracking learners throughout training and ten years into practice as part of the longitudinal impact assessment described in THEnet’s Evaluation Framework. THEnet is an international community of practice of twelve medical schools with a social accountability mandate. Data presented here include cross-sectional entry and exit data obtained from different cohorts of medical students involving eight medical schools in six countries and five continents. Binary logistic regression was used to create adjusted odds ratios for associations with practice intent. Results: Findings from 3346 learners from eight THEnet medical schools in 6 countries collected between 2012 and 2016 are presented. A high proportion of study respondents at these schools come from rural and disadvantaged backgrounds and these respondents are more likely than others to express an intention to work in underserved locations after graduation at both entry and exit from medical school. After adjusting for confounding factors, rural and low income background and regional location of medical school were the most important predictors of intent to practice in a rural location. For schools in the Philippines and Africa, intention to emigrate was more likely for respondents from high income and urban backgrounds.
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Date Issued: 2018

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Spectral study of radioluminescence in carbon-doped aluminium oxide

- Nyirenda, Angel N, Chithambo, Makaiko L

Authors: Nyirenda, Angel N , Chithambo, Makaiko L
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/110067 , vital:33220 , https://doi.org/10.1016/j.radmeas.2018.06.026
Description: The spectral emission study of the radioluminescence (RL) measured from carbon-doped aluminium oxide (α-Al2O3:C) at various temperatures between 30 and 300∘C is reported. The energy-resolved RL emission spectra measured at room temperature show seven gaussian emission bands centred at 1.75, 1.79, 1.85, 2.22, 2.96, 3.72 and 4.44 eV. The 2.96-eV emission, associated with F-centres, is the primary RL emission whereas the narrow (R-line) emission centred at 1.79 eV, associated with Cr3+ impurity ions, is the most intense secondary emission. However, the intensity of 1.79-eV emission decreases with repeated RL measurements. The central emission energy for F-centres is constant throughout the temperature range of investigation. The full width at half maximum (FWHM) for the F-centre emission band increases with temperature whereas the F-centre peak intensity exhibits thermal quenching behaviour at temperatures above 160∘C. On the other hand, the emission energy for the R-line emission of Cr3+ is constant for temperatures between 30 and 160∘C, whereas its peak intensity generally decreases with temperature. F-centres experience strong-coupling in their crystallographic sites with estimated electron-lattice coupling parameters of S = 5.0 ± 0.9, Ep = 0.079 ± 0.008 eV and ν = 1.91 × 1013 Hz where S, Ep and ν are the Huang-Rhys factor, the phonon energy and the phonon frequency, respectively. The RL spectra recorded while ramping the temperature of a sample at a constant rate have been compared against conventional TL spectra.
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Date Issued: 2018

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The effect of pre-dose on thermally and optically stimulated luminescence from α-Al2O3C, Mg and α-Al2O3: C

- Kalita, Jitumani M, Chithambo, Makaiko L

Authors: Kalita, Jitumani M , Chithambo, Makaiko L
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/111011 , vital:33363 , https://doi.org/10.1016/j.apradiso.2018.06.012
Description: We report the effect of pre-dose on the thermoluminescence (TL) and optically stimulated luminescence (OSL) dose response of α-Al2O3:C,Mg and α-Al2O3:C. Before any luminescence measurement, the samples were irradiated with different doses, namely 100, 500 and 1000 Gy to populate the deep electron traps. This is the pre-dose. The results from TL and OSL studies are compared with results from samples used without any pre-measurement dose. The TL glow curves and OSL decay curves of α-Al2O3:C,Mg recorded after pre-doses of 100, 500 and 1000 Gy are identical to those from a sample used without any pre-dose. Further, the TL and OSL dose response of all α-Al2O3:C,Mg samples are similar regardless of pre-dose. In comparison, the TL glow curves and OSL decay curves of α-Al2O3:C are influenced by pre-dose. We conclude that the differences in the TL and OSL dose response of various pre-dosed samples of α-Al2O3:C are due to the concentration of charge in the deep traps. On the other hand, owing to the lower concentration of such deep traps in α-Al2O3:C,Mg, the TL or OSL dose responses are not affected by pre-dose in this material.
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Date Issued: 2018

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Thermoluminescence of α-Al2O3: C, Mg annealed at 1200° C

- Kalita, Jitumani M, Chithambo, Makaiko L

Authors: Kalita, Jitumani M , Chithambo, Makaiko L
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/111030 , vital:33365 , https://doi.org/10.1016/j.nimb.2018.03.003
Description: Stimulated luminescence in α-Al2O3:C,Mg has thus far been studied for samples annealed at temperature no higher than 900 °C as can be seen by an examination of the literature. We report the thermoluminescence (TL) features of α-Al2O3:C,Mg annealed at 1200 °C. A glow curve measured at 1 °C/s from the samples annealed at 1200 °C shows eight peaks at 54, 80, 102, 173, 238, 290, 330 and 387 °C. Kinetic analyses show that the peak at 54 °C follows general order kinetics (b = 1.3) whereas the rest follow first order kinetics. The values of the activation energy of the peaks are between 0.77 eV and 1.90 eV and the frequency factors are of the order of 1010–1014 s−1. The intensity of the peaks at 54, 80, 102 and 173 °C increase with heating rate whereas those of the peaks at 238 and 290 °C decrease with heating rate. The decrease of intensity of the peaks at 238 and 290 °C with heating rate is due to thermal quenching whereas the increase of intensity of the peaks with heating rate indicates an inverse thermal-quenching-like behaviour. Interestingly this behaviour is observed only after annealing at 1200 °C. The activation energy for thermal quenching as calculated using the peaks at 238 and 290 °C are (1.02 ± 0.16) eV and (1.33 ± 0.15) eV respectively. Regarding the dosimetric features, the dose response of the peaks at 54, 80 and 102 °C are sublinear within 1–10 Gy and the peak at 54 °C saturates above 6 Gy. In contrast, the response of the peak at 173 °C is sublinear with 1–4 Gy and superlinear between 4 and 10 Gy. The peaks are found to fade at different rates and the rate of fading is also affected by annealing.
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Date Issued: 2018

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Species distribution and antifungal susceptibility patterns of Candida isolates from a public tertiary teaching hospital in the Eastern Cape Province, South Africa

- Mnge, P, Okeleye, B I, Vasaikar, S D, Apalata, T

Authors: Mnge, P , Okeleye, B I , Vasaikar, S D , Apalata, T
Date: 2017-03-14
Subjects: Candida Candida species , Antifungal agents Antifungal susceptibility
Language: English
Type: text , article
Identifier: http://hdl.handle.net/11260/6817 , vital:49389 , http://dx.doi.org/10.1590/1414-431X20175797
Description: Candida species are the leading cause of invasive fungal infections, and over the past decade there has been an increased isolation of drug resistant Candida species. This study aimed to identify the species distribution of Candida isolates and to determine their unique antifungal susceptibility and resistance patterns. During a cross-sectional study, 209 Candida isolates (recovered from 206 clinical samples) were collected and their species distribution was determined using ChromAgar Candida. The Vitek-2 system (Biomerieux, South Africa) was used to determine minimum inhibitory concentrations (MICs) to azoles (fluconazole, voriconazole), echinocandins (caspofungin, micafungin), polyenes (amphotericin B) and flucytosine. Four species of Candida were isolated, of which C. albicans was the most frequent, isolated in 45.4 percent (95/209) of the isolates, followed by C. glabrata: 31.1 percent (65/209). The MICs of the different antifungal drugs varied amongst the species of Candida. From the 130 isolates tested for MICs, 90.77 percent (112/130) were susceptible to all antifungal drugs and 6.9 percent (9/130) of the isolates were multi-drug resistant. C. dubliniensis (n=2) isolates were susceptible to all the above mentioned antifungal drugs. There was no significant difference in species distribution amongst clinical specimens and between patients’ genders (P40.05). An increase in MIC values for fluconazole and flucytosine towards the resistance range was observed. To our knowledge, this is the first report on surveillance of Candida species distribution and antifungal susceptibility at a public tertiary teaching hospital in Eastern Cape, South Africa.
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Date Issued: 2017-03-14

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A privacy and security threat assessment framework for consumer health wearables

- Mnjama, Javan, Foster, Gregory G, Irwin, Barry V W

Authors: Mnjama, Javan , Foster, Gregory G , Irwin, Barry V W
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/429217 , vital:72568 , https://ieeexplore.ieee.org/abstract/document/8251776
Description: Health data is important as it provides an individual with knowledge of the factors needed to be improved for oneself. The development of fitness trackers and their associated software aid consumers to understand the manner in which they may improve their physical wellness. These devices are capable of collecting health data for a consumer such sleeping patterns, heart rate readings or the number of steps taken by an individual. Although, this information is very beneficial to guide a consumer to a better healthier state, it has been identified that they have privacy and security concerns. Privacy and Security are of great concern for fitness trackers and their associated applications as protecting health data is of critical importance. This is so, as health data is one of the highly sort after information by cyber criminals. Fitness trackers and their associated applications have been identified to contain privacy and security concerns that places the health data of consumers at risk to intruders. As the study of Consumer Health continues to grow it is vital to understand the elements that are needed to better protect the health information of a consumer. This research paper therefore provides a conceptual threat assessment framework that can be used to identify the elements needed to better secure Consumer Health Wearables. These elements consist of six core elements from the CIA triad and Microsoft STRIDE framework. Fourteen vulnerabilities were further discovered that were classified within these six core elements. Through this, better guidance can be achieved to improve the privacy and security of Consumer Health Wearables.
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Date Issued: 2017

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Application of the Morita-Baylis-Hillman reaction in the synthesis of 3-[(N-cycloalkylbenzamido)methyl]-2-quinolones as potential HIV-1 integrase inhibitors

- Sekgota, Khethobole C, Majumder, Swarup, Isaacs, Michelle, Mnkandhla, Dumisani, Hoppe, Heinrich C, Khanye, Setshaba D, Kriel, Frederik H, Coates, Judy, Kaye, Perry T

Authors: Sekgota, Khethobole C , Majumder, Swarup , Isaacs, Michelle , Mnkandhla, Dumisani , Hoppe, Heinrich C , Khanye, Setshaba D , Kriel, Frederik H , Coates, Judy , Kaye, Perry T
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66178 , vital:28913 , https://doi.org/10.1016/j.bioorg.2017.09.015
Description: publisher version , A practicable six-step synthetic pathway has been developed to access a library of novel 3-[(N-cycloalkylbenzamido)methyl]-2-quinolones using Morita-Baylis-Hillman methodology. These compounds and their 3-[(N-cycloalkylamino)methyl]-2-quinolone precursors have been screened as potential HIV-1 integrase (IN) inhibitors. A concomitant survey of their activity against HIV-1 protease and reverse-transcriptase reveals selective inhibition of HIV-1 IN.
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Date Issued: 2017

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Between a cushion and a risky conversation: ARTS LOUNGE reviewed

- Baasch, Rachel M

Authors: Baasch, Rachel M
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/147703 , vital:38662 , https://doi.org/10.1080/00043389.2011.11877155
Description: On the fringe of the National Arts Festival, at a point of transition between Rhodes University campus and the commercial side of Grahamstown, the walls of a former home and former horse-stable, now a research house, reverberate with the strain of cross-disciplinary, site-specific collaboration. The ARTS LOUNGE made its first official appearance at the Grahamstown National Arts Festival (ViPPA Research Center, Rhodes University) from 30 June to 9 July 2011. The ten-day event was organised by the Visual and Performing Arts of Africa Research (ViPPA) team in collaboration with musicians, artists, writers, performers and members of the public.
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Date Issued: 2017

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Change Drivers at the front lines of the future: rising cultures for sustainability education in contemporary South Africa

- Kulundu, Injairu

Authors: Kulundu, Injairu
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/437107 , vital:73331 , ISBN 978-0-620-79605-7 , https://doi.org/10.3920/978-90-8686-846-9_33
Description: This chapter asks us to regenerate and re-imagine what a dis-tinctively young and contemporary feeling of Environmental and Sustainability Education could look like in the African con-text. It asks us to acknowledge the ingenious ways that Change Drivers in South Africa and Africa are moving towards their visions of the common good. The chapter invites us to trace and learn from the transgressive learning and nomadic journeys of young Change Drivers who are part of a network called Activate! Change Drivers. Activate! Change Drivers is one of the largest youth led movements in South Africa. It is a network of young leaders equipped to drive change for the common good in South Africa. In a world that is uncertain and unknown the embodied knowledge of Change Drivers in South Africa can help us as practitioners think carefully and critically about how to learn for an unknown and predominantly young future.
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Date Issued: 2017

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Design and application of link: A DSL for network frame manipulation

- Pennefather, Sean, Irwin, Barry V W

Authors: Pennefather, Sean , Irwin, Barry V W
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/429230 , vital:72569 , https://ieeexplore.ieee.org/abstract/document/8251774
Description: This paper describes the design and application of Link, a Domain Specific Language (DSL) targeting the development of network applications focused on traffic manipulation at the frame level. The development of Link is described through the identification and evaluation of intended applications and an example translator is implemented to target the FRAME board which was developed in conjunction with this research. Four application examples are then provided to help describe the feasibility of Link when used in conjunction with the implemented translator.
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Date Issued: 2017

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Effects of an eight-week stepladder exercise protocol on lower limb muscular strength of apparently healthy young adults

- Olagbegi, Oladapo M, Adegoke, Babatunde O, Christie, Candice J, Bolarinde, Olufemi S, Jegede, Joseph A

Authors: Olagbegi, Oladapo M , Adegoke, Babatunde O , Christie, Candice J , Bolarinde, Olufemi S , Jegede, Joseph A
Date: 2017
Language: English
Type: article , text
Identifier: http://hdl.handle.net/10962/59974 , vital:27716 , doi: 10.1515/humo-2017-0026
Description: Purpose. backward descent of stairs is associated with improved muscle strength and reduced joint stress, but the effect of backward ascent of stairs on lower limb muscle strength has not been reported. This study compared the effects of forward and backward stair climbing on lower limb muscle strength in apparently healthy young adults. Methods. The total of 31 young volunteers were allocated to either forward or backward stair climbing group (n = 16 and 15, respectively). Dynamic quadriceps and hamstring muscle strength was assessed in addition to thigh girth at baseline and at weeks 4 and 8 with the use of the repetitive maximum method and tape measure, respectively. Results. Between baseline and week 8, muscular strength in both groups (quadriceps: 14.4 ± 3.6 to 16.4 ± 3.4 kg; 14.0 ± 2.9 to 15.3 ± 2.7 kg; hamstring: 12.2 ± 3.2 to 13.4 ± 3.2; 11.7 ± 2.5 to 12.9 ± 2.7 kg) increased significantly (p<0.05) while the increase in thigh girth was not significant (p>0.05). The groups were comparable in all three measures post intervention. Conclusions. Forward and backward stair climbing protocols are effective for improving the dynamic strength of the hamstring and quadriceps muscles of apparently healthy young adults. Thus, either protocol could be used for the improvement of lower limbs dynamic muscle strength.
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Date Issued: 2017

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Evolution of foraging behaviour: Deep intra-generic genetic divergence between territorial and non-territorial southern African patellid limpets

- Mmonwa, Kolobe L, Teske, Peter R, McQuaid, Christopher D, Barker, Nigel P

Authors: Mmonwa, Kolobe L , Teske, Peter R , McQuaid, Christopher D , Barker, Nigel P
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/444798 , vital:74299 , https://doi.org/10.1016/j.ympev.2017.05.024
Description: Southern Africa is a biodiversity hotspot of patellid limpets, with three genera (Helcion, Cymbula and Scutellastra) identified and described in the region. Scutellastra is the most diverse and most frequently studied of these and, along with Cymbula, includes species with territorial and non-territorial foraging behaviours. We used three mitochondrial markers (12S rRNA, 16S rRNA and COI) and one nuclear marker (ATPSβ intron) to assess evolutionary relationships among species of Cymbula and Scutellastra with these two foraging behaviours and to identify which foraging mode is the more ancient. Maximum Likelihood and Bayesian Inference phylogenetic analyses revealed that the species sharing a foraging type are monophyletic in both genera. Territoriality is a derived character, as the clades with this foraging type are nested within a tree that otherwise comprises non-territorial taxa. These include Helcion, which was recovered as sister to the Cymbula/Scutellastra clade, and the next basal genus, Patella, which is ancestral to all southern African patellogastropods. Deep genetic divergence between the two foraging traits reflects strong adaptive effects of resource partitioning in the evolution of southern African patellid limpets.
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Date Issued: 2017

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