International Science and Technology Journal of Namibia (ISTJN)

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Aims and Scope of ISTJN Introduction International Science and Technology Journal of Namibia (ISTJN) is a free, expedited, print and online journal of peerreviewed research and commentary in pure, applied and allied sciences and technology published by the Faculty of Science, University of Namibia. Aims and Scope The journal reflects the multidisciplinary nature of the field of science and technology. It addresses the needs of multiple, interlocking communities, including methodologists in mathematics, statistics and econometrics; as well as basic and applied scientists in biology, chemistry, physics, public health, medicine, education, mining, geology, computing, food, agriculture and engineering. The journal will strive to enhance the level of methodological rigour in pure and applied sciences and will contribute to the development of methodological standards in the fields of science and technology in Namibia. In pursuing its main objective, the journal will also provide a meeting ground for researchers from a number of traditional disciplines and will foster the development of scientific research and publication especially among younger practitioners. Interview corner. Editorial Setup The journal has a dedicated team of editors, who would be academic editors (AE) and experts in the field. Founding Editors: Prof LN Kazembe, Statistics Prof EF Archibong, Chemistry Dr KC Chinsembu, Biological Sciences Prof PM Chimwamurombe, Biological Sciences Prof S. Singh, Physics Advisory Editorial Board: Prof O. Mwandemele, PVC (Academic Affairs and Research), University of Namibia Dr F. Gideon, Dean of Science, University of Namibia Mr A. van Kant, Department of Science and Technology, Ministry of Education Mr E. Shivolo, Ministry of Mines and Energy, Namibia Dr E. Mvula, National Commission on Research, Science & Technology Dr R. Steenkamp, HESS Prof R. Auala, Faculty of Education, UNAM Prof J. Lyaku, Faculty of Agriculture, UNAM Prof P. Odonkor, Faculty of Health Sciences, UNAM Prof I. Davidson, Faculty of Engineering & IT, UNAM Prof C. Esterhuysen, Stellenbosch University, South Africa Prof T. Chirwa, Faculty of Health Sciences, Witwatersrand University, South Africa Prof E. Mwenje, Bindura University of Science Education, Zimbabwe Dr O. Ruzvidzo, North West University, South Africa Prof Ponnadurai Ramasami, University of Mauritius

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Educational Emulation of a Soft Handoff Teaching Model (EESH-TM)
(University of Namibia, 2013) Mbale, Jameson
The use of fixed Base and Mobile Stations offer a set of challenges dealing with the movement of a Mobile Station away from one Base Station toward a second Base Station. In this situation, the signal strength decreases as the distance of the mobile position increases (following an inverse-square law) from the first station; while an increase in signal strength is experienced as the distance decreases from the second one. Gradually the signal from the former is lost. This is a difficult problem in wireless technology, not only to picture but also to solve. This problem which is prominent in mobile and wireless applications is called ”Soft Handoff”, the solution of which applies the concept of ”make-before-break”, which postulates the smooth and gradual transition of signals from the previous Base Station to the next one without causing a sharp break or interruption of the signal. Such a hypothetically smooth and soft hand over signal mechanism is very difficult for students to understand especially those who have had little or no experience with telecommunication equipment, with the analysis of wireless circuits or with hands-on experience with the technology. This became evident when the topic was initially covered in a Telecommunications course at University of Namibia. It was within this context that the Educational Emulation of Soft Handoff Teaching Model (EESH-TM) was designed and developed to model the mechanism of Soft Handoff. The EESH-TM is comprised of: two Base Stations, two Cells, a Mobile Station, and two interacting signals. This teaching model clearly demonstrated, step-by-step, various scenarios with a mobile unit moving between two Base Stations clearly illustrating how Soft Handoff works. Hence, the utilization of this teaching tool presented inexperienced students with an opportunity to observe and understand how signal hand off works in a wireless network. The success of the model was demonstrated by higher examination scores and greater student interest in the topic.
Analytical evaluation of eight-cell cow embryos structure, outwards water and inwards cryo-protectants to ensure successful cryopreservation
(University of Namibia, 2013) Mausse, Francisco; Bezugly, N.
Modern reproductive techniques use cow embryos at different stages of development. Eight-cell embryos feature a layer comprising seven cells (blastomeres), surrounding the inner cell, making a total of eight. This article analyses outwards water paths and inwards cryo-protectants, within the eight-cell cow embryos and effectiveness of their cryopreservation. Reproductive cycles and superovulation in cows were triggered through reproductive hormones injection. After slaughter, oocytes were harvested and eight-cell embryos were produced in vitro fertilization and through embryo culture. The study included morphological observations to visualize embryo structure, distribution of blastomeres, cell-layers and analytical evaluation as well, to assess distribution of penetrating cryoprotectants within the inner-cell mass. Findings based on the eight-cell embryo structure suggest that the quantity of outwards water and inwards cryo-protectants is symmetrically distributed. Although, the characteristic of water and cryo-protectants movement is expected to be much better in eight-cell embryos, cryo-protectants properties and the modality of cryo-protectants should differ from procedures applied in other class of embryos. Survival rate of cryopreserved eight cell embryos was lower (6.3%) as compared to the results for 7–8 days embryos. Obviously, a successful cryopreservation of eight-cell cow embryos can only be achieved through a combination of both technical and biological parameters.
Self-checking impurity method in liquids
(University of Namibia, 2013) Singh, Shyam
We propose a very simple technique for the determination of impurity in liquids based on the refractive index. This technique requires two similar gratings, two similar low power lasers emitting same wavelength and a position detector. The change in refractive index of liquid determines the impurity in a liquid.
Host specificity, prevalence and intensity of infestation of fleas (Order Siphonaptera) of small mammals at selected sites in the city of Windhoek, Namibia
(University of Namibia, 2013) Mfune, John K.; Kangombe, Fransiska; Eiseb, Seth J.
Small mammals host diverse communities of parasites including fleas. There is considerable research interest in effects of parasites on their hosts. Host specificity, prevalence and intensity of infestation of fleas on small mammals were studied at selected sites in the city of Windhoek, Namibia from April to July 2005. Small mammals were live-trapped using Sherman traps and autopsied before collection of fleas. Fleas were processed using standard parasitological procedures and were mounted permanently onto slides using Canada balsam. Small mammal hosts and fleas were identified to species level. A total of sixty one (61) small mammals belonging to four rodent species, i.e. bushveld gerbil Gerbilliscus leucogaster, hairy-footed gerbil Gerbillurus paeba, black-tailed tree rat Thallomys nigricauda and the four-stripped mouse Rhabdomys pumilio and one insectivore, bushveld sengi Elephantulus intufi, were captured. One hundred and thirty six (136) fleas belonging to eight species, i.e. Xenopsylla brasiliensis, Xenopsylla cheopis, Xenopsylla hirsuta, Xenopsylla trispinis, Dinopsyllus ellobius, Dinopsyllus zuluensis, Epirimia aganipes and Listropsylla aricinae were collected from infested hosts. Dinopsyllus ellobius and X. trispinis and L. aricinae were host specific, being collected only from G. leucogaster and G. paeba, respectively. No fleas were collected from E. intifi and R. pumilio. The prevalence of fleas ranged from zero in E. entufi and R. pumilio through 50 % in T. nigricauda, 55.1% in G. leucogaster to 61.1% in G. paeba. High species richness of fleas was recorded in G. leucogaster (seven out of eight flea species) and in G. paeba (six out of eight flea species). The overall prevalence of fleas was higher in male (54.3%) than in female (34.6%) hosts. There was no association between the body mass of small mammal hosts and the intensity of flea infestation. The intensity of infestation of fleas did not vary significantly by host species and sex of hosts.
A Classiﬁcation of Fuzzy Subgroups of Finite Abelian Groups
(University of Namibia, 2013) Gideon, Frednard
The knowledge of fuzzy sets and systems has become a considerable aspect to apply in various mathematical systems. In this paper, we apply a knowledge of fuzzy sets to group structures. We consider a fuzzy subgroups of ﬁnite abelian groups, denoted by G = Zpn +Zqm , where Z is an integer, p and q are distinct primes and m;n are natural numbers. The fuzzy subgroups are classiﬁed using the notion of equivalence classes. In essence the equivalence relations of fuzzy subsets X is extended to equivalence relations of fuzzy subgroups of a group G. We then use the notion of ﬂags and keychains as tools to enumerate fuzzy subgroups of G. In this way, we characterized the properties of the fuzzy subgroups of G. Finally, we use maximal chains to construct a fuzzy subgroups-lattice diagram for these groups of G.
Seasonal changes in avian assemblages in kaokoland (mopane) savanna in the ogongo game reserve, north-central Namibia
(University of Namibia, 2013) Kopij, Grzegorz
Studies were conducted at UNAM Game Reserve (c. 1000 ha) in the BIOTA Observatory ’Ogongo’, which is located c. 50 km NW of Oshakati, north-central Namibia (17 700S, 15 310E). The natural vegetation of this area is the Koakoland (Mopane) Savanna. In 2011-2012, the line transect method has been employed to assess the species composition, dominance structure, and relative abundance of all bird species, and their seasonal changes in the late rainy season (March), middle of dry season (July), and beginning of rainy season (November). In total, 66 resident (46 in late rainy season, only 35 in the middle of dry season and 39 at the beginning of rainy season) and 19 non-resident species were recorded. Only two resident species have been classified as dominants in all three seasons: Plocepasser mahali and Uraeginthus angolensis; five species were dominants in two, and four species in one season. The avian assemblage undergoes significant seasonal changes, mostly related to the water regime in oshanas. Although the number and proportion of dominant species changed only slightly from season to season (6-7 species; 58.8-62.4% of contribution), highly significant seasonal differences in abundance were recorded for 18 resident species. Clear seasonal changes were also found in the proportions of main feeding guilds, i.e. granivores and insectivores. In comparison with other habitats in Namibia, Ogongo Game Reserve has a rich and diverse avifauna. For many bird species the reserve constitutes a safe breeding habitat, and a rich feeding area. It is fully justified to retain its status as nature sanctuary in Cuvelai Drainage ecosystem.
Reconnaissance survey of radioisotopes in soil and possible impact on seasonal Anthrax outbreak at Etosha National Park, Namibia
(University of Namibia, 2013) Hipondoka, Martin; Mauz, B.; Nande, E.M.; Bezuidenhout, J.
Recent discovery of elevated concentrations of uranium and thorium in sediments of the Etosha Pan prompted this reconnaissance study to survey radionuclides for their possible impact on seasonal anthrax outbreaks in habitats adjacent to the pan. Plausible explanation about how animals contract anthrax is yet to be established. Because anthrax spores are non-invasive, one of the preconditions suggested for the initiation of infection is a lesion, which serves as entry point into tissue of the organism. Five samples taken from sediments at waterholes/depressions situated downwind of the pan, where the highest density of anthrax-related deaths occurs, were analysed in the laboratory using a gamma spectrometry. All sites sampled contain concentration of radionuclides higher than the crustal average, and the highest activity concentration of 93 Bq/kg 214Bi and 214Pb, for example, was recorded closest to the Etosha Pan. This suggests that the pan is the source of uranium, and thus possible that radionuclides are redistributed from the pan by prevailing wind, mobilized seasonally by running water and collected in pools in which animals drink. Alpha-emitting radionuclides can damage the renal, gastrointestinal and/or respiratory systems of exposed animals. Incurred damage is hypothesized as a likely mechanism under which spores are aided to enter the host for infection.
Science: An all encompassing field
(University of Namibia, 2013) Kazembe, Lawrence N.; Archibong, Edet F.; Chimwamurombe, Percy M.; Singh, Shyam; Chinsembu, Kazhila C.
What unites science, as Sir David Cox mentioned, is not the subject matter we all work in, but the methodology and the thought process that help solve the problems that arise [1]. Put differently, it is the replicability of its methods, the validity of its findings and reliability of its instruments and techniques. The diversity in science now emphasizes that not a single subject matter will work alone in isolation - especially if you are working in applied sciences, but has to learn from others. Even so, contemporary applied sciences have extended this collaboration to the social sciences [2]. For instance, in implementation science they have learnt to involve social sciences to inform human behaviour if scaling-up of interventions is to be a success.
A distributed water balance model to estimate direct groundwater recharge: A case study from the nhoma and khaudum catchments, Namibia
(University of Namibia, 2013) Wanke, Heike; Dunkeloh, Armin; Udluft, Peter; Wanke, Ansgar
The most important water resource in drylands such as Namibia is groundwater and its recharge including temporal and spatial variations need to be assessed reliably for sustainable water management. In this paper, a grid-based conceptual water balance model with a simplification at the catchment scale level is used to assess groundwater recharge. The reliability of the model predictions are verified by the independent chloride mass balance method. The distributed, process-oriented, physically based water balance model MODBIL used in this study considers the major water balance components and calculates a spatially differentiated water balance by simulating water fluxes and storages at temporal and spatial resolutions based on meteorological, topographic, soil physical, land cover and geological input parameters. In this study it is set up for the upper Khaudum and Nhoma catchments in the Kalahari of north-eastern Namibia and northwestern Botswana at a spatial resolution of 500 x 500 m, calculated daily for a period of 22 years. A mean annual area groundwater recharge of 11.5 mm a􀀀1 is calculated for the catchments, but spatial variations between 0 and 17.5 mm a􀀀1 occur depending on the variability of vegetation, soil and geomorphology. Groundwater recharge only occurred on a few days during the simulation period.
Today, tomorrow, forever
(University of Namibia, 2013) Kazembe, Lawrence N.; Neema, Isak
Early diagnosis and prompt treatment of febrile conditions is a key strategy towards control of the disease from progressing to severe or fatal stages. In this paper, we studied the timing of treatment among children with a history of diarrhoea and fever in Namibia, while simultaneously investigated socio-economic and spatial factors that influence the treatment seeking behaviour. A multinomial probit model with ordered categories was estimated, and results confirmed that there was significant spatial variation at regional level. Socio-economic factors also explain treatment seeking having controlled for spatial dependence. The spatial variation can be interpreted as representing unobserved heterogeneity not captured by the data or possible clustering inherent in nested survey data.
Phytochemical analysis and in vitro anti-plasmodial activity of selected ethnomedicinal plants used to treat malaria associated symptoms in northern Namibia
(University of Namibia, 2013) Nafuka, Sylvia N.; Mumbengegwi, Davis R.
The search for biologically active compounds from plants is of importance for discovery of novel medicine against infectious diseases such as malaria. The aims of this study were to identify ethno-medicinal plants that are used to treat malaria-associated symptoms in traditional settings in northern Namibia; to detect and quantify the presence of major anti-plasmodial phytochemicals to evaluate the anti-plasmodial activity against Plasmodium falciparum 3D7A strain of the extracts of lead plants. Ten plants were identified through a survey conducted by the Multidisciplinary Research Centre at the University of Namibia. Nineteen methanolic extracts from 10 selected ethnomedicinal plants were prepared and analyzed using Thin Layer Chromatography (TLC) to detect classes of anti-plasmodial phytochemical compounds. Furthermore, total phenolic and alkaloids were also quantified. Furthermore, in vitro anti-plasmodial activity of crude methanol and aqueous extracts at 5, 10 and 50 mg/ml was evaluated against P. falciparum 3D7A strain at 1% parasitaemia and 2% hematocrit after 48 hours. The study revealed the presence of at least one of the major anti-plasmodial classes of compounds such as terpenoids, alkaloids, anthraquinones, flavonoids and coumarins in all the plant extracts analyzed. Out of 10 plant species, Mundulea sericea’s shoots indicated the presence of all five major anti-plasmodial phytochemical. The plants species studied show a high estimate of total alkaloids (0.37- 21.21 mg/1g of extracts) and phenolics (99. 58 - 444.07 GA/E mg/ml). Methanol extracts of M. sericea, D. mespiliformis and Cyphostemma spp showed the best anti-plasmodial activity with range of IC50 values from 3.179 to 3.523 mg/ml. The presence of anti-plasmodial phytochemical classes of compounds and high in vitro anti-plasmodial activity of selected plants extracts support the further investigation of these plants, as potential sources of novel anti-plasmodial compounds for malaria drug discovery.
Trace and heavy element distribution of the Hwange Coals in Zimbabwe
(University of Namibia, 2013) Mapani, Benjamin; Finkelman, R.; Ravengai, S.
The study of heavy metals in the Hwange coals enhances knowledge of both the geological evolution of the coal-bearing horizons and the climates that prevailed during their deposition, as well as indicating likely trace and heavy elements that would affect the health of the miners and the environment at large. The Main Coal Seam of the Hwange coals are bracketed by the Lower Wankie Sandstones of Carboniferous to Permian that were deposited during the Dwyka epoch and the Upper Wankie Sandstones of Permian age. The Hwange coals of Zimbabwe are inferred to have been deposited in swamps associated with fresh water lakes lying on either side of a great elevated tract of Archean and Proterozoic basement during the early Permian. Initially the lake was shallow, as observed from sedimentological data, and eventually the lake became deeper during the continuation of the Karoo period of southern Africa. The sedimentation in Zimbabwe began with the melting of the Carboniferous ice cap of the then south and central Africa. The Karoo succession in the Mid-Zambezi Valley suggests that climatic cycles of glacial to semi-glacial and finally to post-glacial nature occurred, followed by very hot, humid and arid conditions towards the end of the sedimentation period. Four sedimentary successions are reflected at Hwange, the first being fluvial-glacial beds, followed by flooding and deposition of the Lower Wankie Sandstones. At the end of this phase, there followed a general increase in flora and fauna, responsible for the formation of coal now preserved in the Main Coal Seam. Above this succession is the Lower Carbonaceous Mudstones of the Wankie succession. The unconformity of the Upper Wankie Sandstones with the Lower Mudstones marks the end of the coal-bearing horizons. Above the Upper Wankie Sandstones further flooding at a large scale occurred, which is thought to have been rapid, as no coal seams are associated with this mudstone in the whole of the Zambezi valley. A systematic study of heavy elements, ash, moisture content and arsenic, shows that during the deposition of the Hwange coals of the Main Coal Seam there were significant amounts of gallium, germanium, niobium, vanadium and chromium in the source areas, together with metals of felsic affinity such as strontium, tin and lithium. There is a systematic relationship between ash content and heavy mineral content in the coal. For coals with a high heavy metal content, their ash contents are low in some samples, whereas others demonstrate the reverse. While we can easily attribute the source of the felsic affliated elements to the basement granites, heavy metals are interpreted to have been fixed under anoxic conditions when the organic matter was being converted to coal. It is suggested that the heavy elements may have acted as catalysts in the coalification processes.
Loop Space Homology of Some Homogeneous Spaces
(University of Namibia, 2013) Gatsinzi, Jean-Baptiste
Let X be a simply-connected compact oriented manifold of dimension m. We show that the Gerstenhaber structure of the loop space homology H (map(S1;X);Q) can be computed in terms of derivations on the minimal Sullivan model of X. The technique is applied to compute brackets in the loop space homology of homogeneous spaces.loop space homology.
Evaluation of bamboo (bambusa vulgaris (schrad)) culm for drip irrigation
(University of Namibia, 2013) Ogedengbe, Kola
Pipes used for irrigation are expensive for small holder farmers. Therefore, bamboo with its pipe-like aerial stem (culm) may be a promising substitute for irrigation pipes. However, there is a dearth of information on the Bamboo Pipe (BP) for this application. The potential of bamboo for agricultural land irrigation was therefore investigated. Medical infusion tubes were forced fixed on the prepared bamboo pipes irrigation unit to act as emitters and Amaranthus hybridus (vegetable) was irrigated as the test crop. Emitters Coefficient of discharge (CVq) and Christiansen Uniformity Coefficient (CUC) were determined during its use for the drip irrigation of Amaranthus hybridus. The results obtained were analysed using Pearson’s correlation coefficient and t-test. The BPs were effective in carrying out drip irrigation (flow rate 0.042 - 0.117 L/hr) of the Amaranthus hybridus. The CVq and CUC varied between 1.82–2.38 and 96.20–98.86 % respectively, which were within acceptable limits. There was negative correlation between CVq and the discharge rate. The maximum yield of Amarathus hybridus obtained was 4.6 kg/m2 (4600 kg/ha) with the medi-emitters discharging at 20 drops/min, a high yield per hectare for an irrigated vegetable.
Distribution of Gamma-Emitting Radionuclides in the Soils of the Neudamm Campus of the University of Namibia, Windhoek, Namibia
(University of Namibia, 2013) Oyedele, James
The concentrations of naturally occurring radionuclides 40K, 232Th and 238U in soil samples taken from the Neudamm campus of the University of Namibia, Windhoek, Namibia have been determined and used to calculate a mean annual effective dose for the campus. The concentrations were measured using a sensitive gamma-ray spectroscopic system consisting of a high purity germanium detector and associated equipment. 40K was found to have the highest specific concentration varying between 229.1 13.5 Bq kg􀀀1 and 499.0 16.5 Bq kg􀀀1 with a mean value of 364.5 79.3 Bq kg􀀀1 while the concentration of 232Th varies between 10.4 2.8 Bq kg􀀀1 and 38.5 3.8 Bq kg􀀀1 with a mean value of 28.0 9.2 Bq kg􀀀1 and the concentration of 238U varies between 11.7 1.3 Bq kg􀀀1 and 24.7 2.1 Bq kg􀀀1 with a mean value of 18.5 4.8 Bq kg􀀀1. The value of 0.05 0.01 mSv y􀀀1 obtained for the mean annual effective dose is well below the limit of 1 mSv y􀀀1 recommended for the public by the International Commission on Radiological Protection. This result indicates that radiation hazard is negligible on the campus.
Relationship between Dissolved Oxygen and the Vertical and Longitudinal Distribution of Zooplankton off the Namibian coast
(Unioversity of Namibia, 2013) Julies, Elsabe M.; Kaholongo, Isak K.
Zooplankton play an important role in the marine food web and are abundant on the Namibian coast, which is part of the highly productive Benguela upwelling system. In the Benguela system zooplankton populations are dominated by copepods and euphausiids. The abundance and distribution of zooplankton are affected by various environmental factors such as temperature, light intensity and dissolved oxygen (DO). This study investigated the relationship between DO and the diversity of zooplankton at different depths in the water column on the continental shelf off the Namibian coast. There was a positive correlation between DO and diversity of zooplankton offshore (Pearson’s r =0.83), while there exists a very weak positive correlation between DO and zooplankton diversity onshore (r= 0.196). Diversity of zooplankton does not differ significantly with depth at both onshore and offshore stations (Shannon’s Index H0 < 1). However, Divesity of zooplankton between offshore (H0=2.8 to 3.6) and onshore (H0=0.8 to 0.9) stations differs significanty (p = 0:0271;d f = 4) in the top 90m, but is not significantly different below 90m (p = 0:406;d f = 4). Nevertheless, the onshore stations had higher species richness compared to the offshore stations. Dissolved oxygen does not have a direct effect on the diversity of zooplankton, but an indirect effect and it is the interplay and interaction between several biological and environmental factors that affects zooplankton assemblage composition.
International joint MSC Programme: University of Namibia and Humboldt University, Germany
(University of Namibia, 2013) Mfune, John K.
The MSc Biodiversity Management and Research Programme is a full time interdisciplinary and international postgraduate programme jointly run by the University of Namibia (Department of Biological Sciences, Faculty of Science) and Humboldt-Universitt zu Berlin, Germany. The main goal of the program is to build capacity to increase the number of postgraduate local and regional experts in the field of Biodiversity Management and Research. This program was designed to ”Build capacity to manage biodiversity and sustainable development in Namibia” as incorporated in Namibia governments ten-year strategic plan of action for sustainable development through biodiversity conservation (National Biodiversity Strategy and Action Plan, 2001-2010). During the programme, students gain in-depth knowledge of natural-spatial features and biological diversity in Southern Africa with emphasis on Namibia, understand ecosystem functioning and human-induced impacts and the economic values and importance of biodiversity. Students also acquire skills that will enable them to design and undertake research to solve practical, relevant problems to society, using scientific methods and techniques. Graduates of the programme are employable in any biodiversity conservation and related fields including but not limited to lecturing, working for the Ministry of Environment and Tourism (National Parks, Scientific Services, Tourism), ecotourism, curators of various taxa at Natural History museums, and community based organizations. Our graduates contribute to management of natural resources, conservation and sustainable use of biodiversity and also contribute to poverty reduction through use of natural resources to improve livelihoods of local people.
On the smoothness and the totally strong properties for nearness frames
(University of Namibia, 2013) Mugochi, Martin M.
In this paper we briefly explore the properties of smooth and totally strong nearness frames. It turns out that there is a relationship between them, in particular, totally strong nearness frames are smooth. We also show that the category of smooth nearness frames is coproductive, and that, as is the case with that of the totally strong ones, it is closed under completions.
On the electronic structure
(University of Namibia, 2013) Archibong, Edet F.
The ground and low-lying excited states of AlS2 and AlS􀀀2 have been studied using density functional theory (DFT) and coupled cluster [CCSD(T)] approximations, in conjunctions with the 6-311+G(2df) one particle basis set. AlS2 is linear with a 2Õg ground state. CCSD(T) predicts that the 2A2 state of the C2v isomer is separated from the ground state by less than 0.1 eV, while the 2Õu and 2å+ u states in D¥h symmetry are located at 0.67 eV and 1.40 eV, respectively, above the 2Õg state. The AlS􀀀2 anion possesses a 1å+ g ground state with a very similar geometry with the neutral molecule. At the CCSD(T) level, adiabatic electron detachment energies for the [AlS2(2Õg) AlS􀀀2 (1å+ g )] transition is 4.03 eV.
Assessment on the effect of Lignin as a feed additive for lohmann brown egg layer chickens: A case study at Neudamm farm, University of Namibia
(University of Namibia, 2014) Mausse, Francisco; Lyaku, Japhet R.; Beukes, Edmond; Nafenya, Lazarus
Namibian environmental conditions. A total of 871 chickens (482 experimental and 489 control groups), weighing an average mass of 2 kg/head, were subjected to an experiment under Neudamm Campus (UNAM) environmental conditions (32 C average temperature and 22% relative humidity). All chickens were fed with ordinary balanced ration earmarked for egg layers for 8 days and subjected to stress for 10 minutes per day. The experimental group was given purified lignin (Lignohumate KD) 60 mg/kg diluted in a litter of drinking water, as an anti-stressor feed additive and metabolic activity stimulator. Results of this study revealed an increase in egg production, reduction in feed intake, resistance to stress, and production of eggs of bigger sizes (graded as Extra-large), with strong shells as compared to those produced by the control group. At a certain stage, some chickens from the experimental group were unable to release eggs freely, a fact possibly related to egg size and possible deficient lubrication of cloacal environment. Studies are ongoing with the objective of identifying accurate amounts of lignin/kg necessary to feed egg-layer chickens for triggering an improvement of egg quality under Namibian environmental conditions, without affecting the bird’s physiology and health.

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