Mathematical and experimental investigation of water migration in plant xylem

Plant can take water from soil up to several metres high. However, the mechanism of how water rises against gravity is still controversially discussed despite a few mechanisms have been proposed. Also, there still lacks of a critical transportation model because of the diversity and complex xylem structure of plants. This paper mainly focuses on the water transport process within xylem and a mathematical model is presented. With a simplified micro channel from xylem structure and the calculation using the model of water migration in xylem, this paper identified the relationship between various forces and water migration velocity. The velocity of water migration within the plant stem is considered as detail as possible using all major forces involved, and a full mathematical model is proposed to calculate and predict the velocity of water migration in plants. Using details of a specific plant, the velocity of water migration in the plant can be calculated, and then compared to the experimental result from Magnetic Resonance Imaging (MRI). The two results match perfectly to each other, indicating the accuracy of the mathematical model, thus the mathematical model should have brighter future in further applications

Distribution and relative density of trees species in Kainji Lake National Park, Nigeria

The importance of trees in the environment cannot be overemphasized. This present study, therefore, deals with the distribution and relative density of trees species in Kainji Lake National Park. Data were collected using plot sampling techniques. Therein, a 50 by 50 m2 plot was randomly laid. Within each sample plot, data on all trees ≥ 10 cm in diameter at breast height were enumerated. The data were analyzed using descriptive statistics. The result shows that different types of plants species were enumerated in the selected plots. This included six families of trees: Fabiaceae, Caesalpiniaceae, Rubiaceae, Maliaceae, Annonaceae and Mimosaceae. The percentage score of tree species in the four plots reveals that Afzelia africana recorded the highest with a total number of 60 species, followed by Detarium macrocarpium with 47 species, while Anogeissus leiocarpus and Azadirachta indica recorded 31 and 17 species, respectively. Gardenia aqualla was the least species recorded. The density and relative density of Afzelia africana recorded the highest, with 1.2ha and 26.9%, followed by Detarium microcarpiuum with 0.94ha and 21.1%, respectively, while Gardenia aqualla was the least with 0.02 ha and 0.4%. In terms of mean height, Daniela oliveri recorded the highest, with 28.1m, followed by Afzelia africana with 21.8%, while Azadirachta indica was the least with 5.8%. The mean DBH of Entada africana and Anogeissus leiocarpus recorded was 28.7cm and 28.1cm, while Prosopis africana and Accacia gournmaensis recorded 14.0 and 13.4, respectively, which were the least. The Types of wild animal species that are associated with the tree species includes Baboon, Kob, Grim duiker, Francolin, Patas monkey etc. Relative abundance of the animal species shows that Papio anubis recorded the highest with 40.5 individuals, while Erythrocebus patas recorded the least with 2.5 individuals

Gunshot Injuries, A 10-years Experience in a Private Hospital

This paper reports the experience of the authors with 59 cases of gunshot injuries admitted and treated at Lagoon Hospital, a forty-bed private hospital in Lagos, Nigeria, over a 10 year period (1987 - 1996). 44(74.6%) out of the 59 patients were seen in the second half of the study period, that is 1992 – 1996, a period of heightened socio-economic problems and political upheaval. There were 54(91.5%) males and 5(8.5%) females. The average age of the patients was 37.9 years. Of the 59 cases, only 15 (25.4%) patients sustained multiple regions injuries. 44(74.6%) had single region injuries. 40 patients presented to our hospital within 24 hours of the injury. We found this early presentation to be associated with good prognosis. There were altogether two deaths, suggesting a mortality rate of 3.4% among cases to the hospital. NQJHM Vol. 14 (3&4) 2004: pp. 302-30