Michael F. Shaughnessy
An Interview with Stephen Reynolds: Barriers to Critical Thinking
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Book review by Prof. Manuel Alberto M. Ferreira
New Corporate Governance (Successful Board Management Tools)
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Mohamed S. Gouda, Mohamed A.E. Mahmoud, Nader S. Zaki, Ashraf T. Youssef
The role of diffusion weighted MRI study and its quantitative parameter, apparent diffusion coefficient value, to differentiate malignant from benign thyroid nodules
Thyroid nodule evaluation is usually done using ultrasound examination and a fine needle aspiration cytology/biopsy. The aim of this study was to evaluate the role of diffusion weighted imaging to differentiate benign from malignant thyroid nodules. fifty five patients, 3 males (5.5%) and 52 females (49.5%) (17–66 years, mean age 44.4 years) with thyroid nodules were included in the study. Routine MRI of neck and diffusion-weighted MR imaging was performed using b-values 1000. Apparent diffusion coefficient (ADC) values were done for every case. Histopathological results of the thyroidectomy samples were obtained. Comparison of apparent diffusion coefficient values of thyroid nodules with the histopathology was done.The pathology results showed that there were 44 (80%) and 11 (20%) benign and malignant thyroid nodules respectively. The mean maximum diameter of benign and malignant thyroid nodules were 3.5 ±1.3 cm and 2.7± 0.9cm respectively, The mean ADC for being and malignant nodules were 2.10 ±0.49 x10-3 and 1.10 ±0.15x 10-3 respectively. ADC values for benign and malignant thyroid nodules which were significant (p< 0.001).
Nna Prince Joe, Nduudee N. Joy
Comparative studies of the phytochemical screening and proximate potentials of the methanolic extracts of cymbopogon attractus and ocimum gratissimum leaves grown in Nigeria
The phytochemical composition and proximate potentials of cymbopogon attractus and ocimum gratissimum were investigated. The proximate analysis in % showed that ocimum gratissimum had the highest amount of moisture content, ash content, crude protein and carbohydrate of 81.62, 3.03, 5.58 and 8.87 respectively while cymbopogon attractus had the lowest amount of moisture content, ash content, crude protein and carbohydrate with 76.98, 1.69, 2.87 and 8.27 respectively. Though cymbopogon attractus recorded 1.38 and 8.84 for both ether extract and crude fibre while ocimum gratissimum had 0.79 and 3.80 for ether extract and crude fibre respectively.The phytochemical analysis of the plants showed that the two plants contained alkaloid, tannins, saponins, flavonoids, phlobatanin and anthraquinone. While, cardiac glycoside,triterpenoids and reducing compound were found in cymbogopon attractus but absent in ocimum gratssimum. However, the study also revealed that steroid was present in ocimum gratissimum but absent in cymbopogon attractus while protein was not found in both plants. The presence of these phytochemicals account for their medicinal potential as well as their utility as prophylactics. This study showed the presence of steroids in ocimum gratissimum which accounts for its irritative ability in the mouth when rawly eaten while the presence of cardiac glycoside and triterpenoids in cymbopogon attractus are responsible for its sour taste.
Keywords: Proximate, plant extract, phytochemicals, cymbopogon attractus and ocimum gratissimum
Ephraim E. Khansi, Chinyere A. Anyama, Ayi A. Ayi, Jude C. Onwuka
Synthesis and characterization of layered double hydroxide nanostructures and their application in the removal of Fe2+ and Ca2+ ions from oil wells
Four new metal-aluminum layered double hydroxides (LDHs): Mg-Al(OH)2PO4 1, Mg-Al(OH)2PO4PF6 2, Ca-Al(OH)2SO4, 3 and Ca-Al(OH)2PO4PF6 4, were prepared by co-precipitation method followed by mild hydrothermal processing at 60 o C. Mg2+ and Ca2+ in solution with Al3+ was titrated with NaOH over 3-5 h to yield Mg-Al and Ca-Al layered double hydroxides, respectively, incorporating PO43-, PO43-PF6- and SO42- anions in the inter-lamellar spaces. The isolated compounds were characterized with the help of XRD, IR, SEM/EDAX and their ability to remove scale forming ions from aqueous system was studied with the help of Atomic Absorption Spectroscopy (AAS). The SEM micrographs of Mg-O-Al-OH and Ca-O-Al-OH layers intercalated with PO43- and / or [PO4PF6 ]4- anions are similar consisting of uniform nano- spheres with average size of 100 nm, while the M-O-Al-OH layer of compound 3, intercalated with SO42- anions consists of hexagonal nano-plate crystals. In the infrared spectra, the characteristic absorption band for water molecules was observed in all the compounds. The XRD pattern showed that d012 and d104 peaks of M-Al-PO4 LDHs corresponding to interplanar spacing of 3.4804 and 2.5504 Å respectively, shifted to higher 2θ values for M-Al-PO4PF6 system, which indicates a decrease in the interlamellar spacing as PF6 - was incorporated along with PO43- anion. The XRD pattern for Ca-Al-SO4 LDHs was quite different, showing the presence of low angle peaks at 2θ = 11.68 and 14.72o. The results of the column adsorption studies showed that there was a significant removal of Ca2+ by all the compounds under investigation with efficiency of 84-99 %. Whereas compounds 1 and 2 removes Fe2+ effectively with efficiency of 98.73 and 99.77 %, respectively, compounds 3 and 4 were shown to have little or no effect.
Differentiation in the classroom, a cursory review of the literature
Differentiation in the classroom is a method of effectively presenting information to students who may have diverse backgrounds, learning levels, strengths and weaknesses, and different language proficiencies. Providing each student with optimal strategies to learn requires that teachers also have optimal strategies to teach. The current work is an effort that begins to examine differentiation as a teaching strategy for improving student learning, regardless of the diversity within the classroom. Various relevant publications are reviewed and discussed here to define differentiation, to bring to light a wide range of educational concerns, for which differentiation has been considered a possible solution, and to suggest some foundations for differentiation strategies that teachers might employ in the classroom.