Coordination of Cu(II) and Ni(II) in polymers imprinted so as to optimize amine chelate formation

Molecular imprinting has become an established technique. However, little was done on direct investigation of the sorbents produced. In the present work, en ESR method was used for the investigation of the complex formation processes within the sorbents imprinted with copper(II) and nickel(II). The sorbents were synthesized from a mixture of linear low molecular weight polyethyleneimine oligomers. The composition, structure and distribution of complexes in the resin phase were investigated. The effects of the synthesis conditions, loading degree and water content were examined. The presence of certain copper complexes was found to be a convenient characteristic of the imprinting efficiency. The optimum synthesis conditions for obtaining sorbents imprinted with copper(II) or nickel(II) were identified. The imprinting results in the improvement of the stability of the complexes and the selectivity and working capacity of the sorbents. The imprinted samples are also characterized by a more even distribution of chelating sites. The synthesis conditions and loading by ions allow for the regulation of the ratio between individual complexes and magnetic associates in the resin phase. This is a critical point on the future use of the metal containing imprinted sorbents as catalysts. (C) 2003 Published by Elsevier Science Ltd

Malaria and Hepatitis B co-infection in patients with febrile illnesses attending general outpatient unit of the Murtala Muhammed Specialist Hospital, Kano, Northwest Nigeria

Malaria and Hepatitis B Virus (HBV) infections are co-endemic throughout much of the tropical and sub-Saharan Africa and both present major threat to public health. A study on the prevalence of HBV and Malaria co-infection was carried out on 200 patients presenting with fever at the General Outpatient Department (GOPD) of the Murtala Muhammed Specialist Hospital (MMSH), Kano using Gold Standard microscopy and rapid diagnostic test (RDT). The effect of mono and co-infection on hematological parameters was also investigated. Fifty one (25.5%) out of the 200 patients studied were Malaria  positive. Females had higher prevalence rate(18%) of Malaria infection than males with 7.5%. Age group 15-24 had the highest Malaria prevalence (11%) followed by age group 25-34 with 6.5%. Higher mean  parasite density (1,200/ìl) was recorded among subjects with monoinfection of Malaria than mean parasite density (518/ìl) obtained among the co-infected. Mean parasite density was higher in female than male subjects. Thirteen (6.5%) subjects were HBV positive. Males had higher rate of infection with 4.5% prevalence than females with 2.0%. Nine individuals representing 4.5% of the total population had  co-infection with higher prevalence (3%) among the males. Age groups 25-34 were observed to have high co-infection rate of 1.5% and the least prevalence was observed among the age group 15-24 with 0.5%  prevalence for both males and females. Hematological evaluation carried out on all the categories of  subjects shows significant difference in mean values of PCV (P=0.041), Hb (P=0.018) between the  co-infection group and those with malaria infection and control groups. However, no significant difference (P>0.05) was observed in the values of WBC, PLT and Red cell indices among the co-infected and other test group. It was concluded that co-infection with the two ailments had no profound effect on hematologic parameters.Keywords: Co-Infection, Hepatitis B, Kano, Malaria, MMSH, Prevalenc

A morphometric study of the sella turcica: race, age, and gender effect

Background: The aim of this study was to evaluate the morphological appearance, bridging incidence, and linear dimensions of sella turcica (ST) in Chinese and Nepalese individuals. Materials and methods: This retrospective study examined digital standardised lateral cephalometric of 360 Chinese and Nepalese subjects, which consisted of 116 females and 64 males with an age range of 8–28 years. The sella morphology, bridging, and size were assessed on the lateral cephalometric radiographs, and the data were correlated with race, gender, and age. Results: Sella turcica presented a normal morphology in most Nepalese (90%) subjects whereas flat-shaped morphology were highly prevalent among Chinese subjects (36.7%). The frequency of full bridging was 2.8% and 11.7% for Chinese and Nepalese subjects, respectively. When the race was compared with sella size, a statistically significant difference was detected in length (p < 0.05) and diameter (p < 0.001) of ST. A significant correlation was found between length and diameter of the ST and age in Chinese and Nepalese subjects. No significant correlation was observed between the size of ST and gender of Chinese and Nepalese subjects. The only parameter significantly associated with race, age and gender was the diameter of ST. Conclusions: These findings assist orthodontists, neurosurgeons, and forensic medical investigators to focus on the diameter of ST during orthodontic treatment planning, diagnosis of pathology of the pituitary gland, and age determination

Phytochemical Screening and Antioxidant Activity of Balanites Aegyptiaca Root Bark Extracts: Influence of solvent

Communication in Physical Sciences 2020, 5(2):156-164 Author: A. Usman, Y. Mohammed, H. O. Muhammed, N. L. Usman and A. H. Zakari Received 24 April 2020/Accepted xx xx xxxx 2020 Balanites aegyptiaca (L) Del is a medicinal plant used in Africa’s folk medicines to treat wide range of diseases. Phytochemical screening of aqueous and ethanolic extracts of Balanites aegyptiaca (L) Del root indicated the presence of flavonoids, saponins, tannins and phenols.The ethanolic extract of the plant root had in addition carbohydrate, cardiac glycoside and steroids while n-hexane extract indicated the presence of anthraquinone, carbohydrates, cardiac glycoside, terpenoids and resins. The extracts were also evaluated for their free radical scavenging potential, total phenolic and total flavonoid contents. The antioxidant activity was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, the total phenolic content was evaluated using Folin-Ciocalteau assay, while the total flavonoid content was assessed by the aluminium chloride colorimetric assay. The results obtained revealed that the ethanolic extract exhibited higher total antioxidant capacity in the range of 55.23±0.4 to 81.04±0.9% while concentrations in the aqueous extract ranged from 20.15±0.2 to 35.11±0.2% compared to 80 % of standard ascorbic acids. Estimated total phenolic content in aqueous and ethanolic extracts were 179.48±1.99 and 260.07±2.31 mg/gallic acid equivalent (GAE)/g respectively. However, the total flavonoid content for aquoues and ethanolic extracts were 69.17±0.32 and 95.52±0.41 mg/ quercetin equivalent (QE)/g respectively. Total phenol and flavonoid were absent in normal hexane extract. The results obtained from the study indicated that the choice of solvent can influence the components that can be extracted from Balanites aegyptiaca (L) Del root and that for optimum extracts to be obtained, the best solvent is ethanol

ARTIFICIAL NEURAL NETWORK PREDICTION OF PERFORMANCE CHARACTERISTICS OF BIOFUEL PRODUCED FROM SWEET POTATOE (IPOMOEA BATATA)

Fossil fuel depletion and the harm it causes to the environment has led to the development of alternative fuels. In this research, biofuel (ethanol) was produced and characterized from sweat potatoes. Blends of premium motor spirit with 0% (E0), 2% (E2), 4% (E4), and 10% (E10) of the produced biofuel at various percentages were separately used to power a four-stroke, single-cylinder SI engine on an engine test bed, and data of the engine performance - brake power, brake torque, brake mean effective pressure (BMEP), and the exhaust gas temperature reported in each test. The results of the physicochemical analysis revealed that the physical state of the biofuel is colorless, the viscosity at 300C, density, calorific value, and pH level are 0.9834 mPa.s, 0.85 g/cm3,19 kJ/kg, and 1.82, respectively. It was observed that an increase in ethanol in the blend increases the performance of the engine, although the BMEP at E0 gave the highest value of 0.3 bar compared to other blends.  An artificial neural network (ANN) model for predicting engine performance characteristics was developed, trained, validated, and tested using the reported data. The result of the ANN model revealed that the Levenberg-Marquardt training algorithm (LMTA) with 10 hidden layer neurons offers the best fit for the features for both training, validation, testing, and overall. With the R for training equal 1, validation equal to  0.99468, testing equal to 0.90103, and overall R equal to  0.93842 as compared to the rest in terms of the number of neurons and training algorithms.

Impact of Microwave Irradiation Energy Levels on Molecular Rotation, Structural, Physicochemical, Proximate and Functional Properties of Potato (Ipomoea batatas) Starch

Starch isolated from potato was subjected to microwave treatment at different energy levels (200 - 800 W) to modify the functional, structural and physicochemical properties, as well as induce molecular rotation of the hydroxyl group on the starch polysaccharide. Proximate analyses revealed that moisture content reduced, while ash, protein, fat and fibre increased after modification. Fourier-transform infrared spectroscopy spectra indicated a strong shift in absorption band of OH from 3441 to 3454 cm-1. Optical light microscopy revealed that starch granules were oval and spherical in shape with hyla on some of the granules. Least gelation concentration reduced following microwave treatment. Compared with the native starch, the pasting parameters of the microwave treated starches decreased, with the exception of set­back viscosity for starch modified at 800 W. Onset temperature (TO), peak temperature (TP) and conclusion temperature (TC) of gelatinization increased in microwave treated starches compared with native potato starch. Also, gelatinization enthalpy increased from 8.21 J/g in native starch to 15.39, 16.36, 17.76 and 38.06 J/g in microwave treated starches at 200, 400, 600, and 800 W, respectively. It was concluded that the energy of microwave irradiation can induce and accelerate molecular rotation of the hydroxyl group on the starch polysaccharide

On the selection and design of proteins and peptide derivatives for the production of photoluminescent, red-emitting gold quantum clusters

Novel pathways of the synthesis of photoluminescent gold quantum clusters (AuQCs) using biomolecules as reactants provide biocompatible products for biological imaging techniques. In order to rationalize the rules for the preparation of red-emitting AuQCs in aqueous phase using proteins or peptides, the role of different organic structural units was investigated. Three systems were studied: proteins, peptides, and amino acid mixtures, respectively. We have found that cysteine and tyrosine are indispensable residues. The SH/S-S ratio in a single molecule is not a critical factor in the synthesis, but on the other hand, the stoichiometry of cysteine residues and the gold precursor is crucial. These observations indicate the importance of proper chemical behavior of all species in a wide size range extending from the atomic distances (in the AuI-S semi ring) to nanometer distances covering the larger sizes of proteins assuring the hierarchical structure of the whole self-assembled system

Pan-Arctic Fisheries and their Assessment

Pan-Arctic fisheries are highly diverse in their purpose, species biology, productivity, economic and strategic importance as well as in how they are prosecuted. They range from full industrial fisheries to community-based artisanal, sport and subsistence fisheries. The nature of Arctic ecosystems in the region varies from extremely productive to relatively barren in terms of fisheries production. Gear types vary, but offshore trawl fisheries and inshore and freshwater gillnet fisheries are the most common. Rights-based fisheries (e.g., for indigenous inhabitants) are more prominent in the Canadian and American Arctic than in European jurisdictions. The principal harvested species in freshwater environments tend to be from few taxa mainly Salvelinus spp. and from the family Coregonidae, while the marine taxa are more diverse. Compared to north temperate fisheries, Arctic fisheries have impressive variation across longitudes; some jurisdictions support only small-scale subsistence fisheries, whereas others contain some of the largest yields among industrial fisheries. Approaches to scientific assessment are also highly diverse with a range from catch-based indicators to sophisticated fully age-structured population models

Synthesis and characterization of a tetranuclear Cu(II) coordination polymer containing pyridine-2,6-dicarboxylic acid and 4-amidinopyridine co-ligand

This research demonstrates the preparation of a new coordination polymer, {[Cu4(H2pydc)2(H1apy)(H2O)2DMF].DMF}n, (H2pydc = pyridine-2,6-dicarboxylic acid, H1apy = 4-amidinopyridine) under solvothermal condition by the self-assembly of pyridine-2,6-dicarboxylic acid, 4-midinopyridene and copper(II) acetate. The compound was characterized by elemental analysis and infrared spectroscopic technique. The analysis indicated that the 4-amidinopyridine coordinated to the copper ions through the terminal nitrogen in a monodentate fashion while the pyridine-2,6-dicarboxylic acids coordinated through the carboxylate oxygens in monodentate mode. Both the elemental analysis and the infrared spectroscopic data agreed with the proposed stoichiometry. This result represent the first report of a tetranuclear Cu(II) coordination polymer having coordinated 4-amidinopyridine as the nitrogen donor moiety in its structure

Recent advances of data compression in wireless sensor network

Wireless Sensor Networks (WSNs) have emerged as one of the most promising wireless communication systems supporting wide variety of applications ranging from military tasks, healthcare, disaster prediction and indoor positioning. The low complexity and cost of the nodes result in constraints such as computational power, communication bandwidth and battery power. Energy consumption is one of the most critical to WSN. In WSN communication, data transmission is considered the largest contributor to total energy exhaustion and apparently, it is influenced by the size of the data. Favorably, data compression can be used to reduce the amount of data that requires to be transmitted and hence prolongs sensor's lifetime. In this study, we survey various approaches, issues and challenges to WSN efficiency related to data compression discuss the effect of the data size on the sensor efficiency and how data compression algorithms can be used to address small size data transmission. Finally, recent approaches are reviewed with highlighting of advantages and disadvantages of each solution