QScience Connect - Volume 2013, Issue 1

Polyvinyl alcohol (PVA)/Na-rich Montmorillonite (MMT) nanocomposites were prepared using solution method to create polymer-clay nanocomposite (PCN) material. The PCN material was studied using X-ray diffraction (XRD), demonstrating polymer-clay intercalation that has a high d-spacing (lower diffraction angles) in the PCN XRD pattern, compared to the pure MMT clay XRD pattern, which has a low d-spacing (high diffraction angles). The nano-scanning electron microscope (NSEM) was used to study the morphological image of the PVA, MMT and PCN materials. The results showed that intercalation that took place between the PVA and MMT produced the PCN material.

The mechanical properties of the pure PVA and the intercalated polymer material were studied. It was found that the small amount of MMT clay made the tensile modulus and percentage of the total elongation of the nano-composite significantly higher than the pure PVA polymer value, due to polymer-clay intercalation. The thermal stability of the intercalated polymer has been studied using thermal analytical techniques such as thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results showed that the PCN material is more thermally stable than the pure PVA polymer.

We realize noncommutative phase spaces as coadjoint orbits of extensions of the Aristotle group in a two-dimensional space. Through these constructions the momenta of the phase spaces do not commute due to the presence of a naturally introduced magnetic field. These cases correspond to the minimal coupling of the momentum with a magnetic potential.

The anisotropy factor as a function of fiber arrangement, fiber fineness and sample thickness has been derived from the theories of soundwave transformation due to phase changing. The sound absorption coefficient of the anisotropic fibrous material is then theoretically calculated. The fibrous materials were prepared so that the fibers are arranged parallel (perpendicularly laid fiber web called STRUTO technology) in the direction of soundwave propagation or perpendicularly (longitudinally laid fiber web) to the direction of sound propagation. The sound absorption coefficient was measured due to the Impedance tube. The theoretical results are in good agreement with experimental findings.

Harnessing waste energy from the manmade air fields of buildings presents a new area of renewable energy to explore. Due to the unpredictability of the natural wind, this study is to evaluate the practicality for harnessing waste energy from the air conditioner exhaust units which are a more constant and predictable source available in the buildings. A prototype of the micro wind turbine has been designed to minimize the negative effect of the exhaust sources. After the micro wind turbine was manufactured, the performance of the turbine was tested in the selected air conditioner exhaust unit. Increasing the rotor solidity and decreasing the resistance of the generator contribute to improved starting torque and decreased generator break in torque respectively in the design. The power generation of the micro wind turbine increases with an increase of the rotor speed. The 24-hour operation of the prototype presents an observation for both exhaust performance and power generation prediction when the prototype is mounted on the exhaust unit.

The distribution and localization of serotonin immunoreactive cells in the superior colliculus of the porcupine (Hystrix cristata) was studied using the peroxidase-antiperoxidase method and an antiserum against serotonin. The study was performed on four superior colliculus' of porcupine. Serotonin immunoreactivity showed a dense body of positively labelled cells throughout the superior colliculus. These serotonin immunoreactive cells had a characteristic arrangement corresponding to the laminar structures of the superior colliculus. In this study, the densest concentration of serotonin immunoreactive cells was found in a single tier located within the stratum zonale (SZ) and upper part of the stratum griseum superficiale (SGS). The second densest is located within stratum griseum intermedium (SGI) and the third appears as an incomplete layer, found only in the medial and central parts of the stratum griseum profundum (SGP). On the basis of these findings, serotonin has been suggested to be an inhibitory neurotransmitter and neuromodulator in the mammalian superior colliculus.

Background: Attempts to produce greener bromination of 2-acetyl 9H-fluorene with KBr+KBrO3 reagent using fly-ash:H2O catalyst in aqueous media gave 9H-fluorenacylbromides. Generally, the halo-keto compounds possess insect antifeedant activities. Therefore, the insect antifeedant activities of these acyl bromides have been studied using 4^th instar larvae Achoea janataL against castor semilooper. Methods: Solvent free bromination method was used for synthesizing some 9H-fluorenacylbromides. They were characterized by UV, IR, NMR and mass spectroscopic data. Castor-leaf discs were used for evaluation of insect antifeedant activities of the synthesized acyl bromides. Results: The yields of synthesized acyl bromides were over 60%. The physical constants, analytical and spectral data of these ketones has been determined. Halo substituted acyl bromides gave good insect antifeedant activities. Conclusion: Easy handling, non-hazardous and environmentally benign bromination methods have been adopted for synthesizing acyl bromides with good yields. Bromo substituted acyl bromides show better insect antifeedant activity.

Background: The aim of this study was to synthesise some substituted styryl 3,4-dimethoxy phenyl ketones using solvent-free SiO2–H2SO4 catalyzed aldol condensation between 3,4-dimethoxy acetophenone and substituted benzaldehydes under microwave irradiation. Then to characterize them by their analytical, physical and spectroscopic data, and also to study their the spectral correlation and antimicrobial activities. Methods: Solvent free microwave assisted aldol condensation method was used for synthesising 3,4-dimethoxyphenyl chalcones. They were characterised by ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR) and mass spectroscopic data. The UV, IR, NMR spectral data were correlated with substituent constants, F and R parameters, using Hammett equation, to study the effect of substituents. The Bauer-Kirby method was used for evaluation of antimicrobial activities of the synthesised chalcones. Results: Yields of synthesised chalcones were more than 85%. The spectral data of these ketones had been correlated, using single and multi-linear regression analysis. These gave a satisfactory degree of correlations with some parameters and a fair degree of correlations with other parameters. Few chalcones gave excellent antimicrobial activities, whereas others gave poor antimicrobial activities. Conclusion Easy handling, non-hazardous and environmentally benign aldol condensation method had been adopted for synthesising chalcones with better yields. Some of the Hammett spectral correlations were found to be satisfactory with the observed spectroscopic data. Halo, methoxy, methyl and nitro substituted compounds had shown excellent antimicrobial activities based on their zone of inhibitions.

The aim of this work was to study the effect of friction time on the microstructure and mechanical properties of alumina 0, 25, 50 wt% yttria stabilized zirconia (YSZ) composite and 6061 aluminium alloy joints formed by friction welding. The alumina-YSZ composites were prepared through slip casting in plaster of Paris molds (POP) and subsequently sintered at 1600°C, while the aluminium rods were machined down using a lathe machine to the dimension required. The welding process was carried out under different rotational speeds and friction times, while friction force (0.5 ton-force) was kept constant. Scanning electron microscopy was used to characterize the interface of the joints structure. The experimental results showed that the friction time has a significant effect on joint structure and mechanical properties.

Background: Depression and obesity are common disorders. Obesity is also predictive of several chronic diseases like hypertension and diabetes. The aim of this study was to evaluate and compare depression frequency of obese patients with hypertension or diabetes. Methods: Weight, height and body mass index (BMI) were measured. The definition of obesity was a body mass index (weight (kg)/height (m)²) ≥ 30 kg/m². Obese patients with hypertension or diabetes were documented. All participants had a Beck Depression Inventory (BDI) evaluation. Results: A total of 389 subjects were included, of whom 100, 101, 92, 96 participants were healthy, obese, obese with hypertension, obese with diabetes, respectively. Beck Depression Inventory scores of obese patients, obese patients with hypertension or diabetes were higher compared to the control group. BDI scores of obese patients with diabetes were higher compared to obese and obese with hypertension subjects. Conclusions: Obesity is a risk for depression and other chronic diseases. Obesity can increase depressive symptoms. The level of depressive symptoms in obese patients varied according to chronic disease type. In the present study, diabetes appears to be more closely related to depression than hypertension.

Trial registry: ANEAH.EK. 25.11.2010.47

With the significant rise in hospital infection management in dental hospitals as well as in hospitals, and in order to identify the distribution of pathogenic bacteria on hands and nasal cavity of workers in a dental hospital, bacteria from the hands and nasal cavities of six dentists and 44 dental hygienists from four dental hospitals were investigated. The results showed Staphylococcus aureus, Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus warneri, Staphylococcus xylosus, Staphylococcus. Lugdunensis, and Neisseria spp., were isolated from the nasal cavity and Staphylococcus aureus, Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus warneri, Staphylococcus xylosus, Staphylococcus leutus, Micrococcus spp., Staphylococcus cohnii, Serratia marcescens, Pseudomonas aeruginosa, Klebsiella pneumonia and Pseudomonas pneumotropica from the hands. An antimicrobial disk diffusion test was conducted on Staphylococcus aureus isolated from the hands and nasal cavity to detect MRSA by means of oxacillin. Two strains were detected. When the genes of penicillin binding protein 2 (mecA) were detected from the 2 strains, MRSA was found from both strains. The results of this investigation on the distribution of various pathogenic bacteria and MRSA on hands and nasal cavity of workers of a dental hospital, will contribute to the basic data for the future infection management in a dental hospital.

Intrahepatic cholangiocarcinomas are rare, aggressive tumours. We discuss an afflicted patient who had relatively larger thrombi disseminated into the right atrium. A 63-year-old female patient with intrahepatic cholangiocarcinoma referred with complaints of swellings on her face, upper half of her body, and both arms. On contrast-enhanced thoracic CT scans and transthoracic echocardiograms of the patient an intraluminal thrombus measuring 36.3 × 25.7 mm extending to the orifice of the right atrium was seen. Thrombolytics were not successful in reducing the dimensions of the thrombus.

Medicinal plants play an important role in human livelihoods. However, the harvest of different organs may be destructive. Sarcocephalus latifolius is a species whose roots are harvested for medicinal purposes. This study was carried out to assess the root characteristics, biomass yield and morphological variations within different habitats of southern Benin. Forty-eight S. latifolius individual plants were randomly selected in three localities, representing four habitats for the species. Information collected was related to height, basal diameter, diameter at breast height, number, depth of insertion and the length and the diameter of the roots. Observations were also made on organ characteristics to identify morphologic variation. The study showed that the optimum development of the root system is established in fallow ground and savannas. The species presents two morphotypes at the stem and root levels. Root biomass varied according to the developmental stage and habitat. A model of root biomass estimation was established and can be used to determine the root biomass within habitats. Across habitat, the number of roots is the major determinant for root biomass yield. Therefore, harvest should take into consideration habitat and the developmental stage according to the use type.

In this paper, a simulation optimization-based decision support tool has been developed to study the capacity enhancement scenarios in a tire manufacturing company located in Iran. This company is experiencing challenges in synchronizing production output with customer demand causing an unbalanced work-in-process (WIP) inventory distribution throughout the tire manufacturing process. However, a new opportunity to increase the supplying of raw materials by fifty percent and increase the expected growth in market demand, necessitate this study of the current company situation. This research supported by the company, is to analyze whether the ongoing production logistics system can respond to the increased market demand, considering the raw material expansion. Implementation of a proposed hybrid push/pull production control strategy, together with the facility capacity enhancement options in bottleneck stations and/or heterogeneous lines within the plant, are investigated by the proposed simulation optimization methodology.

This article is an introduction to a new approach to first principles electronic structure calculation. The starting point is the Hartree-Fock-Roothaan equation, in which molecular integrals are approximated by polynomials by way of Taylor expansion with respect to atomic coordinates and other variables. It leads to a set of polynomial equations whose solutions are eigenstate, which is designated as algebraic molecular orbital equation. Symbolic computation, especially, Gröbner bases theory, enables us to rewrite the polynomial equations into more trimmed and tractable forms with identical roots, from which we can unravel the relationship between physical parameters (wave function, atomic coordinates, and others) and numerically evaluate them one by one in order. Furthermore, this method is a unified way to solve the electronic structure calculation, the optimization of physical parameters, and the inverse problem as a forward problem.

Background: The frequent co-abuse of alcohol and tobacco may suggest that they share some common neurological mechanisms. For example, nicotine acts on Nicotinic acetylcholine receptors (nAChRs) in the brain to release dopamine to sustain addiction. Might nAChRs be entwined with alcohol? Objectives: This review summarizes recent studies on the relationship between alcohol and nAChRs, including the role of nAChRs in molecular biological studies, genetic studies and pharmacological studies on alcohol, which indicate that nAChRs have been potently modulated by alcohol. Methods: We performed a cross-referenced literature search on biological, genetic and pharmacological studies of alcohol and nAChRs. Results: Molecular biological and genetic studies indicated that nAChR (genes) may be important in mediating alcohol intake, but we still lack substantial evidence about how it works. Pharmacological studies proved the correlation between nAChRs and alcohol intake, and the association between nicotine and alcohol at the nAChRs. The positive findings of varenicline (a partial agonist at the α4β2 nAChR, smoking-cessation pharmaceutical) treatment for alcoholism, provides a new insight for treating co-abuse of these two substances. Conclusions: Molecular biological, genetic and pharmacological studies of alcohol at the nAChR level, provide a new sight for preventing and treating the co-abuse of alcohol and nicotine. Given the important role of nAChRs in nicotine dependence, the interaction between alcohol and nAChRs would provide a new insight in finding effective pharmacological treatments, in decreasing or stopping alcohol consumption and cigarette smoking concurrently.

Background: Unwanted hair is one of the most common medical problems affecting women of reproductive age inducing a lot of psychological stress and threatening their femininity and self-esteem. Old methods of removing unwanted hair include shaving, waxing, chemical depilation, and electrolysis, all of which have temporary results. However laser-assisted hair removal is the most efficient method of long-term hair removal currently available. It is desirable to develop a reduced cost photodynamic therapy (PDT) system whose properties should include high efficiency and low side-effects. Method: Mice skin tissues were used in this study and divided into six groups such as controls, free methylene blue (MB) incubation, liposome methylene blue (MB) incubation, laser without methylene blue (MB), free methylene blue (MB) for 3 and 4 h and laser, liposome methylene blue (MB) for 3 h and laser. Methylene blue (MB) was applied to wax epilated areas. The areas were irradiated with CW He-Ne laser system that emits orange-red light with wavelength 632.8 nm and 10 mW at energy density of 5 J/cm² for 10 min. The UV-visible absorption spectrum was collected by Cary spectrophotometer. Results: Methylene blue (MB) is selectively absorbed by actively growing hair follicles due to its cationic property. Methylene blue (MB) untreated sections showed that hair follicle and sebaceous gland are intact and there is no change due to the laser exposure. Free methylene blue (MB) sections incubated for 3 h showed that He:Ne laser induced destruction in hair follicles, leaving an intact epidermis. Treated section with free methylene blue (MB) for 4 h showed degeneration and necrosis in hair follicle, leaving an intact epidermis. Liposomal methylene blue (MB) sections incubated for 3 h showed He:Ne laser induced destruction in hair follicles with intradermal leucocytic infiltration. Conclusion: Low power CW He:Ne laser and methylene blue (MB) offered a successful PDT system in selectively damaging hair follicles, leaving an intact epidermis. The current PDT system provides better outcome than hair destruction through laser heat transfer procedures and laser-mediated hair removal, due to complete destruction of hair follicles.

Background: Hepatic fibrosis results from an imbalance between fibrogenesis and fibrolysis in the liver. The process of Ito cell activation, which is thought to be the central pathogenic mechanism in liver fibrogenesis/cirrhosis, may involve distinct interactions with Kupffer cells (KCs) mediated by various cytokines and growth factors. The aim of this study was to determine whether targeting KC function using GdCl3, which specifically acts on Kupffer cells, interferes with the manifastation of carbon tetrachloride (CCl4) and dimethylnitrosamine (DMN) induced hepatic fibrosis/cirrhosis. Methods: We assesed the change in distribution of ECM proteins, laminin and fibronectin and the marker of HSC activation, alpha-smooth muscle actin (α-SMA) after liver injury and after KC inactivator, GdCl3-treatment with light microscope immunohistochemistry. Using light microscopy, characteristic changes of fibrosis/cirrhosis were seen in the hepatotoxin-administrated groups. Results: The immunohistochemical profile of anti-laminin was significantly altered in hepototoxin-treated groups (p < 0.05) and GdCl3 blocked this effect. The immunoproducts of anti-fibronectin and anti-SMA antibody were not significantly altered in the CCl4-treated group. In contrast, after DMN-induced flbrosis/cirrhosis, laminin, fibronectin and α-SMA staining were significantly increased (p < 0.05) and were present along the sinusoids in cirrhotic liver tissue. However, those ECM proteins and α-SMA staining in the parenchyma and fibrotic nodules decreased but not significantly after GdCl3 treatment. Conclusions: The results suggest that GdCl3 suppressed the activation of lipocytes and their transition from hepatic lipocytes to myofibroblast-like cells in cirrhotic livers in CCl4-treated mice. These results support that treatment with the selective Kupffer cell toxicant GdCl3 prevents stellate cell activation and prevents liver fibrosis/cirrhosis

Background: This study aims to synthesise a series of 1-thiocarbomyl pyrazolines, including 3-(3,4-dibromophenyl)-5-(substituted phenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamides, using solvent-free fly-ash:PTS catalyzed cyclization between chalcones and thiosemicarbazide, under microwave irradiation. Then to characterize them using analytical, physical and spectroscopic data.

Methods: Solvent-free microwave assisted cyclization was adopted for the synthesis of 1-thiocarbomyl, including 3-(3,4-dibromophenyl)-5-(substituted phenyl)-4,5-dihydro-1H- pyrazole-1-carbothioamides, using fly-ash:PTS as the catalyst. They were characterised by IR, NMR and mass spectroscopic data. The infrared (IR) and nuclear magnetic resonance (NMR) spectral data was correlated with substituent constants, F and R parameters, using Hammett equation, to study the effect of substituents.

Results: The yields of the synthesised chalcones were more than 85%. The spectral data of these 3-(3,4-dibromophenyl)-5-(substituted phenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamides had been correlated, using single and multi-linear regression analysis. These gave a satisfactory or fair degree of correlation with some parameters.

Conclusion: Easy handling, non-hazardous and environmentally benign cyclization method had been adopted for the synthesis of 1-thiocarbomyl pyrazolines using fly-ash:PTS as catalyst, with better yields. Some of the Hammett spectral correlations were found to be satisfactory, with the observed spectroscopic data.

This paper shows the combination of an efficient transformation and Exp-function method, to construct generalized solitary wave solutions of the nonlinear Burger's equations of fractional-order. Computational work and subsequent numerical results re-confirm the efficiency of the proposed algorithm. It is observed that the suggested scheme is highly reliable and may be extended to other nonlinear differential equations of fractional order.

We report the discovery of the blister beetle, Meloe coelatus Reiche, 1957, in Qatar. According to the Catalogue of Palaearctic Coleoptera there is no record for the genus Meloe in Qatar, although the genus is well represented in other areas of the Arabian Peninsula. M. coelatus is a rare species, that is present along a wide area of Northern Africa and Western Asia. Our findings bridge the current geographic gap in the known distribution of the species from Saudi Arabia to Iran. We believe the Coleoptera fauna of Qatar might be underestimated. A thorough field survey is recommended in order to document the presence of other species of this family, and also to complete the catalogue of Coleoptera for the State of Qatar.

In this paper an inhomogeneous beam with a damping distributed along the length is considered. The beam is clamped at both ends and is assumed to vibrate in a transverse direction only. The total energy of the system at any time t is estimated. Finally, an explicit form of exponential energy decay is obtained. Hence, the uniform stabilization of the system is achieved.

Background: The demography of Copts in Egypt is subject to an intense debate in the context of a dearth of analytical studies on this community. Our objective was to estimate the size of the Coptic community in Egypt, map its geographical clustering, and describe demographic, socioeconomic, and health-associated indicators. Methods: We conducted descriptive and Kulldorff spatial scan statistics analyses using the 2008 Egypt Demographic and Health Survey (EDHS) data. We also used chi-square trend analysis and earlier EDHS data to examine the temporal trend in the proportion of Copts. Results: The proportion of Copts in the 15–59 years population was 5.1% (95% confidence interval (CI): 4.6%–5.5%). This translates to 4,274,145 (95% CI: 3,855,111–4,609,372) Copts. We identified three main clusters of Copts: Minya-Assuit cluster (17.6%), Assuit-Souhag cluster (15.1%) and the metropolitan Cairo cluster (9.4%). The proportion of Copts was stable since 1988 (P = 0.11). Copts had higher educational attainment (P = 0.002), and a wealth index quintiles distribution skewed towards the rich (P < 0.001). Copts also had stronger representation in white collar job types, but limited representation in security agencies. The majority of demographic, socioeconomic and health indicators were similar among Copts and Muslims. Conclusions: One in every 20 Egyptians is a Copt, a proportion smaller than commonly circulated in the scholarly literature and public sphere. Despite some identified disparities, our study indicates a well-integrated Egyptian society regardless of religious affiliation. Our study provides evidence to inform the ongoing debate on the status of Copts in Egypt.

In this paper, the differential equation of a vertically falling non-spherical particle in incompressible Newtonian media is solved by homotopy analysis method (HAM). The results are analyzed using graphs and comparison tables.

The (G′/G, 1/G)-expansion method is one of the most direct and effective methods for obtaining exact traveling wave solutions of nonlinear partial differential equations (PDEs). In this paper, we construct exact travelling wave solutions of nonlinear evolution equations in mathematical physics via generalized Zakharov-Kuznetsov (ZK), modified Zakharov-Kuznetsov and Sharma–Tasso–Olver (STO) equations by (G′/G, 1/G)-expansion method, where satisfies the auxiliary ordinary differential equation (ODE) ; λ and μ are arbitrary constants.

As part of the biodiversity surveys conducted by the Department of Biodiversity at the Qatar Environment and Energy Research Institute (QEERI), we can report the presence of Scaurus puncticollis Solier, 1838 in Qatar, and confirm the first record for the tribe Scaurini Billberg, 1820 in the country. We found two living specimens and remains of a third one distributed over the year (February, April and October) in three different locations of the Al Rayyan Municipality in Qatar. These findings reveal that the fauna of darkling beetles of Qatar is, despite previous efforts, still underestimated. To document and report the actual Biodiversity Heritage of Qatar, new exhaustive field biodiversity surveys should be conducted to complete the catalogue of Tenebrionoidae for the State of Qatar.

We present a geometric argument that explains why some systems having vanishing largest Lyapunov exponent have underlying dynamic aspects which can be effectively described by the Tsallis entropy. We rely on a comparison of the generalised additivity of the Tsallis entropy versus the ordinary additivity of the BGS entropy. We translate this comparison, in metric terms, by using an effective hyperbolic metric on the configuration/phase space for the Tsallis entropy versus the Euclidean one in the case of the BGS entropy. Solving the Jacobi equation for such hyperbolic metrics effectively sets the largest Lyapunov exponent computed, with respect to the corresponding Euclidean metric, to zero. This conclusion is in agreement with all currently known results on systems that have a simple asymptotic behaviour, and are described by the Tsallis entropy.

The equations of generalized thermoelastic diffusion with four relaxation times are given. The variational principle is derived. Using Laplace transforms, a uniqueness theorem for these equations is proved. Also, a reciprocity theorem is obtained.

We report the discovery of a gecko species, the Persian leaf-toed gecko Hemidactylus persicus Anderson, 1872 (Gekkonidae) in Qatar, found on Halul Island. According to the Qatar National Biodiversity Surveys and the available international literature H. persicus was not previously recorded in Qatar. Its known range covers the north east of the Arabian Peninsula, Bahrain, the United Arab Emirates, and south western Asia. Our findings bridge the current geographic gap in the known distribution of the species from Saudi Arabia to Asia. We believe that the species could also be present in the Qatar peninsula. A thorough field survey is needed in order to map the range of this species in the State of Qatar.

Ground Granulated Blast Furnace Slag (GGBFS) is a byproduct in the manufacture of pig iron, which contains almost the same chemical compositions as cement. As a new method for activation of GGBFS, a simple sonochemical route was developed to synthesize nanoparticles of GGBFS. Chemical composition of the GGBFS sample was characterized using X-ray fluorescence (XRF). Crystallinity, morphology and reactivity of the GGBFS samples were compared before and after the sonochemical process, by using Powder X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Thermal Gravimetry and Differential Thermal Analysis (TG/DTA). Based on the DTG results, Nano GGBFS showed a superior reactivity compared with the bulk form. Therefore, sonochemistry is an appropriate method for the activation of cement additives.

Background: This study aimed to synthesize some 2′, 3′, 4′-trichlorophenyl chalcones [(E)-1-(2, 3, 4-trichlorophenyl)-3-(substituted phenyl)-2-propen-1-ones] using solvent-free sulfated Titania catalyzed aldol condensation between 2, 3, 4-trichloroacetophenone and substituted benzaldehydes under microwave irradiation. To characterize these chalcones using analytical, physical and spectroscopic data and also to study their the spectral correlation and antimicrobial activities. Methods: Solvent free microwave assisted aldol condensation method was used for synthesizing substituted styryl 2′, 3′, 4′-trichlorophenyl ketones. They were characterized by UV, IR, NMR and mass spectroscopic data. The UV, IR, NMR spectral data were correlated with substituent constants, F and R parameters, using Hammett equation, to study the effect of substituents. The Bauer-Kirby method was used for the evaluation of antimicrobial activities of the synthesized chalcones. Results: The yields of the synthesized chalcones were more than 90%. The spectral data of these ketones had been correlated, using single and multi-linear regression analysis. These gave a satisfactory degree of correlations with some parameters and a fair degree of correlations with some parameters. Few chalcones had excellent antimicrobial activities, whereas, others showed poor antimicrobial activities. Conclusion: Easy work-up and handling, non-hazardous and environmentally benign aldol condensation method had been adopted for synthesizing chalcones with better yields. Some of the Hammett spectral correlations were found satisfactory with the observed spectroscopic data. Halo, methoxy, methyl and nitro substituted compounds had shown excellent antimicrobial activities based on their zone of inhibitions.

This study examines the environmental factors affecting the density of the exploited giant land snail species, Archachatina marginata, Achatina fulica and Limicolaria flammea in the Dassa-Zoumè district of Benin. Thirty plots of 30 m × 30 m were laid out, within four vegetation types (fallows, forest, woodlands and wood savannah). Inside each plot the numbers of each giant land snail species were counted, and soil characteristics were measured. ANOVA and generalized linear models (GLMs) with Poisson distribution were used to examine the influence of soil factors on the giant land snails. A. fulica has the highest mean density (507 snails/ha) while A. marginata has the lowest density (110 snails/ha). ANOVA showed no significant difference in density between habitat types for any species. The most parsimonious GLM model showed that the abundance of A. fulica was positively associated to the fine sands, fine silts and pH, while the interactions were negatively associated with the abundance of the species. The abundance of L. flammea was negatively associated with the fine sands, fine silts and pH, while the interactions were positively associated with the abundance of the species. As for A. marginata, the abundance was negatively associated with the fine silts, pH and litter, while the interactions were positively associated with the abundance of the species. The abundance pattern of forest molluscs is likely to be affected by different processes. Exploitation of these giant snails will affect their density, and further research is needed to establish appropriate levels of harvesting and habitat management.

Effect of thermal conductivity on gravitational instability of quantum plasma in the presence of fine dust particles has been investigated. Following the linearized stability theory and normal mode analysis, the paper established a general dispersion relation of the problem. Modified condition of Jeans gravitational instability is obtained due to quantum effect. Numerical calculations were performed to find the effect of each parameter on the growth rate of instability. The effect of fine dust particles does not affect the instability condition of the system but stabilizes the system by decreasing the growth rate of unstable mode. Curves show the destabilizing effect of thermal conductivity and stabilizing effect of quantum correction on the growth rate of unstable mode. The stability of the system is discussed by Routh-Hurwitz criterion of stability.

This paper describes the optical limiting performance of 2D ZnO nanoflakes and plates synthesized through a simple wet chemical method. Scanning electron microscopic imaging of these nanostructures revealed the shape evolution from the nanoflakes to nanoplates as the growth duration increased from 11 h to 18 h. The nonlinear absorption is studied using open aperture Z scan technique. The process behind the nonlinear absorption is predicted as two photon absorption and one photon assisted energy transfer to the nearby trapping sites. We observe the appreciable optical limiting threshold of 46.86 MW/cm² for high pump power of 436 MW/cm² for nanoplates compared with nanoflakes (169.49 MW/cm²).

The Gulf sand gecko (Pseudoceramodactylus khobarensis Haas, 1957) is a nocturnal gecko endemic to the Arabian Gulf countries. In this study we report the presence of this species in Qatar for the first time. Our findings bridge one of the current geographic gaps in the known distribution range of this species. In Qatar, the species has been found on the mainland and on two islands occupying coastal salty habitats with shrubs. The islands are the smallest where this species is known to occur. We believe that this gecko species is more widely distributed in Qatar than we report here and that an extensive inventory is required to map the full range of the species in Qatar and also in other countries of the Arabian Gulf.

By integrating Radio Frequency Identification (RFID) technology with Wireless Sensor Networks (WSN), it is feasible to route RFID data from readers and RFID enhanced wireless sensor nodes (WSN) into base-stations through existing WSN clustering protocols. WSNs for reducing energy consumption and improving stability period can use clustering algorithms. Clustering sensor nodes are a useful topology control technique, but these algorithms are not always suitable for heterogeneous WSNs. Previous constructive algorithms, such as LEACH and SEP are not always stable in heterogeneous WSNs. They are designed without regard to appropriate parameters, such as remaining power and confidence value of the nodes for WSNs. In this paper we suggest and introduce a novel stable heterogeneous cluster-based protocol with cluster member bounds for heterogeneous RFID enhanced WSNs, which called SHCP. In SHCP, the probability of cluster-heads (CHs) election are weighted by the primary energy of a node relative to that of other nodes in the network and cluster formation, based on nodes current energy, numbers of current members which belong to a CH, distance between CHs and nodes and distance between CHs and base-station. Our conclusion shows the simulation results show SHCP achieves longer stability time until the first node dies (FND), half nodes die (HND) and improves energy utilization in WSNs.

A characteristic property of esters is that, they undergo both oxidation and hydrolysis under similar conditions. Furthermore, the product of each process is an aldehyde (the product of hydrolysis is alcohol, which in turn undergoes oxidation to give an aldehyde). It is, therefore, difficult to find out which process is operative. The kinetics of the reaction offers an opportunity to resolve this uncertainty. This method is illustrated in this article with two examples: oxidation of esters by Tl³⁺ and oxidation of esters by Co³⁺. The method described in this paper familiarizes students with the basic techniques involved in following the reaction, such as quenching the reaction, ensuring that the aliquots of reaction mixture are equal, taking the reaction mixture at all time intervals in an identical manner, taking infinite readings and the use of a thermostat. It also provides familiarity with the use of integrated rate equation, plotting graphs, the evaluation of slopes on graphs and the calculation of rate constants.

Minerals have a profound impact on reproduction. The relations between estradiol-17β (E2) and blood mineral levels have been studied mainly in human and rats, but not in quail. Therefore, the aim of this study was to test the effect of E2 on serum mineral concentrations in Japanese quail (Coturnix japonica). The study was conducted at the Seljuk University animal farm thirteen week old female Japanese quails (n = 33) were housed in cages (25 × 35 × 48 cm) under a 16 hours light: 8 hours dark cycle. During the course of the study, birds were fed ad libitum with a diet supplying 20% crude protein, 2901 kcal/kg metabolic energy, 2.5% calcium (Ca), 0.35% phosphorus (P), 1.02% lysine, 1.02% methionine and cysteine mixture. After a 7-day adaptation period, the birds were randomly assigned to 3 groups, one control (n = 10) and two others as test groups (n = 11 and n = 12). Birds in test groups were subcutaneously injected with 0.1 or 0.2 mg E2. Blood samples were collected from the jugular vein and serum mineral concentrations were measured by HNO3 digestion method. Injection of 0.2 mg E2 resulted with a significant reduction in serum potassium concentration as compared to control group. Injection of 0.2 mg E2 caused a significant reduction in serum iron concentration as compared to 0.1 mg E2 injected group. Injection of 0.1 mg E2 caused a significant increase in serum chromium concentration over the control. Serum boron concentration was significantly high after the injection of 0.1 or 0.2 mg E2 over the control group. Effect of E2 on serum mineral concentration depends on injection dose. An injection of 0.1 or 0.2 mg E2 significantly increased serum boron concentration, which is an indication for the effect of E2 on bone mineralization and feed conversion ratio. Thus, administration of boron or E2 may protect postmenopausal women against osteoporosis and estradiol can be employed for the treatment of osteoporosis. Injection of 0.1 mg E2 caused a significant increase in serum chromium concentration, which indicates the function of E2 on body growth and reproductive performance. Injection of 0.2 mg E2 caused significant reduction in serum potassium (K) concentration, while there was a slight increase in serum sodium (Na) concentration. This indicates the involvement of E2 in rennin-angiotensin-aldosterone system.

Copper(II) complexes with novel chelator-type nucleosides: histidine modified 2′-deoxyriboadenosine (N-[(9-β-D-2′-deoxyribofuranosylpurin-6-yl)-carbamoyl]histidine) and histamine modified 2′-deoxyriboadenosine (N-[(9-beta-D-2′-deoxyribofuranosylpurin-6-yl)-carbamoyl]histamine) were studied by potentiometric and spectroscopic (UV–VIS, CD, EPR) techniques. A histidine or histamine residue was inserted in the purine part of a nucleoside. The ligands can act as bidentate or tridentate, depending on the pH range. The Cu(II) ions bind specifically to the modified deoxynucleosides forming very stable chelates. In acidic pH, a very stable dimeric complex Cu2L2 predominates, with coordination spheres of both metal ions composed of oxygen atoms from carboxylic groups, one oxygen atom from ureido group and two nitrogen atoms derived from a purine base and histidine ring. Above pH 5, deprotonation of carbamoyl nitrogens leads to the formation of CuL2, Cu2L2H-1 and Cu2L2H-2 species. The CuL2H-1 and CuL2H-2 complexes, with three or four nitrogens in Cu(II) coordination sphere, have been detected in alkaline medium. The cleavage of double stranded pEGFP-C1 in 5 mM Tris–HCl/5 mM NaCl buffer (pH, 7.5) by ligands and Cu(II) complexes, in the absence of any reducing agent has been studied by gel electrophoresis. The ligands and their copper complexes have introduced single-strand nicks into pEGFP-C1 plasmid DNA at micromolar concentrations, converting the supercoiled into open circular forms. The chelates have been found to be more active as DNA cleavers than the free ligands.

The present work investigates forced convective heat transfer characteristics of alumina-water nanofluids in a turbulent flow regime. Nanofluids are dilute colloidal suspensions with nano-sized particles ( < 100 nm) dispersed in a basefluid. The thermal conductivity values are measured by a steady state method, using a guarded hot plate (GHP) apparatus customized for liquids. The forced convective heat transfer characteristics are evaluated with the help of a test loop maintained in a constant heat flux condition. Controlled experiments under a turbulent flow regime are carried out using four particle concentrations (0.5vol%, 1vol%, 2vol% and 4vol %). The experimental results show that, the thermal conductivity of nanofluids increases with an increase in particle concentration and closely follow effective medium theories. However, the enhancement of heat transfer coefficients in the turbulent regime is observed to be within the measurement uncertainty.

Rod-shaped antimony sulphoiodide (SbSI) crystals were grown by utilizing elemental components of the compound. The material was characterized by X-ray diffraction (XRD), Raman and surface morphology by SEM. Electrical conductivity was measured on the pallets of powdered SbSI by the four-probe technique in the temperature range of 4–300K, and by the two-probe technique in the temperature range of 300–550K. SbSI shows semiconducting behavior in the temperature range of 300–550K and metallic below 300K. Activation energy of an electrical conduction between 300–550K, is 1.87 eV.

This paper presents a summary of the results of a one-year student-faculty research project on environmental sustainability in Qatar's prime knowledge economy vehicle, the Qatar Foundation (QF), and its home, Education City (EC), in Doha. The project's main objective was to produce new information on the emergence of environmental sustainability policy and practice on the QF's agenda from a number of angles. The research team adopted a multi-level, multi-method approach to the topic, analyzing developments on three hierarchically interlinked levels: (i) strategic priorities of the State of Qatar and QF; (ii) initiatives and projects in EC; and (iii) individual attitudes and self-reported behavior of EC undergraduate students. A variety of research methods were employed, including document-based analysis, semi-structured interviews and survey research. The survey, administered in November 2012-February 2013, yielded a sample of 114 responses. Highlights of the survey analysis are presented in this summary paper.

The study is believed to have been the first comprehensive look at the evolution of QF's ambitious agenda to investigate, implement and promote environmental sustainability in EC. In addition to understanding the rationale underpinning the QF's commitment, the study also explored how the QF's goals are implemented by QF divisions and university administrations. Also, how EC's different sustainability programs are understood and received by its core constituency, the students. QF's commitment to environmental sustainability is both a key contributor to Qatar's national development and a significant component of its global brand. Therefore, understanding the achievements and challenges in translating ideals of environmental sustainability into practice in EC not only provides a useful basis upon which programs and initiatives may be strengthened and expanded, but also offers important lessons for other institutions in the country and the region. The paper concludes with a number of recommendations, based on the results of the research, relating to improving the effectiveness of sustainability policy in Education City.

The project was funded through the Qatar National Research Fund's Undergraduate Research Experience Program.

The objective of this study was to investigate the effect of treatment of whole barley grain (WBG) with sodium hydroxide (NaOH) on in vitro rumen gas production parameters and microbial protein synthesis. Experimental treatments included untreated whole barley grain (BControl) and treated barley grain with NaOH+water (35 g+220 ml/kg DM WBG) for 30 days (BNaOH). In vitro gas production technique was used to determine the gas production parameters of the samples. Furthermore, gas volume, apparent substrate degradability of barley grain (ASD), true substrate degradability of barley grain (TSD) and microbial N at t1/2 for two treatments were measured. The amount of produced gas at each time of incubation in each glass serum bottle was taken as the gas production parameter. Results of the in vitro technique revealed that alkali treatment of WBG caused a significant increase in the asymptotic gas volume (b) versus BControl (113.71 and 162.86 ml, respectively). Constant rate of gas production (c) significantly decreased by BNaOH compared with BControl (0.018 and 0.034 ml/h, respectively). No effects of NaOH treatment were observed on ASD and TSD of whole barley grain. However, rumen microbial-N yield considerably (p < 0.05) built up (from 1.922 to 4.087 mg) from the treatment of barley with NaOH. The finding of the present study leads us to conclude that treatment of WBG with NaOH improved in vitro gas production parameters and microbial protein synthesis.

The objective of this study is to evaluate sand encroached degradation in arid-land, with a predominantly agricultural ecosystem, using geospatial technologies. The study primarily involves the assessment of land degradation severity, severity change dynamics and temporal land-use change patterns, such as growth or shrinkage. Land use/land cover (LULC) change dynamics were analyzed for eight featured classes, derived using a K-means supervised classification method. Overall accuracy and kappa statistics obtained were 91.68% and 0.904 for the year 2001, while 90.85% and 0.896 for year the 2006. The analysis revealed that change dynamic patterns were highest for sand-affected areas and built-up classes, showing positive trend and an overall change of 8.92% and 5.34%, respectively. Degradation severity change dynamics and change patterns clearly showed an increasing trend in highly severe degradation areas (dynamic change 5.55 km²/change pattern 0.093%), followed by severe degradation (dynamic change 31.22 km²/change pattern 0.52%). However, the maximum change was observed in moderately severe zones.

The sweetpotato weevil, Cylas puncticollis Boheman, constitutes a major constraint to sweet potato production and utilization in Africa. Host plant resistance/tolerance, mulching and varying harvesting dates could provide an approach that fits well into an integrated pest management programme of this insect pest. In this study, a trial was conducted to evaluate the effect of host plant, mulching with freshly harvested, dried and chopped up aerial parts of elephant grass (Panicum maximum), and the manipulation of harvesting date, on crop damage by the sweetpotato weevil. The experiment was laid out in a randomized complete split-split plot design with three replications. Four sweet potato varieties (improved variety- kabbia, slipot 2, slipot 3 and slipot 4), four harvesting dates (90, 104, 118 and 132 days after planting (DAP)) and four mulching levels (0t/ha, 1t/ha, 3t/ha and 5t/ha) were used. Data analysis revealed significant differences in C. puncticollis tuber damage and number of tubers produced with respect to mulching. Cylas puncticollis incidence was observed to decrease with increase in mulching level. Also, significant cultivar variation with respect to C. puncticollis tuber damage and the total number of tubers produced were recorded. Slipot 3 and slipot 4 were observed to be significantly less susceptible to the sweetpotato weevil. Harvesting date was also significantly different, with respect to the number of damaged tubers. More tubers were damaged when harvesting was delayed. Hence, using slipot 3 or slipot 4, coupled with mulching at the rate of 3-5t/ha and harvesting at 104 DAP resulted in increased number of tubers and reduced sweetpotato weevil infestation in the field.

A maximum of 8.75 wt% hydrogen adsorption was observed by carbon fibers which were obtained by the pyrolysis of cotton. Cotton was pyrolysed at 750°C for 3 h in argon atmosphere. Carbon fiber was soaked with 0.1M Ni(NO3)2. This was filtered and dried at 100°C. Finally, metal nitrate treated carbon fibers were heated at 850°C for 3 h in argon atmosphere. Carbon fibers thus obtained were found to absorb hydrogen to the extent of 8.75 wt%. Taguchi optimization technique was adopted to find out the best parameters responsible to give highest hydrogen adsorption. Carbon fibers that showed 8.75 wt% hydrogen adsorption were characterized by SEM, TEM, XRD, and Raman analysis.

A new chromium(III) salt (C3H5N2)[Cr(C2O4)2(H2O)2].2H2O, trans-diaquabis(oxalato) chromate(III) imidazolium dihydrate, has been synthesized and characterized by single crystal X-ray diffraction. This compound crystallizes in the monoclinic system, C2/c space group with a = 10.836(1)Å, b = 7.541(1)Å, c = 16.349(3)Å and β = 93.52(1)°. The structure of the title compound consists of [Cr(C2O4)2(H2O)2]⁻  mononuclear anions, imidazolium cations and uncoordinated water molecules. The crystal structure data indicates that the Cr ^+III ion is six coordinated in a distorted octahedral geometry, with four equatorial O atoms of two oxalate anions acting as chelating ligands and two axial O atoms from two water molecules. Structural cohesion is established by intermolecular O–H…O hydrogen bonds connecting the ionic entities and water molecules. In fact, both coordinated and uncoordinated water molecules play an important role in the hydrogen-bonded system, stabilizing the structure. Magnetic susceptibility measurements of the title compound in the range 2-300K exhibit paramagnetic behavior at high temperature. However, at low temperature, the magnetic data show the occurrence of weak antiferromagnetic intermolecular interactions between the local spin.