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1

Yield performance and Adaptability of Finger millet landrace in North Western Tigray, Ethiopia

100%

Kinfe H., Yiergalem T., Alem R., Redae W., Desalegn Y., Welegerima G.

World News of Natural Sciences

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2017

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vol. 15

98-111

EN

Finger millet (Eleusine coracana L. Gaertn.) is a stable food crop with inherent hardy nature and quality nutritional grain in majority of drought prone areas in several East African and South Asian countries in the world. The experiment was conducted with objectives of determining the effect of genotype, environment and their interaction for grain yield and to identify the most stable finger millet genotypes in north western Tigray, Ethiopia. Forty one finger millet genotypes were grown at three sites in northwestern Tigray, Ethiopia at two season (2015/16 and 2016/2017). The experiment was laid down in RCBD with three replications. The combined ANOVA for grain yield revealed highly significant (P<0.01) for genotypes, environments and their interactions. This indicated that the environments were diverse and variability among the genotypes. The significant interaction showed the genotypes respond differently across the different environments. The mean grain yield value of genotypes averaged over environments indicated that MyARC coll 44 and Tessema had the highest (2599 kg/ha) and lowest (1154 kg/ha) grain yield respectively. The best genotype with respect to site of Tselemti on station was genotype MyARC coll 44; for Tselemti Maiani also MyARC coll 61 and MyARC coll 61. Generally, the result revealed the existence of variability for the characters studied in finger millet landraces. Hence, this is a potential character of interest which could be used in the genetic improvement of finger millet through hybridization and/or selection by involving breeders and farmers’ knowledge. Farmers also opined that the new variety has better grain and fodder yield potential and lodging resistance and they would adopt them in future.

2

Chromatographic techniques in analysis of cyclooxygenase-2 inhibitors in drugs and biological samples

88%

Starek M., Dąbrowska M.

Open Chemistry

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2012

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vol. 10

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issue 3

711-730

EN

Non-steroidal anti-inflammatory drugs, as a therapeutic class, are among the most often used active pharmaceutical ingredients in heath care in the world. They are mostly available without prescription and often used for treatment of fever and pain. An extensive research of the literature published in analytical and pharmaceutical chemistry journals has been conducted and the chromatographic methods which were used for the purity, stability and pharmacokinetic studies of the cyclooxygenase-2 inhibitors, in formulations and biological materials have been reviewed. The methodology for the analysis of selected drugs is very well documented and many examples are available in the literature. The common use of chromatographic techniques with various detection attachments provide possibility for monitoring of drugs in therapy.

3

Experimental and theoretical studies on the photodegradation of 2-ethylhexyl 4-methoxycinnamate in the presence of reactive oxygen and chlorine species

88%

Gackowska A., Przybyłek M., Studziński W., Gaca J.

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issue 5

612-623

EN

2-Ethylhexyl 4-methoxycinnamate (EHMC) is one of the most commonly used sunscreen ingredient. In this study we investigated photodegradation of EHMC in the presence of such common oxidizing and chlorinating systems as H2O2, H2O2/HCl, H2O2/UV, and H2O2/HCl/UV. Reaction products were detected by gas chromatography with a mass spectrometric detector (GC-MS). As a result of experimental studies chloro-substituted 4-methoxycinnamic acid (4-MCA), 4-methoxybenzaldehyde (4-MBA) and 4-methoxyphenol (4-MP) were identified. Experimental studies were enriched with DFT and MP2 calculations. We found that reactions of 4-MCA, 4-MBA and 4-MP with Cl2 and HOCl were in all cases thermodynamically favorable. However, reactivity indices provide a better explanation of the formation of particular chloroorganic compounds. Generally, those isomeric forms of mono- and dichlorinated compounds which exhibits the highest hardness were identified. Nucleophilicity of the chloroorganic compounds precursors were examined by means of the Fukui function.

4

Theoretical studies on the electronic structures and spectra of single silicon-doped SWCNTs

88%

Gao P., Yu Y., Ni Z., Teng Q.

Open Chemistry

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2010

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vol. 8

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issue 3

587-593

EN

The equilibrium geometries and electronic structures of a series of SWCNTs doped with a silicon atom were studied by using density function theory (DFT). The most stable doping site of silicon predicted at B3LYP/6-31G(d,p) level was located near the boundary of the SWCNTs. The energy gaps of (3,3) C48, (3,3) C60 and (3,3) C72 were respectively decreased by 0.43, 0.25 and 0.14 eV after doping. Based on the B3LYP/6-31G(d) optimized geometries, the electronic spectra of the doped SWCNTs were computed using the INDO/CIS method. The first UV absorption at 973.9 nm of (5,5)-Si(L) (C59Si) compared with that at 937.5 nm of (5,5) (C60) was red-shifted. The 13C NMR spectra and nuclear independent chemical shifts (NICS) of the doped SWCNTs were investigated at B3LYP/6-31G(d) level. The chemical shift at 119.4 of the carbon atom bonded with the silicon atom in (3,3)-Si(L) (C59Si) in comparison with that at 144.1 of the same carbon atom in (3,3) (C60) moved upfield. The tendency of the aromaticity (NICS = −0.1) for (3,3)-Si(H) (C47Si) with respect to that of the anti-aromaticity (NICS = 6.0) for (3,3) (C48) was predicted. [...]

5

Conductometric studies on the stability of copper complexes with different oligosaccharides

88%

Savic I., Nikolic G., Savic I., Cakic M.

Open Chemistry

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2010

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vol. 8

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issue 5

1078-1085

EN

Bioactive copper complexes with pullulan or dextran oligosaccharides are the subject of intensive research mainly because of their possible application in veterinary and human medicine. The thermal stability and stability under oxidative conditions of the Cu(II) complexes with reduced low-molar pullulan or dextran were investigated in this paper, using a conductometric method. The influence of ligand constitutions on the stability of the complexes was examined on the basis of ligand property. Forced degradation studies were performed on bulk sample of complexes by using heat (25, 40 and 60°C) and an oxidation agent (0.1, 0.5, 1.0 and 10.0% v/v hydrogen peroxide). It can be concluded, according to the results obtained (by examining conductivity during the forced degradation studies), that Cu(II) complexes show a large pharmaceutical stability for both tests. [...]

6

C12: The building block of hexagonal diamond

88%

Banfalvi G.

Open Chemistry

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2012

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vol. 10

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issue 5

1676-1680

EN

The crystalline structure of diamond may consist of C8, C10 or C12 building units. C8 was regarded as the building block of the hexagonal diamond also known as Lonsdaleite. Adamantane (C10H16) alicyclic hydrocarbon has the same arrangement of carbon atoms as the basic C10 unit of the cubic diamond lattice. C12 has five rings of mixed type, three of them in boat, two in chair conformation. Model building revealed that the C8 unit containing exclusively three rings in boat conformation does not exist. Further addition of carbon atoms to C8: a) results in C12 unit, b) allows the multiplication of C12 units, and c) by reducing the boat-to-chair ratio explains the hardness of the hexagonal diamond Lonsdaleite. The Lonsdaleite nucleus can be grown to special diamond grains with the outer atoms of the C12 building units replaced by different elements. This recognition can be utilized in the production of synthetic diamonds under high-pressure high-temperature conditions or in the chemical vapor deposition growth technique. [...]

7

Inter-molecular physiochemical characterization for etodolac-hydroxypropyl-β-cyclodextrin polymeric systems in solid and liquid state

88%

Sinha V., Amita, Chadha R., Goel H.

Open Chemistry

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2010

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vol. 8

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issue 4

953-962

EN

The purpose of this study was to explore the utility of hydroxypropyl-β-cyclodextrin (HP-β-CD) systems in forming inclusion complexes with the anti-rheumatic or anti-arthritic drug, etodolac (EDC), in order to overcome the limitation of its poor aqueous solubility. This inclusion system achieved high solubility for the hydrophobic molecule. The physical and chemical properties of each inclusion compound were investigated. Complexes of EDC with HP-β-CD were obtained using the kneading and co-evaporation techniques. Solid state characterization of the products was carried out using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), powder X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Studies in the solution state were performed using UV-Vis spectrophotometry and 1H-NMR spectroscopy. Phase solubility profiles with HP-β-CD employed was found to be AL type. Stability constants (Kc) from the phase solubility diagrams were calculated indicating the formation of 1:1 inclusion complex. Stability studies in the solid state and in liquid state were performed; the possible degradation by RP-HPLC was monitored. The dissolution studies revealed that EDC dissolution rate was improved by the formation of inclusion complexes. [...]

8

Body posture and selected stabilometric parameters among patients with depression

75%

Szczygieł E., Łopatka K., Madej M., Malec A., Golec J., Czechowska D., Masłoń A.

Medical Rehabilitation

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2015

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vol. 19(4)

13-18

PL

Wstęp: Pionowa postawa ciała wyróżnia człowieka spośród innych istot żywych. Wyznacza również specyficzne warunki dla ruchu. Elementem łączącym zarówno postawę, jak i ruch jest stabilność. Polega ona na statycznym i dynamicznym równoważeniu destabilizujących sił grawitacji oraz bezwładności przez pobudzenie odpowiednich grup mięśniowych. Zakłócenia kontroli posturalnej mogą być uwarunkowane różnymi czynnikami. Wśród nich wymieniany jest udział czynnika psychicznego. Celem przeprowadzonych badań była analiza wybranych zmiennych charakteryzujących stabilność posturalną osób z depresją. Materiał i metody: W badaniach wzięło udział 54 osoby, które przydzielono do dwóch grup. Do pierwszej grupy zakwalifikowano 28 pacjentów ze zdiagnozowaną depresją. Średnia wieku badanych wynosiła 37,25 +/- 3,88 lat. Do drugiej grupy zakwalifikowano 26 osób. Osoby te były w pełni zdrowe, rekrutowane z ogólnej populacji, u których wykluczono depresję i obniżenie nastroju. Średnia wieku badanych wynosiła 33,31 +/- 5,19 lat. Do badań oceniających stabilność wykorzystano platformę PEL 38 i oprogramowanie komputerowe TWIN 99. Wyniki: Uzyskane wyniki różniły się istotnie między grupami w zakresie pięciu zmiennych: zmian oscylacji środka ciężkości w płaszczyźnie czołowej i strzałkowej, średniego odchylenia w płaszczyźnie czołowej oraz w parametrach niestabilności: pola powierzchni i stosunku długości do powierzchni. Grupa z depresją w porównaniu z grupą kontrolną uzyskała wyższe wartości 4 z 5 ocenianych parametrów. Wnioski: Osoby z depresją cechuje zmniejszenie stabilności ciała w porównaniu do osób bez depresji.

EN

Introduction: A vertical posture distinguishes humans from other living beings. It also determines the specific conditions for movement. The element which connects body posture and movement is stability. It is based on the static and dynamic balancing of the destabilising forces of gravity and inertia through stimulating the appropriate muscle groups. A disruption of postural control may be conditioned by various factors, among which the literature mentions mental health. The purpose of this study was a comparative analysis of selected variables characterising the postural stability of persons with depression.Material and methods: The study involved fifty-four persons who were divided into two groups. The first group comprised 28 patients diagnosed with depression. The mean age of the participants was 37.25 +/ – 3.88. The second group consisted of 26 completely healthy persons who were recruited from the general population, excluding persons with depression or a low mood. The mean age of the participants was 33.31 +/ – 5.19 years. The postural stability was assessed using a PEL 38 posturographic platform and TWIN 99 computer software.Results: The results differed significantly between the two groups with regard to five variables: oscillations of the centre of gravity in the frontal and the sagittal planes, average deviation in the frontal plane, and deviations in the parameters of instability (the surface area and the ratio of length to the surface area). It was observed that the group with a diagnosis of depression displayed higher values in 4 out of 5 the evaluated parameters when compared to the control group.Conclusions: Persons with depression are characterised by a reduced body stability compared to those who do not suffer from depression.

9

Mathematical Modeling of Control Strategies for Visceral leishmaniasis

63%

Onyekwelu O. M., Baker N.

World News of Natural Sciences

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2021

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vol. 37

102-116

EN

In this paper, a deterministic mathematical model for the transmission dynamics of Visceral leishmaniasis (VL) was formulated and analyzed. The basic reproductive number R0 was obtained using the next generation matrix method. The model which was parameterized using the 2011 cases of Visceral Leishmaniasis in South Sudan, was used to assess two control measures. Numerical simulation reveals that the exposed population is reduced by high detection rate, and low biting rate of sandflies. Further, our model simulation gave the values of the contact rate of susceptible human, α1 and the detection rate of new cases, σ at which the basic reproductive number is less than one, (R0 < 1), equal to one (R0 = 1) and greater than one (R0 > 1).

Refine search results

Yield performance and Adaptability of Finger millet landrace in North Western Tigray, Ethiopia

Chromatographic techniques in analysis of cyclooxygenase-2 inhibitors in drugs and biological samples

Experimental and theoretical studies on the photodegradation of 2-ethylhexyl 4-methoxycinnamate in the presence of reactive oxygen and chlorine species

Theoretical studies on the electronic structures and spectra of single silicon-doped SWCNTs

Conductometric studies on the stability of copper complexes with different oligosaccharides

C12: The building block of hexagonal diamond

Inter-molecular physiochemical characterization for etodolac-hydroxypropyl-β-cyclodextrin polymeric systems in solid and liquid state

Body posture and selected stabilometric parameters among patients with depression

Mathematical Modeling of Control Strategies for Visceral leishmaniasis