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Oxasetin from Lophiostoma sp. of the Baltic Sea: identification, in silico binding mode prediction and antibacterial evaluation against fish pathogenic bacteria

Because of the evolving resistance of microorganisms against existing antibiotics, there is an increasing need for new ones, not only in human, but also in veterinary medicine. The dichloromethane extract of a fungal strain of the genus Lophiostoma, isolated from driftwood collected from the coast of the Baltic Sea, displayed antibacterial activity against some fish pathogenic bacteria. Ergosterol epoxide (1), cerebroside C (2) and oxasetin (3) were isolated from the extract and structurally elucidated on the basis of spectroscopic data and chemical evidence. Compound 3 exhibited in vitro activity against Vibrio anguillarum, Flexibacter maritimus and Pseudomonas anguilliseptica with minimal inhibitory concentrations of 12.5, 12.5 and 6.25 microg/mL, respectively. Molecular docking studies were performed to understand the interaction of compound 3 with different macromolecular targets. Analysis of in silico results, together with experimental findings, validates the antimicrobial activity associated with compound 3. These results may be exploited in lead optimization and development of potent antibacterial agents. arabic 23 English 137
Muftah A Shushni, Faizul Azam, Ulrike Lindequist, (9-2013)

Balticolid: a new 12-membered macrolide with antiviral activity from an ascomycetous fungus of marine origin

A new 12-membered macrolide, balticolid (1) was isolated from the EtOAc extract of the culture broth of fungal strain 222 belonging to the Ascomycota, which was found on driftwood collected from the coast of the Greifswalder Bodden, Baltic Sea, Germany. The structure of balticolid was determined to be (3R,11R), (4E,8E)-3-hydroxy-11-methyloxacyclododeca-4,8-diene-1,7-dione using extensive spectral data as well as the modified Mosher ester method. Balticolid (1) displayed anti-HSV-1 activity with an IC₅₀ value of 0.45 μM.A new 12-membered macrolide, balticolid (1) was isolated from the EtOAc extract of the culture broth of fungal strain 222 belonging to the Ascomycota, which was found on driftwood collected from the coast of the Greifswalder Bodden, Baltic Sea, Germany. The structure of balticolid was determined to be (3R,11R), (4E,8E)-3-hydroxy-11-methyloxacyclododeca-4,8-diene-1,7-dione using extensive spectral data as well as the modified Mosher ester method. Balticolid (1) displayed anti-HSV-1 activity with an IC₅₀ value of 0.45 μM. arabic 16 English 92
Muftah A. Shushni, R Singh, R Mentel, U Lindequist(9-2011)
موقع المنشور

Balticols A-F, new naphthalenone derivatives with antiviral activity, from an ascomycetous fungus

Six new naphthalenone derivatives, balticols A-F and the known metabolite altechromone A were isolated from the AcOEt extract of the culture broth of fungal strain 222 belonging to the Ascomycota, which was found on driftwood collected at the coast of the Greifswalder Bodden, Baltic Sea, Germany. All structures were elucidated on the basis of NMR spectroscopic data and mass spectrometric analyses. The balticols were found to exhibit inhibitory activity against influenza virus A and herpes simplex virus. The most potent antiviral activity was observed for balticol E with an IC(50) value of 0.01 microg/ml against Herpes simplex virus type I. arabic 14 English 83
Muftah A. Shushni, Renate Mentel, Ulrike Lindequist, Rolf Jansen(2-2009)
موقع المنشور

Database for Arabic Speech Commands Recognition

Technology is all around us and it’s changing rapidly, expanding Internet access has had huge impacts on everyday lives as people do everything on their phones and computers. The widespread growth in the use of digital computers, have an increasing need to be able to communicate with machines in a simpler manner. One of the main tasks that can simplify communication with machines is speech recognition. In this work, we introduce the Arabic speech commands database that contains six Arabic control order words and Arabic spoken digits. The created database is used to analyze and compare the recognition accuracy and performance of three recognition techniques which are, Wavelet Time Scattering feature extraction with Support Vector Machine (SVM) classifier, Wavelet Time Scattering feature extraction with Long Short-Term Memory (LSTM) classifier, and Mel-Frequency Cepstrum Coefficients (MFCC) feature extraction with K-Nearest Neighbor (KNN) classifier. Finally, the experimental results show that the most accurate prediction of the database commands was 98.1250% given by Wavelet Time Scattering feature extraction and LSTM classifier and the fastest training time for the database was 144 minutes given by MFCC and KNN classifier. arabic 5 English 42
Osama A. Alkishriwo, Lina Tarek Benamer(12-2020)
عرض موقع المنشور

A Novel Denoising Method Based on Discrete Linear Chirp Transform

Denoising of chirp based signals is a challenging problem in signal processing and communications. In this paper, we propose a suitable denoising algorithm based on the discrete linear chirp transform (DLCT), which provides local signal decomposition in terms of linear chirps. Analytical expression for the optimal filter response is derived. The method relies on the ability of the DLCT for providing a sparse representation to a wide class of broadband signals like chirp signals. Simulation results show the efficiency of the proposed method, especially for mono-component chirp signals.
Osama A. Alkishriwo(12-2020)
عرض موقع المنشور

Image compression using adaptive multiresolution image decomposition algorithm

With the growth of modern digital technologies, demand for transmission multimedia and digital images, which require more storage space and transmission bandwidth, has been increased rapidly. Hence, developing new image compression techniques for reducing data size without degrading the quality of the image, has gained a lot of interest recently. In this study, an adaptive multiresolution image decomposition (AMID) algorithm is proposed and its application for image compression is explored. The developed algorithm is capable of decomposing an image along the vertical, horizontal, and diagonal directions using the pyramidal multiresolution scheme. Compared to the wavelet transform, the AMID can be used for decimation with the guarantees of perfect signal reconstruction. Furthermore, the application of the AMID for image compression is explored and its performance is compared with the state-of-the-art image compression techniques. The performance of compression method is evaluated using peak signal-to-noise ratio and compression ratio. Experimental results have shown promising performance compared with the results of using other image compression approaches
Osama A. Alkishriwo(9-2020)
موقع المنشور

Usability of soil survey soil texture data for soil health indicator scoring

Soil textural information is an important component underlying other soil health indicators. Soil texture analysis is a common procedure, but it can be labor intensive and expensive. Soil texture data typically are available from the Soil Survey Geographic (SSURGO) database, which may be an option for determining soil health texture groups (SHTG). The SSURGO database provides soil texture information in the soil map unit (SMU) name, taxonomic class category (family), and detailed values (≤ 2 mm soil fraction) of percent sand, silt and clay by soil horizon. The objective of this study was to examine the possibility of using SSURGO data for SHTG at the 147-ha Cornell University Willsboro Research Farm in New York state as an alternative for soil texture data determined manually on collected soil core samples. Comparative results revealed that representative values for soil texture from the SSURGO database generally matched measured mean values for all SMUs. arabic 11 English 65
Elena Mikhailova, Christopher Post, Mark Schlautman, John Galbraith, Hamdi Zurqani(9-2019)
موقع المنشور

Assessing the value of soil inorganic carbon for ecosystem services in the contiguous United States based on liming replacement costs

Soil databases are very important for assessing ecosystem services at different administrative levels (e.g., state, region etc.). Soil databases provide information about numerous soil properties, including soil inorganic carbon (SIC), which is a naturally occurring liming material that regulates soil pH and performs other key functions related to all four recognized ecosystem services (e.g., provisioning, regulating, cultural and supporting services). However, the ecosystem services value, or “true value,” of SIC is not recognized in the current land market. In this case, a negative externality arises because SIC with a positive value has zero market price, resulting in the market failure and the inefficient use of land. One potential method to assess the value of SIC is by determining its replacement cost based on the price of commercial limestone that would be required to amend soil. The objective of this study is to assess SIC replacement cost value in the contiguous United States (U.S.) by depth (0–20, 20–100, 100–200 cm) and considering different spatial aggregation levels (i.e., state, region, land resource region (LRR) using the State Soil Geographic (STATSGO) soil database. A replacement cost value of SIC was determined based on an average price of limestone in 2014 ($10.42 per U.S. ton). Within the contiguous U.S., the total replacement cost value of SIC in the upper two meters of soil is between $2.16T (i.e., 2.16 trillion U.S. dollars, where T = trillion = 1012) and $8.97T. States with the highest midpoint total value of SIC were: (1) Texas ($1.84T), (2) New Mexico ($355B, that is, 355 billion U.S. dollars, where B = billion = 109) and (3) Montana ($325B). When normalized by area, the states with the highest midpoint SIC values were: (1) Texas ($2.78 m−2), (2) Utah ($1.72 m−2) and (3) Minnesota ($1.35 m−2). The highest ranked regions for total SIC value were: (1) South Central ($1.95T), (2) West ($1.23T) and (3) Northern Plains ($1.01T), while the highest ranked regions based on area-normalized SIC value were: (1) South Central ($1.80 m−2), (2) Midwest ($0.82 m−2) and (3) West ($0.63 m−2). For land resource regions (LRR), the rankings were: (1) Western Range and Irrigated Region ($1.10T), (2) Central Great Plains Winter Wheat and Range Region ($926B) and (3) Central Feed Grains and Livestock Region ($635B) based on total SIC value, while the LRR rankings based on area-normalized SIC value were: (1) Southwest Plateaus and Plains Range and Cotton Region ($3.33 m−2), (2) Southwestern Prairies Cotton and Forage Region ($2.83 m−2) and (3) Central Great Plains Winter Wheat and Range Region ($1.59 m−2). Most of the SIC is located within the 100–200 cm depth interval with a midpoint replacement cost value of $2.49T and an area-normalized value of $0.34 m−2. Results from this study provide a link between science-based estimates (e.g., soil order) of SIC replacement costs within the administrative boundaries (e.g., state, region etc.). arabic 19 English 114
Garth Groshans, Elena Mikhailova, Christopher Post, Mark Schlautman, Hamdi Zurqani, Lisha Zhang(12-2018)
موقع المنشور