Genetically encoded calcium indicators (GECIs) have gained widespread use for measurement of neuronal activity but their low expression levels in transgenic mice tend to limit sensitivity. We have developed a transgenic mouse line (SyG37) that expresses a ratiometric calcium sensor, SyGCaMP2-mCherry, that is expressed throughout the brain but targeted to presynaptic terminals. Within the CA1 and CA3 regions of hippocampus of male and female mice, SyGaMP2 fluorescence responds linearly up to 10 electrical stimuli at frequencies up to 100 Hz and it can detect responses to a single stimulus. Responses in single boutons can be measured using multiphoton microscopy. The ensemble amplitude of SyGCaMP2 responses is a function of the number of stimuli applied and the number of contributing boutons. The peak responses and initial rates of calcium influx in single boutons in CA1 and CA3 were similar but the rate of calcium clearance from CA3 boutons after stimulation was significantly faster. In CA1, DNQX reduced SyGCaMP2 responses to Schaffer collateral stimulation to 86% of baseline indicating that 14% of the total response originated from presynaptic terminals of neurones synaptically driven via AMPA receptors. Theta burst stimulation induced long-term potentiation (LTP) of both SyGCaMP2 and fEPSP responses in both young and 18-month-old mice. The proportion of postsynaptically connected terminals increased significantly to 76% of the total after LTP induction. The SyG37 mouse allows stable optical detection of synaptic activation and connectivity at the single bouton level and can be used to characterize the contributions of presynaptic calcium to synaptic transmission and plasticity.

Alzheimer’s disease (AD) is a progressive age-related neurodegenerative disorder characterized by progressive impairment of memory and cognitive functions. Oxidative stress, neuroinflammation, and neurotransmitters disturbance may play an important role. This study aimed to evaluate the effect of donepezil alone and in combination with nitric oxide synthase (NOS) substrate L-arginine, and nitric oxide synthase inhibitor (NOSi) Ng-nitro-l-arginine methyl ester hydrochloride (L-NAME) and 7-nitroindazole against aluminum chloride (AlCl3) induced neurotoxicity. A total of 36 male albino rats were divided to six groups: control normal saline, AlCl3. ,Donepezil, Donepezil+ L-arginine, Donepezil+ L-NAME, and Donepezil+7-nitroindazole. Neurotoxicity was induced by AlCl3 in a dose of 10 mg/Kg subcutaneously for 30 days. After the experimental period, brain was removed for determination of acetylcholinesterase activity (AChE), levels of fatty acids fractions by high performance liquid chromatography (HPLC), interleukin 1β (IL-1β) and tumor necrosis factor alpha (TNF-α). AlCl3 significantly increase brain levels of AChE, IL-1β, and TNF-α, and arachidonic acid (AA) and linoleic acid (LA). Treatment with Donepezil alone and in combination with L.NAME and 7-nitroindazole significantly attenuates these changes. In conclusion, regulation of nitric oxide (NO) level is the key for stability and prevention of neurodegenerative diseases. Combination of Donepezil with nitric oxide synthase inhibitors especially 7-nitroindazole attenuates the oxidant and inflammatory induced by AlCl3.

Keywords: AlCl3, L. NAME, Donpezil, fatty acids, HPLC

This research paper was motivated by the observation that exams are the main (if not the sole) method of assessment in the postgraduate programs in the English departments in the University of Zawia and the Libyan Academy. The aim was investigating and experimenting the use of assignment as another method of assessing students’ achievement.

To fulfill this aim, the researcher taught the students in the two English departments separately and simultaneously one of the subjects, namely ELT Methodology. Instead of giving them a typical midterm exam, students were asked to do an assignment in which they evaluate the suitability of some textbooks in teaching and learning English as a foreign language and adapt these books to be suitable for the Libyan context. The same students were given a formal and final exam at the end of the course. The comparison of the scores of the two assessment methods has shown that students did better in the assignment than in the exam. This has supported the results of the questionnaire which was given to the same students. These results indicated that half of the students preferred using assignments to using exams while another considerable number preferred the use of a mixture of assignments and exams. Only a few students selected exams as their preferred method of assessment.

Therefore, it is recommended that assignment as a method of assessing students achievement should be integrated into MA programs in Libyan universities and academies due to its role in improving the students’ practical skills and abilities and enhancing their understanding of the learned subjects.  

Cutting samples (n = 150) and Core samples (n = 6) from the Taouratine, Dembaba, Assedjefar Marar, Awaynat Wanin, Tanezzuft and Mamuniyat Formations ( Jurassic to Ordovician), derived from wells (A-3, B-1, H-1 and H-15), locate in the A, B and H fields, present in Murzuq Basin were analysed. Rock-Eval Pyrolysis, Total Organic Carbon and specific Aromatic Molecular Biomarker (by the use of chromatography- mass spectrometry GC-MS) as geochemical parameters implemented to investigate their Lithology, kerogen type, organic matter (OM) richness and maturity evaluation. Such Formations are fair to very good quantity of organic matter passing in the course of excellent source rocks, have average of organic carbon richness (TOC) value ranged between 0.2% to 16.7% with one anomalously rich sample at 666m (well H-1) where a dark grey shale has a TOC content of 46.1% and high potential yield over 90000 ppm. The studied rocks are ranged from immature to mature of hydrogen index (HI) ranged between 24 - 302 mg HC/g TOC versus pyrolysis Tmax, with dominance of kerogen II/III Type, resulted based on HI versus oxygen index (OI), ranged from 3 to 161 mg CO2/g TOC. The Tmax , spore colouration (SCI) and Vitrinite Reflectance (% Ro) as maturity parameters ranged among 425 - 445, 5 - 8.5 and 0.35 - 3 respectively.

Aromatic hydrocarbon ratios by use of gas chromatography - mass spectrometry pointed to two levels of thermal maturity, where the high level of thermal maturity recorded in lower Silurian, whereas the less maturity was from other formations

This paper presents some initial studies for characterizing effects of human body movements on short range indoor links at 18-22 GHz. Firstly, measurement system is described, and then, calibration measurements along with initial results of the impact of human body movement on the channel are presented for some scenarios.