The 21st century Northern Nigerian woman and challenges of womanhood: A reading of Zaynab Akali's The Initiates

No Abstrac

STRUKTUR, BIOAKTIVITAS DAN ANTIOKSIDAN FLAVONOID

Di antara produk-produk alami, flavonoid  adalah yang sangat menarik untuk dipelajari dan merupakan salah satu senyawa yang menjanjikan  untuk mengobati kanker, antioksidan, bakteri patogen, radang, disfungsi kardio-vaskular, dan lain-lain. Kemampuan dan bioaaktiftas terutama antioksidan dari  flavonoid telah dipelajari, dalam hal ini ditunjukkan bahwa metilasi flavonoid dapat meningkatkan peranan flavonoid dalam bidang obat-obatan. Metilasi dari flavonoid melalui kelompok hidroksil bebasnya atau atom C yang dapat meningkatkan stabilitas metaboliknya dan meningkatkan transportasi membran. Review ini menjelaskan struktur dasar dan klasifikasi flavonoid, dan isolasi dan bioaktiftas dari flavonoid yang khususnya dalam peranannya sebagai antioksidan. Mekanisme flavonoid sebagai antioksidan secara kimia dan tahapannya juga dipelajari

Pandangan Maqashid Al-Syariah Terhadap Ekploitasi Lobster di Kabupaten Simeulue

Penelitian ini menjelaskan ekploitasi lobster di Kabupaten Simeulue dalam perspektif maqashid al-syariah. Lobster merupakan sumber daya alam hewani yang bermanfaat bagi manusia baik sebagai sumber protein maupun sebagai sumber pendapatan (ekonomi). Lobster merupakan salah satu komoditas yang banyak diminati, di kancah bisnis lobster, menyasar pangsa pasar lokal dan dunia. Lobster dianggap punah jika ada penangkapan ikan terus menerus yang tidak mempertimbangkan perlindungan biota laut tersebut. Maka penelitian ini diusulkan untuk mengetahui praktik eksploitasi lobster di Kabupaten Simeulue dengan pendekatan maqashid al-syariah. Menempatkan maqashid al-syariah sebagai pisau analisis dinilai mampu mengungkap tujuan hukum Islam universal, termasuk perlindungan alam (hifz al-bi'ah) dalam hal ini perlindungan lobster. Penelitian ini menggunakan metode penelitian kualitatif, pengumpulan data dilakukan dengan wawancara, observasi, dokumentasi, dan analisis data dilakukan dengan teknik deskriptif. Berdasarkan hasil penelitian dapat disimpulkan. Pertama, praktik pemanfaatan lobster di Kabupaten Simeulue dimulai dengan penangkapan lobster di laut lepas oleh nelayan kemudian memperdagangkannya kepada konsumen atau agen pengumpul dengan harga jual rata-rata Rp. 370.000,00.-/Kg. Kedua, Penangkapan Lobster yang dilakukan oleh nelayan dinilai tidak memperhatikan kelestarian Lobster karena nelayan juga menangkap Lobster di bawah standar (kurang dari 1 ons) dan masih tergolong baby Lobster. selain itu nelayan juga menangkap Lobster yang mengandung telur sehingga keberadaan Lobster di Kabupaten Simeulue semakin langka. Ketiga, dalam perspektif maqashid al-syariah Islam memiliki orientasi untuk menjaga kelestarian alam dari kerusakan (dar'ul mafasid wa jalbul mashalih) termasuk melestarikan lobster (hifz al bi'ah)

ISOLASI KUMARIN DARI BIJI PINANG (Areca catechu L.)

 ABSTRACT Coumarin has been isolated from seed of Areca catechu L. an ethyl acetate fraction which needle crystal products at 184 –185°C. Based on thin layer chromatography analysis using n-hexane  : acetone (4 : 6) as eluent got Rf 0.6. From elemental analysis, mass spectra, ultraviolet spectra, infra red spectra, nuclear magnetic resonance spectra ( H and C NMR) ,concluded this compound was 7-hidroksi-4-metil coumarine.                                                       Keywords : Areca catechu, 7-hidroksi-4-metil kumarin

Screening for active agent to anti-diarrhea by an evaluation of antimicrobial activities from three fractions of sappan wood (Caesalpinia sappan. L)

The object of this research was to evaluate and compare the antimicrobial activities of three fractions sappan wood (Caesalpinia sappan. L.) also known as sappan wood, that was methanol, ethyl acetate, and hexane fractions. The sappan wood was collected from traditional market, minced, extracted by methanol and fractionationtreatment by nhexane continues by ethyl acetate. These fractions were evaluated for antimicrobial activity against bacteria Escherichia coli and Staphylococcus aureus using the cup-plate agar diffusion method in Nutrient Agar medium to determine the minimum inhibitory concentration (MIC). The phytochemical of it extract was also analysis by test identification tests. The phytochemical of sappan wood proved the presence of phenolic, flavonoid, tannins and a little bit of terpenoid and saponin but no alkaloid and steroid compound. Out of the three fractions of sappan wood, the methanol fraction showed maximum average clear zone inhibition against. Antimicrobial activity from the three fraction(n-hexane, ethyl acetate, and methanol) of it wood showed that methanol fraction has the best value. The inhibition maximum concentration value of methanol extract of it to E.coli and S.aureus were 13,7± 0,6 mm and 16,3±2,1 mm, it recommended for use as agent antimicrobial to disease diarrhea earlier

Sawdust types effective as partial replacements of fine aggregate in concrete

The paper examined the types of sawdust suitable as partial replacements of fine aggregate in concrete. Two different types of sawdust sourced from Afara and Doka wood species were used for the experiment. DoE Method was used to design and produce three sets of concrete cube samples, i.e. Control concrete, Doka sawdust concrete and Afara sawdust concrete, each of grade 20. The cubes were subjected to compressive strength and water absorption tests. The result showed that, the control concrete, Doka and Afara sawdust concretes gained a compressive strength of 22.6 N/mm2, 19.6 N/mm2 and 17.6 N/mm2, respectively. The control and Doka sawdust concretes exhibited low water absorption when compared with Afara sawdust concrete. This revealed Doka sawdust as more suitable than Afara sawdust for partial replacement of fine aggregate in concrete.Keywords: Concrete, Sawdust, waste recyclin

ANTIOXIDANT ACTIVITY OF METHYL GALLATE ISOLATED FROM THE LEAVES OF Toona surenl

ABSTRACT An antioxidant compound has been isolated from the leaves of Toonasureni (Blume) Me". The structure was determined to be methyI3,4,5-trihydroxybenzoate (methyl gallate), based on UV-vis, FTlR, NMR and MS spectra. The isolated compound exhibited potent antioxidant activity in the a,a-diphenyl-/3-picrylhydrazyl(DPPH) radical scavenging test, with ICsovalue 1.02fJg/mL. Keywords: antioxidant activity, methyl gallate, Toonasure

OPTIMAL AND ADAPTIVE CONTROL FRAMEWORKS USING REINFORCEMENT LEARNING FOR TIME-VARYING DYNAMICAL SYSTEMS

Performance of complex propulsion and power systems are affected by a vast number of varying factors such as gradual system degradation, engine build differences and changing operating conditions. Owing to these variations, prior characterisation of the system performance metrics such as fuel efficiency function and constraints is infeasible. Existing model-based control approaches are therefore inherently conservative at the expense of the system performance as they are unable to fully characterise the system variations. The system performance characteristics affected by these variations are typically used for health monitoring and maintenance management, but the opportunities to complement the control design have received little attention. It is therefore increasingly important to use the information about the system performance characteristics in the control system design whilst considering the reliability of its implementation. This thesis therefore considers the design of direct adaptive frameworks that exploit emerging diagnostic technologies and enable the direct use of complex performance metrics to deliver self-optimising control systems in the face of disturbances and system variations. These frameworks are termed condition-based control techniques and this thesis extends reinforcement learning (RL) theory which has achieved significant successes in the area of computing and artificial intelligence to the new frameworks and applications. Consequently, an online RL framework was developed for the class of complex propulsion and power systems that make use of the performance metrics to directly learn and adapt the system control. The RL adaptations were further integrated into existing baseline controller structures whilst maintaining the safety and reliability of the underlying system. Furthermore, two online optimal RL tracking control frameworks were developed for time-varying dynamical systems that use a new augmented formulation with integral control. The proposed online RL frameworks advance the state-of-the-art for use in tracking control applications by not making restrictive assumptions on reference model dynamics or use of discounted tracking costs, and guaranteeing zero steady-state tracking error. Finally, an online power management optimisation scheme for hybrid systems that uses a condition-based RL adaptation was developed. The proposed power management optimisation scheme is able to learn and compensate for the gradual system variations and learn online the optimal power management strategy between the hybrid power source given future load predictions. This way, improved system performance is delivered and providing a through-life adaptation strategy

Management of Abnormal Vaginal Discharge in Pregnancy

Abnormal vaginal discharge in a pregnant woman causes discomfort and increases risk of complications. Management of such patient is difficult as the physician will need to distinguish leucorrhoea of pregnancy from pathological vaginal discharge and also to decide on the drugs to prescribe that are not contraindicated in pregnancy