70 research outputs found
Determination of significant parameters that drive fracture optimization in the Glauconite Formation, Southern Chile
The Glauconite Formation in the Magallanes Basin of Southern Chile is a clay- and silica-rich formation with low permeability. As with many of the unconventional resources, the Glauconite Formation requires a hydraulic fracturing operation to enhance the productivity of the wells in this area.
Data and pertinent information of fracturing, completion, and reservoir quality parameters along with post-fracture production data were collected to initiate a database of nearly 70 wells, to be used to develop a better understanding of the fracturing behavior, optimize the well stimulation, and overcome the major barriers in the hydraulic fracturing of the Glauconite Formation. The database of Glauconite wells was used in this study to identify the key parameters of the fracturing design, completion, and reservoir quality that have the greatest influence on well performance in this unconventional reservoir.
This study also attempts to identify the best treatment fluid to maximize well performance and the effects of different values of the major fracture treatments and completion parameters. Statistical and sensitivity analyses were applied to identify the most effective parameters on the initial production, early recovery, and Estimated Ultimate Recovery.
Results of this work show that water fracs are superior to hybrid fracturing fluids. Total fluid and proppant volumes strongly affect well performance. Other completion and reservoir parameters were found to have a lesser impact on well performance in the Glauconite wells of Southern Chile --Abstract, page iii
Karakterizacija terenskih izolata virusa zarazne bolesti Fabricijeve burze u Jordanu uporabom molekularnih metoda - kratko priopćenje.
The reverse transcriptase-polymerase chain reaction/restriction fragment length polymorphism (RTPCR/ RFLP) and RT-PCR specific primer to detect very virulent (vv) strains of infectious bursal disease virus (IBDV) were used for identification and characterization of Jordanian field isolates of IBDV that caused severe outbreaks. In this study, 80 bursa of fabricius samples were used from 20 commercial broiler chicken flocks in Jordan with clinical symptoms of IBDV. The RT-PCR/RFLP was conducted on a 743-bp fragment of the VP2 gene with the restriction enzymes BstNI and MboI. The results indicate the existence of IBDV field strains in Jordan. In addition, 60% of IBDV Jordanian isolates had unique RFLP patterns different from those previously published elsewhere. However, 20% of local IBDV strains were positive on using a specific primer for vvIBDV and had a unique RFLP pattern that differed from the Jordanian IBDV isolate and those previously published elsewhere.Lančana reakcija polimerazom uz prethodnu reverznu transkripciju/polimorfizam dužine restrikcijskih fragmenata (RT PCR/RFLP) i RT-PCR specifične početnice za jako virulentne sojeve virusa zarazne bolesti Fabricijeve burze (ZBFB) bile su rabljene za identifikaciju i karakterizaciju jordanskih terenskih izolata toga virusa koji su uzrokovali teški oblik bolesti. Za istraživanje je bilo rabljeno 80 uzoraka tkiva Fabricijeve burze uzetih iz 20 komercijalnih jata tovnih pilića u Jordanu u kojih su ustanovljeni klinički znakovi ZBFB a. RT-PCR/ RFLP proveden je na odsječku gena VP2 od 743-bp s restrikcijskim enzimima BstNI i MboI. Rezultati upućuju na postojanje terenskih sojeva virusa ZBFB-a od kojih je 60% izolata imalo jedinstveni RFLP obrazac različit od onoga već objavljenog drugdje. Ipak, 20% lokalnih sojeva virusa bilo je pozitivno uporabom specifične početnice za jako virulentni virus i imalo je jedinstveni obrazac RFLP različit u jordanskih izolata u odnosu na izolate objavljene drugdje
Effect of Frying Temperature and duration on the Formation of Trans Fatty Acids in Selected Fats and Oils
Trans fatty acids occur in food either naturally or produced during heat processing of food containing unsaturated fats. Naturally occurring trans fatty acids have different physiological and biological functions as compared to those formed in heat processed food which increase the risk of coronary heart disease. The aim of this study was to investigate the effect of heat treatments [heating temperature: 120, 150, 190 and 250°C and heating period: 10, 30, 60 and 180 minutes] on the amount of trans fatty acids (as elaidic acid) of fat and oil samples [two solid-state (margarine and ghee) and two liquids-state (olive oil and corn oil)]. Results showed that elaidic acid content in margarine was not affected by heat at 120°C at all studied heating durations. At 150, 190 and 250°C, there is a cubic significant relationship between elaidic acid content and time of heating. Elaidic acid content in ghee was not affected by heat treatment at 120°C, while at 150°C, there was a cubic significant relationship between elaidic acid content and heating time. At 190°C, there was a negative linear relationship between elaidic acid content and time of frying, while at 250°C, there was oscillatory relationship in the amounts of elaidic acid with time of heating. As a conclusion, all margarine and ghee samples analyzed in this study had elaidic acid before and after heat treatment used in the study. However, corn oil and olive oil were free from elaidic acid before and after studied heat treatments. Therefore, it is recommended to cook and bake with vegetable oils (such as corn oil) instead of solid fats, and to keep margarine and ghee consumption as low as possible in nutrition.Partial financial support for this study was obtained from the Dutch Nuffic through NICHE-PAA-233 project. HPLC analysis was done in Pharmacare PLC through the help of Mr. Ayman Qaddoumi
Effect of surfactant and surfactant blends on pseudoternary phase diagram behavior of newly synthesized palm kernel oil esters
Background: The purpose of this study was to select appropriate surfactants or blends of
surfactants to study the ternary phase diagram behavior of newly introduced palm kernel oil
esters.
Methods: Nonionic surfactant blends of Tween® and Tween®/Span® series were screened based
on their solubilization capacity with water for palm kernel oil esters. Tween® 80 and five blends
of Tween® 80/Span® 80 and Tween® 80/Span® 85 in the hydrophilic-lipophilic balance (HLB)
value range of 10.7–14.0 were selected to study the phase diagram behavior of palm kernel oil
esters using the water titration method at room temperature.
Results: High solubilization capacity was obtained by Tween® 80 compared with other surfactants
of Tween® series. High HLB blends of Tween® 80/Span® 85 and Tween® 80/Span® 80 at
HLB 13.7 and 13.9, respectively, have better solubilization capacity compared with the lower
HLB values of Tween® 80/Span® 80. All the selected blends of surfactants were formed as waterin-
oil microemulsions, and other dispersion systems varied in size and geometrical layout in the
triangles. The high solubilization capacity and larger areas of the water-in-oil microemulsion
systems were due to the structural similarity between the lipophilic tail of Tween® 80 and the
oleyl group of the palm kernel oil esters.
Conclusion: This study suggests that the phase diagram behavior of palm kernel oil esters,
water, and nonionic surfactants is not only affected by the HLB value, but also by the structural
similarity between palm kernel oil esters and the surfactant used. The information gathered in
this study is useful for researchers and manufacturers interested in using palm kernel oil esters
in pharmaceutical and cosmetic preparation. The use of palm kernel oil esters can improve drug
delivery and reduce the cost of cosmetics
Foreign Direct Investment in Post-Conflict Countries: The Case of Iraq's Oil and Electricity Sectors
Foreign direct investment is new phenomenon to Iraq, a post conflict country with abundance of natural resources. With dominant state-controlled public sector, attracting foreign investment is an added challenge to an economy devastated by years of wars. A qualitative case study was conducted to assess determinants of foreign direct investment in Iraq’s energy sector. Data was collected from interviews with business and government subject matter experts, and a review of publically available documents. Lack of security, political instability, corruption, and inadequate government policies towards foreign direct investment as symptoms found and typically shared by other post-conflict countries. The persistence of violence was not seen as a deterrent; however, foreign direct investment activity in the energy sector was virtually limited to the semi-autonomous region of Kurdistan. Investments were either wholly-owned or joint-venture enterprises. Implications to other post conflict countries, using Kuwait and Nigeria as illustrative examples, are presented and recommendations made.
Keywords: Foreign direct investment; Iraq; post-conflict country; energy
JEL Classifications: F21; F23; O53; P28
Formulation and in vitro release evaluation of newly synthesized palm kernel oil esters-based nanoemulsion delivery system for 30% ethanolic dried extract derived from local Phyllanthus urinaria for skin antiaging
Elrashid Saleh Mahdi1, Azmin Mohd Noor1, Mohamed Hameem Sakeena1, Ghassan Z Abdullah1, Muthanna F Abdulkarim1, Munavvar Abdul Sattar2 1Department of Pharmaceutical Technology, 2Department of Physiology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Pulau Pinang, Malaysia Background: Recently there has been a remarkable surge of interest about natural products and their applications in the cosmetic industry. Topical delivery of antioxidants from natural sources is one of the approaches used to reverse signs of skin aging. The aim of this research was to develop a nanoemulsion cream for topical delivery of 30% ethanolic extract derived from local Phyllanthus urinaria (P. urinaria) for skin antiaging. Methods: Palm kernel oil esters (PKOEs)-based nanoemulsions were loaded with P. urinaria extract using a spontaneous method and characterized with respect to particle size, zeta potential, and rheological properties. The release profile of the extract was evaluated using in vitro Franz diffusion cells from an artificial membrane and the antioxidant activity of the extract released was evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. Results: Formulation F12 consisted of wt/wt, 0.05% P. urinaria extract, 1% cetyl alcohol, 0.5% glyceryl monostearate, 12% PKOEs, and 27% Tween® 80/Span® 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and a 59.5% phosphate buffer system at pH 7.4. Formulation F36 was comprised of 0.05% P. urinaria extract, 1% cetyl alcohol, 1% glyceryl monostearate, 14% PKOEs, 28% Tween® 80/Span® 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and 56% phosphate buffer system at pH 7.4 with shear thinning and thixotropy. The droplet size of F12 and F36 was 30.74 nm and 35.71 nm, respectively, and their nanosizes were confirmed by transmission electron microscopy images. Thereafter, 51.30% and 51.02% of the loaded extract was released from F12 and F36 through an artificial cellulose membrane, scavenging 29.89% and 30.05% of DPPH radical activity, respectively. Conclusion: The P. urinaria extract was successfully incorporated into a PKOEs-based nanoemulsion delivery system. In vitro release of the extract from the formulations showed DPPH radical scavenging activity. These formulations can neutralize reactive oxygen species and counteract oxidative injury induced by ultraviolet radiation and thereby ameliorate skin aging. Keywords: nanoemulsions, Phyllanthus urinaria, skin antiaging, palm kernel oil ester
Effect of surfactant and surfactant blends on pseudoternary phase diagram behavior of newly synthesized palm kernel oil esters
Elrashid Saleh Mahdi1, Mohamed HF Sakeena1, Muthanna F Abdulkarim1, Ghassan Z Abdullah1,3, Munavvar Abdul Sattar2, Azmin Mohd Noor11Department of Pharmaceutical Technology, 2Department of Physiology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia; 3Department of Pharmaceutical Technology, International Medical University, Bukit Jalil, Kuala Lumpur, MalaysiaBackground: The purpose of this study was to select appropriate surfactants or blends of surfactants to study the ternary phase diagram behavior of newly introduced palm kernel oil esters.Methods: Nonionic surfactant blends of Tween® and Tween®/Span® series were screened based on their solubilization capacity with water for palm kernel oil esters. Tween® 80 and five blends of Tween® 80/Span® 80 and Tween® 80/Span® 85 in the hydrophilic-lipophilic balance (HLB) value range of 10.7–14.0 were selected to study the phase diagram behavior of palm kernel oil esters using the water titration method at room temperature.Results: High solubilization capacity was obtained by Tween® 80 compared with other surfactants of Tween® series. High HLB blends of Tween® 80/Span® 85 and Tween® 80/Span® 80 at HLB 13.7 and 13.9, respectively, have better solubilization capacity compared with the lower HLB values of Tween® 80/Span® 80. All the selected blends of surfactants were formed as water-in-oil microemulsions, and other dispersion systems varied in size and geometrical layout in the triangles. The high solubilization capacity and larger areas of the water-in-oil microemulsion systems were due to the structural similarity between the lipophilic tail of Tween® 80 and the oleyl group of the palm kernel oil esters.Conclusion: This study suggests that the phase diagram behavior of palm kernel oil esters, water, and nonionic surfactants is not only affected by the HLB value, but also by the structural similarity between palm kernel oil esters and the surfactant used. The information gathered in this study is useful for researchers and manufacturers interested in using palm kernel oil esters in pharmaceutical and cosmetic preparation. The use of palm kernel oil esters can improve drug delivery and reduce the cost of cosmetics.Keywords: phase diagram, palm kernel oil esters, nonionic surfactants, microemulsion
Carbopol 934, 940 and Ultrez 10 as viscosity modifiers of palm olein esters based nano-scaled emulsion containing ibuprofen
Micro-emulsions and sometimes nano-emulsions are well known candidates to deliver drugs locally. However, the poor rheological properties are marginally affecting their acceptance pharmaceutically. This work aimed to modify the poor flow properties of a nano-scaled emulsion comprising palm olein esters as the oil phase and ibuprofen as the active ingredient for topical delivery. Three Carbopol ® resins: 934, 940 and Ultrez 10, were utilized in various concentrations to achieve these goals. Moreover, phosphate buffer and triethanolamine solutions pH 7.4 were used as neutralizing agents to assess their effects on the gel-forming and swelling properties of Carbopol ® 940. The addition of these polymers caused the produced nano-scaled emulsion to show a dramatic droplets enlargement of the dispersed globules, increased intrinsic viscosity, consistent zeta potential and transparent-to-opaque change in appearance. These changes were relatively influenced by the type and the concentration of the resin used. Carbopol ® 940 and triethanolamine appeared to be superior in achieving the proposed tasks compared to other materials. The higher the pH of triethanolamine solution, the stronger the flow-modifying properties of Carbopol ® 940. Transmission electron microscopy confirmed the formation of a well-arranged gel network of Carbopol ® 940, which was the major cause for all realized changes. Later in vitro permeation studies showed a significant decrease in the drug penetration, thus further modification using 10% w/w menthol or limonene as permeation promoters was performed. This resulted in in vitro and in vivo pharmacodynamics properties that are comparably higher than the reference chosen for this study
The summer heat of cryptojacking season : Detecting cryptojacking using heatmap and fuzzy
Cryptojacking is a subset of cybercrime in which hackers use unauthorised devices (computers, smartphones, tablets, and even servers) to mine cryptocurrencies. Similar to many other forms of cybercrime, the objective of cryptojacking is achieve profit illegally. It is also designed to remain entirely concealed from the victim's view. However, its attacks continue to evolve and spread, and their number continues to rise. Therefore, it is essential to detect cryptojacking malware, as it poses a significant risk to users. However, in machine learning intelligence detection, an excessive number of insignificant features will diminish the detection's accuracy. For machine learning-based detection, it's important to find important features in a minimal amount of data. This study therefore proposes the Pearson correlation coefficient (PMCC), a measure of the linear relationship between all features. After that, this study employs the heatmap method to visualise the PMCC value as a colour version of heat. We utilised The Fuzzy Lattice Reasoning (FLR) classifier for classification algorithms in machine learning. This experiment utilised actual cryptojacking samples and achieved a 100 percent detection accuracy rate in simulation
Stability studies of nano-cream containing piroxicam
The aim of this study is to study the stability of the nano-cream formula containing the newly synthesized palm oil esters when stored for reasonable storage duration. The prepared 0.5% piroxicam nano-cream formula contained phosphate buffer as external phase, palm oil esters as the oil phase and a combination of (80:20) of Tween 80 and Span 20 as emulsifier at a ratio of 37:25:38, respectively. Piroxicam is a hydro-lipophobic drug. Stability on storage is an important aspect which ensures the dosage form can exert the effects it is supposed to exert for the duration of storage. Droplets size, electrical conductivity, drug content, pH and rheological parameters are the parameters that have been assessed under different temperature to evaluate the stability of nano-cream preparation. Thus, experiments which measure the above parameters were conducted at storage temperatures of 4, 25 and 40οC.The data obtained from the stability study conducted on nano-cream formula showed that this formulation was stable for the whole 3 months period of the study when stored at tested several temperatures.Keywords: Palm oil esters; Nonionic surfactant; Piroxicam; Nano-crea
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