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55% dari total keseluruhan pemakaian pelumas pembuangan di alam sekitar yang menyebabkan polusi pada lingkungan. Hal ini dapat mengatasi penggantiannya dengan biolubricant (biopelumas), karena murah, ramah lingkungan dan memiliki sifat pelumasan yang efektif. Tujuan dari penelitian ini adalah untuk memperoleh biopelumas dari PKO yang sesuai Standar Pelumas Mesran SAE 10W dan menentukan komposisi Asam Oleat : EGDE serta jumlah katalis dan suhu rekasi dengan keadaan yang optimal. Penelitian ini diawali dengan pembuatan FAME, lalu pembentukan EGDE dan proses sintesis biopelumas dengan variasi suhu 150°C, 160°C, 170°C, 180°C dan 190°C, jumlah katalis 2% dan 5% serta rasio mol Asam Oleat : EGDE 1:3 dan 1:5. Hasil penelitian ini diperoleh biopelumas dengan nilai densitas 0,8687 – 0,8886 gr/cm3, nilai viskositas kinematik 27,0948 – 28,0065 mm2/s, titik tuang 7 - 2°C dan berwarna kuning keemasan. Beberapa sudah memenuhi standar seperti warna, densitas dan viskositas kecuali titik tuang.

The hybrid nature and scope of contemporary conflicts, the terrorism threat, and the dramatic increase in competition for resources, global militarization and security challenges in Africa do not only carry the risk of state collapse, but have conditioned concerted efforts by national, regional and international actors to protect human rights and remedy the humanitarian situation. In many ways, the African continent with its unique and diverse nature of conflicts has become a platform for the renewal of the United Nations (UN) peacekeeping through the development of new operational and normative practices and strategies that, as a distinctive feature of the UN missions in the African continent, have gradually moved from the status of innovations to the category of quite commonplace global practice. This article attempts to assess UN peacekeeping in Africa from the 1960s till 2022. The authors examine the characteristics, nature and scope of peacekeeping operations (PKOs) as well as strategies for transforming peacekeeping mandates. Using a problem-chronological approach, comparative analysis and quantitative assessments of the UN peacekeeping missions, the formats of cooperation with regional organizations (the African Union (AU) and the Economic Community of West African States (ECOWAS)), gender composition of the UN missions, in particular, the authors come to the natural conclusion that the number of the UN peacekeeping operations and political missions in Africa remains high and their mandates have expanded and become more complex with increased activity of the leading world powers. The authors conclude that stabilization and conflict resolution in Africa will greatly depend on effective cooperation between the UN and regional organizations, as well as on the UN reforms and its ability to adapt rapidly to changing conflict scenarios in each African state.

In this study Design-Expert Software Version 11 was used to optimize the synthesis of a biolubricant through the transesterification of palm kernel oil (PKO) methyl ester and propane-1,2-diol, using potassium hydroxide (KOH) produced from Oil-Palm Empty Fruit Bunches (OPEFB). The OPEFBs were first pulverized into small bits, sun-dried, and burned. The resulting fine particles were soaked in distilled water. The concentration of the filtrate was determined by titration as 0.2 mol/dm³. The KOH produced was odourless, slightly yellow, and hygroscopic. Response surface methodology (RSM) using central composite design (CCD) was employed for the experiment design. The effects of temperature, molar ratio, and reaction time on the yield of biolubricant were evaluated. The predicted yield after process optimization was found to agree with the experimental value. The optimum conditions were obtained at a temperature of 100 °C, a molar ratio of 7:1, and a time of 200 min for a 96% biolubricant yield for PKO. Molar ratio and reaction time were found to be the most significant variables for PKO. The Analysis of Variance (ANOVA) implied that molar ratio and temperature were the most significant factors affecting the yield of biolubricant. [ABSTRACT FROM AUTHOR]

The disadvantages of the conventional cutting fluids such as mineral oil have prompted the search for eco-friendly cutting fluids. Vegetable oils have often been recommended as environmentally friendly substitutes for traditional mineral oil. The current study examined the performance of palm kernel oil (PKO) and its mineral oil during the turning of AISI 304 steel using the minimum quantity lubrication (MQL) technique. Six litres of crude PKO were extracted from palm kernel seeds through a mechanical extraction technique. Taguchi L _9 (3) ^3 orthogonal array was considered for the experiment. The depth of cut (DC), feed rate (FR), and spindle speed (SS) are the cutting parameters while cutting temperature (CT) and surface roughness (SR) are the response characteristics. Experimental results showed that the mineral oil outperformed the PKO in terms of SR with an improvement of 48.2%. The improvement of PKO over mineral oil is approximately 0.89% in terms of cutting temperature. The highest turning temperature of mineral oil was 67.333 °C, while that of PKO was 67.8 °C. In general, the performance of PKO shows it can be a good replacement for mineral oil if produced industrially with adequate additives. The grey relational analysis (GRA) showed that the optimum DC, FR, and SS for palm kernel and mineral oils are 1.25 mm, 0.25 mm rev ^−1 and 870 rev min ^−1 , and 1.25 mm, 0.10 mm rev ^−1 , and 870 rev min ^−1 , respectively. The results of this study demonstrated an experimental basis for the application of PKO minimal quantity lubrication turning and validated the efficacy of the integrated Taguchi-grey relational analysis (TGRA) optimization approach.

Threats were specified and in mass in the past, and then are transformed to multi-directional, multidimensional, and volatile structure in early 21st century. Hence uncertainty and instability dominate operational area. Today, security is comprehended solely not military but political, economic, lawful, psychological, and technological in a holistic approach. Towards this end, global security environment may be defined with three key words: circulation, complexity, and contingency. Within this context, aim of the mission is to enforce peace and restore stability by proactive measures. However, it seems impossible to have fruitful results in peace building operations by training 21st century people with a mindset of pre-Cold War time. Hence, the study aims at revealing the need for change in curriculum of officers to get deployed in peace building operations. The study, therefore, proposes a unified body taking on nationwide responsibility to manage training operations, and lays out relevant programs and tools to be included in curriculum.

Threats were specified and in mass in the past, and then are transformed to multi-directional, multidimensional, and volatile structure in early 21st century. Hence uncertainty and instability dominate operational area. Today, security is comprehended solely not military but political, economic, lawful, psychological, and technological in a holistic approach. Towards this end, global security environment may be defined with three key words: circulation, complexity, and contingency. Within this context, aim of the mission is to enforce peace and restore stability by proactive measures. However, it seems impossible to have fruitful results in peace building operations by training 21st century people with a mindset of pre-Cold War time. Hence, the study aims at revealing the need for change in curriculum of officers to get deployed in peace building operations. The study, therefore, proposes a unified body taking on nationwide responsibility to manage training operations, and lays out relevant programs and tools to be included in curriculum. [ABSTRACT FROM AUTHOR]

Ultrasonic spectrometry was used to monitor the changes in polymorphism of palm kernel fat present in two tempered non-dairy emulsions with different globule sizes. Laser diffraction and differential scanning calorimetry (DSC) were performed to characterize the emulsions. X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) were used to determine the polymorphic state and solid fat content (SFC) of fully hydrogenated palm kernel oil during tempering of the emulsions. The ultrasonic instrument generated a “chirp” signal, which is characterized by its bandwidth. The ultrasonic measurements were carried out using two different pairs of transducers with different center frequencies, 2.25 and 0.5 MHz, and bandwidths. 3D plots were generated disputing time, frequency, and signal strength. The whole tempering process, from start to finish, was better characterized with the 2.25-MHz center frequency transducers. The ultrasonic velocity through the emulsions was always higher for the more stable β′ polymorph than for the α polymorph (p < 0.05) regardless of the pair of transducers used. The 2.25-MHz transducer revealed no significant difference (p > 0.05) on the ultrasound velocities obtained for the two globule sizes. Monitoring of polymorphic changes in emulsions using ultrasonic spectrometry could be used for an online measurement system for industrial manufacturing. [ABSTRACT FROM AUTHOR]

We elaborated an alternative culture method, which we denominated PKO (initials in tribute of respect to Petroff, Kudoh and Ogawa), for isolating Mycobacterium tuberculosis from sputum for diagnosis of pulmonary tuberculosis (TB), and to compare its performance with the Swab and Petroff methods. For the technique validation, sputum samples from patients suspected of pulmonary TB cases were examined by acid-fast microscopy (direct and concentrated smear), PKO, Swab and Petroff methods. We found that Petroff and PKO methods have parity in the effectiveness of M. tuberculosis isolation. However, by the PKO method, 65% of isolated strains were detected in a period of £15 days, while by the Petroff method the best detection was in an interval of 16-29 days (71%). In positive smear samples, the average time of PKO isolation is only superior to the one related for Bactec 460TB. In conclusion, the exclusion of the neutralization stage of pH in the PKO reduces the manipulation of the samples, diminishes the execution time of the culture according to the Petroff method and facilitates the qualification of professionals involved in the laboratorial diagnosis of Tuberculosis.Foi elaborado um método de cultivo alternativo, denominado por nós PKO (iniciais referentes à Petroff, Kudoh e Ogawa), para o isolamento do Mycobacterium tuberculosis em amostras de escarro para o diagnóstico da tuberculose pulmonar (TB). Para validação da técnica, amostras de escarro de pacientes suspeitos de TB foram submetidas aos métodos de baciloscopia (direta e pós-concentração), PKO, Swab e Petroff. A análise comparativa entre o método de Petroff e o PKO mostrou paridade de resultados em relação ao isolamento e número de colônias de M. tuberculosis. Porém, pelo método PKO, 65% das cepas isoladas foi detectada em um período £15 dias, enquanto que pelo método de Petroff a melhor detecção ocorreu em um intervalo de 16-29 dias (71%). O tempo médio de isolamento pelo PKO é somente superior ao sistema comercial Bactec 460TB em amostras positivas na baciloscopia. A exclusão da etapa de neutralização de pH no método PKO reduz a manipulação das amostras, diminui o tempo de execução do cultivo em relação ao de Petroff e facilita o treinamento de profissionais que realizam o diagnóstico laboratorial da TB.

The article discusses United Nations (UN) peacekeeping forces, providing a brief overview of their history and analyzing their use in the 21st century. It offers a Russian perspective on the issues involved, including topics such as the extent of Russian contributions to the peacekeeping forces, and their involvement in volatile regions such as the Middle East, Africa, and the Balkans. Although the UN has been unable to prevent many cases of genocide and ethnic cleansing, its attempts to do so are lauded.

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Based on the difference between the speed of sound in solids and liquids, an ultrasonic velocity technique was employed to monitor the phase transition, nucleation and crystal growth of two palm oils dispersed as oil-in-water (O/W) emulsions. The O/W emulsions of palm mid-fraction (PMF) and palm kernel oil (PKO) crystallized at 12 and 0 °C, respectively. The degree of supercooling of PMF emulsion was 18 °C, while that of PKO emulsion was 28 °C. The effects of different hydrophobic emulsifier additives on the interfacial heterogeneous nucleation, induced at the oil/water interface of emulsion droplets, and crystal growth were studied by monitoring the sound velocity (V) during isothermal crystallization. Sucrose oligoesters (SOEs) having stearic (S-170) and palmitic (P-170) fatty acid chains accelerated nucleation, yet SOEs having short chains such as lauric (L-170) showed no effect in the two fats. A polyglycerine ester (DAS-750) had a lesser and different effect on the nucleation of PKO compared to PMF. Moreover, the crystal growth was retarded in the two oils at different degrees by the addition of S-170. Solubility measurements indicated that the solubility degree of DAS-750 was more than that of S-170. In addition, the solubility of DAS-750 was higher in PKO than in PMF. The effects of the additives were thus discussed in terms of their molecular structure in relation to the oil phase composition. [Copyright &y& Elsevier]

Background & Aims: Biliary atresia represents obstructive cholangiopathy in infants progressing rapidly to cirrhosis and end-stage liver disease. Activated NK cells expressing Nkg2d have been linked to bile duct injury and obstruction by establishing contact with cholangiocytes. To define the mechanisms used by cytotoxic cells, we investigated the role of perforin and granzymes in a neonatal mouse model of rotavirus (RRV)-induced biliary atresia., Methods: We used complementary cell lysis assays, flow cytometric analyses, quantitative PCRs and in vivo systems to determine the mechanisms of bile duct epithelial injury and the control of the tissue phenotype in experimental biliary atresia., Results: RRV-infected hepatic NK and CD8 T cells increased the expression of perforin and injured cholangiocytes in short-term culture in a perforin-dependent fashion. However, the loss of perforin in vivo delayed but did not prevent the obstruction of bile ducts. Based on the increased expression of granzymes by perforin-deficient cytotoxic cells in long-term cytolytic assays, we found that the inhibition of granzymes by nafamostat mesilate (FUT-175) blocked cholangiocyte lysis. Administration of FUT-175 to perforin-deficient mice after RRV infection decreased the development of jaundice, minimized epithelial injury, and improved long-term survival. However, the inhibition of granzymes alone in wild-type mice was not sufficient to prevent the atresia phenotype in newborn mice. In infants with biliary atresia, hepatic Granzymes A and B mRNA, but not Perforin, increased at the time of portoenterostomy., Conclusions: Perforin and granzymes have complementary roles mediating epithelial injury by NK and CD8 T cells. The prevention of experimental biliary atresia can only be achieved by inhibiting both granules., (Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)