Synthesis of g-Al2O3 from Tatakan, South Kalimantan kaolin using simple methods: metakaolinization, dealumination, precipitation process using polyethylene glycol (PEG-6000) as a structure directing ...agent, calcination steps, and characterization of its products have been presented. The purified kaolin was metakaolinized and dealuminated to get amorphous aluminum hydroxide. After that, the sample was precipitated using the various concentration of PEG and NH4OH as the precipitating agent. Calcination process was carried out at calcined at a temperature of 700°C for 3 hours. Based on the FTIR spectra and X-ray diffraction of the g-Al2O3 obtained was similar to that of commercial g-Al2O3. The highest crystallinity of g-Al2O3 was formed when using twice of critical micelle concentration of PEG (10-3 mol/L). This simple process is an industrially practicable substitute to the Bayer process
Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi dan lama perendaman polietilen glikol (PEG) secara interaksi maupun masing-masing faktor utama terhadap viabilitas, vigor dan produksi ...benih kedelai. Penelitian dilaksanakan di Kebun Percobaan, Fakultas Pertanian, Universitas Islam Riau, Desember 2015 sampai April 2016. Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap Faktorial 4 x 4 dengan 3 ulangan. Faktor pertama adalah konsentrasi PEG terdiri atas 4 taraf : 0,0; 2,5; 5,0 dan 7,5%. Faktor kedua adalah lama perendaman juga terdiri atas 4 taraf : 2; 4; 6 dan 8 jam. Parameter yang diamati yaitu daya kecambah, kecepatan tumbuh, indeks vigor, panjang plumule, panjang akar, jumlah polong berisi penuh dan bobot biji kering per tanaman. Hasil pengamatan dianalisis secara statistik dengan menggunakan analisis ragam dan bila berpengaruh nyata, diuji lanjut dengan menggunakan uji BNJ pada taraf 5%. Hasil penelitian menunjukkan konsentrasi PEG dan lama perendaman berpengaruh nyata terhadap daya kecambah, kecepatan tumbuh, indeks vigor, panjang plumule, panjang akar, jumlah polong berisi penuh dan bobot biji kering per tanaman. Kombinasi taraf faktor terbaik adalah konsentrasi PEG 7,5% dan lama perendaman 6 jam.
Bahan plastik biodegradable saat ini sedang populer dikembangkan untuk menggantikan plastik kemasan konvensional yang tidak ramah lingkungan. Penelitian ini bertujuan untuk mengetahui pengaruh ...penambahan polietilen glikol (PEG) terhadap karakteristik film berbahan dasar k-karaginan. k-karaginan yang digunakan dalam formulasi pembuatan film yaitu sebanyak 1,5% (b/v), sedangkan konsentrasi PEG yang ditambahkan bervariasi yaitu 2, 4, 6, 8, dan 10 % (b/b). Larutan dipanaskan hingga suhu 85 oC kemudian dicetak dalam bentuk film tipis, lalu didinginkan dan dikeringkan dengan oven hingga didapatkan berat konstan. Film yang diperoleh kemudian dilakukan analisis termal, kuat tarik, elongasi dan water vapor transmission rate (WVTR). Hasil penelitian menunjukkan bahwa semakin besar polietilen glikol yang ditambahkan pada film karaginan dapat meningkatkan titik leleh dan entalpi, tetapi menurunkan nilai kuat tariknya, dan juga tidak mempengaruhi nilai WVTR. Penambahan PEG sampai konsentrasi 4% juga meningkatkan nilai elongasi film. Dari hasil pengujian diperoleh jumlah optimal penambahan PEG yaitu sebesar 4% dengan nilai kuat tarik sebesar 0,86±0,16MPa, elongasi 25,40±6,64%, dan WVTR 116,02±8,00 g/m2/24 jam.
Abstract
Objective
Macroprolactinemia is an important cause of hyperprolactinemia. The aim of this study was to examine the added value of the consideration of modified reference range in ...determination of macroprolactinemia and true hyperprolactinemia.
Materials and methods
Three hundred and ninety patients with high and 131 with normal prolactin (PRL) levels were included in this study. PRL had been analyzed before and after polyethylene glycol precipitation (post-PEG PRL). Recovery percentage (R%) <40% and >60% had been reported as macroprolactinemia and true hyperprolactinemia, respectively. Post-PEG PRL levels were evaluated according to the modified reference range obtained from those of the normoprolactinemic subjects.
Results
According to the R% criterion; macroprolactinemia had been detected in 24.9% and true hyperprolactinemia in 67.4% of hyperprolactinemic patients. When the data were evaluated considering the post-PEG PRL levels according to the modified reference range; 13 (13.4%) of the 97 macroprolactinemia reports would be considered as true hyperprolactinemia and 6 (2.3%) of the 263 true hyperprolactinemia reports would be changed as macroprolactinemia.
Conclusion
Discrimination capacity of R% criterion for true hyperprolactinemia and macroprolactinemia is limited, and we suggest that, in accordance with R% criterion, laboratory reports should include the post-PEG PRL levels along with the modified reference range.
Abstract
Objective
Resveratrol (RSV) has therapeutic potential with several biological activity. The aim of this study was to develop organogel formulations of RSV and to investigate the ...proliferation and migration via in vitro wound model of primary normal human skin fibroblasts (NHDF).
Methods
The optimum RSV concentration was determined by MTT assay. Three different types of polyethylene glycol (200, 400 and 600) were used to prepare Carbopol 940 based organogels by micro-irradiation method. Differential scanning microscopy (DSC) and rheological analyses were conducted. Proliferation activity and migration of fibroblast cells were determined with the Giemsa staining.
Results
The percentage of migration rate obtained with RSV-PEG-400 organogel was the highest, as 59.7%. The values obtained with RSV-PEG-200 and RSV-PEG-600 were 36.6% and 48.7%, respectively.
Conclusion
This study showed that RSV organogels produced by micro-irradiation method could be a model for active molecules that have low water solubility for different applications as pharmaceuticals, and cosmeceuticals.
Abstract
Objective
Macroprolactinemia detection is important to avoid unneccessary tests and overtreatment. High prolactin levels require routine screening and clinicians must be aware of ...macroprolactinemia frequency encountered with the method in use. In this study we aimed to determine the macroprolactinemia rate in our laboratory.
Methods
Prolactin results of different patients analysed on two different immunoassay systems within two consecutive years were evaluated. Analyses were performed on Beckman Coulter UniCel
®
DxI800 and Roche Cobas
®
e601 immunoassay systems. Samples for macroprolactin analysis were precipitated using polyethylene glycol (PEG) 6000. Post-PEG recovery <40% was defined as positive, 40–60% as gray-zone and >60% as negative for macroprolactin.
Results
For the samples analysed on DxI800 (n=14,958) hyperprolactinemia frequency was 8.1% (n=1208). One of 138 samples submitted for macroprolactin analysis was positive, while three of them were in the gray-zone. For the samples analysed on Cobas
®
e601 (n=14,040) hyperprolactinemia frequency was 13.9% (n=1954). Eighteen of 238 samples submitted for macroprolactin analysis were positive, while 21 of them were in the gray-zone.
Conclusion
A difference was found between two immunoassay systems used in our laboratory in terms of macroprolactinemia rate. However, inability of simultaneous analyses on both systems, lack of evaluation with gel filtration chromatography, and heterophile antibody blocking tube were the limitations.
The objective of the present work was to improve the dissolution properties of the poorly water-soluble drug meloxicam by preparing solid dispersions with hydroxyethyl cellulose (HEC), mannitol and ...polyethylene glycol (PEG) 4000 and to develop a dosage form for geriatric population. Differential scanning calorimetry, X-ray diffractometry, Fourier transform infrared spectroscopy and scanning electron microscopy were used to investigate the solid-state physical structure of the prepared solid dispersions. Higher in vitro dissolution of solid dispersions was recorded compared to their corresponding physical mixtures and the pure drug. PEG 4000 in 1: 9 drug to carrier ratio exhibited the highest drug release (100.2%), followed by mannitol (98.2%) and HEC (89.5%) in the same ratio. Meloxicam-PEG 4000 solid dispersion was formulated into suspension and optimization was carried out by 23 factorial design. Formulations containing higher levels of methyl cellulose and higher levels of either sodium citrate or Tween 80 exhibited the highest drug release.
Cilj rada bio je poboljšati topljivost meloksikama u vodi pripravom čvrstih disperzija s hidroksietilcelulozom (HEC), manitolom i polietilen glikolom 4000 (PEG 4000) te razviti dozirani pripravak za gerijatrijsku populaciju. Za ispitivanje fizičke strukture pripravljenih čvrstih disperzija korištene su diferencijalna pretražna kalorimetrija, difraktometrija rentgentskim zrakama, FTIR i pretražna elektronska mikroskopija. Čvrste disperzije su u in vitro uvjetima pokazale bolju topljivost u odnosu na fizičku smjesu i čistu ljekovitu tvar. Najbolje oslobađanje lijeka (100,2%). Postignuto je iz disperzija s PEG 4000 (omjer ljekovite tvari i nosača 1:9). Slijede manitol (98,2%) i HEC (89,5%) (isti omjer meloksikama i polimera). Čvrsta disperzija meloksikama s PEG 4000 prevedena je u suspenziju te optimirana 23 faktorijalnim dizajnom. Najbolje oslobađanje ljekovite tvari postignuto je iz pripravaka koji sadrže veći udio etilceluloze i natrijevog citrata, odnosno Tween 80.
An important aspect of salt tolerance studies in different plants is the relationship between salt and water stress.
In the present study calluses (60 days old) of 2 sugarcane cultivars (cv. SPF 234 ...and cv. HSF 240) were treated with 4
different salt concentrations, including a control (0 mM NaCl), after 1% polyethylene glycol (PEG) pretreatment for 5
days. Fresh weight, callus browning, and necrosis data were recorded at day 120. Biochemical parameters (soluble protein
contents, and peroxidase, catalase, and superoxide dismutase activity) were also analysed. Regardless of PEG pretreatment,
calluses subjected to salt stress had less fresh weight than the control; however, less necrosis was observed in PEG pretreated
callus cultures than in non-pretreated cultures subjected to the same salt concentration. PEG pretreatment
enhanced the biosynthesis of soluble protein contents. Likewise, a general increase was observed in antioxidant enzyme
activity in the PEG-pretreated callus cultures, as compared to the non-pretreated controls exposed to the same salt
concentration. PEG pretreatment also increased the regeneration potential of the callus cultures of both sugarcane
cultivars after NaCl treatment. These results suggest that PEG pretreatment could improve salt tolerance in these 2
sugarcane cultivars.
Sedamdesetih godina prošlog stoljeća u Arheološkom muzeju Zadar prvi put je na ovim prostorima provedena konzervacija mokrog drva. Konzervirana su dva ranohrvatska broda tipa Condura Croatica iz Nina ...otopinom polietilen-glikola. Istraživanjem antičke luke Enone (Nina) pronađeni su i izvađeni ostatci dvaju antičkih šivanih brodova tipa serilia. Ti su brodovi jedinstveni jer su izrađeni bez metalnih dijelova. Naime, svi dijelovi broda spojeni su šivanjem, a korišteni su samo konopci i drveni klinovi. Prvi brod konzerviran je neposredno nakon vađenja 1979. godine, a drugi je izvađen 1987. godine. Spletom okolnosti ostao je nekonzerviran dugi niz godina. Nastavljajući tradiciju, ponovno je pokrenuta konzervacija mokrog drva istom metodom. U tu svrhu izrađen je novi sustav zagrijavanja bazena toplovodnom grijalicom. U radu je opisana konzervacija broda. Dat je kratak osvrt na metodu konzervacije otopinom polietilen-glikola te je detaljno opisan sustav zagrijavanja bazena toplovodnom grijalicom.
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