Ethylene Glycol Treatment Research Articles

MINERALOGICAL PROPERTIES OF OAK FOREST SOILS IN IRAQI KURDISTAN REGION

This experiment was conducted from 1/7/2016 to 20/12/2018 to study the mineralogical properties of oak forest at 12 locations (Gara, Matin and Brifca) from Dohuk governorate, (Bilah, Malakan and Awagrd) from Hawler Governorate, (Bardanga, Badawan and Chwarta) from Sulaimani Governorate, and (Bakhakon, Hawar and Sartak) from Halabja governorate in Iraqi Kurdistan region. The samples collected from a depth of (0 – 60) cm for laboratory analysis. The study includes qualitative identification of clay minerals by X- ray diffraction data. Peak height was used as a rough indicator of relative abundance of minerals. In general, the expansion of 14°A to ≈ 17°A in ethylene glycol treatment was not detected because the measuring was started from 5θ (degree 5 theta) so the differentiation between Chlorite and Semectite was not done in this treatment. The main results indicated that the swelling chlorite being the dominant mineral in these soils. While the miner clay mineral in that locations were Kaolinite. Mica was identified in all location except of Bilah site, the dominant type of Mica was Muscovite which was obtained from 6 Locations, while Biotite obtained from 5 sites. It appears that Muscovite was recorded from 50% of Forest sites while Biotite recorded at 41.7% of Forest sites and Both Mica mineral type was not recorded from 8.3% of studied Forest soils.

Macroscopic Modeling of Water Uptake Behavior of PEDOT:PSS Films.

Poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) is a widely used conductive polymer (CP) for applications in electronic devices. In the context of transparent electrodes or soft actuators, the uptake of water by PEDOT:PSS is an essential element in the performance of the physical system. We study the water uptake of pure films and films treated with ethylene glycol (EG) commonly used to enhance the electrical properties of PEDOT:PSS. Gravimetric analysis was used to investigate the water sorption–desorption of PEDOT:PSS and its change with the EG treatment for a wide range of configurations (thickness, temperature, and relative humidity). We demonstrate that a simple Fickian model cannot correctly represent the experimental results; we therefore introduce a fully coupled reaction–diffusion scheme. This model describes the transport of diffusing molecules into the polymer film, taking into account, in addition to the classical diffusion mechanism, the reaction between the reactive sites of the polymer network and the water molecules. We demonstrate that solvent treatments have a direct influence on the kinetics of the water uptake of PEDOT:PSS films in terms of diffusivity, solubility, and rate of reaction. The proposed model can be used to accurately predict the water uptake of CP films in the case of complex three-dimensional configurations that are needed for the design of complex actuators.

Enhancement of conductivity and transmittance of graphene oxide/PEDOT:PSS electrodes and the evaluation of charge transfer dynamics

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), PEDOT:PSS, is a polymeric composite that can substitute indium tin oxide (ITO), enabling ITO-free organic devices. However, PEDOT:PSS films have conductivities two orders of magnitude lower than ITO due to the presence of PSS, an insulator polymer added to provide water dispersion to PEDOT. To enhance the electrical performance of the films and overcome the insulator limitations, we prepared thin films of graphene oxide (GO) and PEDOT:PSS composites. The dried films were then treated with ethylene glycol (EG). An increment of two orders of magnitude in conductivity values was observed, as well as an increase in transmittance at the visible region. Also, GO:PEDOT:PSS thin films became more hydrophobic due to the partial removal of PSS. The mass ratio that is equal to 0.058 of GO/PEDOT provides higher electrical conductivity due to higher chain orientation of PEDOT as seen in the near edge X-ray absorption fine structure and resonant Auger spectroscopy measurements. The electrical transport follows the Mott Variable Range Hopping model for low temperature, showing that the conduction occurs in three dimensions. The solvent treatment increases the characteristic conductivity and decreases the activation hopping energy, with the characteristic temperature remaining almost unchanged. It indicates that the EG treatment promotes a decrease in charge transfer time and resistivity.

The Protective Effect of Pomegranate and Lemon Juices in Number of Biochemical Parameters in Blood Serum and Tissue of Local Rabbits Infected by Experimental Urolithiasis

The aim of this study is to determine the protective effect of both pomegranate juice Punica granatum and Citrus juice Citrus limon in preventing the newly formed kidney stone induced by ethylene glycol in local male rabbits Oryctolagus cuniculus,which was expressed by monitoring renal functions, study of the effect of oxidative stress induced by ethylene-glycol, in addition to microscopic examination of the kidney tissue. In the current study 30 male rabbits were used ranging in age from (8-10) months, and weight (1500 - 2000) g, divided into 6 random groups, 5 Rabbit / group, as follows:The first group : was given water and the standard diet as a control group, Group 2: was given ethylene glycol at a concentration of 1 ml / kg body weight, Group 3: was given the Pomegranate juice with a concentration of 6 ml / kg body weight, Group 4: was given the lemon juice at a concentration of 4 ml / kg body weight, Group 5: was given the ethylene glycol at a concentration of 1 ml / kg in addition to Pomegranate juice with a concentration of 6 ml / kg body weight, Group 6: was given the ethylene-glycol at a concentration of 1 ml / kg body weight as well as lemon juice at a concentration of 4 ml / kg body weight, for 30 days and two doses daily in the morning and evening. Results showed the induction of calculi by ethylene glycol in local male rabbits which resulted in negative effects in the biochemical parameters, which was a significant increase at a potential level (P≤ 0.05) in the concentration of urea, creatinine, uric acid, malodialdehyde MDA, magnesium, potassium while the concentration of glutathione GSH and calcium decreased when treated with ethylene glycol compared with control, Tissue sections of the kidney showed a clear deposition of calcium oxalate crystals in renal tissues with a damage of the epithelial tissue lining of the renal tubules with necrosis, degeneration and enlargement of renal tubules due to deposition of these crystals. The treatment of local male rabbits with pomegranate and lemon juice each alone lead to positive effects in biochemical parameters for kidney, the results also showed a non significant decrease in the level of glutathione and a significant decrease in level of blood serum MDA compared with control. Treatment of ethylene glycol with pomegranate and lemon juices alone lead to positive effects in biochemical parameters and studied electrolytes. Tissue sections of the kidney showed decrease in deposition of calcium oxalate crystals in the renal tubules and the damage caused by ethylene glycol in epithelial tissue lining of the kidney.

미생물 고정화 담체를 이용한 ethylene glycol의 생물학적 처리

미생물 고정화 담체를 이용한 ethylene glycol의 생물학적 처리

A non-traditional approach to cryopreservation by ultra-rapid cooling for human mesenchymal stem cells

Cryopreservation is the most common method for long-term cell storage. Successful cryopreservation of cells depends on optimal freezing conditions, freezer storage and a proper thawing technique to minimize the cellular damage that can occur during the cryopreservation process. These factors are especially critical for sensitive stem cells with a consequential and significant impact on viability and functionality. Until now, slow-freezing has been the routine method of cryopreservation but, more recently rapid-cooling techniques have also been proposed. In this study, an ultra-rapid cooling technique [1] was performed for the first time on human mesenchymal stem cells and the effectiveness evaluated in comparison with the conventional slow-freezing procedure. A thin nylon-membrane carrier was used combined with different cryoprotective agents: dimethyl sulfoxide, ethylene glycol and/or trehalose. Various aspects of the low cryoprotective doses and the ultra-rapid cooling procedure of the human mesenchymal stem cells were examined including: the physical properties of the nylon-support, cells encumbrance, viability, proliferation and differentiation. The expression of cell surface markers and apoptosis were also investigated. The study used an ultra-rapid cooling/warming method and showed an overall cell integrity preservation (83–99%), with no significant differences between dimethyl sulfoxide or ethylene glycol treatment (83–87%) and a substantial cell viability of 68% and 51%, respectively. We confirmed a discrepancy also observed by other authors in cell viability and integrity, which implies that caution is necessary when assessing and reporting cell viability data.

Antiurolithiatic effect of ferulic acid on ethylene glycolinduced renal calculus in experimental rats

Purpose : To evaluate the anti-urolithiatic effect of ferulic acid on ethylene glycol-induced kidney stone in a rat model. Methods : Five groups of adult male Sprague-Dawley rats (6 rats/group) were used in this study. Group I rats served as normal control. Renal calculus was induced through ethylene glycol (0.75 % v/v in drinking water) administration to all rats for 28 days except those in group 1. Prior to ethylene glycol treatment, ferulic acid was given orally (gavage) to rats in groups III and IV at doses of 40 and 80 mg/kg, respectively. Rats in group V (positive control) were treated with standard drug, cystone at a dose of 750 mg/kg prior to ethylene glycol administration, while group II rats received no treatment. Kidney tissue and blood serum were sampled after 28 days and used for biochemical and histopathological analyses. Results : Rats in group II showed significant increases in oxidative stress pattern as seen in significant reductions in GSH, SOD, GPx, and CAT levels, and significant elevation of lipid peroxidation (LPO), relative to normal control group (p < 0.05). However, renal calculus formation and oxidative stress were significantly inhibited by ferulic acid treatment in groups III and IV. These results were supported by histopathological findings. Conclusion : Ferulic acid exerts anti-urolithiatic effect via inhibition of oxidative stress. Thus, it has potentials for use in preventing kidney stone formation. Keywords : Urolithiasis, Ferulic acid, Ethylene glycol, Kidney, Histopathology

Highly Conducting, Transparent PEDOT:PSS Polymer Electrodes from Post‐Treatment with Weak and Strong Acids

AbstractThe origin of high conductivity in polymer electrodes based on poly(3,4‐ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is investigated and the resilience against water exposure is tested. Post‐treatment with weak and strong acids, namely, hydrochloric acid (HCl), formic acid (HCOOH), nitric acid (HNO3), and sulfuric acid (H2SO4), is performed and compared to the commonly used ethylene glycol treatment. PEDOT:PSS electrodes with electrical conductivities of up to ≈3000 S cm−1 and high transmittance are obtained. The underlying mechanisms for enhanced conductivity are elucidated by means of electrical (4‐point probe), optical (UV‐Vis spectroscopy), compositional (X‐ray photo‐electron spectroscopy), and structural (grazing‐incidence wide‐angle X‐ray scattering, GIWAXS) characterizations. Selective PSS removal and structural rearrangement of PEDOT‐rich domains due to an enhanced lamellar stacking is identified as major influence on the improvement in electrical conductivity. This beneficial high order is evidenced via additional signals in the GIWAXS patterns, which are altered by subsequent H2O treatment. The PSS removal and structural rearrangement is linked to the acids' strength and dielectric constant. High conductivities are reached by efficient PSS removal via HNO3 or H2SO4 treatment with the drawback of high sensitivity against H2O. By contrast, HCl and HCOOH treatment obtaining a medium enhanced conductivity differ in the amount of PSS removal but show higher H2O resistance.

Endothelium corneum gigeriae galli extract inhibits calcium oxalate formation and exerts anti-urolithic effects

Ethnopharmacological relevanceTraditional Chinese Medicine is preferred because of its safety and minimal/reduced side effects. Endothelium Corneum Gigeriae Galli (ECGG) extract, a traditional Chinese drug consisting of the dried gizzard membrane of Gallus gallus domesticus Brisson, was assessed for its effects and mechanism on urolithiasis. Aims of studyTo evaluate the effects of ECGG extract on calcium oxalate (CaOx) crystal formation in vitro, and assess the anti-urolithic effects of ECGG extract in vivo and explore the underlying mechanism. Materials and methodsIn vitro, CaOx crystals were treated with ECGG extract (0.05, 0.2, and 0.8 g/mL), and assessed by scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray powder diffraction and electrical conductivity. Then, a rat model of renal calculi was established by ethylene glycol and ammonium chloride treatment, and ECGG extract (5.0, 10.0 and 20.0 g/kg) was administered orally. After treatment, urine, serum and kidney bioindicators were analyzed, as well as kidney's pathological features. ResultsIn the presence of ECGG extract, calcium oxalate dihydrate (COD) crystals with typical tetragonal bipyramidal morphology were obtained; meanwhile, the formation of calcium oxalate monohydrate (COM), a major urinary stone component, was inhibited; in addition, the equilibration time of the chemical reaction of Ca2+ and C2O42− ions was delayed in a concentration dependent manner. ECGG extract actually showed anti-urolithic effects; the incidence rates of crystal formation in the kidney in the model, low, middle and high dose groups were 100%, 90%, 70% and 60%, respectively, with a dose-dependent alleviation of kidney stone amounts and kidney damage. Treatment with middle and high ECGG extract doses significantly decreased urine uric acid and oxalic acid amounts, serum creatinine, urea nitrogen and uric acid contents, and kidney tissue oxalic acid and calcium levels, while increasing kidney and urinary magnesium and superoxide dismutase levels (P < 0.05). ConclusionECGG extract has outstanding anti-urolithic effects, potentially with included bioorganic molecules inducing COD crystal nucleation and growth. Therefore, ECGG extract is a promising drug for preventing and treating urolithiasis.

Antilithiatic and diuretic activity of Cucurbita moschata on ethylene glycol induced lithiasis in male albino Wistar rats

A detailed investigation on the antilithiatic and diuretic activity of ethanolic extract of seeds and fruit of Cucurbita moschata was undertaken to find the pharmacological basis for the ethnomedicinal use. The ethanolic extract was evaluated for its inhibitory potential on lithiasis (stone formation), induced by oral administration of 0.75% ethylene glycolated water to adult male albino Wistar rats for 28 days. The ethanolic extract significantly reduced the elevated levels of crucial urinary ions, viz. calcium, oxalate, and phosphate and also significantly reduced the increased deposition of stone forming constituents in the kidney of calculogenic rats. The high serum creatinine level observed in ethylene glycol-treated rats was also reduced, following treatment with the extract. The diuretic activity of Cucurbita moschata extract at the dosage of 200 mg/kg and 400 mg/kg was compared with standard drug Furosemide at the dosage of 20 mg/kg by determination of urine volume, its sodium and potassium concentrations. The extract exhibited significant diuretic activity in rats. All the observations under study provided the basis for the conclusion that seed and fruit extract of Cucurbita moschata inhibits stone formation induced by ethylene glycol treatment and also have significant diuretic activity.

Generating Power Enhancement of Flexible PVDF Generator by Incorporation of CNTs and Surface Treatment of PEDOT:PSS Electrodes

AbstractTwo approaches are proposed for enhancing the generating power of polyvinylidene fluoride (PVDF) flexible generator by incorporating carbon nanotubes (CNTs) and ethylene glycol (EG) treatment of the poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) electrodes. By incorporating CNTs into the PVDF polymer, higher portion of β‐phase PVDF can be obtained, which shows higher piezoelectricity resulting in higher electric charge generating performance. Higher conductivity is also obtained by surface treatment of the PEDOT:PSS electrodes using EG solvent due to the removal of excess PSS in the electrodes. Highly conductive electrode makes effective mobility of charges generated from the CNT/PVDF film, resulting in higher generating performance. Consequently, higher generating performance can be achieved by collaborating the above two approaches.

Toward Stretchable Self‐Powered Sensors Based on the Thermoelectric Response of PEDOT:PSS/Polyurethane Blends

AbstractThe development of new flexible and stretchable sensors addresses the demands of upcoming application fields like internet‐of‐things, soft robotics, and health/structure monitoring. However, finding a reliable and robust power source to operate these devices, particularly in off‐the‐grid, maintenance‐free applications, still poses a great challenge. The exploitation of ubiquitous temperature gradients, as the source of energy, can become a practical solution, since the recent discovery of the outstanding thermoelectric properties of a conductive polymer, poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS). Unfortunately the use of PEDOT:PSS is currently constrained by its brittleness and limited processability. Herein, PEDOT:PSS is blended with a commercial elastomeric polyurethane (Lycra), to obtain tough and processable self‐standing films. A remarkable strain‐at‐break of ≈700% is achieved for blends with 90 wt% Lycra, after ethylene glycol treatment, without affecting the Seebeck voltage. For the first time the viability of these novel blends as stretchable self‐powered sensors is demonstrated.

Solid-State Fluorescence of Fluorine-Modified Carbon Nanodots Aggregates Triggered by Poly(ethylene glycol).

Solid-state fluorescent carbon quantum dots (QDs) can be used for the encryption of security information. Controlling the dispersion and aggregation of the QDs is crucial for switching their solid-state fluorescence "on" and "off." The use of polymers has been proposed to slightly separate the QDs inside aggregates to trigger their fluorescence. However, the complex interactions between the QDs and flexible polymer chains make this process challenging. Here, fluorine-modified carbon nanodots (FCDs) were used in a solution as the printing ink. After printing, the FCDs were aggregated on paper via hydrogen bonds, thereby quenching the fluorescence. After a poly(ethylene glycol) (PEG) treatment, the FCDs exhibited yellow solid-state fluorescence due to an increased interdot spacing. The fluorescence intensity and emission wavelength could be tuned by varying the molecular weight and quantity of PEG used. Finally, we demonstrated a high-resolution encryption and decryption system based on the PEG-triggered fluorescence of FCDs.

SaRNA-mediated activation of TRPV5 reduces renal calcium oxalate deposition in rat via decreasing urinary calcium excretion.

Hypercalciuria is a main risk factor for kidneystone formation. TRPV5is the gatekeeper protein for mediating calcium transport and reabsorption in the kidney. In the present study, we tested the effect of TRPV5 activation with small activating RNA (saRNA), which could induce gene expression by targeting the promoter of the gene, on ethylene glycol (EG)-induced calcium oxalate (CaOx) crystals formation in rat kidney. Five pairs of RNA activation sequences targeting the promoter of rat TRPV5 were designed and synthesized. The synthesized saRNA with the strongest activating effect was selected, and transcellular calcium transportation was tested by Fura-2 analysis. Subsequently, Sprague-Dawley rats were equally divided into three groups and fed with water, 1% EG for 28days after injecting the negative control saRNA, 1% EG for 28days after injecting the selected TRPV5-saRNA, respectively. The CaOx crystal formation and the 24-h urine components were assessed. In vitro study, saRNA ds-320 could significantly activate the expression of TRPV5 and transcellular calcium transportation. In vivo study, after 28days treatment of EG, rats pre-infected with saRNA ds-320 had lower urinary calcium excretion and renal CaOx crystals formation as compared to that pre-infected with negative control saRNA. Activation of TRVP5 with saRNA ds-320 could inhibit EG-induced calcium oxalate crystals formation via promoting urine calcium reabsorption and decreasing urine calcium excretion in rats.

Prediction and validation of the duration of hemodialysis sessions for the treatment of acute ethylene glycol poisoning

The duration of hemodialysis (HD) sessions for the treatment of acute ethylene glycol poisoning is dependent on concentration, the operational parameters used during HD, and the presence and severity of metabolic acidosis. Ethylene glycol assays are not readily available, potentially leading to undue extension or premature termination of HD. We report a prediction model for the duration of high-efficiency HD sessions based retrospectively on a cohort study of 26 cases of acute ethylene glycol poisoning in 24 individuals treated by alcohol dehydrogenase competitive inhibitors, cofactors and HD. Two patients required HD formore than 14 days, and two died. In 19 cases, the meanethylene glycol elimination half-life during high-efficiency HD was 165 minutes (95% confidence interval of151-180 minutes). In a training set of 12 patients with acute ethylene glycol poisoning, using the 90th percentile half-life (195 minutes) and a target ethylene glycol concentration of 2 mmol/l (12.4 mg/dl) allowed all cases to reach a safe ethylene glycol under 3 mmol/l (18.6 mg/dl). The prediction model was then validated in a set of seven acute ethylene glycol poisonings. Thus, the HD session time in hours can be estimated using 4.7 x (Ln [the initial ethylene glycol concentration (mmol/l)/2]), provided that metabolic acidosis is corrected.

Chenopodium album Linn. leaves prevent ethylene glycol-induced urolithiasis in rats

Ethnopharmacological relevanceThe leaves of Chenopodium album Linn. are traditionally used for correction of kidney diseases and urinary stones. The present work investigated the effect of methanolic and aqueous extracts of leaves of Chenopodium album on experimentally-induced urolithiasis in rats to substantiate its traditional use as antilithiatic agent. Materials and methodsThe leaf extract was standardized by HPLC. Urolithiasis was induced in rats by administration of 0.75% v/v of ethylene glycol (EG) in distilled water and in addition, vehicle or methanol (CAME) or aqueous (CAAE) extract of the leaves of Chenopodium album each in the dose 100, 200 and 400mg/kg or Cystone (750mg/kg) were administered daily orally for 28 days. Urolithiasis was assessed by estimating the calcium, phosphorus, urea, uric acid, and creatinine in both urine and plasma. The volume, pH and oxalate levels were also estimated in urine. The renal oxalate content was estimated in kidney while calcium oxalate deposits were observed histologically. ResultsThe treatment with CAME or CAAE for 28 days significantly attenuated the EG-induced elevations in the urine and plasma levels of calcium, phosphorus, urea, uric acid and creatinine along with decrease in urine volume, pH and oxalates. The treatments also decreased renal tissue oxalate and deposition of oxalate crystals in kidney due to EG treatment. The effects of CAME and CAAE were comparable to standard antilithiatic agent, cystone. The findings indicate the preventive effect of CAME and CAAE which can be due to inhibitory effect on crystallization and stone dissolution. The effect was attributed to the presence of phytochemicals like flavonoids and saponins. ConclusionIn conclusion, Chenopodium album leaves exhibited antilithiatic effect and validates its ethnomedicinal use in urinary disorders and kidney stones.

Analisa Sifat Fisikokimia Tanin Kulit Akasia Mangium Untuk Bahan Baku Perekat

Tannin is a derivative from organic compound from glycosides found in various plants, the mos t important commercial condensed t annin oblained from gymnosperms species for example Acacia mangium. Tannin is one of the adhesive materials that can have a dimension al stability of wood. Tannin contains flavonoid compounds that have hydroxyl groups that are reactive to condense against other materials as a cross-link agent, like formaldehyde, which may increase the number of polymer units of tannins, thus increasing the bonding strength of tannin based adhesives. Based on the results of physicochemical analysis of extracts (tannins) from the bark of A. mangium as a raw material for adhesives, it can be conc l u d e d that the A. mangium tannin had a higher reactivity toward formaldehyde of 96%, reactivity of t annin toward h examefhylene tetramine of 46.18%, tannins toward ethylene glycol of 3.07% and tannins toward dimeth yl ol urea of 183.59%. Meanwhile, the value of reactive polyphenol content determined by UV-Method showed in tannin with formaldehyde of 97.65%, tannins with hexamethylene tetramine of 46%, tannins with ethylene glycol of 2%, and tannins with dimelhylolurea of 56.26%. The resuits of gelation time (gel t ime) measurements ful l filled the requirements of JIS K 6833- 1980 by the treatment of hexamelhylenen t etramine for variable II and III, and the treatment of ethylene glycol (variable VI). The viscosity values by t he Ireatment of hexamethylenen tetramine (variable II, III, and IV), for ethylene glycol (variable II - VI) met the requirement conditions by JIS K 6833-1980.

Improved Performances of Solid Tantalum Electrolytic Capacitors Using EG-treated PEDOT:PSS Conducting Polymer as Cathode Electrodes

The electrical properties of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films were improved by ethylene glycol (EG). Solid tantalum electrolytic capacitors (STEC) fabricated using such EG-treated PEDOT:PSS films as the cathode electrodes exhibited high performances. The equivalent series resistance (ESR) and capacitance–frequency performance of the STEC were significantly improved comparing to those without EG treatment. Particularly, the leakage current (LC) was lowered at the same time.

Investigating the expanding behavior and thermal stability of HDPy modified organo-bentonite by X-ray diffraction technique

Bentonites are commonly used in scientific investigations and industrial applications due to their superior properties. As they have high cation exchange capacity (CEC), they are widely used as an adsorbent in pollution control. Although their cation adsorption capability is greater, their organic and anionic material adsorption ability is very limited or non-existent. Fortunately, this limitation can be eliminated by intercalation of organic or/and inorganic cations into their structure. Changes due to modification should be identified by characterization techniques in order to figure out realized structural changes. In this study, it is aimed to use X-ray powder diffraction (XRD) technique in order to clarify the expanding behavior and thermal stability of HDPy modified organo-bentonite. For this purpose, organo-bentonite (OBent) was synthesized by intercalation of organic surfactant, hexadecylpyridinium cation (HDPy), into purified bentonite (PBent). Products were characterized by X-ray powder diffraction (XRD) using Cu Kα radiation under various conditions: solvation with water and ethylene glycol (EG) and heat treatments at 100°C, 350°C and 550°C. Existence of mixed-layer clay formation was investigated and PBent and OBent XRD patterns were simulated by NEWMOD software. The PBent sample contains small amounts of mixed layer illite/smectite. Results of XRD analysis supports the notion that HDPy+ is intercalated within interlayer and basal spacing increases from 12.29 to 18.84Å. Degradation of the organic cation is observed, however some residues from intercalate still appears to remain in the structure upon heating up to 550°C. The persistence of these intercalates in OBent over a wide range of temperature holds promise for their use in environmental remediation studies and gaining a better understanding of the mechanisms of interaction with pollutants. Furthermore, this study presents a new perspective in examining the expanding behavior and thermal stability of organo-bentonites and investigating the existence of mixed-layer clay in organo-bentonites by using X-ray powder diffraction (XRD) technique with different treatments.

Effects of Cryoprotectant Agents on Equine Ovarian Biopsy Fragments in Preparation for Cryopreservation

The exposure effect of cryoprotectant agents (CPAs) on morphology of preantral follicles (PAFs), stromal cell and PAF densities, and area of equine ovarian fragments were evaluated. Three independent experiments with identical methodologies were performed. Each experiment was composed of one CPA (dimethyl sulfoxide, ethylene glycol, or propylene glycol) and was performed in three replicates. Ovarian biopsy fragments were harvested from six mares in each experiment and submitted to the cryoprotectants using four times of exposure (0, 10, 15, and 20 minutes). PAF and stromal cell densities, and area of the fragments were not affected (P > .05) by any of the CPAs throughout the time of exposure. However, the morphology of the PAFs was affected (P < .05) by the CPAs. In the propylene glycol and dimethyl sulfoxide, higher (P < .05) percentages of abnormal PAFs were observed at 10 and 20 minutes of exposure, respectively. The PAF morphology in the ethylene glycol treatments was not affected (P > .05) throughout the times of exposure. Positive correlations (r = 0.57–0.77; P < .001, power = 96%–99%) were identified between PAF density and stromal cell density in all experiments. In conclusion, (1) ethylene glycol seems to be a less harmful CPA to equine PAFs, (2) exposure to CPAs did not affect the cell density and area of ovarian fragments, (3) PAF density was positively correlated with stromal cell density, and (4) stromal cell density did not affect the morphology of PAFs.