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Ultra pure water production by a small local water treatment plant suitable for high quality urea solution AUS 32 defined by DIN 700070
No full textAbstract: A small local water treatment plant for high quality urea solution AUS 32 defined by DIN 700070 is created. The technological parameters of this plant are researched during the ultra pure water production used as a solvent for urea solution AUS 32. A very salty under-ground water was treated to get a deionized ultra pure water with specific electric conduc-tivity χ ≤ 1 μS/cm. It was used as a solvent during the automotive grade urea solution (AUS 32) production. The product obtained was according to quality requirements of DIN 70007. The role and use of deionized ultra pure water addressed to quality assurance guidance document (QAGD) is discussed
No full textThe professional socialization of social workers involves the process of acquiring knowledge and skills, values, attitudes, and professional identit
The Effect of Forging on Microstructure and Mechanical Properties of In Situ TiC/Ti Composite
Get PDFIn this paper, 1 vol% TiC/Ti-1100 composite was prepared, and the transus temperature of the composite was measured using metallographic techniques. The composite was forged at 1173, 1333 and 1423 K, respectively. Microstructure of forged samples was studied by optical microscopy (OM) and transmission electron microscopy (TEM). The forging in the upper phase field was investigated especially. Mechanical properties of the composite after hot forging were tested by tensile tests at ambient temperature. It was found that there is an about 100 K increase in transus temperature compared to monolithic Ti-1100 alloy. Widmanstatten microstructure, bimodal microstructure and microstructure containing aligned plate were obtained after forging at various temperatures. Compared to Widmanstatten microstructure or bimodal microstructure, there is an increase about 200 MPa in ultimate tensile strength for the microstructure containing aligned plate. The increase in tensile strength for the microstructure containing aligned plate may result from two factors: one is the work hardening during the forging process, and the other is the interaction between = interface and dislocations in phase during tensile process
Conceptual Framework for Speech Language Pathologists to Work with Migrants: A Focus on Malta
Get PDFAbstract The goal of this paper is to describe the current state, needs and values of migrants with a focus on relevant global issues and Malta as a case study. It also aims to review services offered to these migrants, identify aspects that require attention and draw up a framework that could be applied to enhance services to the culturally diverse populations, particularly speech therapy. The health care services offered to migrants are reviewed in the light of attitudes and expectations. Professional perceptions and competences to work with these populations are also discussed and perceptions of migrants about services offered to them are taken into consideration. Issues related to equitable professional practice and the training of health care professionals to address needs of the cultural diverse community are discussed. Strategies to implement the conceptual framework are suggested
PLASMA PHARMACOKINETICS AND TISSUE DISTRIBUTION OF A N-PYRROLO- [1,2-C]IMIDAZOLYLPHENYL SULFONAMIDE IN RATS
Get PDFThis paper is available online at http://dmd.aspetjournals.org ABSTRACT: TY029, an N-pyrrolo[1,2-c]imidazolylphenyl sulfonamide herbicide, controls economically important weeds through inhibition of protoporphyrinogen oxygenase. As partial satisfaction of regulatory requirements to establish safety and to aid in the interpretation of toxicology bioassays, a rat metabolism study of TY029 was performed to define the pharmacokinetics and tissue distribution of this compound. Animals were exposed to single 50-and 2-mg/kg doses of [hydantoin-5-14 C]TY029 by oral gavage. The tissue distribution studies revealed that generally greater than 5% of the oral dose was found in the carcass, gastrointestinal tract, liver, and the whole blood when plasma microgram equivalents per gram of TY029 was at maximum or at half of the maximum. However, these concentrations rapidly declined to negligible levels. By 96 h after the oral administration of [hydantoin-5-14 C]TY029, the highest value reported for any one of the collected tissues was below 0.5% of administered dose. Therefore, neither TY029 nor its metabolites was sequestered in tissues to appreciable levels. The C max , C max/2 , and area under the curve (AUC INF ) obtained from the plasma pharmacokinetics suggested that in general single-dosed female rats absorbed and eliminated the test compounds faster than their male counterparts. Mass spectral evaluations of the plasma from single high-and low-dose male and female rats identified the plasma constituents related to the test compound. Although the parent molecule was present in all plasma samples, the three acidic metabolites were the predominant plasma metabolites in the high-dose groups. The overall plasma profile included TY029 and six metabolites. TY029 1 Materials and Methods Test Substance. TY029 and its metabolites were synthesized by DuPont Crop Protection Products (Wilmington, DE). Radiolabeled TY029 was synthesized at New England Nuclear and supplied as a white powder. The test substance was stable under the conditions of this study as determined by a lack of change in color and physical state or HPLC purity profile of standards. The chemical purity of the test material was Ͼ99%, whereas its radiochemical and chiral purity was determined to be Ͼ97%. Animals. Male and nulliparous female Crl:CD(SD)IGS BR rats were obtained from Charles River Laboratories (Raleigh, NC). This rat strain was chosen because it is also the strain used in safety evaluation studies of TY029. At the time of dosing, rats were 7 to 12 weeks of age. All animals weighed 173 to 264 g. Upon arrival, rats were maintained under quarantine for at least 6 days. Animals purchased cannulated were quarantined for at least 2 days. Animal rooms were targeted at a temperature of 23 Ϯ 1°C and a relative humidity of 50 Ϯ 10%. Animal rooms were artificially illuminated (fluorescent light) on a 12-h light/dark cycle. Standard chunk (Certified Rodent LabDiet 5002; PMI Nutrition International, Inc., Richmond, IN) or pelletized rodent chow (Rodent Pellet Certified Formula A/1 Chow; P.J. Noyes Company, Inc., Lancaster, NH) and tap water were provided ad libitum, except during the fasting periods prior to dosing. Chunk chow was given to rats during the quarantine period, and pelletized food or chunk chow was given to rats that were on study. Dose Concentration and Preparation. Oral dosing was chosen as the route of administration because that is the primary route of human exposure and is required by U.S. Environmental Protection Agency Federal Insecticide, Fungi-1 Abbreviations used are: TY029, an N-pyrrolo [1,2-c]imidazolylphenyl sulfonamide herbicide; amu, atomic mass units; AUC, area under the curve; C max , maximal plasma concentration; C max/2 , half-maximal plasma concentration; equiv, equivalent; HPLC, high-performance liquid chromatography; LOD, limit of detection; LSC, liquid scintillation counting; MS, mass spectrometry; PK, pharmacokinetics; SPE, solid phase extraction; tC max , time required to reach maximal plasma concentration; tC max/2 , time required to reach half-maximal plasma concentration; GI, gastrointestinal. Address correspondence to: Dr. Mehran F. Moghaddam, Pfizer Global Research and Development, Eastern Point Rd., MS4098, Groton, CT 06340-9988. E-mail: [email protected] 0090-9556/02/3001-47-54$3.00 DRUG METABOLISM AND DISPOSITION Vol. 30 DMD 30:47-54, 2002 Printed in U.S.A. , No. 1 Copyright © 2002 by The American Society for Pharmacology and Experimental Therapeutics 437/953758 47 cide, and Rodenticide Act and European Union Commission Directives Guidelines. Dosing solutions were prepared in silanized glassware by dissolving the test substance in reagent grade water containing 0.5% methyl cellulose and vortexing until completely dissolved (J. C. Maslanka, personal communications). This solution was used for oral dosing via gavage. Unlabeled TY029 was mixed with [hydantoin-5-14 C]TY029 to achieve the appropriate concentration needed for dosing. Samples of the dosing solutions were analyzed to confirm the purity, concentration, and specific activity. All dose preparation data were recorded on Debra software (version 5.1a; LabLogic, Sheffield, England). Debra instructions on aliquot preparation were followed during dose preparation, analysis of 14 C concentrations, and radiochemical purity. While stored frozen at Ϫ20°C, dosing solutions were considered usable for up to 2 weeks. Freezer storage stability conducted on 172-day-old samples indicated an absence of degradation at Ϫ20°C. The total dose volume was targeted at ϳ4 ml/kg. In the low-dose group, rats received a nominal single oral dose of 2 mg/kg of body weight by gavage. About 30 Ci of radioactivity was delivered to each rat. The low dose was chosen to be nontoxic, but expected to be high enough to allow for metabolite identification in excreta and samples containing Ͼ5% of dose. In the high-dose group, rats received a nominal single oral dose of 50 mg/kg of body weight by gavage. Again, about 30 Ci of radioactivity was delivered to each rat. The high dose was selected to approximate the minimal effects observed on the hematopoietic system and nutritional parameters in the rat developmental and subchronic toxicity studies. Metabolite profiling and identification were undertaken at both dose levels using unlabeled TY029. Animal Dosing and Sample Collection. All dosing solutions were analyzed for chemical and radiochemical purity before dosing as described above. Plasma pharmacokinetics of total radioactivity. Groups of six male and six female rats were purchased with cannula surgically implanted in the jugular vein. All rats were fasted overnight (15-20 h). Half of the male and half of the female rats received a single 2 mg/kg nominal dose of [hydantoin-5-14 C]TY029 via oral gavage. The second group of rats received a single 50 mg/kg nominal dose of [hydantoin-5-14 C]TY029 via oral gavage. Rats were housed individually in glass metabolism units. Blood samples were collected as described below at approximately 15 and 30 min, 1, 1.5, 2, 4, 6, 8, 12, and 24 h, and every 24 h thereafter for a total of 168 h (7 days). Plasma samples were prepared as described below and stored at approximately Ϫ20°C until needed. Plasma pharmacokinetics of nonradiolabeled TY029 and metabolites. For the purpose of plasma metabolite profiling and pharmacokinetics of individual compounds, a group of six male and six female rats were purchased with MOGHADDAM ET AL. cannula surgically implanted in the jugular vein. These animals were treated in the same manner as described for those in the total radioactivity pharmacokinetics study except that they were dosed with nonradiolabeled TY029. Blood samples were collected at 15 and 30 min, 1, 2, 4, and 8 h after administration of the oral dose. Plasma samples were prepared as described below and stored at approximately Ϫ20°C until preparation for LC/MS analysis. Blood collection. Blood (approximately 0.2-0.4 ml) was drawn from the cannula and placed into heparinized tubes for analysis of total radioactivity in plasma and red blood cells. Tail vein blood was collected in instances when the jugular cannula failed to supply blood. Rats were placed into a polyethylene restrainer on a heating pad to increase blood circulation in the extremities before collecting blood from the tail vein. A maximum of 1 ml/100 g of body weight was withdrawn in a 24-h period. An additional 0.5% blood volume based on body weight was withdrawn thereafter, not to exceed a total of 2% of the animal's body weight, as mandated by DuPont Animal Welfare Committee. In addition, animals were given blood transfusions, if needed. The blood transfusion solution was prepared as described in the literature Tissue distribution at tC max and tC max/2 . Groups of 16 male and 16 female rats were placed in glass metabolism units and fasted overnight. Eight animals from each group were gavaged with a nominal dose of 2 mg/kg and the other eight from each sex group were gavaged with a nominal dose of 50 mg/kg of [hydantoin-5-14 C]TY029. At the time of maximal blood 14 C concentrations (tC max ), determined for each dose in the total radioactivity pharmacokinetics study (above), four rats from each group were sacrificed by CO 2 asphyxiation. At the time when the blood concentration of 14 C fell to one-half of C max (tC max/2 ), all of the remaining animals were sacrificed. In all cases, whole blood (plasma and red blood cells), liver, kidney, heart, lung, thyroid, spleen, brain, fat, carcass, testes, ovaries, pituitary, muscle, adrenals, skin, bone (marrow and mineral), GI tract and contents, uterus, and pancreas were collected. All tissues were frozen at approximately Ϫ20°C until processing and analysis. Terminal plasma and tissue distributions. A group of eight male and eight female rats were dosed with 2 or 50 mg/kg of [hydantoin-5-14 C]TY029 via oral gavage after fasting overnight. After 96 h (Ͼ90% excretion), rats were terminated and tissues described in the previous section were collected. These samples were stored frozen at approximately Ϫ20°C. Sample Preparation. The tissue and plasma samples were processed prior to radioactivity counting and metabolite profiling. Tissues. Solid samples were combusted in sample oxidizers (models 306 and 307; Packard, Meriden, CT) for 1 to 1.5 min while trapping the liberated radioactive CO 2 and volatiles in CarboSorb E (Packard). Radioactivity was then assayed by liquid scintillation counting (Packard). Plasma. To separate plasma from red blood cells, blood was centrifuged at approximately 4°C for 15 min and 2000g. Plasma was stored at approximately Ϫ20°C. Radioactivity in plasma was quantified by LSC. For LC/MS analysis, a 96-well SPE method (X. Tang, personal communications) was used to extract the compounds of interest from spiked and actual rat plasma samples. In brief, the high-performance extraction disk plate [Octadecyl (C 18 ) SD and 1200 l of polypropylene microtubes in microracks (3M Filtration Products, St. Paul, MN)], placed in a QIAvac manifold system (QIAGEN, Inc., Valencia, CA), was conditioned and washed with 200 l of acetonitrile and then 250 l of 1% formic acid in water. Depending on the level of radioactivity in each plasma sample, 50 to 150 l of plasma was mixed with 250 l of 1% aqueous formic acid in the SPE well and eluted under vacuum. After the wells were washed three times with 200 l of 1% formic acid, the analytes were eluted with 4 ϫ 100 l of acetonitrile. The eluents were dried under nitrogen gas before PHARMACOKINETICS AND TISSUE DISTRIBUTION OF A HERBICIDE reconstitution in the appropriate amount of 9:1, water/acetonitrile (with 0.4% formic acid). All reconstituted solutions were transferred to autosampler microvials for LC/MS/MS analysis. Measurement of Radioactivity. Radioactivity was measured using a Packard Tri-CarbLiquid Scintillation Analyzer (model 2500TR series). Samples were counted by LSC for 10 min. Group data were represented as mean Ϯ S.D. Samples with Ͼ10% LSC variability were reanalyzed when possible. HPLC Method. The primary HPLC method employed a Hewlett-Packard Series 1100 pump (Palo Alto, CA) equipped with a diode array detector and an autosampler. The HPLC method used a Zorbax Rx-C 8 , 2.1 ϫ 150-mm column with 5-m-diameter packing, and a Zorbax analytical guard column, 4.6 ϫ 12.5-mm with 5-m-diameter packing (MAC Mod, Chadds Ford, PA) attached in tandem and maintained at 40°C. The flow rate was 0.3 ml/min with a gradient of 9:1, 0.1% aqueous formic acid/acetonitrile to 100% acetonitrile in 40 min. The injection volume was 40 to 50 l. Mass Spectrometer Operating Conditions. The LC/MS analysis was carried out in the electrospray negative ion mode with the ion trap LC/MS LCQ (Finnigan, San Jose, CA) system. The electrospray voltage, detector voltage, and capillary temperature were 4.45 V, 900 V, and 230°C, respectively. Mass spectrometry tune files, at optimized conditions, were generated for TY029 and the acidic metabolite 3 Preparation of standard and fortified plasma solutions. A 1000-ppm stock solution of each standard was prepared by weighing 1 mg of standard on an analytical balance and dissolving with 1 ml of acetonitrile. These solutions were stored in the freezer until use. Standard mixes were prepared by taking the appropriate amount of each stock solution and diluting with the appropriate amount of HPLC grade H 2 O. These solutions were prepared fresh at the beginning of each set of analyses. To produce the fortified samples, 360 l of control plasma was spiked with 40 l of a 5-ppm standard mixture and then extracted as described above in the sample preparation section. This fortification level represented 500 ppb in plasma. As a control, unspiked rat plasma was extracted using the same extraction method. The control sample extract was analyzed using the same LC/MS method to determine whether there was any interference in the selected monitored ion for each analyte at its specific retention time. The level of TY029 and metabolites delivered by the standard solution to generate calibration curves ranged from 0.5 to 60 ng depending on the animal dose group and the dilution factor used for the extracted samples. The method was validated by analyzing a control unfortified plasma extract and a set of fortified plasma samples at 500 ppb with the LC/MS method. Detector response. The mass spectrum for TY029 and its diastereomeric metabolite The m/z value and relative abundance of those ions were used to confirm the identity of the target compounds and increase the method selectivity. Limit of detection (LOD). The LOD for TY029 and the five target metabolites were set at the level which yielded an LC/MS selective ion signal with a signal to noise ratio of 5:1. Statistical and pharmacokinetics calculations. Data were collected and compiled in Debra software (version 5.1a). Data manipulations and statistical calculations (mean Ϯ S.D.) were performed in Excel software (Microsoft, Redmond, WA). Samples with Ͼ10% LSC variability were reanalyzed when possible. For pharmacokinetics calculations, Origin (version 4.1; Microcal Software, Inc., Northampton, MA) and WinNonlin (version 3.2, Pharsight Corp., Mountainview, CA) softwares were used. Results Plasma Pharmacokinetics of Total Radioactivity. The objective of this experiment was to determine C max , C max/2 , tC max , tC max/2 , terminal half-life (t 1/2 lambda Z), and AUC INF after a single oral dose of radiolabeled TY029. Plasma Pharmacokinetics of TY029 and Metabolites. The objective of this study was to identify and quantitate individual TY029-related compounds in plasma. Therefore, plasma samples from male and female rats dosed with high and low levels of nonradiolabeled TY029 were analyzed by LC/MS. Each compound (or mixture of isomers) was identified based on its retention time comparison to the synthetic standards and diagnostic LC/MS fragments. Representative plasma LC/MS traces of TY029 and its metabolites for high-dose rats are shown i
THE EFFECT OF POTENTIAL ABSORPTIVE CAPACITY AND INNOVATION ON COMPETITIVE ADVANTAGE: A MODEL FROM PARTICIPATIVE LEADERSHIP PERSPECTIVE
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Developmental History of Landscape Painting In Modern Nigerian Art: The Lagos State Example
Get PDFAbstract Nature and the built environment present diverse themes and contexts for artistic expression, and these have been the concern of artists throughout the ages, especially painters. This paper therefore examines the implantation of landscape painting as an artistic genre and a visual document of socio-economic and urban development in Nigeria, using as the basis Lagos (the orb of Nigeria's artistic practice and art marketing). Through literature, interviews and purposively selected works, the paper discusses some historical, political and socio-economic factors responsible for the growth of landscape painting in Lagos, Nigeria. The art of landscape painting in Lagos State, as revealed by the paper, dates back to the 1920s in Nigeria; and while the works of pioneer landscape painters focused on naturalistic realism, their contemporary counterparts explore diverse stylesand thematic foci in their works. The paper concludes that the developmental history of landscape painting in Nigeria cannot be conclusive, until efforts are made by art scholars to capture its implantation and growth in other major cities/towns in the country
Capturing Renewable Resource Dynamics in Top-Down Energy Models: A Hybrid Method Applied to Offshore Wind in China
Get PDFAbstract Top-down modeling approaches are often criticized based on limited ability to represent detailed technological information. We extend a hybrid method for representing heterogeneity in the quality of resource inputs when modeling energy production, focusing on China's offshore wind electricity as an example. Using a stylized top-down economic model, we compare the supply curve derived from policy simulations in our general equilibrium approach to a static supply curve and show that predictions of electricity supplied differ systematically. We further show how the hybrid model predicts a "wind rush" phenomenon as a carbon price applied across the economy rises, the piecewise shape of the supply curve dictates that large quantities of wind capacity will be deployed upon reaching threshold electricity prices. This effect is typically not captured by traditional top-down models, which typically rely on smooth curve fits for resource representation. Finally, we show how to introduce a piecewise supply curve based on observed wind resource data into a top-down economic model that includes many heterogeneous resource prices and multiple sectors. The results suggest that planning and policy measures are necessary to coordinate the pace of renewables deployment with infrastructure and grid network expansion to avoid congestion and curtailment