'n Onlangse besoek aan die VSA het weer my oe oopgemaak vir die vraag: Is stoettelers en tele... more 'n Onlangse besoek aan die VSA het weer my oe oopgemaak vir die vraag: Is stoettelers en telersverenigings nie besig om in die teenoorgestelde rigting as kommersiele melkboere te beweeg nie?
Revista Internacional De Contaminacion Ambiental, 2009
In May 1998, a large number of forest fires in the region of southern Mexico and Cen tral America... more In May 1998, a large number of forest fires in the region of southern Mexico and Cen tral America, released huge amounts of contaminants that were transported over the Pacific Ocean, then, due to a change in air current direction, the primary contaminants and their secondary pollutant products impacted central New Mexico after 5 to 6 days transport time. The total distance traveled was approximately 3000 km from the fire source. Background measurements of a number of key chemical markers were taken before and during the haze incursion at a site located at Socorro, NM. A number of days before the haze episode in NM, large areas of Texas, Louisiana and the lower Mississippi River valley were also inundated by smoke from the fires. The sum of carbonyl compounds was 5.6 ppbv before and 15.5 ppbv during the smoke event; the sum of carboxylic acids went from 7.2 ppbv to 8.6 ppbv; C1-C2 hydrocarbons went from 270 ppbv to 133 ppbv; particulate NO3 - went from 0.1 to 1.3 μg/m 3 ; SO4 -2 went...
Analysis of the components of biological samples can be extremely challenging due to low concentr... more Analysis of the components of biological samples can be extremely challenging due to low concentrations of the compounds of interest, high concentrations of other compounds and the complexity of samples. In order to obtain quality measures of the concentrations of the analytes of interest, instrument-based methods must show good selectivity, high sensitivity and the ability to calibrate the instrument for the analytes of interest. Sample preparation steps and HPLC separations provide some of the selectivity needed.
CRV Xseed met sy indrukwekkende internasionale bande, beskik oor die vermoe om die beste genetika... more CRV Xseed met sy indrukwekkende internasionale bande, beskik oor die vermoe om die beste genetika te vind en dit teen die mees bekostigbare pryse aan die Suid-Afrikaanse boer beskikbaar te stel. Die jongste toevoeging tot die Holstein-reeks, is die genomika-bul, Bronson, van die VSA.
The words 'it's in the genes' are not only applicable to people with outstanding char... more The words 'it's in the genes' are not only applicable to people with outstanding characteristics - it also applies to bulls that have proven themselves. Research allows us to constantly improve the way in which we study genes, thus enabling us to unravel a bull's potential - will it be an average animal or will it be a number one? An animal's genetic potential is distributed across the DNA in thousands of genes. Genetic markers are small, recognisable pieces of DNA located close to the genes. They have more or less the same heritability as genes. A marker offers information on the genes and the animal's genetic potential. Should the markers of a young bull be mapped, the effect of these markers can be added up, thus offering information on the animal's genetic potential. This extra information allows for a much higher reliability of the predicted index (based on parent average). The selection of animals on the basis of marker information, is known as mark...
CRV Xseed with its international contacts, has the ability to source the best genetics and make t... more CRV Xseed with its international contacts, has the ability to source the best genetics and make them available at affordable prices for the South African farmer. The latest addition to the Holstein line-up is the genomic bull, Bronson, from the USA.
In May 1998, a large number of forest fires in the region of southern Mexico and Central America,... more In May 1998, a large number of forest fires in the region of southern Mexico and Central America, released huge amounts of contaminants that were transported over the Pacific Ocean, then, due to a change in air current direction, the primary contaminants and their secondary pollutant products impacted central New Mexico after 5 to 6 days transport time. The total distance traveled was approximately 3000 km from the fire source. Background measurements of a number of key chemical markers were taken before and during the haze incursion at a site located at Socorro, NM. A number of days before the haze episode in NM, large areas of Texas, Louisiana and the lower Mississippi River valley were also inundated by smoke from the fires. The sum of carbonyl compounds was 5.6 ppbv before and 15.5 ppbv during the smoke event; the sum of carboxylic acids went from 7.2 ppbv to 8.6 ppbv; C1-C2 hydrocarbons went from 270 ppbv to 133 ppbv; particulate NO 3 - went from 0.1 to 1.3 μg/m 3 ; SO 4 -2 wen...
Many producers of purebred and commercial beef cattle can profitably utilise artificial inseminat... more Many producers of purebred and commercial beef cattle can profitably utilise artificial insemination (AI). The benefit of AI is to use the best genetics at affordable prices. This is very beneficial for young stud breeders.
Atmospheric concentrations of aldehydes, ketones, carboxylic acids, hydrocarbons, PAN, PPN, O{sub... more Atmospheric concentrations of aldehydes, ketones, carboxylic acids, hydrocarbons, PAN, PPN, O{sub 3}, NO{sub x} and CO have been determined simultaneously for diurnal periods from two to four weeks duration over several winter and summer seasons from 1993-1995 in Albuquerque, New Mexico (an urban site) and Socorro, New Mexico (a rural site). Both sites are located in similar geographical and meteorological settings and are subjected to temperature inversions that can create typical {open_quotes}brown cloud{close_quotes} conditions in Albuquerque. Oxygenated fuel, with ethanol as the primary oxygenate, is mandated in Albuquerque in the winter and concerns have been expressed that a side effect of such fuel use may be the increased production of aldehydes. Total aldehyde concentrations are greater in Albuquerque than in Socorro both summer and winter with a greater difference in the winter suggesting that in the summertime, biogenic emission, greater dispersion and photochemistry play...
Objective: There are no safety or absorption studies to guide topical timolol therapy for treatme... more Objective: There are no safety or absorption studies to guide topical timolol therapy for treatment of chronic wounds. This study was undertaken to address this gap. Approach: A prospective, observational, cross-sectional comparative study of timolol plasma levels in patients after topical administration to a chronic wound, compared with levels in patients after timolol ocular administration for the indication of glaucoma. Results: There was no statistically significant difference in the average plasma level of timolol in wound as compared with glaucoma patients. No bradycardia or wheezing was observed after administration. Innovation: We determined the single time point concentration of timolol in plasma 1 h after application of timolol 0.5% gel-forming solution to debrided chronic wounds, providing insight as to the safety of this emerging off-label treatment. Conclusion: The topical application of timolol for chronic wounds shares the same safety profile as the widely used application of ocular administration for glaucoma.
A novel UPLC-UV method was developed for analysis of timolol in human plasma using a simple, fast... more A novel UPLC-UV method was developed for analysis of timolol in human plasma using a simple, fast, and cost effective ion-exchange SPE procedure, followed by separation on a C18 UPLC column with a mobile phase consisting of acetonitrile, phosphate buffer, and sodium 1-octane sulfonate as an ion pairing agent. The method was fully validated according to US-FDA guidelines, and was found to be sufficiently accurate and precise for analysis of timolol in human plasma for clinical pharmacokinetic studies. The application of ion-exchange SPE cartridges for purification of timolol in plasma produced excellent percent recoveries and good sample clean-up, while the ion-pairing separation described here allowed quantitation of timolol without interference from endogenous sample components. The method lower limit of detection was 1.7 ng/mL and the lower limit of quantitation was 5.0 ng/mL, allowing for analysis of therapeutic concentrations of timolol in plasma.
Journal of ocular pharmacology and therapeutics : the official journal of the Association for Ocular Pharmacology and Therapeutics, 2017
To evaluate the systemic pharmacokinetics (PKs) of travoprost 0.004% preserved with Polyquad(®) (... more To evaluate the systemic pharmacokinetics (PKs) of travoprost 0.004% preserved with Polyquad(®) (TRAVATAN(®)) in pediatric patients with glaucoma or ocular hypertension. This was a phase 1, open-label, multicenter clinical study of patients aged ≥2 months to <18 years. Patients received daily administration of travoprost 0.004% preserved with Polyquad in both eyes for 7 days. Plasma samples were collected 30 min before the final dose and at 10, 20, 40, and 80 min postdose. The main outcome measure was maximum concentration of travoprost free acid in plasma (Cmax). Included in the PK analysis were 24 patients (average age 9.6 ± 4.9 years). At least 1 sample with quantifiable levels of travoprost free acid was collected for 11 patients. The mean Cmax was 0.0471 ± 0.0105 ng/mL for patients aged 2 months to <3 years; 0.0258 ± 0.0128 ng/mL for ages 3 to <12 years; and 0.0109 ± 0.0005 ng/mL for ages 12 to <18 years. Travoprost was undetectable in samples collected predose from...
Milcom 1982 Ieee Military Communications Conference Progress in Spread Spectrum Communications, Oct 1, 1982
Directsequencemodulatedspreadspectrum tems arequitesimilarinmanywaysto more conventional digital ... more Directsequencemodulatedspreadspectrum tems arequitesimilarinmanywaysto more conventional digital communications systems. employsomeformofphaseshiftamplitude sb frequency shiftkeyingtomodulatetheircar andprovidethedesiredspreadbandwidth.A consideration, however, is thechoiceof car modulation toprovidemaximumantijamming ma whileoperating innonlinear processing, plu imizingimpactonsynchronization andcost/c plexityof themodulators, demodulators, and chronizers required. Thispaperexaminestherelationships that existbetweenthevariouscandidate waveforn showstheircommonroots. Alsodefinedare criteriathataffectthechoiceof a wavefor wherevariousimplementations arepossible.
During tours to Europe, clients of CRV Xseed have always been impressed by the quality of silage ... more During tours to Europe, clients of CRV Xseed have always been impressed by the quality of silage produced. Many dairy management advisors from Europe have even jokingly stated that the Dutch farmers make silage and South African farmers make compost.
'n Onlangse besoek aan die VSA het weer my oe oopgemaak vir die vraag: Is stoettelers en tele... more 'n Onlangse besoek aan die VSA het weer my oe oopgemaak vir die vraag: Is stoettelers en telersverenigings nie besig om in die teenoorgestelde rigting as kommersiele melkboere te beweeg nie?
Revista Internacional De Contaminacion Ambiental, 2009
In May 1998, a large number of forest fires in the region of southern Mexico and Cen tral America... more In May 1998, a large number of forest fires in the region of southern Mexico and Cen tral America, released huge amounts of contaminants that were transported over the Pacific Ocean, then, due to a change in air current direction, the primary contaminants and their secondary pollutant products impacted central New Mexico after 5 to 6 days transport time. The total distance traveled was approximately 3000 km from the fire source. Background measurements of a number of key chemical markers were taken before and during the haze incursion at a site located at Socorro, NM. A number of days before the haze episode in NM, large areas of Texas, Louisiana and the lower Mississippi River valley were also inundated by smoke from the fires. The sum of carbonyl compounds was 5.6 ppbv before and 15.5 ppbv during the smoke event; the sum of carboxylic acids went from 7.2 ppbv to 8.6 ppbv; C1-C2 hydrocarbons went from 270 ppbv to 133 ppbv; particulate NO3 - went from 0.1 to 1.3 μg/m 3 ; SO4 -2 went...
Analysis of the components of biological samples can be extremely challenging due to low concentr... more Analysis of the components of biological samples can be extremely challenging due to low concentrations of the compounds of interest, high concentrations of other compounds and the complexity of samples. In order to obtain quality measures of the concentrations of the analytes of interest, instrument-based methods must show good selectivity, high sensitivity and the ability to calibrate the instrument for the analytes of interest. Sample preparation steps and HPLC separations provide some of the selectivity needed.
CRV Xseed met sy indrukwekkende internasionale bande, beskik oor die vermoe om die beste genetika... more CRV Xseed met sy indrukwekkende internasionale bande, beskik oor die vermoe om die beste genetika te vind en dit teen die mees bekostigbare pryse aan die Suid-Afrikaanse boer beskikbaar te stel. Die jongste toevoeging tot die Holstein-reeks, is die genomika-bul, Bronson, van die VSA.
The words 'it's in the genes' are not only applicable to people with outstanding char... more The words 'it's in the genes' are not only applicable to people with outstanding characteristics - it also applies to bulls that have proven themselves. Research allows us to constantly improve the way in which we study genes, thus enabling us to unravel a bull's potential - will it be an average animal or will it be a number one? An animal's genetic potential is distributed across the DNA in thousands of genes. Genetic markers are small, recognisable pieces of DNA located close to the genes. They have more or less the same heritability as genes. A marker offers information on the genes and the animal's genetic potential. Should the markers of a young bull be mapped, the effect of these markers can be added up, thus offering information on the animal's genetic potential. This extra information allows for a much higher reliability of the predicted index (based on parent average). The selection of animals on the basis of marker information, is known as mark...
CRV Xseed with its international contacts, has the ability to source the best genetics and make t... more CRV Xseed with its international contacts, has the ability to source the best genetics and make them available at affordable prices for the South African farmer. The latest addition to the Holstein line-up is the genomic bull, Bronson, from the USA.
In May 1998, a large number of forest fires in the region of southern Mexico and Central America,... more In May 1998, a large number of forest fires in the region of southern Mexico and Central America, released huge amounts of contaminants that were transported over the Pacific Ocean, then, due to a change in air current direction, the primary contaminants and their secondary pollutant products impacted central New Mexico after 5 to 6 days transport time. The total distance traveled was approximately 3000 km from the fire source. Background measurements of a number of key chemical markers were taken before and during the haze incursion at a site located at Socorro, NM. A number of days before the haze episode in NM, large areas of Texas, Louisiana and the lower Mississippi River valley were also inundated by smoke from the fires. The sum of carbonyl compounds was 5.6 ppbv before and 15.5 ppbv during the smoke event; the sum of carboxylic acids went from 7.2 ppbv to 8.6 ppbv; C1-C2 hydrocarbons went from 270 ppbv to 133 ppbv; particulate NO 3 - went from 0.1 to 1.3 μg/m 3 ; SO 4 -2 wen...
Many producers of purebred and commercial beef cattle can profitably utilise artificial inseminat... more Many producers of purebred and commercial beef cattle can profitably utilise artificial insemination (AI). The benefit of AI is to use the best genetics at affordable prices. This is very beneficial for young stud breeders.
Atmospheric concentrations of aldehydes, ketones, carboxylic acids, hydrocarbons, PAN, PPN, O{sub... more Atmospheric concentrations of aldehydes, ketones, carboxylic acids, hydrocarbons, PAN, PPN, O{sub 3}, NO{sub x} and CO have been determined simultaneously for diurnal periods from two to four weeks duration over several winter and summer seasons from 1993-1995 in Albuquerque, New Mexico (an urban site) and Socorro, New Mexico (a rural site). Both sites are located in similar geographical and meteorological settings and are subjected to temperature inversions that can create typical {open_quotes}brown cloud{close_quotes} conditions in Albuquerque. Oxygenated fuel, with ethanol as the primary oxygenate, is mandated in Albuquerque in the winter and concerns have been expressed that a side effect of such fuel use may be the increased production of aldehydes. Total aldehyde concentrations are greater in Albuquerque than in Socorro both summer and winter with a greater difference in the winter suggesting that in the summertime, biogenic emission, greater dispersion and photochemistry play...
Objective: There are no safety or absorption studies to guide topical timolol therapy for treatme... more Objective: There are no safety or absorption studies to guide topical timolol therapy for treatment of chronic wounds. This study was undertaken to address this gap. Approach: A prospective, observational, cross-sectional comparative study of timolol plasma levels in patients after topical administration to a chronic wound, compared with levels in patients after timolol ocular administration for the indication of glaucoma. Results: There was no statistically significant difference in the average plasma level of timolol in wound as compared with glaucoma patients. No bradycardia or wheezing was observed after administration. Innovation: We determined the single time point concentration of timolol in plasma 1 h after application of timolol 0.5% gel-forming solution to debrided chronic wounds, providing insight as to the safety of this emerging off-label treatment. Conclusion: The topical application of timolol for chronic wounds shares the same safety profile as the widely used application of ocular administration for glaucoma.
A novel UPLC-UV method was developed for analysis of timolol in human plasma using a simple, fast... more A novel UPLC-UV method was developed for analysis of timolol in human plasma using a simple, fast, and cost effective ion-exchange SPE procedure, followed by separation on a C18 UPLC column with a mobile phase consisting of acetonitrile, phosphate buffer, and sodium 1-octane sulfonate as an ion pairing agent. The method was fully validated according to US-FDA guidelines, and was found to be sufficiently accurate and precise for analysis of timolol in human plasma for clinical pharmacokinetic studies. The application of ion-exchange SPE cartridges for purification of timolol in plasma produced excellent percent recoveries and good sample clean-up, while the ion-pairing separation described here allowed quantitation of timolol without interference from endogenous sample components. The method lower limit of detection was 1.7 ng/mL and the lower limit of quantitation was 5.0 ng/mL, allowing for analysis of therapeutic concentrations of timolol in plasma.
Journal of ocular pharmacology and therapeutics : the official journal of the Association for Ocular Pharmacology and Therapeutics, 2017
To evaluate the systemic pharmacokinetics (PKs) of travoprost 0.004% preserved with Polyquad(®) (... more To evaluate the systemic pharmacokinetics (PKs) of travoprost 0.004% preserved with Polyquad(®) (TRAVATAN(®)) in pediatric patients with glaucoma or ocular hypertension. This was a phase 1, open-label, multicenter clinical study of patients aged ≥2 months to <18 years. Patients received daily administration of travoprost 0.004% preserved with Polyquad in both eyes for 7 days. Plasma samples were collected 30 min before the final dose and at 10, 20, 40, and 80 min postdose. The main outcome measure was maximum concentration of travoprost free acid in plasma (Cmax). Included in the PK analysis were 24 patients (average age 9.6 ± 4.9 years). At least 1 sample with quantifiable levels of travoprost free acid was collected for 11 patients. The mean Cmax was 0.0471 ± 0.0105 ng/mL for patients aged 2 months to <3 years; 0.0258 ± 0.0128 ng/mL for ages 3 to <12 years; and 0.0109 ± 0.0005 ng/mL for ages 12 to <18 years. Travoprost was undetectable in samples collected predose from...
Milcom 1982 Ieee Military Communications Conference Progress in Spread Spectrum Communications, Oct 1, 1982
Directsequencemodulatedspreadspectrum tems arequitesimilarinmanywaysto more conventional digital ... more Directsequencemodulatedspreadspectrum tems arequitesimilarinmanywaysto more conventional digital communications systems. employsomeformofphaseshiftamplitude sb frequency shiftkeyingtomodulatetheircar andprovidethedesiredspreadbandwidth.A consideration, however, is thechoiceof car modulation toprovidemaximumantijamming ma whileoperating innonlinear processing, plu imizingimpactonsynchronization andcost/c plexityof themodulators, demodulators, and chronizers required. Thispaperexaminestherelationships that existbetweenthevariouscandidate waveforn showstheircommonroots. Alsodefinedare criteriathataffectthechoiceof a wavefor wherevariousimplementations arepossible.
During tours to Europe, clients of CRV Xseed have always been impressed by the quality of silage ... more During tours to Europe, clients of CRV Xseed have always been impressed by the quality of silage produced. Many dairy management advisors from Europe have even jokingly stated that the Dutch farmers make silage and South African farmers make compost.
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