Lina ahmad - Academia.edu (original) (raw)

Papers by Lina ahmad

Polymer Degradation and Stability, 2006

Investigations of the pyrolysis of poly(vinyl chloride) (PVC) in the presence of copper metal (Cu... more Investigations of the pyrolysis of poly(vinyl chloride) (PVC) in the presence of copper metal (Cu), copper(II) oxide (CuO) and copper(II) chloride (CuCl 2 ) are of potential importance because of the likelihood of the formation of these copper compounds during the thermal degradation of PVC-coated copper wires, a step in the recovery of copper from waste. The presence of Cu, CuO and CuCl 2 (i) retards the thermal degradation of PVC in air and in nitrogen and (ii) decreases the percentages of volatile products produced at both stages of the decomposition. These effects are greatest for PVCeCuO. The presence of copper, CuO or CuCl 2 in PVC has a major effect on the nature of the gaseous emissions of the thermal decomposition in air and in nitrogen. The concentrations of total chlorine, aliphatic hydrocarbons, aromatic hydrocarbons, chlorinated hydrocarbons and soot particulates are all affected relative to an equivalent amount of PVC. These changes are greatest for the PVCeCuO system for which total chlorine emissions in air and nitrogen are reduced by 40% in air and 20% in nitrogen, benzene emissions are reduced by greater than 90% in air and nitrogen, other aromatic and chloroaromatic emissions are reduced, and soot particulate emissions are reduced by more than 50% as the concentrations of aliphatic compounds are increased. These changes are consistent with the presence of copper or its compounds permitting more efficient combustion of the carbon content of the PVC and particularly in the case of PVCeCuO with the removal of chlorine during pyrolysis in the inorganic phase.

Nature Genetics, 2010

Smoking is a leading global cause of disease and mortality 1 . We established the Oxford-GlaxoSmi... more Smoking is a leading global cause of disease and mortality 1 . We established the Oxford-GlaxoSmithKline study (Ox-GSK) to perform a genome-wide meta-analysis of SNP association with smoking-related behavioral traits. Our final data set included 41,150 individuals drawn from 20 disease, population and control cohorts. Our analysis confirmed an effect on smoking quantity at a locus on 15q25 (P = 9.45 × 10 −19 ) that includes CHRNA5, CHRNA3 and CHRNB4, three genes encoding neuronal nicotinic acetylcholine receptor subunits. We used data from the 1000 Genomes project to investigate the region using imputation, which allowed for analysis of virtually all common SNPs in the region and offered a fivefold increase in marker density over HapMap2 (ref. 2) as an imputation reference panel. Our fine-mapping approach identified a SNP showing the highest significance, rs55853698, located within the promoter region of CHRNA5. Conditional analysis also identified a secondary locus (rs6495308) in CHRNA3.

Tetrahedron, 1995

Improved routes to the quinoxalinone acid chloride 1 and the 3-methylquinoxalinone 21 are describ... more Improved routes to the quinoxalinone acid chloride 1 and the 3-methylquinoxalinone 21 are described. These intermediates are used to obtain the fluoroionophores 15-19 and 27-29, respectively. The effects of the complexation of metal ions by the fluoroionophores is discussed. A red pigment 26 is obtained from 21.

Parasitology Research, 2010

Distomum musculorum suis (DMS), the mesocercarial stage of the trematode Alaria alata, can cause ... more Distomum musculorum suis (DMS), the mesocercarial stage of the trematode Alaria alata, can cause severe damages within their hosts, and since several reports about cases of human larval alariosis have been published, it became apparent that infected game animals and in particular wild boars are a potential source of infection for both humans and animals. A final statement concerning the health risks for consumers could not be given due to the lack of information about both the prevalence of DMS and the suitability of Trichinella inspection methods to detect this parasite in wild boar meat. Our studies concentrate on (1) the verification of suitability of the official digestion methods for Trichinella spp. for DMS detection in wild boars, (2) development, optimization, and validation of methods, and (3) the distribution of the parasites within their paratenic hosts. A total of 868 individual samples/digests from 48 wild boars were analyzed by the reference method for Trichinella detection in meat samples according to regulation (EC) No. 2075/2005. In addition to the official protocol, a method modification with Pankreatin© and bile acid was applied for analysis of adipose tissue samples (n = 89). On the basis of our results, a new detection method based on a larvae migration technique was developed and used for detection of DMS in 574 single samples. Furthermore, the distribution patterns of DMS in wild boars in a total of 1377 single sample migrations/digestions from 35 positive animals were analyzed by application of all three methods. The official digestion method for Trichinella spp. in wild boars meat is inapplicable for the detection of A. alata mesocercariae as it shows shortcomings in both digestion and sampling. A direct comparison between the newly developed A. alata mesocercariae migration technique and the official digestion method for Trichinella spp. based on 574 single samples from 18 animals clearly shows that the sensitivity to detect A. alata developmental stages in tissues of wild boars of the new method is nearly 60% higher compared with the magnetic stirrer method for pooled sample digestion as laid down in regulation (EC) No. 2075/2005. Among other advantages, this method offers a simple, highly applicable, fast, and cost effective way to detect DMS in wild boars which is already applicable in routine veterinary inspection.

Polymer Degradation and Stability, 2006

Investigations of the pyrolysis of poly(vinyl chloride) (PVC) in the presence of copper metal (Cu... more Investigations of the pyrolysis of poly(vinyl chloride) (PVC) in the presence of copper metal (Cu), copper(II) oxide (CuO) and copper(II) chloride (CuCl 2 ) are of potential importance because of the likelihood of the formation of these copper compounds during the thermal degradation of PVC-coated copper wires, a step in the recovery of copper from waste. The presence of Cu, CuO and CuCl 2 (i) retards the thermal degradation of PVC in air and in nitrogen and (ii) decreases the percentages of volatile products produced at both stages of the decomposition. These effects are greatest for PVCeCuO. The presence of copper, CuO or CuCl 2 in PVC has a major effect on the nature of the gaseous emissions of the thermal decomposition in air and in nitrogen. The concentrations of total chlorine, aliphatic hydrocarbons, aromatic hydrocarbons, chlorinated hydrocarbons and soot particulates are all affected relative to an equivalent amount of PVC. These changes are greatest for the PVCeCuO system for which total chlorine emissions in air and nitrogen are reduced by 40% in air and 20% in nitrogen, benzene emissions are reduced by greater than 90% in air and nitrogen, other aromatic and chloroaromatic emissions are reduced, and soot particulate emissions are reduced by more than 50% as the concentrations of aliphatic compounds are increased. These changes are consistent with the presence of copper or its compounds permitting more efficient combustion of the carbon content of the PVC and particularly in the case of PVCeCuO with the removal of chlorine during pyrolysis in the inorganic phase.

Nature Genetics, 2010

Smoking is a leading global cause of disease and mortality 1 . We established the Oxford-GlaxoSmi... more Smoking is a leading global cause of disease and mortality 1 . We established the Oxford-GlaxoSmithKline study (Ox-GSK) to perform a genome-wide meta-analysis of SNP association with smoking-related behavioral traits. Our final data set included 41,150 individuals drawn from 20 disease, population and control cohorts. Our analysis confirmed an effect on smoking quantity at a locus on 15q25 (P = 9.45 × 10 −19 ) that includes CHRNA5, CHRNA3 and CHRNB4, three genes encoding neuronal nicotinic acetylcholine receptor subunits. We used data from the 1000 Genomes project to investigate the region using imputation, which allowed for analysis of virtually all common SNPs in the region and offered a fivefold increase in marker density over HapMap2 (ref. 2) as an imputation reference panel. Our fine-mapping approach identified a SNP showing the highest significance, rs55853698, located within the promoter region of CHRNA5. Conditional analysis also identified a secondary locus (rs6495308) in CHRNA3.

Tetrahedron, 1995

Improved routes to the quinoxalinone acid chloride 1 and the 3-methylquinoxalinone 21 are describ... more Improved routes to the quinoxalinone acid chloride 1 and the 3-methylquinoxalinone 21 are described. These intermediates are used to obtain the fluoroionophores 15-19 and 27-29, respectively. The effects of the complexation of metal ions by the fluoroionophores is discussed. A red pigment 26 is obtained from 21.

Parasitology Research, 2010

Distomum musculorum suis (DMS), the mesocercarial stage of the trematode Alaria alata, can cause ... more Distomum musculorum suis (DMS), the mesocercarial stage of the trematode Alaria alata, can cause severe damages within their hosts, and since several reports about cases of human larval alariosis have been published, it became apparent that infected game animals and in particular wild boars are a potential source of infection for both humans and animals. A final statement concerning the health risks for consumers could not be given due to the lack of information about both the prevalence of DMS and the suitability of Trichinella inspection methods to detect this parasite in wild boar meat. Our studies concentrate on (1) the verification of suitability of the official digestion methods for Trichinella spp. for DMS detection in wild boars, (2) development, optimization, and validation of methods, and (3) the distribution of the parasites within their paratenic hosts. A total of 868 individual samples/digests from 48 wild boars were analyzed by the reference method for Trichinella detection in meat samples according to regulation (EC) No. 2075/2005. In addition to the official protocol, a method modification with Pankreatin© and bile acid was applied for analysis of adipose tissue samples (n = 89). On the basis of our results, a new detection method based on a larvae migration technique was developed and used for detection of DMS in 574 single samples. Furthermore, the distribution patterns of DMS in wild boars in a total of 1377 single sample migrations/digestions from 35 positive animals were analyzed by application of all three methods. The official digestion method for Trichinella spp. in wild boars meat is inapplicable for the detection of A. alata mesocercariae as it shows shortcomings in both digestion and sampling. A direct comparison between the newly developed A. alata mesocercariae migration technique and the official digestion method for Trichinella spp. based on 574 single samples from 18 animals clearly shows that the sensitivity to detect A. alata developmental stages in tissues of wild boars of the new method is nearly 60% higher compared with the magnetic stirrer method for pooled sample digestion as laid down in regulation (EC) No. 2075/2005. Among other advantages, this method offers a simple, highly applicable, fast, and cost effective way to detect DMS in wild boars which is already applicable in routine veterinary inspection.