8 research outputs found
Functional upgrading in Chinaâs export processing sector
Functional upgrading occurs when a firm acquires more sophisticated functions within an existing value chain. In this paper, we analyze if there is evidence of this type of upgrading in Chinaâs export processing regime by investigating dynamics in the relative prevalence of Import & Assembly (IA) versus Pure Assembly (PA) processing trade over the period 2000-2013. Firms in both regimes provide similar manufacturing services to foreign companies, but IA firms also conduct the sophisticated tasks of quality control, searching, financing and storing imported materials. Consistent with a trend of functional upgrading, we show that the share of IA trade in total processing trade has increased rapidly during the period 2000-2006, both overall and within product categories. Furthermore, we find that this trend has gone hand in hand with improvements in a sectorâs labor productivity and unit values. Against expectations, we find that this process has slowed down notably during the period 2006-2013.status: publishe
Genetic diversity of HLA system in two populations from Durango, Mexico: Durango city and rural Durango
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 479 Mexicans from the state of Durango living in Durango city (NâŻ=âŻ153) and rural communities (NâŻ=âŻ326), to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes found in the state of Durango include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in Durango are European (54.34âŻÂ±âŻ1.68) and Native American (45.66âŻÂ±âŻ2.24), while African genetic component was virtually absent (0.00âŻÂ±âŻ2.03). However, African haplotypes could be estimated at a proportion of 9.13
Genetic diversity of HLA system in three populations from Chihuahua, Mexico: Chihuahua City, Ciudad JuĂĄrez and rural Chihuahua
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 461 Mexicans from the state of Chihuahua living in Chihuahua city (NâŻ=âŻ119), Ciudad JuĂĄrez (NâŻ=âŻ106) and rural communities (NâŻ=âŻ236), to obtain information regarding allelic and haplotypic frequencies and their linkage disequilibrium. We find that the most frequent haplotypes found in the state of Chihuahua include seven Native American and three European haplotypes. Admixture estimates revealed that the main genetic components in Chihuahua are European (52.12âŻÂ±âŻ0.88 by ML; 41.53 of European haplotypes) and Native American (39.51âŻÂ±âŻ2.17 by ML; 37.45 of Native American haplotypes), while African genetic component was less apparent (8.36âŻÂ±âŻ1.47 by ML; 11.70 of African haplotypes)
Genetic diversity of HLA system in two populations from San Luis PotosĂ, Mexico: San Luis PotosĂ City and rural San Luis PotosĂ
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 117 Mexicans from the state of San Luis PotosĂ living in the city of San Luis PotosĂ (NâŻ=âŻ30) and rural communities (NâŻ=âŻ87), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes in the state include 13 Native American, six European, two African and two Asian haplotypes. Admixture estimates revealed that the main genetic components are Native American (52.72âŻÂ±âŻ0.66 by ML; 48.29 of Native American haplotypes) and European (34.62âŻÂ±âŻ4.28 by ML; 32.48 of European haplotypes), and a relatively high African genetic component (12.66âŻÂ±âŻ4.61 by ML; 10.26 of African haplotypes)
Genetic diversity of HLA system in three populations from Coahuila, Mexico: TorreĂłn, Saltillo and rural Coahuila
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 684 Mexicans from the state of Coahuila living in Saltillo (NâŻ=âŻ72), TorreĂłn (NâŻ=âŻ396) and rural communities (NâŻ=âŻ216), to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes found in the state of Coahuila include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Coahuila are European (49.72âŻÂ±âŻ4.18 by ML; 37.49 of European haplotypes) and Native American (45.01âŻÂ±âŻ2.69 by ML; 42.98 of Native American haplotypes), while African genetic component is less apparent (5.27âŻÂ±âŻ1.88 by ML; 9.92 of African haplotypes)
Genetic diversity of HLA system in two populations from Nuevo LeĂłn, Mexico: Monterrey and rural Nuevo LeĂłn
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 665 Mexicans from the state of Nuevo LeĂłn living in the city of Monterrey (NâŻ=âŻ226) and rural communities (NâŻ=âŻ439), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes in the state of Nuevo LeĂłn include 12 Native American and three European haplotypes. Admixture estimates revealed that the main genetic components in the state of Nuevo LeĂłn are Native American (54.53âŻÂ±âŻ0.87 by ML; 48.88 of Native American haplotypes) and European (38.67âŻÂ±âŻ4.06 by ML; 32.59 of European haplotypes), and a less prominent African genetic component (6.80âŻÂ±âŻ4.30 by ML; 8.26 of African haplotypes)
Genetic diversity of HLA system in a population sample from Aguascalientes, Mexico
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 95 Mexicans from the state of Aguascalientes to obtain information regarding allelic and haplotypic frequencies and their linkage disequilibrium. We find that the most frequent haplotypes in the state of Aguascalientes include four Native American, three European and one Asian haplotypes. Admixture estimates revealed that the main genetic components in the state of Aguascalientes are Native American (54.53âŻÂ±âŻ3.22 by ML; 44.21 of Native American haplotypes) and European (44.34âŻÂ±âŻ0.45 by ML; 40.53 of European haplotypes), and a relatively low African genetic component (1.13âŻÂ±âŻ2.33 by ML; 5.26 of African haplotypes)
The immunogenetic diversity of the HLA system in Mexico correlates with underlying population genetic structure
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) allele groups and alleles by PCR-SSP based typing in a total of 15,318 mixed ancestry Mexicans from all the states of the country divided into 78 sample sets, providing information regarding allelic and haplotypic frequencies and their linkage disequilibrium, as well as admixture estimates and genetic substructure. We identified the presence of 4268 unique HLA extended haplotypes across Mexico and find that the ten most frequent (HFÂ >Â 1%) HLA haplotypes with significant linkage disequilibrium (Îââ„0.1) in Mexico (accounting for 20% of the haplotypic diversity of the country) are of primarily Native American ancestry (A*02~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*08~DQB1*04, A*68~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*14~DQB1*03:01, A*24~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*04~DQB1*03:02, A*02~B*40:02~DRB1*04~DQB1*03:02, A*68~B*35~DRB1*04~DQB1*03:02, A*02~B*15:01~DRB1*04~DQB1*03:02). Admixture estimates obtained by a maximum likelihood method using HLA-A/-B/-DRB1 as genetic estimators revealed that the main genetic components in Mexico as a whole are Native American (ranging from 37.8% in the northern part of the country to 81.5% in the southeastern region) and European (ranging from 11.5% in the southeast to 62.6% in northern Mexico). African admixture ranged from 0.0 to 12.7% not following any specific pattern. We were able to detect three major immunogenetic clusters correlating with genetic diversity and differential admixture within Mexico: North, Central and Southeast, which is in accordance with previous reports using genome-wide data. Our findings provide insights into the population immunogenetic substructure of the whole country and add to the knowledge of mixed ancestry Latin American population genetics, important for disease association studies, detection of demographic signatures on population variation and improved allocation of public health resources.1 Introduction 2 Subjects, materials and methods 2.1 Subjects 2.2 HLA typing 2.3 Statistical analysis 2.3.1 HLA allelic and haplotypic diversity 2.3.2 Admixture proportions calculations 2.3.3 Genetic diversity and genetic substructure assessment 3 Results 3.1 HLA allele groups 3.2 Haplotypic diversity 3.3 Admixture estimates 3.4 Genetic diversity and genetic substructure assessment 4 Discussion 4.1 Admixture estimates in Mexican populations and immunogenetic diversity 4.2 The Native American immunogenetic component in Mexican populations 4.3 Implications of the study of alleles and haplotypes of the HLA system in Mexican populations and final considerations 5 Conclusio