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171.
Household‐level interview data from a probability sample survey conducted in the northeastern Ecuadorian Amazon in 1990 are used to examine the determinants of income and assets among migrant farmers in the agricultural frontier. Multivariate analysis indicates that size of plot owned, proximity to markets, duration of residence, quality of soil, receipt of technical assistance, off‐farm employment and initial wealth positively influence current household income and wealth. More land in cattle pasture is also associated with higher status. Some settlers are prospering relative to others despite variable soil quality, unsustainable land uses, geographic isolation, apparent scarcity of labor, and lack of supportive infrastructure. The article closes with a discussion of implications for policies to assist small farmers, with some consideration of the potential ecological consequences of farmers’ activities. 相似文献
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173.
Frigi S Pereira F Pereira L Yacoubi B Gusmão L Alves C Khodjet el Khil H Cherni L Amorim A El Gaaied A 《Forensic science international》2006,160(1):80-83
The 17 Y-chromosomal short tandem repeats (STRs) included in the AmpFLSTR Yfiler PCR Amplification Kit (AB Applied Biosystems) (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4) were typed in two Berber communities, a small village (Takrouna) and a town (Sejenane), from North Tunisia. As expected, diversity was higher in the town, even when compared with a pool of three small Berber communities, probably due to the combination of different founder effects and genetic drifts operating in the small villages. 相似文献
174.
Miguel Ruiz-Canela López 《Revista de derecho y genoma humano》2006,(25):199-204
The European Congress on biopolitics entitled "Connecting civil society implementing basic values" was held in March 2006 in Berlin. It was organised by the Heinrich B?ll foundation and the Institut Mensch, Ethik und Wissenschaft. The aim of the Congress was to provide a forum for discussion on the ethical and social aspects derived from biotechnology and genetics on human beings. This work summarises some of the aspects that reveal the international interest and relevance of this meeting. 相似文献
175.
Fernández-Rodríguez A Ballesteros S de Ory F Echevarría JE Alvarez-Lafuente R Vallejo G Gómez J 《Forensic science international》2006,161(1):8-14
Infections are considered to be an important cause of unexpected death in children. It has also been assumed that respiratory viruses are involved in the genesis of sudden infant death syndrome (SIDS). The Spanish National Institute of Toxicology and Forensic Sciences act as the forensic reference centre for Spain. We analyse the experience of this centre in the virological study of 64 cases of sudden children death where viral serology, virological cultures, herpesviruses polymerase chain reaction (PCR) and electron microscopy were performed. According to pathological findings, death could only be attributed to an adenovirus infection in one amygdalitis with upper airways stenosis and asphyxia. Human herpes virus 6 (HHV-6) was detected by PCR in one case with pathological findings characteristic of SIDS. Recent infection by respiratory syncytial virus (RSV), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) were also detected. Meanwhile, 85.9% of the cases yielded negative viral results. Twenty-eight infants were finally categorised as SIDS. Pathological findings of infection were detected in 12 patients despite the negativity of viral analyses. Although viral infection is an uncommon cause of sudden children death, a complete microbiological investigation will help to solve the puzzle of SIDS. Definitive guidelines for microbiological analyses need to be updated whilst new pathogens are discovered or new techniques are implemented in order to clarify unsolved cases. 相似文献
176.
Tenaglia M Scollo A Tripaldi R Grappiolo I Perichón AM 《Forensic science international》2004,141(2-3):185-187
Allele frequencies for nine short tandem repeats (STRs) loci (CSF1PO, TPOX, THO1, F13AO1, FES/FPS, vWA, D16S539, D7S820 and D13S317) and two variable number tandem repeats (VNTRs) were obtained from a sample of 270 unrelated individuals born in the Rosario city, Santa Fe province of Argentina. 相似文献
177.
178.
Sánchez-Diz P Gusmão L Beleza S Benítez-Páez A Castro A García O Solla LP Geada H Martín P Martínez-Jarreta B de Fátima Pinheiro M Raimondi E Silva de la Fuente SM Vide MC Whittle MR Zarrabeitia MT Carracedo A Amorim A;GEP-ISFG 《Forensic science international》2003,135(2):158-162
A collaborative exercise was carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG) in order to evaluate the performance of two Y-chromosome STR PCR tetraplexes, which include the loci DYS461, GATA C4, DYS437 and DYS438 (GEPY I), and DYS460, GATA A10, GATA H4 and DYS439 (GEPY II). The participating laboratories were asked to type three samples for the eight markers, using a specific amplification protocol. In addition, two control samples, with known haplotypes, were provided. The results obtained by the 13 different participating laboratories were identical, except for two laboratories that failed to type correctly the same two samples for GATA C4. By sequence analyses, two different GATA C4 allele structures were found. One control sample (allele 21) and two questioned samples (allele 22, correctly typed by all the laboratories, and allele 25) presented the following repeat structure: (TCTA)4(TGTA)2(TCTA)2(TGTA)2(TCTA)n, but different from the one found for allele 26 in one sample included in this exercise, as well as in the second control sample (allele 23), namely (TCTA)4(TGTA)2(TCTA)2(TGTA)2(TCTA)2(TGTA)2(TCTA)n. The collaborative exercise results proved that both Y-tetraplexes produce good amplification results, with the advantage of being efficiently typed using different separation and detection methodologies. However, since GATA C4 repeat presents a complex structure, with alleles differing in sequence structure, efficient denaturing conditions should be followed in order to avoid typing errors due to sizing problems. 相似文献
179.
Serological and histological examinations of the muscles of the calf of an Egyptian mummy dated between the third and first centuries B.C. were performed. Human protein was identified, the ABO phenotype was determined as type B, and morphological disruption of the cells was observed. 相似文献
180.
Allele frequencies of six short tandem repeat (STR) loci were determined in a Caucasian urban sample of La Plata city and three Amerindian sample populations of Argentina. Allele frequencies showed differences between urbans and Amerindians, and among Amerindians as well. The degree of genetic differentiation of subpopulations was mainly due to the Amerindian contribution. Mapuche, Mocovi, and pooled Amerindian populations showed little evidence of HW disequilibrium, and association of alleles. In the urban sample, there is no evidence of population substructuring. Forensic probabilities of exclusion and matching showed high differences between the population groups. Finally, La Plata sample did not show differences with Caucasians from other geographic regions. 相似文献