The Chilean subduction zone is one of the most seismically active regions globally,characterized by extensive intermediatedepth seismicity in the slab.In this study,we construct a new earthquake catalog for northern C...The Chilean subduction zone is one of the most seismically active regions globally,characterized by extensive intermediatedepth seismicity in the slab.In this study,we construct a new earthquake catalog for northern Chile using seismic waveforms assembled for the period of 2014-2019,from which 320,070 P-wave and 232,907 S-wave first arrivals are obtained for 25,763 earthquakes.Grid search location method NonLinLoc is applied to determine initial earthquake locations and double-difference location method is used to improve relative event locations.The distribution of earthquakes exhibits distinct patterns to the north and south of 21°S.There are many more earthquakes deeper than~150 km to the south of 21°S,while relatively fewer to the north.The intraslab earthquakes shallower than~80 km generally reveal a distinct double seismic zone,and the gap between the two seismic planes disappears at a depth of approximately~80 km,followed by a concentration of seismicity in the depth range of~80-150 km.In the deeper slab,there exist several seismicity clusters with distinct earthquake activities down to~300 km.These characteristics shown in slab seismicity are likely caused by different mechanisms and can be helpful for understanding the subduction process.展开更多
Chile,a pioneer and benchmark partner for China's free trade.cooperation in Latin America,holds a special position in China-Latin America economic and trade relations.It was the first Latin American country to sig...Chile,a pioneer and benchmark partner for China's free trade.cooperation in Latin America,holds a special position in China-Latin America economic and trade relations.It was the first Latin American country to sign a bilateral free trade agreement with China and the first to reach an upgraded protocol.Chile also established mutual recognition of Authorized Economic Operators(AEO)with China,the first country in South America to do so.展开更多
The Ms ≥ 8.0 strong earthquakes occurring in Chile since 1800 were analyzed using the ternary, quaternary, and quinary commensurability methods and the butterfly structure diagram, and it was believed that the earthq...The Ms ≥ 8.0 strong earthquakes occurring in Chile since 1800 were analyzed using the ternary, quaternary, and quinary commensurability methods and the butterfly structure diagram, and it was believed that the earthquake signal in Chile in 2014 is relatively strong, a large earthquake is likely to occur in Chile in 2014. An analysis of spatial epicenter migrations showed that the longitudinal and latitudinal epicenter migra- tions have symmetry and synchronism, and there were five obvious northward migrations and four southward migrations. The symmetry axis of the longitudinal migrations is at about 71.7°W and that of the latitudinal mi- grations is at about 30°S; these spatial symmetry axes are located at the subduction zone on the western margin of South America, where two major plates (the Nazca Plate and the South American Plate) converge.展开更多
A study of deep penetrating geochemistry--the surface exploration techniques for finding concealed mineral deposits--was carried out over the Spence porphyry copper deposit in Chile by Australian, Canadian and Chinese...A study of deep penetrating geochemistry--the surface exploration techniques for finding concealed mineral deposits--was carried out over the Spence porphyry copper deposit in Chile by Australian, Canadian and Chinese laboratories using selective weak leach methods and is briefly reviewed here. Erratic and weak copper anomalies were obtained above the Spence deposit, which is concealed below a thick piedmont gravel cover. In the literature, such patterns are common in most of the weak selective leach studies carried out over known buried deposits. During exploration in unknown area, such weak leach techniques lead to some success and many dry holes. In this paper, stronger selective leaching methods are developed for oxides and sulfides, which may be the stable end products transformed and accumulated by a mobile precursor phase carried upward through the overburden by gas or water through long spans of geological time. The data obtained by the methods developed in this paper produced more significant and consistent anomalous data than previous efforts. Consequently, the leach approaches described here may increase the effectiveness of deep penetrating geochemistry in exploration for con- cealed ore deposits.展开更多
AIM:To analyze the association of three IL28B single nucleotide polymorphisms with response to therapy in Chilean patients infected with hepatitis C virus CV.METHODS:We studied two groups of patients with chronic CV i...AIM:To analyze the association of three IL28B single nucleotide polymorphisms with response to therapy in Chilean patients infected with hepatitis C virus CV.METHODS:We studied two groups of patients with chronic CV infection genotype 1,under standard combined treatment with pegylated interferon plus ribavirin.One group consisted of 50 patients with sustained virological response,whereas the second group consisted of 49 null responders.In order to analyze the IL28B single nucleotide polymorphisms rs12979860,rs12980275 and rs8099917,samples were used for polymerase chain reaction amplification,and the genotyping was performed by restriction fragment lengthpolymorphism.RESULTS:The IL28B rs12979860 CC,rs12980275 AA and rs8099917 TT genotypes were much more frequently found in patients with sustained virological response compared to null responders 38%,44% and 50% vs 2%,8.2% and 8.2%,respectively.These differences were highly significant in all three cases(P < 0.0001.CONCLUSION:The three IL28B polymorphisms studied are strongly associated with sustained virological response to therapy in Chilean patients with chronic CV genotype 1.展开更多
AIM: To examine the presence of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) specimens collected from Colombia and Chile located in the northern and southern ends of the continent, resp...AIM: To examine the presence of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) specimens collected from Colombia and Chile located in the northern and southern ends of the continent, respectively.METHODS: We examined 47 and 26 formalin-fixed and paraffin-embedded ESCC specimens from Colombia and Chile, respectively. HPV was detected using GP5+/GP6+ primer pair for PCR, and confirmed by Southern blot analysis. Sequencing analysis of L1 region fragment was used to identify HPV genotype. In addition, P16^INK4A protein immunostaining of all the specimens was conducted.RESULTS: HPV was detected in 21 ESCC specimens (29%). Sequencing analysis of L1 region fragment identified HPV-16 genome in 6 Colombian cases (13%) and in 5 Chilean cases (19%). HPV-18 was detected in i0 cases (21%) in Colombia but not in any Chilean case. Since Chilean ESCC cases had a higher prevalence of HPV-16 (without statistical significance), but a significantly lower prevalence of HPV-18 than in Colombian cases (P = 0.011) even though the two countries have similar ESCC incidence rates, the frequency of HPV-related ESCC may not be strongly affected by risk factors affecting the incidence of ESCC. HPV-16 genome was more frequently detected in p16 positive carcinomas, although the difference was not statistically significant. HPV-18 detection rate did not show any association with p16 expression. Well-differentiated tumors tended to have either HPV-16 or HPV-18 but the association was not statistically significant. HPV genotypes other than HPV-16 or 18 were not detected in either country.CONCLUSION: HPV-16 and HPV-18 genotypes can be found in ESCC specimens collected from two South American countries. Further studies on the relationship between HPV-16 presence and p16 expression in ESCC would aid understanding of the mechanism underlying the presence of HPV in ESCC.展开更多
The tempo-spatial variation of seismic activity before great Chile Mw8.8 earthquake on February 27, 2010 is studied. Some results are as follows: ①Two types of seismic gaps appeared before the Chile MwS.8 shock. One...The tempo-spatial variation of seismic activity before great Chile Mw8.8 earthquake on February 27, 2010 is studied. Some results are as follows: ①Two types of seismic gaps appeared before the Chile MwS.8 shock. One is background gap of Mw≥8.0 earthquakes with 360 km length since 1900, the other is seismogenic gap formed by M≥5.5 earth- quakes with 780km length five years before the Chile earthquake; ②There was only one Mw7.1 earthquake in the middle and southern part of Chile from 1986 to 2010. The obvious quiescence of Mw≥7.0 earthquake is the long-term background anomaly for the Chile earthquake; ③ The quiescence of M≥6.5 earthquakes appeared in South American block and its vicinity during the period from 2007 to 2009, and the quietude state has been disappeared three months before the Chile Mw8.8 earthquake; ④ The deep and intermediate-depth earthquake activity has been noticeablely strengthened in the subduction zone of South American block since 1993; ⑤The great Chile earthquake shows that global seismicity is still in the active period of Mw≥8.5 earthquakes since 2004. Based on the characteristics of the former two active periods, several great earthquakes with Mw≥8.5 would take place in a few years. In addition, the circum-Pacific seismic belt would be the main region for Mw≥8.0 earthquakes.展开更多
We applied solution-based ICP-MS method to quantify the trace-elemental signatures in statoliths of jumbo flying squid, Dosidius gigas, which were collected from the waters off northern and central Chile during the sc...We applied solution-based ICP-MS method to quantify the trace-elemental signatures in statoliths of jumbo flying squid, Dosidius gigas, which were collected from the waters off northern and central Chile during the scientific surveys carried out by Chinese squid jigging vessels in 2007 and 2008. The age and spawning date of the squid were back-calculated based on daily increments in statoliths. Eight elemental ratios(Sr/Ca, Ba/Ca, Mg/Ca, Mn/Ca, Na/Ca, Fe/Ca, Cu/Ca and Zn/Ca) were analyzed. It was found that Sr is the second most abundant element next to Ca, followed by Na, Fe, Mg, Zn, Cu, Ba and Mn. There was no significant relationship between element/Ca and sea surface temperature(SST) and sea surface salinity(SSS), although weak negative or positive tendency was found. MANOVA analysis showed that multivariate elemental signatures did not differ among the cohorts spawned in spring, autumn and winter, and no significant difference was found between the northern and central sampling locations. Classification results showed that all individuals of each spawned cohorts were correctly classified. This study demonstrates that the elemental signatures in D. gigas statoliths are potentially a useful tool to improve our understanding of its population structure and habitat environment.展开更多
AIM: To demographically and clinically characterize inflammatory bowel disease (IBD) from the local registry and update data previously published by our group.METHODS: A descriptive study of a cohort based on a regist...AIM: To demographically and clinically characterize inflammatory bowel disease (IBD) from the local registry and update data previously published by our group.METHODS: A descriptive study of a cohort based on a registry of patients aged 15 years or older who were diagnosed with IBD and attended the IBD program at Clínica Las Condes in Santiago, Chile. The registry was created in April 2012 and includes patients registered up to October 2015. The information was anonymously downloaded in a monthly report, and the information on patients with more than one visit was updated. The registry includes demographic, clinical and disease characteristics, including the Montreal Classification, medical treatment, surgeries and hospitalizations for crisis. Data regarding infection with Clostridium difficile (C. difficile) were incorporated in the registry in 2014. Data for patients who received consultations as second opinions and continued treatment at this institution were also analyzed.RESULTS: The study included 716 patients with IBD: 508 patients (71%) were diagnosed with ulcerative colitis (UC), 196 patients (27%) were diagnosed with Crohn’s disease (CD) and 12 patients (2%) were diagnosed with unclassifiable IBD. The UC/CD ratio was 2.6/1. The median age was 36 years (range 16-88), and 58% of the patients were female, with a median age at diagnosis of 29 years (range 5-76). In the past 15 years, a sustained increase in the number of patients diagnosed with IBD was observed, where 87% of the patients were diagnosed between the years 2001 and 2015. In the cohort examined in the present study, extensive colitis (50%) and colonic involvement (44%) predominated in the patients with UC and CD, respectively. In CD patients, non-stricturing/non-penetrating behavior was more frequent (80%), and perianal disease was observed in 28% of the patients. There were significant differences in treatment between UC and CD, with a higher use of corticosteroids, and immunosuppressive and biological therapies was observed in the patients with CD (P < 0.05 and P < 0.01). Significant surgical differences were also observed: 5% of the UC patients underwent surgery, whereas 38% of the CD patients required at least one surgery (P < 0.01). The patients with CD were hospitalized more often during their disease course than the patients with UC (55% and 35% of the patients, respectively; P < 0.01). C. difficile infection was acquired by 5% of the patients in each group at some point during the disease course. Nearly half of the patients consulted at the institution for a second opinion, and 32% of these individuals continued treatment at the institution.CONCLUSION: IBD has continued to increase in the study cohort, slowly approaching the level reported in developed countries.展开更多
Background: Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio?economic, cultural and environmental characteristics. However, green are...Background: Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio?economic, cultural and environmental characteristics. However, green areas, including original fragments, can help to conserve native diversity, improving the functioning of these artificial systems in the long term. Urban areas can still provide habitats usable by wild birds, however the structural charac?teristics of the habitat formed by different types of green area differ, and therefore dissimilar bird diversities are to be expected. The object of this study was to characterise the α and β diversities of birds in different green areas and to analyse how diversity relates to ten variables that characterise the habitat.Methods: We studied the green areas in the city of Temuco, southern Chile(Park, Square and Median strips of main streets), evaluating the variables:(a) surface area,(b) vegetation,(c) estimated human impact as the proportions of vegetation and bare soil by area, and the vehicle traffic. The bird assemblage structures were characterised by α(intra?environment) diversity and β diversity(between environments) and the statistical analysis identified the environmen?tal variables related with the presence and abundance of birds. A statistical model was constructed to describe the contribution of the variables to bird diversity.Results: We found significant differences between the diversity of bird species in the three types of green area. The β showed medium to high similarity between the different study units. There was a negative correlation with bare soil areas; the correlations with vehicle flow, plant structure and tree and shrub cover were not significant, meaning that these variables did not explain the variation in the richness of bird species between the green areas. However the surface area did explain this variation presenting a positive potential relation. There was also a high correlation with the origin(native) of shrub species.Conclusions: The bird diversity varied significantly according to the type of urban green area. The environmental variables presenting significant correlations with bird diversity were: surface area, native species of shrub stratum, shrub cover, and bare soil area. The best multiple regression model showed that the three most important variables for bird diversity are the surface area of the green area, the cover of the shrub stratum and the presence of native shrub species.展开更多
This pilot study documented the occurrence and levels of brominated flame retardants in the tissues of farmed and wild salmon in southern Chile.Samples of Coho salmon and rainbow trout were obtained from fish farms,ri...This pilot study documented the occurrence and levels of brominated flame retardants in the tissues of farmed and wild salmon in southern Chile.Samples of Coho salmon and rainbow trout were obtained from fish farms,rivers and lakes in the Patagonia in Aysen Region,Chile.The samples were analyzed by Gas Chromatography Negative Chemical Ionization Mass Spectrometry for the different polybrominated diphenyl ether(PBDE) congeners.Contaminants were observed in all the samples,and the congeners BDE 17,28,47 and 66 were observed in all both farmed and wild samples.The concentrations were higher in the farmed Coho salmon,presenting significant differences with wild salmon.The levels reached 182 pg/g wet weight(ww) vs.120 ww.In the case of the rainbow trout,the concentrations were lower,although the congener profile was quite similar.The levels reached an average of 100 pg/g ww in the farmed fish versus 110 pg/g ww in wild fish,and no significant difference was observed between the species.In both species,the congener with the highest concentration was BDE 47.Based on this information,the BDE ?ow was estimated for commerce,which is a form of pollutant transport not usually considered in POP pollution studies.A preliminary estimation indicated that the quantity of PBDEs mobilized by commerce was in the order of kg,and in the case of Chile might reach almost 1 kg.展开更多
Based on a qualitative research restricted to aging processes in Chile, the paper presents the experience and significance of dependence in elderly men and how it is related with the social construction of old age. It...Based on a qualitative research restricted to aging processes in Chile, the paper presents the experience and significance of dependence in elderly men and how it is related with the social construction of old age. It is important to know how the identity of aging is configured when facing such a significant biographical and social landmark as the loss of functionality in later life. When analyzing the social construction of dependence in elderly men, three aspects of that configuration stand out: first, the way in which they understand and signify their situations of illness, physical problems, disability, and evaluation of their health;second, the characteristics of the social significant contexts in which disability or physical problems become evident;and third, the actions, roles or activities that they perform in those contexts, which are valued differently according to the experiences of dependence or autonomy. Dependence in elderly men does not appear as a static condition, but rather as a passage from physical-biological conditioners to the social context in which their everyday actions take place. So the agency of the dependence, its construction, experience and significance is the understanding of the social phenomenon of old age.展开更多
Traditional Chinese medicine(TCM) arrived from China to Latin America and the Caribbean in the 1840s due to the massive migration of Chinese people to the region. In a few years, the press noticed the presence of Chin...Traditional Chinese medicine(TCM) arrived from China to Latin America and the Caribbean in the 1840s due to the massive migration of Chinese people to the region. In a few years, the press noticed the presence of Chinese herbalists practicing in different cities and countries regardless of the demographic weight of the Chinese community. The fascination with Chinese doctors implicated not only the press but also the literature, a phenomenon particularly observed in Cuba. In the first decades of the 20th century, the reactivation of Chinese immigration to the region fostered an anti-Chinese climate that materialized in more significant migratory restrictions and control of their businesses, such as what happened with Chinese herbalists. These herbalists who practiced inside and outside the Chinese community started to object to criticism and persecution by the conservative press and professional doctors. Despite this, Chinese doctors will continue to maintain their support of a significant number of ill persons. This work seeks to illuminate the historical relevance of TCM in Latin America and the Caribbean, focusing on the cases of Peru, Chile, and Cuba. This last country was far from China culturally and geographically, but as in many other small towns in the region, Chinese medicine presented an alternative to the treatment of illnesses.展开更多
Great differences in hazard and losses were shown from two tsunamis, both generated in Chile, one in 1960 and the other in 2010. Numerical simulation was applied to the tsunami analysis. The fault dislocation of the s...Great differences in hazard and losses were shown from two tsunamis, both generated in Chile, one in 1960 and the other in 2010. Numerical simulation was applied to the tsunami analysis. The fault dislocation of the seafioor was assumed to equal to the initial tsunami wave field, which can be calculated by the formula of fault dislocation in the elastic isotropic half-space. The linear long wave theory was used as the tsunami hydrodynamic model, and the finite difference method and leap-frog scheme were selected for solving the equations. The accuracy of the simulated results was verified by the observed data in five tide gauges. By means of two scenario tsunamis, the analytical results show that the earthquake magnitude, bathymetry in rupture zone and rapid release of warning information in 2010 tsunami are the main explanations of the aforementioned great difference.展开更多
Aging and widowhood signal a real and symbolic landmark of change toward new vital experiences of elderly people. In the aging experience of women, there are three social age markers that participate directly in the c...Aging and widowhood signal a real and symbolic landmark of change toward new vital experiences of elderly people. In the aging experience of women, there are three social age markers that participate directly in the construction of their identity as women during old age: menopause, work and widowhood. The present paper reports the results of a research on widowhood in old age and the experience of aging in elderly women in Chile. Through a qualitative methodological strategy, in depth biographic interviews were held with elderly people who were widowed after reaching 60 years of age, centering the analysis on its meanings on the body, health and death in old age, highlighting sociocultural aspects of the aging and widowing processes. Approaching widowhood in old age shows us not only a person who has lost a husband, but also what it means to be an elderly woman in a life experience continuum that also brings about key changes to understand the aging process of people, because marital relations can get to be determining factors for the construction of the identity of women and their experience of the aging process.展开更多
We assessed the effects of plantations of exotic trees (Pinus radiata, Eucalyptus globulus, and Populus nigra) on plant biodiversity in the temperate zone of the biodiversity hotspot of Central Chile. This region has ...We assessed the effects of plantations of exotic trees (Pinus radiata, Eucalyptus globulus, and Populus nigra) on plant biodiversity in the temperate zone of the biodiversity hotspot of Central Chile. This region has suffered from intense deforestation in favor of plantation establishment in the major part of the coastal area since the neoliberal turn in 1973. The approach presented aimed to analyze plant biodiversity on the α-, β- and γ-scale. Furthermore, a plantation evaluation index was applied in order to provide quantitative figures on management practices. Species richness is reduced by 50% below plantations. Diversity and evenness index values are also significantly reduced. Analyses on β-similarity indicate that plantations do not host species absent in adjacent native forests, and no additional habitat heterogeneity is gained. On the γ-scale, plantations lower the number of total species observed;especially of endemic species. The abundance of species considered as invasive is significantly higher and frequently, invasive plants dominate the understory. The evaluation index attests rather poor plantation management in Central Chile since plantations are grown as monocultures, natural elements and native species are lacking at specific sites and plantations are insufficiently connected to native plant formations at the landscape scale. Results give much concern since deforestation processes as observed in our study area is about to begin in Patagonia as well. If management practices from the temperate zone are adopted in Patagonia, a considerable decline in plant biodiversity has to be expected there.展开更多
Background: Adolescent obesity is associated with high cardiovascular and metabolic risk. Western diet and reduced physical activity are strong environmental determinants. The “Health Production” model posits that i...Background: Adolescent obesity is associated with high cardiovascular and metabolic risk. Western diet and reduced physical activity are strong environmental determinants. The “Health Production” model posits that individuals born with a certain amount of health stock, which depreciates over life, but can be augmented by individual behaviors, including exercise and dieting. Objective: To study the association between health production and obesity in a random sample of 1692 Chilean adolescents (14.8 ± 0.7 years old), and to study the effect of gender and socioeconomic characteristics on health production. Method: We used an indicator that considered the quality of food intake and physical activity, establishing three categories: good (GHP), intermediate (IHP) and poor health producers (PHP). Multivariate analysis was used to study the odds of obesity and good health production. Results: There was 31% of GHP, 32% of IHP and 38% of PHP. Obesity (Adj. OR: 1.59;95%CI: 1.04 - 2.42) and abdominal obesity (Adj. OR: 2.24;95%CI: 1.35 - 3.40) were significantly higher in the PHP group, compared to the GHP and IHP group. Health production was significantly associated with socioeconomic factors and gender. Female sex and coming from a less wealthy household significantly reduced the odds of good health production. Conclusions: Poor health production in adolescence, as defined by food intake and physical activity, depreciates individuals’ “health stock”, increasing the risk of obesity. In our sample, health production was strongly associated with socio-economic factors and gender.展开更多
This study analyze the relation between body composition, physical activity (PA), and sex in Chilean children from rural and urban public educational institutions. The prevalence of obesity (according to BMI) was ...This study analyze the relation between body composition, physical activity (PA), and sex in Chilean children from rural and urban public educational institutions. The prevalence of obesity (according to BMI) was 30.88% in urban children and 28.93% in rural children. Central obesity presented mainly in the rural girls. Approximately 90% of the participants reported 〈7 h of PA/week, regardless of residential area. In addition, central fat was strongly associated with rural residence; the children reported lower PA levels, and they presented a higher prevalence of central fat. The results reflect the need to implement programs to improve PA conditions in the child urban-rural population.展开更多
We undertook a boat expedition to explore the geological framework of a very remote,lesser-known island,in the Chilean Patagonia:the Diego de Almagro Island(latitude S51°330').This uninhabited,ca.400 km^2 Isl...We undertook a boat expedition to explore the geological framework of a very remote,lesser-known island,in the Chilean Patagonia:the Diego de Almagro Island(latitude S51°330').This uninhabited,ca.400 km^2 Island is one of the very rare exposures of the Mesozoic accretionary subduction complex along the Chilean margin.Unstable weather,strong winds,steep topography,and very dense vegetation make an on-land mission difficult.Careful preparation based on high-resolution satellite images is advised to optimize shore access and minimize risks of injury.Despite a relatively important degree of regional reequilibration of metamorphic assemblages due to sluggish exhumation through the forearc crust,our results have shown that the island is composed of a nappe stack of ocean-floor derived slivers of metasedimentary units that exhibit very different pressure-temperature-time paths during burial by subduction under the Chilean margin and subsequent exhumation.These rocks are witness to a complex thermal evolution of the subduction zone between Jurassic and Cretaceous times from granulite facies to blueschist facies conditions as well as multiple episodes of accretion at ca.35-40 km in depth for almost100 Ma over the Mesozoic era.展开更多
基金supported by National Natural Science Foundation of China(No.41861134009)the PIA ANID(AFB180004)the ANID(PCI PII-180003).
文摘The Chilean subduction zone is one of the most seismically active regions globally,characterized by extensive intermediatedepth seismicity in the slab.In this study,we construct a new earthquake catalog for northern Chile using seismic waveforms assembled for the period of 2014-2019,from which 320,070 P-wave and 232,907 S-wave first arrivals are obtained for 25,763 earthquakes.Grid search location method NonLinLoc is applied to determine initial earthquake locations and double-difference location method is used to improve relative event locations.The distribution of earthquakes exhibits distinct patterns to the north and south of 21°S.There are many more earthquakes deeper than~150 km to the south of 21°S,while relatively fewer to the north.The intraslab earthquakes shallower than~80 km generally reveal a distinct double seismic zone,and the gap between the two seismic planes disappears at a depth of approximately~80 km,followed by a concentration of seismicity in the depth range of~80-150 km.In the deeper slab,there exist several seismicity clusters with distinct earthquake activities down to~300 km.These characteristics shown in slab seismicity are likely caused by different mechanisms and can be helpful for understanding the subduction process.
文摘Chile,a pioneer and benchmark partner for China's free trade.cooperation in Latin America,holds a special position in China-Latin America economic and trade relations.It was the first Latin American country to sign a bilateral free trade agreement with China and the first to reach an upgraded protocol.Chile also established mutual recognition of Authorized Economic Operators(AEO)with China,the first country in South America to do so.
基金supported by the National Natural Science Foundation of China(41171090)the Graduate Student Innovation Foundation of Shaanxi Normal University
文摘The Ms ≥ 8.0 strong earthquakes occurring in Chile since 1800 were analyzed using the ternary, quaternary, and quinary commensurability methods and the butterfly structure diagram, and it was believed that the earthquake signal in Chile in 2014 is relatively strong, a large earthquake is likely to occur in Chile in 2014. An analysis of spatial epicenter migrations showed that the longitudinal and latitudinal epicenter migra- tions have symmetry and synchronism, and there were five obvious northward migrations and four southward migrations. The symmetry axis of the longitudinal migrations is at about 71.7°W and that of the latitudinal mi- grations is at about 30°S; these spatial symmetry axes are located at the subduction zone on the western margin of South America, where two major plates (the Nazca Plate and the South American Plate) converge.
基金the Ministry of Land Resources and the Ministry of Science and Technology for the research funding of the projects:SinoProbe 04,973 Project 2007CB411406 and 863 Project 2007AA06Z133
文摘A study of deep penetrating geochemistry--the surface exploration techniques for finding concealed mineral deposits--was carried out over the Spence porphyry copper deposit in Chile by Australian, Canadian and Chinese laboratories using selective weak leach methods and is briefly reviewed here. Erratic and weak copper anomalies were obtained above the Spence deposit, which is concealed below a thick piedmont gravel cover. In the literature, such patterns are common in most of the weak selective leach studies carried out over known buried deposits. During exploration in unknown area, such weak leach techniques lead to some success and many dry holes. In this paper, stronger selective leaching methods are developed for oxides and sulfides, which may be the stable end products transformed and accumulated by a mobile precursor phase carried upward through the overburden by gas or water through long spans of geological time. The data obtained by the methods developed in this paper produced more significant and consistent anomalous data than previous efforts. Consequently, the leach approaches described here may increase the effectiveness of deep penetrating geochemistry in exploration for con- cealed ore deposits.
基金Supported by The grant OAIC 394/10(to M.V.)from Hospital Clínico Universidad de Chile
文摘AIM:To analyze the association of three IL28B single nucleotide polymorphisms with response to therapy in Chilean patients infected with hepatitis C virus CV.METHODS:We studied two groups of patients with chronic CV infection genotype 1,under standard combined treatment with pegylated interferon plus ribavirin.One group consisted of 50 patients with sustained virological response,whereas the second group consisted of 49 null responders.In order to analyze the IL28B single nucleotide polymorphisms rs12979860,rs12980275 and rs8099917,samples were used for polymerase chain reaction amplification,and the genotyping was performed by restriction fragment lengthpolymorphism.RESULTS:The IL28B rs12979860 CC,rs12980275 AA and rs8099917 TT genotypes were much more frequently found in patients with sustained virological response compared to null responders 38%,44% and 50% vs 2%,8.2% and 8.2%,respectively.These differences were highly significant in all three cases(P < 0.0001.CONCLUSION:The three IL28B polymorphisms studied are strongly associated with sustained virological response to therapy in Chilean patients with chronic CV genotype 1.
基金Supported by Grants-in-Aid for Scientific Research on Priority Areas of the Ministry of Education, Culture, Sports, Science and Technology, Japan, No. 12218231 and 17015037
文摘AIM: To examine the presence of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) specimens collected from Colombia and Chile located in the northern and southern ends of the continent, respectively.METHODS: We examined 47 and 26 formalin-fixed and paraffin-embedded ESCC specimens from Colombia and Chile, respectively. HPV was detected using GP5+/GP6+ primer pair for PCR, and confirmed by Southern blot analysis. Sequencing analysis of L1 region fragment was used to identify HPV genotype. In addition, P16^INK4A protein immunostaining of all the specimens was conducted.RESULTS: HPV was detected in 21 ESCC specimens (29%). Sequencing analysis of L1 region fragment identified HPV-16 genome in 6 Colombian cases (13%) and in 5 Chilean cases (19%). HPV-18 was detected in i0 cases (21%) in Colombia but not in any Chilean case. Since Chilean ESCC cases had a higher prevalence of HPV-16 (without statistical significance), but a significantly lower prevalence of HPV-18 than in Colombian cases (P = 0.011) even though the two countries have similar ESCC incidence rates, the frequency of HPV-related ESCC may not be strongly affected by risk factors affecting the incidence of ESCC. HPV-16 genome was more frequently detected in p16 positive carcinomas, although the difference was not statistically significant. HPV-18 detection rate did not show any association with p16 expression. Well-differentiated tumors tended to have either HPV-16 or HPV-18 but the association was not statistically significant. HPV genotypes other than HPV-16 or 18 were not detected in either country.CONCLUSION: HPV-16 and HPV-18 genotypes can be found in ESCC specimens collected from two South American countries. Further studies on the relationship between HPV-16 presence and p16 expression in ESCC would aid understanding of the mechanism underlying the presence of HPV in ESCC.
文摘The tempo-spatial variation of seismic activity before great Chile Mw8.8 earthquake on February 27, 2010 is studied. Some results are as follows: ①Two types of seismic gaps appeared before the Chile MwS.8 shock. One is background gap of Mw≥8.0 earthquakes with 360 km length since 1900, the other is seismogenic gap formed by M≥5.5 earth- quakes with 780km length five years before the Chile earthquake; ②There was only one Mw7.1 earthquake in the middle and southern part of Chile from 1986 to 2010. The obvious quiescence of Mw≥7.0 earthquake is the long-term background anomaly for the Chile earthquake; ③ The quiescence of M≥6.5 earthquakes appeared in South American block and its vicinity during the period from 2007 to 2009, and the quietude state has been disappeared three months before the Chile Mw8.8 earthquake; ④ The deep and intermediate-depth earthquake activity has been noticeablely strengthened in the subduction zone of South American block since 1993; ⑤The great Chile earthquake shows that global seismicity is still in the active period of Mw≥8.5 earthquakes since 2004. Based on the characteristics of the former two active periods, several great earthquakes with Mw≥8.5 would take place in a few years. In addition, the circum-Pacific seismic belt would be the main region for Mw≥8.0 earthquakes.
基金funded by the National Natural Science Foundation of China(Nos.41306127 and 41276156)National Science Foundation of Shanghai(13ZR1419 700)+3 种基金the innovation Program of Shanghai Municipal Education Commission(13YE091)Research Fund for the Doctoral Program of Higher Education of China(20133104120001)Shanghai Universities First-class Disciplines Project(Fisheries)supported by Shanghai Oversea Teaching Scholar Program and SHOU International Center for Marine Sciences
文摘We applied solution-based ICP-MS method to quantify the trace-elemental signatures in statoliths of jumbo flying squid, Dosidius gigas, which were collected from the waters off northern and central Chile during the scientific surveys carried out by Chinese squid jigging vessels in 2007 and 2008. The age and spawning date of the squid were back-calculated based on daily increments in statoliths. Eight elemental ratios(Sr/Ca, Ba/Ca, Mg/Ca, Mn/Ca, Na/Ca, Fe/Ca, Cu/Ca and Zn/Ca) were analyzed. It was found that Sr is the second most abundant element next to Ca, followed by Na, Fe, Mg, Zn, Cu, Ba and Mn. There was no significant relationship between element/Ca and sea surface temperature(SST) and sea surface salinity(SSS), although weak negative or positive tendency was found. MANOVA analysis showed that multivariate elemental signatures did not differ among the cohorts spawned in spring, autumn and winter, and no significant difference was found between the northern and central sampling locations. Classification results showed that all individuals of each spawned cohorts were correctly classified. This study demonstrates that the elemental signatures in D. gigas statoliths are potentially a useful tool to improve our understanding of its population structure and habitat environment.
文摘AIM: To demographically and clinically characterize inflammatory bowel disease (IBD) from the local registry and update data previously published by our group.METHODS: A descriptive study of a cohort based on a registry of patients aged 15 years or older who were diagnosed with IBD and attended the IBD program at Clínica Las Condes in Santiago, Chile. The registry was created in April 2012 and includes patients registered up to October 2015. The information was anonymously downloaded in a monthly report, and the information on patients with more than one visit was updated. The registry includes demographic, clinical and disease characteristics, including the Montreal Classification, medical treatment, surgeries and hospitalizations for crisis. Data regarding infection with Clostridium difficile (C. difficile) were incorporated in the registry in 2014. Data for patients who received consultations as second opinions and continued treatment at this institution were also analyzed.RESULTS: The study included 716 patients with IBD: 508 patients (71%) were diagnosed with ulcerative colitis (UC), 196 patients (27%) were diagnosed with Crohn’s disease (CD) and 12 patients (2%) were diagnosed with unclassifiable IBD. The UC/CD ratio was 2.6/1. The median age was 36 years (range 16-88), and 58% of the patients were female, with a median age at diagnosis of 29 years (range 5-76). In the past 15 years, a sustained increase in the number of patients diagnosed with IBD was observed, where 87% of the patients were diagnosed between the years 2001 and 2015. In the cohort examined in the present study, extensive colitis (50%) and colonic involvement (44%) predominated in the patients with UC and CD, respectively. In CD patients, non-stricturing/non-penetrating behavior was more frequent (80%), and perianal disease was observed in 28% of the patients. There were significant differences in treatment between UC and CD, with a higher use of corticosteroids, and immunosuppressive and biological therapies was observed in the patients with CD (P < 0.05 and P < 0.01). Significant surgical differences were also observed: 5% of the UC patients underwent surgery, whereas 38% of the CD patients required at least one surgery (P < 0.01). The patients with CD were hospitalized more often during their disease course than the patients with UC (55% and 35% of the patients, respectively; P < 0.01). C. difficile infection was acquired by 5% of the patients in each group at some point during the disease course. Nearly half of the patients consulted at the institution for a second opinion, and 32% of these individuals continued treatment at the institution.CONCLUSION: IBD has continued to increase in the study cohort, slowly approaching the level reported in developed countries.
文摘Background: Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio?economic, cultural and environmental characteristics. However, green areas, including original fragments, can help to conserve native diversity, improving the functioning of these artificial systems in the long term. Urban areas can still provide habitats usable by wild birds, however the structural charac?teristics of the habitat formed by different types of green area differ, and therefore dissimilar bird diversities are to be expected. The object of this study was to characterise the α and β diversities of birds in different green areas and to analyse how diversity relates to ten variables that characterise the habitat.Methods: We studied the green areas in the city of Temuco, southern Chile(Park, Square and Median strips of main streets), evaluating the variables:(a) surface area,(b) vegetation,(c) estimated human impact as the proportions of vegetation and bare soil by area, and the vehicle traffic. The bird assemblage structures were characterised by α(intra?environment) diversity and β diversity(between environments) and the statistical analysis identified the environmen?tal variables related with the presence and abundance of birds. A statistical model was constructed to describe the contribution of the variables to bird diversity.Results: We found significant differences between the diversity of bird species in the three types of green area. The β showed medium to high similarity between the different study units. There was a negative correlation with bare soil areas; the correlations with vehicle flow, plant structure and tree and shrub cover were not significant, meaning that these variables did not explain the variation in the richness of bird species between the green areas. However the surface area did explain this variation presenting a positive potential relation. There was also a high correlation with the origin(native) of shrub species.Conclusions: The bird diversity varied significantly according to the type of urban green area. The environmental variables presenting significant correlations with bird diversity were: surface area, native species of shrub stratum, shrub cover, and bare soil area. The best multiple regression model showed that the three most important variables for bird diversity are the surface area of the green area, the cover of the shrub stratum and the presence of native shrub species.
基金supported by Fondecyt No. 1080294 and Fondecyt 1110719 (R Barra)
文摘This pilot study documented the occurrence and levels of brominated flame retardants in the tissues of farmed and wild salmon in southern Chile.Samples of Coho salmon and rainbow trout were obtained from fish farms,rivers and lakes in the Patagonia in Aysen Region,Chile.The samples were analyzed by Gas Chromatography Negative Chemical Ionization Mass Spectrometry for the different polybrominated diphenyl ether(PBDE) congeners.Contaminants were observed in all the samples,and the congeners BDE 17,28,47 and 66 were observed in all both farmed and wild samples.The concentrations were higher in the farmed Coho salmon,presenting significant differences with wild salmon.The levels reached 182 pg/g wet weight(ww) vs.120 ww.In the case of the rainbow trout,the concentrations were lower,although the congener profile was quite similar.The levels reached an average of 100 pg/g ww in the farmed fish versus 110 pg/g ww in wild fish,and no significant difference was observed between the species.In both species,the congener with the highest concentration was BDE 47.Based on this information,the BDE ?ow was estimated for commerce,which is a form of pollutant transport not usually considered in POP pollution studies.A preliminary estimation indicated that the quantity of PBDEs mobilized by commerce was in the order of kg,and in the case of Chile might reach almost 1 kg.
文摘Based on a qualitative research restricted to aging processes in Chile, the paper presents the experience and significance of dependence in elderly men and how it is related with the social construction of old age. It is important to know how the identity of aging is configured when facing such a significant biographical and social landmark as the loss of functionality in later life. When analyzing the social construction of dependence in elderly men, three aspects of that configuration stand out: first, the way in which they understand and signify their situations of illness, physical problems, disability, and evaluation of their health;second, the characteristics of the social significant contexts in which disability or physical problems become evident;and third, the actions, roles or activities that they perform in those contexts, which are valued differently according to the experiences of dependence or autonomy. Dependence in elderly men does not appear as a static condition, but rather as a passage from physical-biological conditioners to the social context in which their everyday actions take place. So the agency of the dependence, its construction, experience and significance is the understanding of the social phenomenon of old age.
基金funded by ANID—Millennium Science Initiative Program (No. NCS2022_053)。
文摘Traditional Chinese medicine(TCM) arrived from China to Latin America and the Caribbean in the 1840s due to the massive migration of Chinese people to the region. In a few years, the press noticed the presence of Chinese herbalists practicing in different cities and countries regardless of the demographic weight of the Chinese community. The fascination with Chinese doctors implicated not only the press but also the literature, a phenomenon particularly observed in Cuba. In the first decades of the 20th century, the reactivation of Chinese immigration to the region fostered an anti-Chinese climate that materialized in more significant migratory restrictions and control of their businesses, such as what happened with Chinese herbalists. These herbalists who practiced inside and outside the Chinese community started to object to criticism and persecution by the conservative press and professional doctors. Despite this, Chinese doctors will continue to maintain their support of a significant number of ill persons. This work seeks to illuminate the historical relevance of TCM in Latin America and the Caribbean, focusing on the cases of Peru, Chile, and Cuba. This last country was far from China culturally and geographically, but as in many other small towns in the region, Chinese medicine presented an alternative to the treatment of illnesses.
基金supported by Environmental Protection Research Fund for Public Interest (No.201209040)
文摘Great differences in hazard and losses were shown from two tsunamis, both generated in Chile, one in 1960 and the other in 2010. Numerical simulation was applied to the tsunami analysis. The fault dislocation of the seafioor was assumed to equal to the initial tsunami wave field, which can be calculated by the formula of fault dislocation in the elastic isotropic half-space. The linear long wave theory was used as the tsunami hydrodynamic model, and the finite difference method and leap-frog scheme were selected for solving the equations. The accuracy of the simulated results was verified by the observed data in five tide gauges. By means of two scenario tsunamis, the analytical results show that the earthquake magnitude, bathymetry in rupture zone and rapid release of warning information in 2010 tsunami are the main explanations of the aforementioned great difference.
文摘Aging and widowhood signal a real and symbolic landmark of change toward new vital experiences of elderly people. In the aging experience of women, there are three social age markers that participate directly in the construction of their identity as women during old age: menopause, work and widowhood. The present paper reports the results of a research on widowhood in old age and the experience of aging in elderly women in Chile. Through a qualitative methodological strategy, in depth biographic interviews were held with elderly people who were widowed after reaching 60 years of age, centering the analysis on its meanings on the body, health and death in old age, highlighting sociocultural aspects of the aging and widowing processes. Approaching widowhood in old age shows us not only a person who has lost a husband, but also what it means to be an elderly woman in a life experience continuum that also brings about key changes to understand the aging process of people, because marital relations can get to be determining factors for the construction of the identity of women and their experience of the aging process.
文摘We assessed the effects of plantations of exotic trees (Pinus radiata, Eucalyptus globulus, and Populus nigra) on plant biodiversity in the temperate zone of the biodiversity hotspot of Central Chile. This region has suffered from intense deforestation in favor of plantation establishment in the major part of the coastal area since the neoliberal turn in 1973. The approach presented aimed to analyze plant biodiversity on the α-, β- and γ-scale. Furthermore, a plantation evaluation index was applied in order to provide quantitative figures on management practices. Species richness is reduced by 50% below plantations. Diversity and evenness index values are also significantly reduced. Analyses on β-similarity indicate that plantations do not host species absent in adjacent native forests, and no additional habitat heterogeneity is gained. On the γ-scale, plantations lower the number of total species observed;especially of endemic species. The abundance of species considered as invasive is significantly higher and frequently, invasive plants dominate the understory. The evaluation index attests rather poor plantation management in Central Chile since plantations are grown as monocultures, natural elements and native species are lacking at specific sites and plantations are insufficiently connected to native plant formations at the landscape scale. Results give much concern since deforestation processes as observed in our study area is about to begin in Patagonia as well. If management practices from the temperate zone are adopted in Patagonia, a considerable decline in plant biodiversity has to be expected there.
文摘Background: Adolescent obesity is associated with high cardiovascular and metabolic risk. Western diet and reduced physical activity are strong environmental determinants. The “Health Production” model posits that individuals born with a certain amount of health stock, which depreciates over life, but can be augmented by individual behaviors, including exercise and dieting. Objective: To study the association between health production and obesity in a random sample of 1692 Chilean adolescents (14.8 ± 0.7 years old), and to study the effect of gender and socioeconomic characteristics on health production. Method: We used an indicator that considered the quality of food intake and physical activity, establishing three categories: good (GHP), intermediate (IHP) and poor health producers (PHP). Multivariate analysis was used to study the odds of obesity and good health production. Results: There was 31% of GHP, 32% of IHP and 38% of PHP. Obesity (Adj. OR: 1.59;95%CI: 1.04 - 2.42) and abdominal obesity (Adj. OR: 2.24;95%CI: 1.35 - 3.40) were significantly higher in the PHP group, compared to the GHP and IHP group. Health production was significantly associated with socioeconomic factors and gender. Female sex and coming from a less wealthy household significantly reduced the odds of good health production. Conclusions: Poor health production in adolescence, as defined by food intake and physical activity, depreciates individuals’ “health stock”, increasing the risk of obesity. In our sample, health production was strongly associated with socio-economic factors and gender.
基金supported by Grants DI 037.484/2013 and DI 37.370/2014 from the Dirección de Investigación,Vice-rectoría de Investigación y Estudios Avanzados,Pontificia Universidad Católica de Valparaíso,Chilesupported in part by Grant SA10I20005 from the National Fund for Health Research and Development(FONIS/MINSAL of CONICYT)
文摘This study analyze the relation between body composition, physical activity (PA), and sex in Chilean children from rural and urban public educational institutions. The prevalence of obesity (according to BMI) was 30.88% in urban children and 28.93% in rural children. Central obesity presented mainly in the rural girls. Approximately 90% of the participants reported 〈7 h of PA/week, regardless of residential area. In addition, central fat was strongly associated with rural residence; the children reported lower PA levels, and they presented a higher prevalence of central fat. The results reflect the need to implement programs to improve PA conditions in the child urban-rural population.
文摘We undertook a boat expedition to explore the geological framework of a very remote,lesser-known island,in the Chilean Patagonia:the Diego de Almagro Island(latitude S51°330').This uninhabited,ca.400 km^2 Island is one of the very rare exposures of the Mesozoic accretionary subduction complex along the Chilean margin.Unstable weather,strong winds,steep topography,and very dense vegetation make an on-land mission difficult.Careful preparation based on high-resolution satellite images is advised to optimize shore access and minimize risks of injury.Despite a relatively important degree of regional reequilibration of metamorphic assemblages due to sluggish exhumation through the forearc crust,our results have shown that the island is composed of a nappe stack of ocean-floor derived slivers of metasedimentary units that exhibit very different pressure-temperature-time paths during burial by subduction under the Chilean margin and subsequent exhumation.These rocks are witness to a complex thermal evolution of the subduction zone between Jurassic and Cretaceous times from granulite facies to blueschist facies conditions as well as multiple episodes of accretion at ca.35-40 km in depth for almost100 Ma over the Mesozoic era.