bluuebunny/crossref_metadata_2025 huggingface dataset:
SUPEROXIDE DISMUTASE ISOENZYMES, GLUTATHIONE PEROXIDASE AND SELENIUM IN BLOOD FROM HLA‐B27‐POSITIVE AND ‐NEGATIVE SUBJECTS
Authors: Marklund S. L. , Repo H. , Koskimies S.
Published: August 2010

We studied the activity of superoxide dismutase (SOD) isoenzymes (CuZnSOD, cyanide‐resistant Mn‐SOD and extracellular SOD), the concentration of plasma selenium (P‐Se), and the activities of CuZn‐SOD and glutathione peroxidase (GSHPx) in erythrocytes of 10 HLA‐B27‐positive and 10 HLA‐B27‐negative subjects whose sera had shown high and low chemokinetic activity, respectively, on migration of polymorphonuclear leukocytes (PMN) in vitro. No significant difference was found between the groups, suggesting that the enhanced chemokinetic activity of HLA‐B27‐positive sera does not derive from an aberration in serum anti‐oxidant potentials. The results were also analysed on the basis of HLA‐DR specificities: HLA‐DR4‐positive plasma samples had significantly lower levels of Se than HLA‐DR4‐negative ones. We therefore carried out a second series of experiments with sera of 37 subjects; the levels of P‐Se in HLA‐DR4‐positive and ‐negative groups were much the same, as were the activities of GSHPx. The data suggest that there is no gross aberration in P‐Se concentration in HLA‐DR4‐positive subjects.
HUMAN ALVEOLAR MACROPHAGES AND MONOCYTES GENERATE THE FUNCTIONAL CLASSICAL PATHWAY OF COMPLEMENT IN VITRO
Authors: Hetland G. , Johnson E. , RøYset P. , Eskeland T.
Published: August 2010

Binding of labelled protein to EIgM kept with macrophage or monocyte cultures with 3H‐leucine under serum‐free conditions, shows that de novo synthesis of protein with affinity to EIgM takes place. We find that monoclonal anti‐C3c and anti‐C3g antibodies and polyclonal anti‐C4 and anti‐C5 antibodies bind to such erythrocytes. This demonstrates that C4b, C3b and iC3b are deposited on the EIgM. Additional evidence for complement synthesis is the increase in binding of anti‐C4 antibodies to EIgM when the incubation time was increased from 48 to 96 hours. Stimulation of the mononuclear phagocyte cultures with ET was necessary to obtain significant amounts of erythrocyte‐bound complement proteins. From these results we conclude that the functional classical pathway of complement is produced in vitro by the monocytes and macrophages.
BRAIN AND SPINAL CORD LESIONS IN ENCEPHALITOZOONOSIS IN BLUE FOXESTransmission and Scanning Electron Microscopic Studies
Authors: BJERKÅS INGE
Published: August 2010

The brains and spinal cords from 3 young blue foxes suffering from acute to subacute encephalitozoonosis, were examined by transmission and scanning electron microscopy. Parasitophorous vacuoles (PV) were demonstrated more frequently in vascular smooth muscular cells than in endothelial cells. The present study also indicated that the parasite has great affinity for neurons, including their processes. In addition, PV occurred in macrophages and probably also in intravascular monocytes. PV were readily differentiated from phagosomes by the bleb formations of the limiting membrane. An accumulation of host cell mitochondria near the PV in areas where developmental stages were attached, was a most striking feature. The inflammatory lesions, mainly of the granulomatous type, were almost constantly associated with the presence of released parasites, both in vascular walls and the nervous tissue. Phagocytosed parasites were probably killed by the lysosomal enzymes, although the spores were only slowly degraded.
The Mediating Effects of Stress and Coping on Depression Among Adolescents in China
Authors: Sun Ying , Tao Fangbiao , Hao Jiahu , Wan Yuhui
Published: August 2010

AIMS:  To explore gender differences in Chinese adolescent depression related to the mediating effects of stress and coping.

METHODS:  The data were collected using a cross‐sectional design from a multisite follow‐up investigation of adolescent physical and psychological study carried out in China. The study population consisted of 17,622 students aged from 11 to 22 years of age in junior high, senior high schools, and colleges/universities from eight large cities in China.

RESULTS:  Overall, 44.3% of the sample reported depression during the past week. Male adolescents were more likely to have depression than female counterparts (46.8% versus 41.7%), especially those aged <15 and >17 years of age. Overall, stress in boys was statistically higher than that of girls. Boys experienced high levels of stress from school, family, health, and romantic domains, while girls suffered a higher level of peer stress. A multivariate logistic regression model showed that a high level of total stress was significantly associated with increased risk for depression, while peer stress and positive coping style were protective factors for depression in both boys and girls in China.

CONCLUSIONS:  Unlike their Western counterparts, Chinese boys suffered more depression than girls, which is partly due to more stressful life events and less positive coping style. Our study has important implications for health officers and public health professionals to pay much attention to the relationship between stress and coping style in prevention on adolescent depression.
The Protection-Neutrality Dilemma in Humanitarian Emergencies: Why the Need for Military Intervention?
Authors: Weil Carola
Published: August 2010

For humanitarian organizations such as the United Nations High Commissioner for Refugees (UNHCR), the recent evolution of military engagement in Complex Humanitarian Emergencies has been a mixed blessing. This article examines the protection-neutrality dilemma confronting UNCHR in the face of increased military humanitarian action. The conceptual framework presented here suggests that military forces may in fact act as an important “norms entrepreneur,” influencing how protection norms affect international responses to humanitarian emergencies. The linking of forced migration and security has generated a host of challenges for civil-military relations and raises a number of concerns for UNHCR regarding the legitimacy, ethics and operational viability of military interventions in such crises.
Immigrants and ‘New Poverty': The Case of Canada
Authors: Kazemipur Abdolmohammed , Halli Shiva S.
Published: August 2010

Studies of the economic status of recent immigrants to the United States have questioned the generalizability of some earlier findings based on assimilation theory. In Canada, however, little research has been done on this issue, and that has left mixed results. The present study attempts to address the economic performance of immigrants in Canada through an examination of their poverty status. This is particularly important now because, since the late 1980s, many industrial nations including Canada have been subjected to an unexpected surge of poverty known as ‘new poverty.' The findings indicate that immigrants in Canada are consistently overrepresented among the poor; that their poverty rates are particularly high in larger cities, which have larger concentrations of immigrants; and that among immigrants, the poverty rates are higher for visible minorities, who are mostly recent immigrants. One particularly surprising finding was that the second-generation immigrants, who were expected to outperform their parents, had higher poverty rates. A series of logistic regression models are developed to shed some light on the possible reasons behind these trends. Of the three sets of potential contributors – human capital, assimilation and structural factors – the first two were found more relevant. The models also revealed that the human capital factors were less rewarding for immigrants than natives.
Local Economic Opportunity and the Competing Risks of Internal and U.S. Migration in Zacatecas, Mexico
Authors: Lindstrom David P. , Lauster Nathanael
Published: August 2010

This article uses a competing risks model to examine the effects of origin economic conditions on the probability of temporary U.S. and internal labor migration in the Mexican state of Zacatecas. We measure origin economic conditions with municipal-level indices of employment and small-scale investment opportunities that we constructed from population and economic census data. The results of our analysis demonstrate the important influence of local employment and investment opportunities on migration outcomes. Controlling for the prior municipal rate of U.S. return migration and other factors, positive opportunities for small-scale investment are associated with a higher risk of temporary migration to the United States. This result is consistent with investment oriented migration predicted by the new economics of labor migration theory. We also find comparable social network effects for both internal and U.S. migration. Having social ties to active migrants of one type (U.S. or internal), encourages migration of the same type and discourages migration of the other type.
The North American Naturalization Gap: An Institutional Approach to Citizenship Acquisition in the United States and Canada
Authors: Bloemraad Irene
Published: August 2010

Using 1990 U.S. Census 5% PUMS and 1991 Canadian Census 3% public and 20% restricted microfiles, this article demonstrates the existence of a North American naturalization gap: immigrants living in Canada are on average much more likely to be citizens than their counterparts in the United States, and they acquire citizenship much faster than those living south of the border. Current theories explaining naturalization differences - focusing on citizenship laws, group traits or the characteristics of individual migrants - fail to explain the naturalization gap. Instead, I propose an institutional approach to citizenship acquisition. States' normative stances regarding immigrant integration (interventionist or autonomous) generate integrated or disconnected institutional configurations between government, ethnic organizations and individuals. Evidence from a case study of Portuguese immigrants living in Massachusetts and Ontario suggests that in Toronto government bureaucrats and federal policy encourage citizenship through symbolic support and instrumental aid to ethnic organizations and community leaders. In contrast, Boston area grassroots groups are expected to mobilize and aid their constituents without direct state support, resulting in lower citizenship levels.
Portuguese Migrants in the German Labor Market: Selection and Performance
Authors: Bauer Thomas , Pereira Pedro T. , Vogler Michael , Zimmermann Klaus F.
Published: August 2010

The labor market performance of Portuguese workers in Germany is analyzed in this article. While previous work has compared wages and characteristics of migrants to natives only, this study also matches the data set with an equivalent survey from the sending country. The findings show that Portuguese migrants as a whole are negatively selected, with the exception of blue-collar workers, the largest group among the movers. The finding that Portuguese migrants earn more than comparable Germans indicates that they have higher unobservable skills.
Binding the Generations: Household Formation Patterns among Vietnamese Refugees
Authors: Haines David W.
Published: August 2010

Much of the analysis of refugee and immigrant adaptation has stressed the interaction of prior experience with the requirements of life in a new country. For refugees, that interaction has often been jarring because of the after-effects of their flight and their relative inability to prepare for a new life in a new country. Yet refugees have often done rather well in economic terms in that new country. The reasons for that relative success have been phrased in cultural terms {e.g., the predisposition toward education) and in general socioeconomic terms (e.g., refugees as educated and skilled).

This article examines a set of factors that lie between these customary cultural and socioeconomic categories. Specifically, the paper examines key features of household formation among Vietnamese refugees. An examination of historical data from southern Vietnam indicates patterns in household formation that appear durable over time yet are not shared across the breadth of Vietnam and cannot thus be viewed as “cultural” in the usual sense. A comparison of the historical data with recent national survey data on refugees in the United States indicates that these patterns continue among Vietnamese refugees and are - as compared to other refugees - distinctive to them. These patterns of household formation provide Vietnamese refugees with important options in adaptation to a new country.
Managing Contradiction: Civic Stratification and Migrants’ Rights
Authors: Morris Lydia
Published: August 2010

Political and academic interest in cross-national migration has generated two very different and potentially polarized positions. One perspective emphasizes the continuing power or the nation state, while the other sees migration, and more specifically migrants’ rights, as the manifestation of an emergent ‘post-national’ society. This article offers a conceptual framework which addresses this polarization through the concept of civic stratification (Lockwood, 1996). In illustrating its application, the study shows how such an approach goes beyond a traditional citizenship framework (e.g., Marshall, 1950) in considering degrees of partial membership, but remains cautious with respect to claims about universal, transnational rights.
Rights or Identity? Naturalization Processes among “Labor Migrants” in Germany
Authors: Diehl Claudia , Blohm Michael
Published: August 2010

The determinants of the decision to naturalize for first and second generation “labor migrants” in Germany are examined. We assume that Turkish migrants’ comparatively high naturalization rate cannot be explained by the legal advantages they gain by naturalizing. We argue instead that naturalization offers an opportunity for individual upward mobility to Turkish migrants who have achieved a high level of individual assimilation. Using data from the GSOEP, we show that individual assimilation does in fact promote naturalization for Turkish migrants, but not for members of other ethnic groups, which generally have higher status within German society.
Enclaves and Entrepreneurs: Assessing the Payoff for Immigrants and Minorities
Authors: Logan John R. , Alba Richard D. , Stults Brian J.
Published: August 2010

Self-employment and work in sectors with high concentrations of owners and workers of the same ethnicity have been identified as potential routes of economic success for immigrants. This study uses 1990 census data to assess the effects of self-employment, ethnic employment, and their interaction on the odds of being at work, on number of hours worked, and on earnings of individual members of several representative groups. These groups include Cubans in Miami; African Americans, Puerto Ricans, Koreans, Chinese and Dominicans in New York; and African Americans, Koreans, Chinese, Mexicans and Salvadorans in Los Angeles. Work in ethnic sectors of the economy has no consistent effects, although work in their niche in the public sector offers greater rewards than any other type of employment for African Americans and Puerto Ricans. Findings are mixed for self-employment, and its estimated effect on earnings depends on model specification. We conclude that the self-employed work longer hours but in many cases at lower hourly rates. The effects of self-employment are the same in ethnic sectors as in the mainstream economy.
Foreign Scientists at the National Institutes of Health: Ramifications of U.S. Immigration and Labor Policies
Authors: Díaz-Briquets Sergio , Cheney Charles C.
Published: August 2010

This article describes the findings of a study undertaken to shed light on some of the factors that determine the employment of foreign biomedical scientists in the United States by examining their presence at the National Institutes of Health (NIH). NIH was selected as the focus of the study for its unique combination of characteristics. It is a federal agency with the ambiance of academe that carries out biomedical research and training internally while supporting like activities externally through grant- and contract-based linkages with a host of academic institutions and biotechnology firms in the United States and abroad. Over a two-year period, in-depth interviews were conducted with more than 200 stakeholders at the NIH campus and elsewhere, as well as ethnographic observations. The study identified several hitherto unreported important functions that NIH plays in facilitating the inflow of talented foreign scientists to meet its manpower needs and those of the broader national economy.
The Politics of Migrants’ Transnational Political Practices
Authors: Østergaard-Nielsen Eva
Published: August 2010

This article critically examines transnational political engagement of migrants and refugees in local, national and global political processes. Based on inductive reading of existing scholarship and in particular the author's own research on Turks and Kurds in Europe, the article discusses key concepts and trends in our understanding of why, how and with what consequences migrants engage in transnational political practices. These practices, this article suggests, are influenced by the particular multilevel institutional environment, which migrant political actors negotiate their way through. This environment includes not only political institutions in the sending and receiving country, but also global norms and institutions and networks of other nonstate actors. Finally, the article argues for critical examination of the democratic transparency and accountability of migrants’ transnational networks in any analysis of their long and short-term impact on domestic and global politics.
Calling upon the Sacred: Migrants’ Use of Religion in the Migration Process
Authors: Hagan Jacqueline , Ebaugh Helen Rose
Published: August 2010

The role of religion in the stages of the migration process has been overlooked by both immigration and sociology of religion scholars. This article draws on the migratory and religious history of a transnational Maya community with members in the western highlands of Guatemala and Houston, Texas. Drawing on field research of Mayas in both the sending and receiving areas, we show how migrants use religion in the following stages of the migration process: 1) decisionmaking; 2) preparing for the trip; 3) the journey; 4) the arrival; 5) the role of the ethnic church in immigrant settlement; and 6) the development of transnational linkages.
Effects of Government Policy on Internal Migration in Peninsular Malaysia: A Comparison between Malays and Non-Malays
Authors: Chitose Yoshimi
Published: August 2010

Do policies aimed at reducing ethnic inequality affect ethnic-specific migration? This article examines the effects of the New Economic Policy on first migration experiences of individuals in Peninsular Malaysia. Using life-history data from the Second Malaysian Family Life Survey, I analyze whether the policy affected migration of individuals and how the effect differs between the Malays and non-Malays for men and women. I found that the policy had positive effect on migration of both men and women, regardless of ethnicity. There is weak evidence that the NEP was ethnic-specific in affecting migration, while NEP was not sex-specific in affecting migration.
Cultural Influences on Immigrant Women's Labor Force Participation: The Arab-American Case
Authors: Read Jen'nan Ghazal
Published: August 2010

Research on the economic activity of immigrant women has flourished in recent years. The current study extends this literature to examine the labor force activity of Arab-American women, a group whose labor market experiences provide an exception to hitherto accepted theoretical explanations. The employment rates of Arab immigrant women rank among the lowest of any immigrant group, while the rates of native-born Arab-American women resemble those of U.S.-born white women. This study examines potential explanations for these differences using data from the U.S. Census and a national mail survey of Arab-American women. Contrary to findings for other immigrant groups, differences among Arab-American women cannot be explained by their human capital characteristics or family resources, but are almost entirely due to traditional cultural norms that prioritize women's family obligations over their economic activity, and to ethnic and religious social networks that encourage the maintenance of traditional gender roles. This study concludes by underscoring the need for additional research on the impact of culture on immigrant women's employment.
A Second Look at Self-employment and the Earnings of Immigrants
Authors: Bradley Don E.
Published: August 2010

Portes and Zhou (1996) present evidence to suggest that self-employment may impact the economic fortunes of immigrant groups by generating a relatively large number of very high earners. The present analysis seeks to extend and clarify the very high earner thesis using 1990 U.S. census data. Findings across 41 immigrant samples are generally consistent with expectations. However, in the majority of cases the effect of self-employment is due in whole or substantial part to the earnings of professional specialists. Findings are consistent with a very high earner model of nonprofessional specialist self-employment in eleven immigrant subsamples.
Emigration, Housing Conditions, and Social Stratification in China
Authors: Liang Zai , Zhang Toni
Published: August 2010

Using data from the 1995 China 1% Population Sample Survey, this article examines the impact of international migration on housing conditions in China. We find that international migration affects housing conditions differently in cities, towns, and rural areas. In rural areas, the impact of emigration on housing conditions is seen primarily through the increase of housing space, whereas in cities the impact of emigration on housing conditions is mainly reflected in the improvement of facilities. Although having a cadre in the household continues to be an important factor, international migration has begun to challenge, and even rival, this legacy of social stratification in China.
Conceptualizing Simultaneity: A Transnational Social Field Perspective on Society
Authors: Levitt Peggy , Schiller Nina Glick
Published: August 2010

This article explores the social theory and consequent methodology that underpins studies of transnational migration. First, we propose a social field approach to the study of migration and distinguish between ways of being and ways of belonging in that field. Second, we argue that assimilation and enduring transnational ties are neither incompatible nor binary opposites. Third, we highlight social processes and institutions that are routinely obscured by traditional migration scholarship but that become clear when we use a transnational lens. Finally, we locate our approach to migration research within a larger intellectual project, taken up by scholars of transnational processes in many fields, to rethink and reformulate the concept of society such that it is no longer automatically equated with the boundaries of a single nation-state.
Measuring Undocumented Migration
Authors: Massey Douglas S. , Capoferro Chiara
Published: August 2010

This article reviews standard sources of demographic data-censuses, intercensal surveys, registration systems, and specialized surveys and describes their inability to provide accurate data on immigrants, particularly those without documents. We discern a need for data that can identify undocumented migrants and their characteristics, measure trends over time, support longitudinal research, compare the characteristics of migrants before and after they enter, provide sufficient sample sizes for detailed analyses, study transitions between different legal statuses and movements back and forth, and monitor the effects of policy changes on a timely basis. We suggest that the ethnosurvey design satisfies these criteria. We describe the theory, structure, and organization of the ethnosurvey and then describe its application in the Mexican Migration Project. We then highlight its application in other locations around the world and outline an agenda for future comparative research.
Does the “New” Immigration Require a “New” Theory of Intergenerational Integration?
Authors: Esser Hartmut
Published: August 2010

Starting from discussions on the validity of the classical assimilation concept, a general model for the explanation of different structural outcomes of interethnic relations is developed. The core of the model builds on the assumption that different outcomes are the often unintended and situation-logic results of (mis-)investments in and with ethnic and non-ethnic capital. Central initial conditions of the model are group size, social and cultural distances and the availability of social capital. The model specifies the mutual relations between these three constructs. Different variants of intergenerational integration of immigrants can thus be reconstructed as special cases of a general mechanism.
Political Incorporation among Immigrants from Ten Areas of Origin: The Persistence of Source Country Effects
Authors: Bueker Catherine Simpson
Published: August 2010

Using four years of data from the Current Population Survey, this study examines the effect of country of origin on two types of political incorporation among immigrants – citizenship and voting – in the contemporary United States. Results show that country of origin is a statistically significant predictor of citizenship acquisition for nine of ten immigrant groups and for voter turnout for five of ten groups, net of income, education, length of residence in the United States, and other demographic characteristics. The findings also suggest that country of origin matters as much for how it interacts with other key characteristics, such as education and income, as for the independent influence it exerts on these two political processes. For immigrants from most countries under examination, lower levels of education and income discourage citizenship acquisition. An exception is found among Britons, for whom lower levels of income encourages naturalizing. In the voting process, higher levels of education encourage voter turnout for most immigrant groups. Though country of origin has a greater effect on naturalizing than on voting, it significantly impacts both types of political incorporation. The differing effects of country of origin and other demographic factors on naturalizing and voting, respectively, suggest the two processes are distinct from one another.
Getting Ahead in the Capitalist Paradise: Migration from China and Socioeconomic Attainment in Colonial Hong Kong
Authors: Chiu Stephen W. K. , Choi Susanne Y. P. , Ting Kwok-fai
Published: August 2010

This article examines the initial labor market outcome and the subsequent mobility process of Chinese immigrants in Colonial Hong Kong using complete work history data and event history modeling. Contrary to the rhetoric that Hong Kong is a capitalist paradise for adventurers, the data showed that immigrants were penalized in their initial class placement, subsequent mobility, and current income attainment. Differences in educational attainment and the lack of transferability of pre-migration human capital partly explained the attainment gap between immigrants and the natives. Yet the disadvantage of immigrants was also embedded in the local economic structure. The process of deindustrialization significantly lowered the chance of immigrants getting good first jobs when entering the labor market. Moreover, since deindustrialization benefited the natives by providing them with more opportunities in the service sector, it inadvertently widened the gap in upward mobility chances between natives and immigrants.
Rethinking Sanctuary: The Canadian Context, 1983–2003
Authors: Lippert Randy
Published: August 2010

The first comprehensive study of sanctuary in Canada identifies 36 sanctuary incidents since 1983. Through 46 personal interviews with sanctuary providers and examination of some 1,600 documents, sanctuary in the Canadian context is revealed to be less a national religious movement or network and more an array of temporary local incidents occurring largely independent of one another and of the now expired U.S. sanctuary movement. These sanctuary incidents have resulted as much from local community as church-based efforts, have mostly yielded positive outcomes for migrants involved, and are increasing in prevalence. Implications of these findings for understanding sanctuary are discussed.
What Human Capital, Which Migrants? Returned Skilled Migration to Slovakia from the UK
Authors: Williams Allan M. , Baláž Vladimir
Published: August 2010

This article contributes to the understanding of skilled labor migration by exploring some of the differences in the economic behavior of three contrasting groups of returned skilled labor migrants from Slovakia to the United Kingdom: professionals and managers; students; and au pairs. Formal professional experiences and training provide only limited understanding of the value of working/studying abroad. Instead, there is a need to look at particular competences, such as interpersonal skills and self-confidence, as well as the role of social recognition. The empirical results also emphasize the importance of spatiality and temporality when analyzing skilled labor migration.
Fluorescent‐based Solid Sensor for HSO4− in Water
Authors: Tan Chaoliang , Wang Qianming , Ma Lijun
Published: August 2010

In this report, we have shown that the encapsulation of the terbium 2‐methylimidazole‐4,5‐dicarboxylic acid complex into inorganic host tetraethoxysilance is considered to be an efficient way for the design of anion sensors. Strong green emission still can be observed when it disperses in pure water. It was found that the luminescence of hybrid material was selectively turned off rapidly (1 s) by hydrogen sulfate compared with the addition of different anions such as F−, Cl−, Br− and I−. Thin film was successfully prepared and also could be a promising tool for recognizing HSO4−.
The Marine Cretaceous in the Western Part of the Tarim Basin of Xinjiang and Its Depositional Environments
Authors: Yichun Hao , Xuelu Zeng , Xianpu Guo
Published: August 2010

Abstract The western part of the Tarim Basin in Xinjiang is one of the main areas in China where the marine Cretaceous is well developed. The Upper Cretaceous Yingjisha Group represented mainly by sediments of littoral, near‐shore neritic and estuarine facies is divided in ascending order into the Kukebai Formation, the Oytak Formation, the Ygezya Formation and the Tuylouk Formation.

For about thirty years, the basal beds of the Kukebai Formation had been considered to be the lowermost marine horizon of the Cretaceous in the western part of the Tarim Basin, which represents the earliest transgression of the Cretaceous Sea into this region. Recently, marine trace fossils, Ophiomorpha nodosa, O. tuberosa and Thalassinoides? spp. were found in abundance and fine preservation from the upper subcycle and upper part of the lower subcycle of the Kezlesu Group underlying the Kukebai Formation. The fact indicates that the marine transgression there took place earlier than the Kukebaian.

Process of transgression and regression and change of environment in the West Tarim Basin during the period from the late Early Cretaceous to the end of the Cretaceous is also discussed in this paper.
Applications of Remote‐Sensing Techniques in Peat Resource Investigations in Zoigê
Authors: Shizhong Fan
Published: August 2010

Abstract The paper presents an example of the application of remote‐sensing techniques in peat resource investigations. The study was carried out in the Zoigê region. The optimal imagery time ( during October) and the optimal band (MSS7) of Landsat data were selected. The preferred images were processed optically and by computer and interpreted in a comprehensive way. And in‐situ spectrum measurements and drilling verification were carried out. The identification signature of the peat bogs in Zoigê was defined. The feature of the identification signature for peat was that the peat bog area showed a dark tone with lower reflectance in images of the four MSS bands. The distribution range of peat bogs in the region was exactly located. The types of peat bogs were distinguished. The total peat area of 4038 km2 was defined with a total reserve of 5 billion m3. The result of the study indicates that the large‐area, small‐scale investigation of peat resources by use of satellite remote‐sensing data is an advanced method, by which the work efficiency can increase by about 20 times.
Finite Element Analysis of Crossing Flow in an Intersected Fracture by Penalty Function Formulation
Authors: Mingyou Chen , Kaiming Tian
Published: August 2010

Abstract On the basis of Navier‐Stokes equation, a digital analogue of crossing flow is carried out by means of finite element analysis performed through penalty function formulation. The results of the digital analogue are in good agreement with that of the previous hydraulic physical simulation. They both demonstrate the effect of “deflection flow” occurring at the fracture intersection that the fracture‐ water crossing flow deflects Δq into the wide fracture.
Tectonic Factors Favourable for the Formation of Evaporites in the Indosinian Period in Hubei and Its Neighbouring Areas
Authors: Shiruo Li
Published: August 2010

Abstract In the Indosinian period, the climate was scorching hot and the source of seawater was ample in Hubei and its neighbouring areas, so the basic conditions for the formation of evaporites were favourable. Under this prerequisite, the reason why salt deposits occurring in some third‐order tectonic units between the Jiangnan oldland‐upwarped zone and the Dabashan upwarped zone differ in degree of development is mainly due to the tectonic factors during sedimentation. If favourable tectonic factors are present, large amounts of evaporites will form; on the contrary, they will not.
An Experimental Study on Three Quaternary Phases in the Fe‐Sn‐Sb‐S System: Pb‐Free Franckeite, Pb‐Free Cylindrite and (Fe, Sb)‐Ottemannite s.s.
Authors: Jiuling Li , Jiashan Huang , Kezi Zhou , Guilan Zhang
Published: August 2010

Abstract Experimental studies on the two solid solutions franckeite s.s. and cylindrite s.s. yielded among others the Pb‐free endmembers of franckeite and cylindrite respectively. In these endmembers the lead content of the two mineral phases are completely substituted by bivalent tin. A third phase, ottemannite s.s. with (Fe, Sb)‐bearing compositions, was further identified in the Pb‐free 4‐component system Fe‐Sn‐Sb‐S. Pb‐free franckeite and cylindrite could only be synthesized as homogeneous phases at high temperatures. The ottemannite s.s. was obtained at 600°C but an extensive existing range was also confirmed at temperatures below 500°C.

The phase relations were discussed in the pseudoternary subsystem SnS‐SnS2‐FeSb2S4. The following sequence of Pb‐ free phases and phase assemblages were observed under increasing Sn4+ content at 600°C : herzenbergite (SnS)+franckeite, franckeite, franckeite+cylindrite, cylindrite, cylindrite+(Fe, Sb)‐ottemannite, (Fe, Sb)‐ottemannite, (Fe, Sb)‐ ottemannite+berndtite (SnS2). The assemblage cylindrite+berndtite was identified in synthetic systems involving Pb. The phase Fe, Sb‐ottemannite s.s. appears to be stable only under Pb‐de‐ficient and high sulfur fugacity conditions.
Medusoid Fossils from the Sinian Xingmincun Formation of Southern Liaoning Province
Authors: Zuomin Hong , Zhenfu Huang , Xinde Yang , Jing Lan , Bingcai Xian , Yajun Yang , Xiaoliang Liu
Published: August 2010

Abstract Abundant medusoid soft‐bodied metazoan fossils have been found in the Sinian Xingmincun Formation (with an isotopic age of 650 Ma) at Qipanmo, Qidingshan and Yangtun of the Dalian‐Jinzhou area, southern Liaoning Province; in addition, a number of macroscopic algal fossils have been discovered for the first time in the Getun Formation overlying the Xingmincun Formation. Medusoid fossils include 3 genera and 6 Species (all of which are new). Judging from their biological characters, these medusoid fossils are considered to have an intimate affinity with the Ediacara fauna in the terminal Precambrian of Australia, as their characters are close to each other. The authors suggest that these medusoids and the Edicara fauna might be the products of the same period. The discovery of the medusoid fauna in the Xingmincun Formation marts an important event in the evolution of the terminal Precambrian organisms in China, and it is of major practical significance in the study of the Sinian System of China and the correlation of the Sinian strata of northern and southern China.
The Sedimentologie‐Geotectonic Evolution in the Jiangsu Zhejiang Anhui Region
Authors: Bangdong Xia , Hongbo Lu
Published: August 2010

Abstract The Yangtze plate, extending from east to west in southern China, was formed about 800 Ma ago. Since the Sinian, two aulacogens trending east‐northeast and connected at the east ends, have been initiated in the Jiangsu‐Zhejiang‐Anhui region on the east margin of the plate with a sedimentary sequence up to 10,000 m in thickness. At a later stage of sedimentologic evolution, flysch and molasse were produced. The flysch was accumulated in the Late Ordovician, when the two aulacogens became bays that opened to the east; the clastic materials were derived from the Yangtze oldland on the northern and southern sides of the basins. The molasse was accumulated from the terminal Late Ordovician to the Middle Ordovician; the clastic materials came from an uplifted orogenic belt in the east. This indicates that a major change in the tectonic pattern of the basins has taken place.
On Deep Structures of the Xikang‐Yunnan Axis
Authors: Xuecheng Yuan
Published: August 2010

AbstractThrough recent study, the author considers that the north‐south‐trending Kangding‐Honghe tectonic belt is not a marginal uplift zone of the Yangtze Platform but a Te thy an‐type collisional tectonic belt of which the crust‐upper mantle can be structurally divided into three layers. The upper layer is the brittle upper crust, dominated by overthrusting and imbrication; the middle layer is the plastic lower crust and part of the upper mantle, represented by compression and shortening; and the lower layer is the upper, mantle, probably belonging to the Yangtze Platform in light of the thickness of the lithosphere.
Reef‐controlled Mineral Deposits in Southern China
Authors: Yunfu Zeng , Hongjun Tian
Published: August 2010

Abstract Reef‐controlled mineral deposits in southern China are divided into three types in this paper based on the relative importance of organic reefs in the ore‐forming processes; they are: the direct type, indirect type, and passive type. The case histories of several typical deposits are discussed. In studying reef‐controlled deposits, more attention should be paid to the function of synsedimentary faults in reef construction and mineralization and the importance of oil‐gas palaeoreservoirs in reef rocks for the formation of sulfide deposits, in addition to analysing the favourable sedimentary facies of mineralization.
Geochemical Anomaly at the Devonian / Carboniferous Boundary, Huangmao, Guangxi, China
Authors: Zhifang Chai , Xueying Mao , Shulan Ma , Shunliang Bai , Yaoqi Zhou , Jianguo Ma , Zhongshan Ning
Published: August 2010

Abstract The abundances of nearly 40 elements, Ir included, have been measured using radio‐chemical and instrumental neutron activation analysis (RNAA and INAA) across a Devonian / Carboniferous (D / C) boundary section at Huangmao, Guangxi, China. The Ir anomaly has been found in the D / C boundary bed. Its peak value is 156 ppt, richer by a factor of 12 than that in the underlying strata. Besides, as with Ir, other siderophile and chalcophile elements such as Au, Ni, Co, As and Sb are also enriched. The cause for the abundance anomalies of Ir and other elemets is discussed. Neither volcanic eruption nor extraterrestrial impact can explain it satisfactorily. The real mechanism for the anomalies awaits further study.
On the Age of the Dongtang Formation in the Hengyang Basin of Hunan and the Cretaceous and Tertiary Boundary
Authors: Shaozeng Guan
Published: August 2010

Abstract Since the coexistence of the Cretaceous and Palaeocene was ascertained in the Hengyang Basin of Hunan in the middle of the 1960's, the Cretaceous and Tertiary boundary has been discussed in several papers, but it still remains controversal. The points at issue are the connotation, stratigraphical position and lateral correlation of the Dongtang (or Chejiang) Formation.
Spectroscopic Features and Formation Conditions of Sphalerite in the Lead‐Zinc Deposit, Guangdong, China1
Authors: Di'en Li , Mingsheng Peng
Published: August 2010

Abstract Electron paramagnetic resonance spectra, absorption spectra, cathodoluminescence spectra and infrared spectra of sphalerite from the Lechang remoulded sedimentary lead‐zinc deposit have been studied so as to provide microscopic evidence for the formation conditions and mineralization stages of the deposit as well as the geochemical processes of mineralization. On the basis of thermodynamic calculations, the stable fields of sphalerite from different mineralization stages were determined and are shown in logfs2‐logfo2 diagrams? furthermore, the physico‐chemical conditions of mineralization and the properties of mineralization solutions are discussed so that reliability of the genetic information provided by the spectroscopy of sphalerite may also be verified. It is suggested that the temperature and pH value of the mineralization system decrease, and so do the fugacities of O2, S2, H2, and H2S and the activities of HS~ and SO2−4 from the early to late stages of mineralization.
Study of the Early and Middle Triassie Lower Yangtze Sea Basin
Authors: Guodong Zhang , Jingchang Zhu , Fukang Chou , Yiyou Wang , Junzhang Zheng
Published: August 2010

Abstract The Early and Middle Triassic primary lower Yangtze sea basin was formed before the Yangtze and Sino‐Korean blocks collided and were assembled, showing the characteristics of an open continental shelf‐continental margin sea. In order to provide evidence useful for oil and gas exploration in the studied region, this paper centres on the features of the sediments and their facies framework in the basin and the sedimentation parameters such as the deposition rate, palaeotemperature, palaeosalinity, palaeodepth of water and palaeocurrents of the basin.
Minerogenic Model of Chrysotile Deposits in Ultramafic Rocks
Authors: Pu Wan
Published: August 2010

Abstract Most chrysotile deposits occur in ultramafic rocks of the ophiolite suite. The chrysotile deposits discussed in the present paper were formed through metasomatism and infilling‐crystallization in a continental serpentinization environment after plate convergence, where ultramafic rocks were replaced by hydrothermal solutions consisting mainly of deep‐circulating heated water derived from atmospheric precipitation. The critical state for the formation of asbestos in ultramafic rock bodies might be reached by superposition of multiple stages of serpentinization. Favourable fracture systems and relatively stable geological environment are important conditions for forming chrysotile deposits. Three subtypes of chrysotile deposits could be formed in different tectonic settings and under different minerogenic geochemical conditions.
The Yadong‐Golmud Geoscience Transect in the Qinghai‐Tibet Plateau1
Authors: Gongjian Wu , Xuchang Xiao , Tingdong Li
Published: August 2010

Abstract On the basis of abundant geological and geophysical data, 6 terranes have been distinguished on the Qinghai‐Tibet Plateau. The plateau is a single integrated lithospheric unit although it is divided into blocks. With Amdo as a boundary, the crust may be divided into two parts with different crustal structures. The struc‐ture in the southern part is complex, while that in the northern part is simple, The current study has revealed that 8 factors such as slab subduction, overthrust and superimposition are responsible for crustal shortening and thickening in the region. The uplift of this region is possibly due to northward compression of the Indian plate and southward compression of the Eurasian plate with the former predominating. The compression led to the asthenospheric movements which were also influenced by thermal activity caused by doming at the boundary between the core and mantle.
Evolution of Apatites in the Diagenesis
Authors: Kuiwu Liu
Published: August 2010

Abstract Apatites occurring in sedimentary rocks are carbonate fluorapatites (C‐F apatites) with different CO2 contents. During diagenesis, the C2 in the C‐F apatites gradually decreased with the increasing strength of diagenesis, resulting in the systematic changes in refractive index, specific gravity, cell parameters and crystal chemistry of apatites. On the basis of X‐ray diffraction and IR spectroscopic analyses, the author proposes two parameters for determining diagenetic stages, i.e., the crystallinity index (CR) and sharpness index (SH). These two parameters serve as new criteria for the determination, which due to the common existence of phosphorous nodules and bands and argillo‐crystalline cement in sedimentary rocks, most likely have wide prospects for application.
The Coexisting Clinopyroxene‐Garnet Acidometer and Acidity Facies of Skarn Deposits
Authors: Wenwei Lin
Published: August 2010

Abstract On the basis of geological studies of skarn deposits in China and by using thermodynamic models of the solid solution, the coexisting clinopyroxene‐ garnet pair in skarn deposits has been analysed and a coexisting clinopyroxene‐garnet acidometer developed. They can be used to estimate the medium condition under which the skarn was formed. The research on the acidity for the formation of various metallic skarn deposits in China suggests that skarns endowed with dissimilar types of mineralization and occurring in diverse environments differ in the acidity conditions for their formation and in the trend of acidity variation of ore‐bearing fluid. This, coupled with the study of oxygen fugacity of coexisting minerals, makes it possible to establish the oxygen fugacity‐ acidity facies of skarn deposits, which reflect the close genetic relationship between the metallization and the formation of skarn.
Characteristics and Formation Mechanism of the Geothermal Field in the North China Downfaulted Basin
Authors: Moxiang Chen , Jiyang Wang , Ji' an Wang , Xiao Deng , Shuzhen Yang , Liangping Xiong , Juming Zhang
Published: August 2010

Abstract The geothermal field is mainly controlled by the regional tectonic framework characterized by alternations of uplifted and depressed basement, and exhibits a similar zoned distribution of temperatures. In the uplifted area the geothermal gradient (G) and terrestrial heat flow value(q) of the Cenozoic sedimentary cover are relatively high, with G = 3.5 − 5.0°C / 100 m and q = 63‐84 mW / m2; whereas in the depressions they are relatively low, with G = 2.7−3.5°C / 100 m and q = 46‐59 mW / m2. In the whole region, Ḡ = 3.581°C / 100 m and q = 61.5± 13.4 nW/ m2, indicating a comparatively high geothermal background and the presence of local geothermal anomalies. A comparison of the results of mathematical simulation of the geothermal field with the measured values shows a good agreement between them. The geothermal difference between various tectonic units is caused chiefly by the lateral and vertical variation of thermal properties of shallow crustal rocks. This phenomenon can be regarded as the result of redistribution of relatively uniform heat flows from the deep crust in the surficial part of the crust in the process of their upward conduction.