bluuebunny/crossref_metadata_2025 huggingface dataset:
Grounding Immigrant Generations in History: Cuban Americans and Their Transnational Ties
Authors: Eckstein Susan , Barberia Lorena
Published: August 2010

The two paradigms for analyzing immigrant experiences, “assimilationist” and “transnationalist,” leave unanalyzed important differences in immigrant adaptation rooted in different historical generational experiences. This article analyzes the importance of a historically grounded generational frame of analysis. It captures differences in views and involvements between two cohorts of first generation émigrés. Empirically, the study focuses on different Cuban-American cohort crossborder ties. The first cohort, comprised of émigrés who left between 1959 and 1979 primarily for political reasons, publicly oppose travel to Cuba because they believe it helps sustain a regime they wish to bring to heel. The second cohort, who emigrated largely for economic reasons, is enmeshed in transnational ties that, paradoxically, are unwittingly doing more to transform Cuba than first wave isolationism. The cohort comparison is based on interviews with émigrés in Union City, New Jersey and Miami, Florida. The analysis of effects of transnational ties rests on interviews in Cuba as well.
Host Societies and the Reception of Immigrants: Research Themes, Emerging Theories and Methodological Issues
Authors: Reitz Jeffrey G.
Published: August 2010

Research on the reception and integration of immigrants now recognizes more explicitly the impact that characteristics of societies have as they play host to immigrants. This brief introduction to six papers – by Kasinitz, Mollenkopf and Waters; Boyd; Model and Lin; Borjas; Martin; and Castles – shows how they reflect a research emphasis on four interrelated features of host societies: 1) pre-existing ethnic and race relations, 2) labor markets and related institutions, 3) government policies and programs both for immigration and for broader institutional regulation, and 4) the changing nature of international boundaries, part of the process of globalization. Cultural dimensions permeate analyses of each of these four aspects. Together with others in a larger collection of 18 papers developing this theme (scheduled for publication as a book by the Centre for Comparative Immigration Studies, University of California at San Diego), the various analyses suggest elements useful in constructing a theory of immigrant reception and incorporation taking proper account of the impact of host societies.
Educational Attainments of Immigrant Offspring: Success or Segmented Assimilation?
Authors: Boyd Monica
Published: August 2010

In this article, I study the educational attainments of the adult offspring of immigrants, analyzing data from the 1996 panel of the Survey of Labour and Income Dynamics (SLID). Fielded annually since 1993 by Statistics Canada, respondents are asked for the first time in 1996 to report the birthplaces of their parents, making it possible to define and study not only the foreign-born population (the first generation), but also the second generation (Canadian born to foreign-born parents) and the third-plus generation (Canadian born to Canadian-born parents). The survey also asked respondents to indicate if they are members of a visible minority group, thus permitting a limited assessment of whether or not color conditions educational achievements of immigrant offspring. I find that “1.5” and second generation adults, age 20–64 have more years of schooling and higher percentages completing high school compared with the third-plus generation. Contrary to the segmented “underclass” assimilation model found in the United States, adult visible minority immigrant offspring in Canada exceed the educational attainments of other not-visible-minority groups. Although the analysis is hampered by small sample numbers, the results point to country differences in historical and contemporary race relations, and call for additional national and cross-national research.
Migration and Community Formation under Conditions of Globalization
Authors: Castles Stephen
Published: August 2010

This article sets out to rethink the dynamics of the migratory process under conditions of globalization. Two main models of migration and incorporation dominated academic and policy approaches in the late twentieth century: first, the settler model, according to which immigrants gradually integrated into economic and social relations, re-united or formed families and eventually became assimilated into the host society (sometimes over two or three generations); second, the temporary migration model, according to which migrant workers stayed in the host country for a limited period, and maintained their affiliation with their country of origin. Globalization, defined as a proliferation of cross-border flows and transnational networks, has changed the context for migration. New technologies of communication and transport allow frequent and multi-directional flows of people, ideas and cultural symbols. The erosion of nation-state sovereignty and autonomy weakens systems of border-control and migrant assimilation. The result is the transformation of the material and cultural practices associated with migration and community formation, and the blurring of boundaries between different categories of migrants. These trends will be illustrated through case-studies of a number of Asian and European immigration countries. It is important to re-think our understanding of the migratory process, to understand new forms of mobility and incorporation, particularly the emergence of transnational communities, multiple identities and multi-layered citizenship.
Dancing across Borders: ‘Exotic Dancers,’ Trafficking, and Canadian Immigration Policy
Authors: Macklin Audrey
Published: August 2010

This article analyzes a Canadian immigration program that authorizes issuance of temporary work visas to ‘exotic dancers.’ In response to public criticism that the government was thereby implicated in the transnational trafficking of women into sexual exploitation, Citizenship and Immigration Canada retained the visa program de jure but eliminated it de facto. Using a legal and discursive analysis that focuses on the production of female labor migrants variously as workers, as criminals and as bearers of human rights, the article argues that the incoherence of Canadian policy can only be rendered intelligible when refracted through these different lenses. The article concludes by considering policy options available to the state in addressing the issue.
Conclusion: Theoretical Convergencies and Empirical Evidence in the Study of Immigrant Transnationalism
Authors: Portes Alejandro
Published: August 2010

Conclusions to books or journal issues commonly seek to summarize the preceding articles or chapters and offer some general guidelines about the relevant subject matter. This is a demanding but feasible task when the preceding material consists of empirical studies that lend themselves to an effort of synthesis. When the contents of the book or journal are, as in this case, themselves summaries of the literature and general reflections on the character of the field, the synthetic enterprises become far more demanding. It is difficult to agree with the conclusions and prescriptions of some authors without disagreeing with those of others. It is also unfair to take advantage of having the last word to comment critically on the arguments or recommendations advanced in the preceding articles.

The editors of this issue have ably summarized in their introduction the principal arguments presented in each article. It would be an unnecessary duplication to do so here. Instead, I propose to do the opposite of what is generally expected in a conclusion. That is, instead of presenting theoretical reflections on empirical materials, I intend to supplement the abundant theoretical arguments contained in this issue with a summary presentation of actual results. The latter come from the recently completed surveys of the Comparative Immigrant Entrepreneurship Project (CIEP). Before doing so, however, it would be useful to summarize some of the empirical and conceptual points on which the until-recently contentious literature on transnationalism has reached a measure of consensus. They represent indicators of progress, insofar as the weight of evidence and subsequent reflection on it have gradually led scholars from very different perspectives to agree on the tenability of certain arguments and the weakness of others.
Immigrants’ Language Skills: The Australian Experience in a Longitudinal Survey
Authors: Chiswick Barry R. , Lee Yew Liang , Miller Paul W.
Published: August 2010

This article is concerned with the determinants of English language proficiency (speaking, reading and writing) among immigrants. It presents a model of immigrant destination language proficiency based on economic incentives, exposure to the destination language, and efficiency in second language acquisition. A unique data set, the Longitudinal Survey of Immigrants to Australia, is used to test the model. This survey had three waves, at about six months, eighteen months and three-and-a-half years after immigration. The analyses are performed by wave, type of language skill and gender using probit analysis. Bivariate probit analysis is used across waves. The hypotheses are supported by the data. The bivariate probit analysis indicates a positive correlation in the unexplained component that declines with time between waves, suggesting a “regression to the mean” in the unobserved components of English language proficiency.
The Grassroots Reconfiguration of U.S. Immigration Policy
Authors: Wells Miriam J.
Published: August 2010

Despite the increasing constriction of immigrants’ rights at the federal level, local responses have been much more varied, countering, compensating for, even transforming policies originating from the national core. This article attributes this divergence in part to the multi-layered, ambiguous, and contradictory structure of the U.S. nation-state in the context of a transnational economy and society. It shows how three facets of state structural complexity – its multiple levels, diverse administrative branches, and decentralized agencies – have created openings for local actors, deploying normative arguments as to the issues at stake, to reshape the outcomes of U.S. immigration policy on the ground.
Institutionalizing Recent Rural Emigration from China to Europe: New Transnational Villages in Fujian
Authors: Thunø Mette , Pieke Frank N.
Published: August 2010

The prevalence of irregular migration from a small region in the central parts of Fujian province has associated Chinese emigration with organized crime, exploitation and opportunism in a range of popular and academic writings both in China and outside China. Although migration brokers (“snakeheads”) play an important role in maintaining migratory flows already underway, they should not be seen as the root cause of migration from Fujian. In this article, we report on recently conducted fieldwork in two villages in central Fujian characterized by large-scale emigration to Europe. Emigration from this part of China is strongly embedded in local political, sociocultural and economic institutions and histories. Migration brokers are certainly a part, but not more than that, of these local institutions. We conclude that the local embeddedness of migration renders population mobility from each area in China highly specific, and broad generalizations on the causes, nature and direction of the totality of Chinese, or even Fujianese, migration are bound to misrepresent a highly complex reality.
Quantification of Cyclobutane Pyrimidine Dimers Induced by UVB Radiation in Conidia of the Fungi Aspergillus fumigatus, Aspergillus nidulans, Metarhizium acridum and Metarhizium robertsii
Authors: Nascimento Érika , Da Silva Sergio H. , Dos Reis Marques Everaldo , Roberts Donald W. , Braga Gilberto U. L.
Published: August 2010

Conidia are responsible for reproduction, dispersal, environmental persistence and host infection of many fungal species. One of the main environmental factors that can kill and/or damage conidia is solar UV radiation. Cyclobutane pyrimidine dimers (CPD) are the major DNA photoproducts induced by UVB. We examined the conidial germination kinetics and the occurrence of CPD in DNA of conidia exposed to different doses of UVB radiation. Conidia of Aspergillus fumigatus, Aspergillus nidulans and Metarhizium acridum were exposed to UVB doses of 0.9, 1.8, 3.6 and 5.4 kJ m−2. CPD were quantified using T4 endonuclease V and alkaline agarose gel electrophoresis. Most of the doses were sublethal for all three species. Exposures to UVB delayed conidial germination and the delays were directly related both to UVB doses and CPD frequencies. The frequencies of dimers also were linear and directly proportional to the UVB doses, but the CPD yields differed among species. We also evaluated the impact of conidial pigmentation on germination and CPD induction on Metarhizium robertsii. The frequency of dimers in an albino mutant was approximately 10 times higher than of its green wild‐type parent strain after exposure to a sublethal dose (1.8 kJ m−2) of UVB radiation.
The Effect of Actinoquinol with Hyaluronic Acid in Eye Drops on the Optical Properties and Oxidative Damage of the Rabbit Cornea Irradiated with UVB Rays
Authors: Čejka Čestmír , Luyckx Jacques , Ardan Taras , Pláteník Jan , Širc Jakub , Michálek Jiří , Čejková Jitka
Published: August 2010

Irradiation of the cornea with UVB rays leads to its oxidative damage, swelling and increased light absorption. We investigated changes in the corneal optics (evaluated by changes of corneal hydration and light absorption) and microscopical disturbances of corneas irradiated with UVB rays as influenced by eye drops containing actinoquinol with hyaluronic acid. Rabbit corneas were irradiated with a daily dose of 0.5 or 1.01 J cm−2 of UVB rays (312 nm) for 4 days. During irradiation, the eye drops were applied on the right eye and buffered saline (or hyaluronic acid) on the left eye. On day 5 the rabbits were sacrificed and the corneas examined spectrophotometrically for light absorption. The corneal thickness (hydration) was measured using a pachymeter. Corneas of some other rabbits were examined immunohistochemically. After buffered saline treatment UVB rays evoked changes in the corneal optics and induced oxidative damage of the corneas. After actinoquinol‐hyaluronic acid application, these changes were diminished. Hyaluronic acid alone was less effective. In conclusion, actinoquinol‐hyaluronic acid eye drops decreased changes in corneal optics and suppressed oxidative damage in the UVB‐irradiated cornea. However, the effective corneal protection by these eye drops was limited to the lower UVB dose.
Protective effects of HGF‐MSP chimer (metron factor‐1) on liver ischemia‐reperfusion injury in rat model
Authors: XUE Feng , ZHANG Jian Jun , XU Long Mei , ZHANG Cheng , XIA Qiang
Published: August 2010

OBJECTIVE:  It has been reported that metron factor‐1 (MF‐1), an engineered chimerical factor containing selected functional domains of hepatocyte growth factor and macrophage‐stimulating protein (HGF–MSP), could prevent apoptosis and have an anti‐inflammatory effect. In this study, we investigate the protective effect of MF‐1 on liver ischemia‐reperfusion (I/R) injury.

METHODS:  Overall 30 Sprague Dawley rats were randomly divided into three groups: the I/R model group (n = 12), the MF‐1 treatment group (n = 12), and the sham‐operated group (n = 6). Liver I/R injury was induced by clamping the blood supply to the left and median lobes of liver by an atraumatic clamp for 90 min, then removing the clamp and allowing reperfusion. Blood samples were obtained on days 1, 2, 3 and 7 to assess liver biochemistry and the histology of liver tissue. Levels of malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO), endothelial nitric oxide synthase and inducible nitric oxide synthase were measured. In addition, the anti‐oxidative effect of MF‐1 on hepatocytes was assessed in vitro.

RESULTS:  MF‐1 treatment improved the rat survival rate significantly (P < 0.05). Liver biochemistry and histological changes were significantly ameliorated. MDA increased and SOD and NO decreased in the liver tissue. In vitro, MF‐1 protected the human hepatic cell line HL‐7702 from damage of oxidative stress.

CONCLUSION:  MF‐1 could protect the liver from I/R injury, which might involve the reduction of oxygen free radicals and the increase of NO synthesis in an injured liver.
Carboniferous Biostratigraphy of Guizhou Province
Authors: Qianghe Wu
Published: August 2010

Abstract The Carboniferous in Guizhou may be divided into 3 lithostratigraphic regions, 2 series and 7 stages. The Lower Carboniferous is composed of 4 regional stages, 1 foraminifer assemblage, 4 fossil coral zones (with 9 subzones) and 11 brachiopod assemblages; the Upper Carboniferous is divided into 3 regional stages, 9 fusulinid zones (with 2 subzones) and 4 ammonite zones. Based on the studies of foraminifers and conodonts, the base of the Carboniferous in Guizhou is placed at least near the top of the coral Cystophrentis zone.
Isotope Geological Studies of Granite‐Type Uranium Deposits in South China
Authors: Weizhou Shen , Zuhuan Zhang , Bangtong Zheng
Published: August 2010

Abstract The uranium‐bearing granites in South China can be classified into two types, namely, syntectic type and transformation type. A fairly systematic hydrogen, oxygen, carbon, sulfur isotopic study of uranium deposits related to these two types of granites has been carried out by the authors, and the results show that they have obvious differences in such aspects as ore‐forming and rock‐forming ages, properties of ore‐forming solutions and source of ore‐forming substances. The authors hold that the uranium deposits related to the syntectic type granitoids are intimately connected with magmatism in time and space, whereas the uranium deposits related to the transformation type granites, though spatially linked up with uranium‐bearing granites, should actually owe their formation to extension in the fault block movement in South China.
Terminal Precambrian Palaeogeographic Framework of China1
Authors: Xiufu Qiao , Lifang Ma , Huimin Zhang
Published: August 2010

Abstract The original locations and relationships of four plates within the mainland of China from 800 to 600 Ma during the terminal Precambrian were reconstructed based on the palaeomagnetic and geological data. The Tarim, Yangtze and Cathaysian plates were once linked (in 800‐700 Ma) and located in the same low‐latitude zone of the northern hemisphere. But later, in 700‐600 Ma, the Tarim plate was separated from the Yangtze‐Cathaysian plate. The Sino‐Korean plate was always far away from the Yangtze plate, both being separated by oceanic crust, and lay in the high‐latitude zone of the northern hemisphere.

The above‐mentioned palaeogeographic framework directly led to complete differences in respect to distribution of low‐ latitude glaciation, sedimentary facies, palaeoclimate, palaeobiogeography and stratigraphic sections between the North and South China domains during the terminal Precambrian.
Apparent Polar Wander Path from the Tarim Block in China
Authors: Yanping Li , Sharps Robert , McWilliams Michael , Zhengkun Zhang , Yong' an Li , Qiang Li , Tongjian Zhai , Zhenjia Gao
Published: August 2010

Abstract The apparent polar wander (APW) path from the Tarim block consists of palaeo‐ magnetic poles of Devonian (λ = 16 ° N, φ= 165 ° E, A95 = 4 °), Late Carboniferous (A = 41 ° N, φ= 160 ° E, A95 = 4 °), Permian u = 61 ° N, φ=177° E, A95 = 9°), Early Triassic U = 69° N, φ=183° E, A95=ll °) and Jurassic/ Cretaceous (A = 65 ° N, (A = 214 ° E, A95 = 6 °) times. On the basis of this APW path, it is concluded that the Tarim block was subducted beneath the Kazakstan plate between Devonian and Permian times. The Tarim, North China and South China blocks were sutured between the Early Triassic and Early Cretaceous. Tarim had moved eastward some 2000 km relative to Siberia since the Cretaceous.
Himalayan Tectonic Evolution in the East Asian Peri‐Pacific Region
Authors: Shengqin Cui , Jinrong Li
Published: August 2010

Abstract This paper summarizes the Late Palaeozoic, Indosinian and Yanshanian palaeotectonic settings in the peri‐Pacific region of East Asia. On that basis, the Himalayan crustal movement in the region is divided into the early and late tectonic stages and two principal tectonic phases. From the ocean to the continent, 5 gigantic Himalayan formation‐ deformation belts are distinguished; they are the Northwest Pacific trench‐ island arc belt, the Northwest Pacific marginal sea basin belt, the East China Sea‐ northern South China Sea continental‐shelf down‐faulted belt, the East Asian epicontinental rift belt, and the East Asian intracontinental rift belt. The Early and Late Himalayan tectonic evolution is dealt with. Finally the state of the Himalayan regional stress field and its evoution in the region are discussed. It is considered that the mechanism of their formation is closely related to the continent‐ocean and surface‐deep earth interaction.
Analytical Model for the Palaeoenvironmental Evolution of the Nihewan Beds
Authors: Jun Yue , Qizhong Wen
Published: August 2010

Abstract In this paper, the evolutional characteristics of palaeoclimate and oxidation‐reduction conditions as well as acidity‐alkalinity environment are discussed by means of the step‐regression, cluster, optimal partitioning and correlation analyses of CaCO3, C / P2O5, Fe2+ / Fe3+, pH and Eh values, taking the Xiaodukou section in the Nihewan basin as an example. The CaCO3, C / P2O5 and pH were calculated respectively using the optimal partitioning method. Thus five cold zones and six warm zones as well as five reduction and six oxidation zones were distinguished. Then the inductive method was used to produce four numerical groups: 8.10, 8.3–8.4, 8.6–8.7 and 8.9–8.97. The above‐mentioned results are respectively based on CaCO3 content, C/ P2O5 and pH values. From Fig. 3, Tables 1 and 2 it can be seen that the Nihewan Beds were formed mainly under a reduction and slightly alkaline environment of cold climate, with pH values of 8.3–8.4. Fig. 3 shows that bed 35 is approximately near the boundary between the Brunhes and Matuyama polarity epochs, 0.73 Ma in age; bed 26 is roughly near the Jaramillo event (base), 0.97 Ma in age; bed 18 coincides roughly with the magnetostratigraphic boundary of 2.00 Ma (?). Bed 13 may be the Pleistocene‐Pliocene boundary, 2.48 Ma in age. Thus geochemical zones I, ?, IH and IV include respectively cold zones 1; 2 and 3; 4; and 5.
Palaeomagnetic Study on the Precambrian‐Cambrian Boundary Candidate Stratotype Section at Meishucun, Yunnan
Authors: Qizhong Liang , Wu Fang , Voo Rob Van der
Published: August 2010

Abstract The Meishucun secton has been recommended as an international candidate stratotype secton of the Precambrian‐Cambrian boundary. The paper deals with the palaeomagnetic study on the section. A total of 159 palaeomagnetic samples were successively collected from the platform‐facies sequence of carbonates and phosphates at the section. Thermal demagnetization results indicate a great majority of the rocks at the section have been strongly overprinted by recent magnetic field, but 57 samples have preserved remanent magnetization with antipodal directions (mean D /1 = 4.2 ° / 7.1 °, K= 9, α95= 6.6 ° ). Baaed on calculation, the location of the palaeomagnetic pole was at 68.8 ° N and 270.7 ° E, which is different from any palaeopoles obtained from younger Phanerozoic rocks in South China. The results reveal a polarity zonation which includes at least 9 reversal events. A comparison of China' s magnetostratigraphic records with those from Siberia, Australia and the western U.S.A. shows that all the sections are characterized by frequent polarity reversals'.
Origin, Evolution and Mechanism of the Jehol Fauna
Authors: Si'en Wang
Published: August 2010

Abstract This paper deals with the geographic distribution and geological setting of the Jehol (northeast Hebei‐southwest Liaoning‐southeast Inner Mongolia) fauna, and discusses the origination and the evolution of its major biological groups. It is demonstrated that the Yan‐Liao (northern Hebei‐western Liaoning) area is the provenance for the fauna. Why the fauna originated and developed in the area was intimately related to such factors as the palaeoclimate, palaeogeography, crustal movement, volcanism and frequent reversals of magnetic polarity at that time, in addition to the internal factors of the organisms themselves.
Tertiary Calcareous Nannofossil Biostratigraphy in the North Part of the South China Sea
Authors: Weiwu Duan , Yongyang Huang
Published: August 2010

Abstract The marine Tertiary sequence in the north part of the South China Sea may be divided into 18 Late Oligocene to Pliocene calcareous nannofossil zones and one unnamed Eocene assemblage based on an analysis of calcareous nannofossils from 40 offshore boreholes. The unnamed Eocene assemblage has been found only on the northeast margin of the Zhujiangkou basin. The 18 cakareous nannofossil zones of the Late Oligocene to Pliocene were deposited in succession, but their development degrees are different. Among the 18 calcareous nannofossil zones, those corresponding to Martini's (1971) NN4‐NN5 zones, NN11 zone and NN13‐NN15 zones are well developed, relatively persistent laterally and also widely distributed. They are the important markers for the stratigraphical subdivision and correlation of the Upper Tertiary between the various basins in the north part of the South China Sea. Based on the calcareous nannofossils and the sedimentsry features coup‐led with the foraminifer zonation in certain basins, the present paper discusses the sedimentary characteristics of the marine Tertiary and as well as the distribution and development of the sedimentary hiatus in the region. The calcareous nannofossil markers for the Upper / Lower Tertiary and the Quaternary / Tertiary boundaries, and the characteristics and geological significance of the reworked calcareous nannofossils are also discussed in the paper.
Quartz‐Ferberite Oxygen Isotope Geothermometer and Its Geological Applications
Authors: Tiping Ding , Yushan Liu , Defang Wan , Zhijian Liu , Jincheng Li , Guilan Zhang
Published: August 2010

Abstract Experiments for oxygen isotope exchange between ferberite and water were carried out and the following equation on oxygen isotope fractionation between ferberite and water against temperature was obtained: 10001nα FeWO4 −H2O = 1.04 × 106T −2 − 2.5

Combining this equation with the equation of Clayton et al. (1972) on oxygen isotope fractionation between quartz and water, an equation on oxygen isotope fractionation between quartz and ferberite was obtained: 10001nαSiO2 − FeWO4 = 2.34 × 106T−2 − 0.4

The Bigeleison‐Mayer function method was used to calculate the oxygen isotope fractionation between quartz and ferberite. The theoretical curve obtained agrees with the experimental calibration results quite well in the temperature range of study.

The above calibrated equation has been used in 5 world famous tungsten deposits to determine their temperatures of formation. The results show that the temperature range for an idividual deposit determined by this geothermometer agrees with those obtained from fluid inclusion determination and other isotope geothermometers.
Graptolite, Chitinozoan and Scolecodont Reflectances and Their Use as Indicators of Thermal Maturity
Authors: Xiaofeng Wang , Hoffknecht Andreas , Jianxin Xiao , Shangqing Chen , Zhihong Li , Bainer Brocke Rainer , Erdtmann Bernd‐D.
Published: August 2010

Abstract Based on studies of the reflectance of Ordovician and Silurian zooclasts from 11 sections around the Huangling Anticline, Hubei, China, combined with determination of the conodont colour alteration indices (CAI) and of infrared spectroscopy of dispersed organic matter from the same or adjacent horizons, it is further proved that reflectances of graptolites, chitinozoans and scolecldonts, like vitrinite and natural bitumen, increase with increasing maturation, but follow different reflectance paths. They may be used, therefore, as thermal maturation indicators. Graptolites display optically strong anisotropy. The maximum reflectance measured from graptolite on polished section cut parallel to the bedding plane is the most suitable for determination of maturation of their host rocks. In polished section chitinozoan and scolecodont show reflectance, but no bireflectance owing to their isotropy. The random reflectance of chitinozoans is higher than that of scolecodonts in the case of the same maturity. By analysing the distribution trends of graptolite, chitionzoan and scolecodont reflectances, the Ordovician and Silurian strata can be subdivided into three areas of maturation in the present region. The potential of oil or gas generation is discussed for each area. The result is basically coincident with the distribution pattern of regional organic maturation presented by CAI and infrared spectroscopic determination of organic matter.
Seawater Intrusion in the Longkou Laizhou Area, Shandong1
Authors: Yuqun Xue , Chunhong Xie , Jichun Wu , Peimin Liu , Jianji Wang , Qingbo Jiang , Hongwen Shi , Pihai Ning
Published: August 2010

Abstract The extensive intrusion (covering an area of 83.7‐238.3 km2 and accounting for 18.6‐31.5% of the total area of the plain), the presence of a transitional zone 1.5‐6.0 km in width, and the interconnection in distribution between the seawater intrusion district and the region lower than the sea level caused by the strong drop of the groundwater level are major characteristics of the seawater intrusion in the study area. Cation exchange played an important role during the formation of chemical composition of the groundwater in the seawater intrusion district.
Metamorphism of the Bikou Group in the Shanxi‐Gausu‐Sichuan Border Region1
Authors: Chunjing Wei
Published: August 2010

Abstract The Bikou Group on the Shaanxi‐Gansu‐Sichuan border is composed of Mid‐Late Proterozoic metamorphosed bimodal volcanic rocks and flysch sediments. Its metamorphism may be divided into the blueschist and greenschist facies. Three metamorphic zones, i.e. zones A, B, and C, may be distinguished on the basis of the field distribution of metamorphic rocks and the variation of b0 values of muscovite. Blueschists are characterized by coexistence of sodic amphiboles and epidote and occur as stripes or relict patches in extensive greenschists of zone A. Studies of metamorphic minerals such as amphiboles, chlorite, epidote and muscovite and their textural relationships indicate that blueschists and greenschists were not formed under the same metamorphic physico‐chemical conditions. The blueschist facies was formed at temperatures of 300‐400°C and pressures of 0.5–0.6 GPa. The greenschist facies in zones A and B has similar temperatures but its pressure is only 0.4 GPa or so. The transition from the blueschist to greenschist facies is a nearly isothermal uplift process. The rock and mineral assemblages of the Bikou Group indicate that the blueschist facies metamorphism of the group might be related to crustal thickening or A‐subduction accompanying the closure of an intracontinental small ocean basin.
A Study of the Rhenium‐Osmium Geochronometry of Molybdenites1
Authors: Andao Du , Hongliao He , Ningwan Yin , Xiaoqiu Zou , Yali Sun , Dezhong Sun , Shaozhen Chen , Wenjun Qu
Published: August 2010

Abstract This study deals with the first application of the isotope dilution‐inductively coupled plasma mass spectrometry in the rhenium‐osmium geochronometry in China. The chemical separation procedure included decomposition of samples by means of alkali fusion, extraction of rhenium by acetone and extraction of osmium by distillation. The recovery of both elements in the entire process was more than 90% . The blanks of analyses were 0.07 ng for rhenium and 0.01 ng for 187Os. The mineralization ages of molybdenites from four molybdenum deposits in China were determined by using this method, with a precision (2σ) of about ±3% . These results agree satisfactorily with their geological backgrounds. The Re‐Os method can directly determine ages of metal deposits and reflect the true ages more reliably than other dating methods that only determine the ages of country rocks from which mineralization ages are inferred. As many hydrothermal sulphide deposits usually contain molybdenites, this method has bright prospects of wide application.
Evolution of the Extensional Rifted Yunnan‐Guizhou‐Guangxi Oceanic Basin During the Late Hercynian to Middle Indosinian Stage
Authors: Wenchen Xia , Jie Zhou , Jianxi Lei , Nianmao Zhang , Yang Peng
Published: August 2010

Abstract On the basis of exhaustive researches on the facies sequences and depositional evolutionary process of various depositional systems, the genetic stratigraphic framework of the extensional rifted oceanic basin, which has undergone strong structural destruction, has been reconstructed by means of dynamic genetic stratigraphic analysis. Five depositional episodes have been distinguished from various isochronous stratigraphic boundaries and stratigraphic sequences with the three‐dimensional structure of each depositional episode analysed in detail. The tectonic paleogeographic environment corresponding to different stages of each depositional episode has been reconstructed for individual depositional system tracts. And the evolution history of this rifted basin has been divided into four stages: initial rifting and oceanization of continental crust, stretching and spreading of the basin, subduction and basin differentiation, and convergence and collision. A NNE‐trending intracontinental soft collision suture was left after the closing of the basin.
Discovery of Cosmic Dust in Gold Deposits in Northwestern Sichuan and Its Significance
Authors: Minghua Zheng , Yufeng Zhou , Renping Fu
Published: August 2010

Abstract In recent years, a considerable amount of microscopic spherules have been found in concentrates recovered from some stratabound gold deposits occurring in Middle‐Upper Triassic turbidite series in northwestern Sichuan. Study indicates that these spherules are cosmic dust. It is the first time that cosmic dust of extraterrestrial origin has been found in hydrothermal gold deposits in China.

The spherules are steel‐grey in colour and show metallic luster. Their grain size is commonly less than 100 μm. According to their composition, they belong to chromium ‐ rich iron cosmic dust. The spherules have complex and diverse microscopic structures and textures, i.e. they show a very distinct Widmanstāten structure.

The variation of cosmic dust content in gold deposits exhibits a positive correlation with the mineralization intensities and hydrothermal alteration. Such a relation indicates that the ore substances may transport not only mechanically but also may chemically in hydrothermal solutions.
Petrogenesis and Geochemistry of Neogene Basalts in Eastern Anhui
Authors: Xiachen Zhi , Daogong Chen , Jin Yang
Published: August 2010

Abstract The basalt terrain of the Neogene Huangguoshan and Guiwu Formations of eastern Anhui on the east side of the Tancheng ‐ Lujiang fault belt is one of a few Cenozoic basalt terrains in eastern China for which detailed geochemical study has not been conducted. This paper reports the abundances of major elements and more than 20 trace elements (including REE) of 22 samples and the Nd, Sr and Pb isotopic compositions of 11 samples from the eastern Anhui basalt terrain, thus more or less systematically revealing the geochemical characteristics of this continental basalt suite. The paper discusses the origin of the basalt suite and the character and process of its mantle source. The basalt suite was derived from a heterogeneous continental lithospheric mantle with end members characteristic of the EMI‐type oceanic basalt mantle, which was affected by mantle metasomatism (or enrichment of trace elements) and was characterized by a multi‐stage evolution under open conditions.
MODELING FOREST PRODUCTIVITY ACROSS LARGE AREAS AND LONG PERIODS
Authors: LANDSBERG JOE , COOPS NICHOLAS C.
Published: August 2010

ABSTRACT. There are three classes of forest model used to simulate forest productivity across large areas and over long periods: growth and yield models, based on statistical relationships derived from measurements on trees; the so‐called gap models, concerned with species succession and dynamics, and carbon balance or biomass models. The characteristics of each type are discussed and illustrated by reference to some of the more important of the models in current use. The emphasis in this paper is on the carbon balance models, particularly on a new model (3‐PG), developed in a deliberate attempt to bridge the gap between growth and yield and carbon balance models, and the companion model (3‐PGS) derived from 3‐PG to utilize satellite data as inputs to constrain the simulation calculations and improve estimates of growth over time. 3‐PG/3‐PGS run on monthly time steps, driven by weather data, and avoid the problems of over‐parameterization and the requirements for a great deal of input data that limit the practical value of most carbon balance models. We present test results from 3‐PG against experimental data, and against forest plot (mensuration) data from large areas; also test results from 3‐PGS against estimates of average forest growth over large areas, and in plantations with different planting times, using AVHRR and Landsat MSS data to constrain the model outputs. The paper discusses the problems of the variability of natural forests and the difficulties this causes in validating models intended for use over large areas. The value of remote sensing as means of overcoming this problem is considered.
EXPLOITATION OF AN UNMANAGED LOCAL COMMON. ON THE PROBLEMS OF OVERGRAZING, REGULATION AND DISTRIBUTION
Authors: SKONHOFT ANDERS
Published: August 2010

ABSTRACT. A system comprising grazing land and livestock is considered. The livestock is privately owned while the grazing land is communally owned. A model is formulated to analyze the utilization of this system, assuming that the pastoralists maximize the size of their livestock herd, subject to a minimum amount of income. This exploitation scheme is compared with the outcome of the standard neoclassical model where the resource rent is maximized. It is demonstrated that it is an open question as to which of these two models leads to the highest grazing pressure. However, as different economic and social mechanisms are working in the direction of economic overgrazing, the policy implications are quite different when it comes to managing and regulating grazing pressure.
MODELING THE SPATIAL DISTRIBUTION OF THE ECONOMIC COSTS AND BENEFITS OF ILLEGAL GAME MEAT HUNTING IN THE SERENGETI
Authors: HOFER HERIBERT , CAMPBELL KENNETH L.I. , EAST MARION L. , HUISH SALLY A.
Published: August 2010

ABSTRACT. Illegal game meat hunting in the Serengeti National Park, Tanzania, and adjacent game reserves provides an important source of protein and cash income to local communities. We construct a profitability model that describes the spatial distribution of the economic costs and benefits of illegal hunting in the Serengeti during the late 1980s and early 1990s. Costs included capital investment in hunting weapons, WR, and the opportunity cost of hunting, WO, both held to be constants; and two spatially variable components, the logistic effort of traveling to hunting areas, WL, and the penalties incurred if arrested, WP. Benefit was the expected income from the sale of meat from resident wildlife species. The model suggests: (1) WR is the most important cost. (2) WL is the second most important cost and likely to determine the spatial distribution of hunting activity if hunters seekto minimize costs. (3) WO and WP are of minor importance, the former because alternative sources of income provide low pay, the latter because the overall chance of being arrested is low. (4) WP exceeds WL only in areas close to the boundary of protected areas. (5) Although resident wildlife contributes only a minor share of illegal offtake compared to the migratory herds, hunting resident wildlife is profitable in 68% of the area. This suggests that hunting of resident and migratory wildlife is highly profitable and may explain why the utilization of the target populations has become increasingly unsustainable.
THE EFFECTS OF ITQ IMPLEMENTATION: A DYNAMIC APPROACH
Authors: ANDERSON LEE G.
Published: August 2010

ABSTRACT. This paper investigates the intertemporal effects of introducing Individual Transferable Quota, ITQ, fishery management programs on stock size, fleet size and composition, and returns to quota holders and to vessel operators. Theoretical analysis is conducted using a specific version of a general dynamic model of a regulated fishery. It is demonstrated that the effects will differ depending upon the prevailing regulation program, current stock size, and existing fleet size, composition and mobility and upon how the stock and fleet change over time after the switch to ITQs. The paper expands upon previous works by modeling the dynamics of change in fleet and stock size and by allowing for changes in the TAC as stock size changes, by comparing ITQs to different regulations, and by allowing the status quo before ITQ implementation to be something other than a bioeconomic equilibrium. Specific cases are analyzed using a simulation model. The analysis shows that the annual return per unit harvest to quota owners can increase or decrease over the transition period due to counteracting effects of changes in stock and fleet size. With ITQs denominated as a percentage of the TAC, the current annual value of a quota share depends upon the annual return per unit of harvest and the annual amount of harvest rights. Because the per unit value can increase or decrease over time, it is also possible that the total value can do the same. Distribution effects are also studied and it is shown that while the gains from quota share received are the present value of a potentially infinite stream of returns, potential losses are the present value of a finite stream, the length of which depends upon the remaining life of the vessel and the expected time it will continue to operate.
CONSTANT EFFORT AND CONSTANT QUOTAFISHING POLICIES WITH CUT‐OFFS IN A RANDOM ENVIRONMENT
Authors: BRAUMANN CARLOS A.
Published: August 2010

ABSTRACT. Consider a population subjected to constant effort or constant quota fishing with a generaldensity‐dependence population growth function (because that function is poorly known). Consider environmental random fluctuations that either affect an intrinsic growth parameter or birth/death rates, thus resulting in two stochastic differential equations models. From previous results of ours, we obtain conditions for non‐extinction and for existence of a population size stationary density. Constant quota (which always leads to extinction in random environments) and constant effort policies are studied; they are hard to implement for extreme population sizes. Introducing cut‐offs circumvents these drawbacks. In a deterministic environment, for a wide range of values, cutting‐off does not affect the steady‐state yield. This is not so in a random environment and we will give expressions showing how steady‐state average yield and population size distribution vary as functions of cut‐off choices. We illustrate these general results with function plots for the particular case of logistic growth.
FIRE DISTURBANCE PATTERNS AND FOREST AGE STRUCTURE
Authors: LI CHAO , BARCLAY HUGH J.
Published: August 2010

ABSTRACT. This paper investigates how the stability of forest age‐distribution is related to the fire regimes. We start with the derivation of theoreticalnegative exponentialforest age‐distribution, and use three models to explore the condition with which a stable age‐distribution could be expected. The results suggested that a stable age‐distribution could always be achieved as long as the forest age‐specific mortality is constant over time, and the shape of a stable age‐distribution is mainly determined by the forest age‐specific mortality. However, the stability of forest age‐distribution will be reduced when a small variation in the age‐specific mortality is introduced. The simulation results of the possible patterns of the age‐distribution under various fire regimes indicated that a variety of age‐distribution curves could appear, including negative exponential and one or multiple peaks in the curves. The results suggested that a stable forest age‐distribution might never be achieved if the forest landscape is subjected to large and irregular fire disturbances.
A MODEL OF TROPICAL MARINE RESERVE‐FISHERY LINKAGES
Authors: RODWELL LYNDA D. , BARBIER EDWARD B. , ROBERTS CALLUM M. , McCLANAHAN TIM R.
Published: August 2010

ABSTRACT. The excessive and unsustainable exploitation of our marine resources has led to the promotion of marine reserves as a fisheries management tool. Marine reserves, areas in which fishing is restricted or prohibited, can offer opportunities for the recovery of exploited stock and fishery enhancement. In this paper we examine the contribution of fully protected tropical marine reserves to fishery enhancement by modeling marine reserve‐fishery linkages. The consequences of reserve establishment on the long‐run equilibrium fish biomass and fishery catch levels are evaluated. In contrast to earlier models this study highlights the roles of both adult (and juvenile) fish migration and larval dispersal between the reserve and fishing grounds by employing a spawner‐recruit model. Uniform larval dispersal, uniform larval retention and complete larval retention combined with zero, moderate and high fish migration scenarios are analyzed in turn. The numerical simulations are based on Mombasa Marine National Park, Kenya, a fully protected coral reef marine reserve comprising approximately 30% of former fishing grounds. Simulation results suggest that the establishment of a fully protected marine reserve will always lead to an increase in total fish biomass. If the fishery is moderately to heavily exploited, total fishery catch will be greater with the reserve in all scenarios of fish and larval movement. If the fishery faces low levels of exploitation, catches can be optimized without a reserve but with controlled fishing effort. With high fish migration from the reserve, catches are optimized with the reserve. The optimal area of the marine reserve depends on the exploitation rate in the neighboring fishing grounds. For example, if exploitation is maintained at 40%, the ‘optimal’ reserve size would be 10%. If the rate increases to 50%, then the reserve needs to be 30% of the management area in order to maximize catches. However, even in lower exploitation fisheries (below 40%), a small reserve (up to 20%) provides significantly higher gains in fish biomass than losses in catch. Marine reserves are a valuable fisheries management tool. To achieve maximum fishery benefits they should be complemented by fishing effort controls.
MANAGING ECOLOGICALLY INTERDEPENDENT SPECIES
Authors: BULTE ERWIN H. , DAMANIA RICHARD
Published: August 2010

ABSTRACT. We analyze open access harvesting of a predator species, while allowing for ecological interaction with herbivore species (the prey). In contrast to existing studies, we find that under some conditions open access harvesting may contribute to the abundance of predator and prey species. Particularly in fragmented habitats, moderate harvesting intensity may be a low‐cost substitute for management, and measures to reduce harvesting may result in collapse of predator and prey stock. These results highlight the importance of analyzing the ecological underpinnings of systems when manipulating economic parameters to promote conservation.