bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on Temporal and Spatial Variations of Phytoplankton in Lake Chaohu
Authors: Deng Dao‐Gui , Xie Ping , Zhou Qiong , Yang Hua , Guo Long‐Gen 
Published: April 2007

AbstractTemporal and spatial variations of the phytoplankton assemblage in Lake Chaohu, a large shallow eutrophic lake in China, were studied from September 2002 to August 2003. A total of 191 phytoplankton species was identified, among which Chlorophytes (101) ranked the first, followed by Cyanophytes (46) and Bacillariophytes (28). On average over the entire lake, the maximum total algal biomass appeared in June (19.70 mg/L) with a minimum (5.05 mg/ L) in November. In terms of annual mean biomass, cyanobacteria contributed 45.43% to total algal biomass, followed by Chlorophytes (27.14%), and Bacillariophytes (20.6%). When nitrate (NO3‐N) and ammonium (NH4‐N) concentrations dropped in spring, fixing‐nitrogen cyanobacterium (Anabaena) developed quickly and ranked the first in terms of biomass in summer. It is likely that dominance of zooplanktivorous fish and small crustacean zooplankton favored the development of the inedible filamentous or colony forming cyanobacteria. The persistent dominance of cyanobacteria throughout all seasons may indicate a new tendency of the response of phytoplankton to eutrophication in Lake Chaohu.
Leaflet Movement of Robinia pseudoacacia in Response to a Changing Light Environment
Authors: Liu Cheng‐Cheng , Welham Clive V. J. , Zhang Xian‐Qiang , Wang Ren‐Qing 
Published: April 2007

AbstractDiurnal and nocturnal leaflet movement of black locust (Robinia pseudoacacia L.) was investigated under three light schemes: 100% natural irradiance, 50% shading, and 90% shading. Changes in leaf mid‐vein angle were described by measurements of two planes: (i) β, the angle formed by the bottom of the petiolule and its relation to the horizontal plane; and (ii) θ, the angle between the petiolule and the main leaflet vein. The two highest light regimens had a significant effect on β. Variation in β tends to make the leaflet more erect, thereby minimizing any negative impact of high irradiance on leaf lamina. Light‐dark rhythms induced variation in θ (termed nyctinastic movement). Nyctinastic movement is important during the low light levels experienced by leaflets in early morning and late afternoon. At low light levels, the leaflet stopped nyctinastic movement and θ was fixed at an angle that may have enabled the leaf lamina to maximize light interception. After the light‐dark cycle was reestablished, nyctinastic movement was restored. Taken together, our results suggest that irradiance induces variation in β leading to diurnal leaflet movement (diaheliotropism), whereas the light‐dark cycle influences θ, which results in nocturnal leaflet movement. Both angles are important for describing patterns of leaf movement in R. pseudocacia.
Prasinoxanthin‐constaining Prasinophyceae Discovered in Jiaozhou Bay, China
Authors: Yu Zhi‐Gang , Deng Chun‐Mei , Yao Peng , Zhen Yu , Qian Shu‐Ben 
Published: April 2007

AbstractThe class Prasinophyceae (Chlorophyta) contains some photosynthetic eukaryotic ultraplankton species characterized by containing prasinoxanthin. The existence and abundance of these organisms can be estimated by the diagnostic pigment. We detected the unique pigments of prasinoxanthin‐containing Prasinophyceae in Jiaozhou Bay, China using high performance liquid chromatography (HPLC). This was the first finding of this kind in Chinese seas. Using the ratio of prasinoxanthin to chlorophyll a, the abundance of prasinoxanthin‐containing Prasinophyceae has been calculated. The average contribution of prasinoxanthin‐containing Prasinophyceae to the chlorophyll a pool was 8.5% and 17.0% in May and August 2004 in Jiaozhou Bay, and the maximums were 25.9% and 36.3%. Size fractionated pigment analysis suggested that more than 80% of prasinoxanthin were in the fraction of 2‐20 μm. According to the results of pigment and morphological analysis, the possible genera of prasinoxanthin‐containing Prasinophyceae and the reasons for causing this high abundant phytoplankton in Jiaozhou Bay were discussed. This kind of phytoplankton can not be discovered in traditional biological investigation, but its contribution to the coastal ecosystem is significant enough to be studied further.
Endopeptidase Isoenzyme Characteristics in Cucumis sativus Leaves During Dark‐induced Senescence
Authors: Zhang Peng , Wang Fei , Zhang Lie‐Feng , Rui Qi , Xu Lang‐Lai 
Published: April 2007

AbstractThe changes and characteristics of endopeptidase (EP) isoenzymes in cucumber (Cucumis sativus L.) leaves during dark‐induced senescence were investigated by activity staining after gradient‐polyacrylamide gel electrophoresis (G‐PAGE) containing co‐polymerized gelatin as substrate. The results showed that both the chlorophyll and the protein contents of leaves were decreased, and the protein degradation was correlated with the increase of proteolytic activity during the course of leaf senescence. Meanwhile, nine cucumber endopeptidases isoenzymes (CEP) with 140, 120, 106, 94, 76, 55, 46, 39 and 35 kDa molecular weights were detected. Four of these, CEP2, 3, 4 and CEP9 appeared all the time, but the changes of the activity were different during incubation. Another four CEPs (CEP5, 6, 7 and CEP8) whose activities increased with dark‐induced time were only detected in senescent leaves. Furthermore, the biochemical properties of these nine CEP were also characterized. All the CEPs had high activities from 35 °C to 45 °C, and the optimum temperature was found to be 40 °C. However, the activities of CEPs were not detected below 25 °C or over 60 °C. The activity bands appeared at a wide range of pH from 5.0 to 9.0, but the optimum pH was found at 7.0. No CEPs were detected at pH 4 or pH 10. By inhibition analysis we concluded that CEP2, 3, 4 and CEP9 were serine endopeptidases and CEP6 was a kind of cysteine protease. It is suggested that serine endopeptidases might play a major role in cucumber leaf senescence, and for the first time, six senescence‐related endopeptidases (CEP1, 5, 6, 7, 8 and 9) were found in cucumber leaves.
Novel Evidence for a Reversible Dissociation of Light‐harvesting Complex II from Photosystem II Reaction Center Complex Induced by Saturating Light Illumination in Soybean Leaves
Authors: Liao Yi , Xu Da‐Quan 
Published: April 2007

AbstractAfter saturating light illumination for 3 h the potential photochemical efficiency of photosystem II (PSII) (Fv/Fm, the ratio of variable to maximal fluorescence) decreased markedly and recovered basically to the level before saturating light illumination after dark recovery for 3 h in both soybean and wheat leaves, indicating that the decline in Fv/Fm is a reversible down‐regulation. Also, the saturating light illumination led to significant decreases in the low temperature (77 K) chlorophyll fluorescence parameters F685 (chlorophyll a fluorescence peaked at 685 nm) and F685/F735 (F735, chlorophyll a fluorescence peaked at 735 nm) in soybean leaves but not in wheat leaves. Moreover, trypsin (a protease) treatment resulted in a remarkable decrease in the amounts of PsbS protein (a nuclear gene psbS‐encoded 22 kDa protein) in the thylakoids from saturating light‐illuminated (SI), but not in those from dark‐adapted (DT) and dark‐recovered (DRT) soybean leaves. However, the treatment did not cause such a decrease in amounts of the PsbS protein in the thylakoids from saturating light‐illuminated wheat leaves. These results support the conclusion that saturating light illumination induces a reversible dissociation of some light‐harvesting complex II (LHCII) from PSII reaction center complex in soybean leaf but not in wheat leaf.
Effects of Local Nitrogen Supply on Water Uptake of Bean Plants in a Split Root System
Authors: Guo Shiwei , Shen Qirong , Brueck Holger 
Published: April 2007

AbstractTo study the effects of local nitrogen supply on water and nutrient absorption, French bean (Phaseolus vulgaris L.) plants were grown in a split root system. Five treatments supplied with different nitrogen forms were compared: homogeneous nitrate (NN) and homogenous ammonium (AA) supply, spatially separated supply of nitrate and ammonium (NA), half of the root system supplied with N‐free nutrient solution, the other half with either nitrate (N0) or ammonium (A0). The results showed that 10 d after onset of treatments, root dry matter (DM) in the nitrate‐supplied vessels treated with NA was more than two times higher than that in the ammonium‐supplied vessels. Water uptake from the nitrate‐supplied vessels treated with NA was 281% higher than under ammonium supply. In treatments N0 and A0, the local supply of N resulted in clearly higher root DM, and water uptake from the nitrate‐supplied vessels was 82% higher than in the ‐N vessels. However, in A0 plants, water uptake from the ‐N nutrient solution was 129% higher than from the ammonium‐supplied vessels. This indicates a compensatory effect, which resulted in almost identical rates of total water uptake of treatments AA and A0, which had comparable shoot DM and leaf area. Ammonium supply reduced potassium and magnesium absorption. Water uptake was positively correlated with N, Mg and K uptake.
High‐throughput Binary Vectors for Plant Gene Function Analysis
Authors: Lei Zhi‐Yong , Zhao Ping , Cao Min‐Jie , Cui Rong , Chen Xi , Xiong Li‐Zhong , Zhang Qi‐Fa , Oliver David J. , Xiang Cheng‐Bin 
Published: April 2007

AbstractA series of high‐throughput binary cloning vectors were constructed to facilitate gene function analysis in higher plants. This vector series consists of plasmids designed for plant expression, promoter analysis, gene silencing, and green fluorescent protein fusions for protein localization. These vectors provide for high‐throughput and efficient cloning utilizing sites for λ phage integrase/excisionase. In addition, unique restriction sites are incorporated in a multiple cloning site and enable promoter replacement. The entire vector series are available with complete sequence information and detailed annotations and are freely distributed to the scientific community for non‐commercial uses.
Salt Stress‐induced Programmed Cell Death in Rice Root Tip Cells
Authors: Li Jian‐You , Jiang Ai‐Liang , Zhang Wei 
Published: April 2007

AbstractSalt stressed rice root tips were used to investigate the changes of reactive oxygen species (ROS) and antioxidant enzymes at the early stages of programmed cell death (PCD). The results indicated that 500 mmol/L NaCl treatment could lead to specific features of PCD in root tips, such as DNA ladder, nuclear condense and deformation, and transferase mediated dUTP nick end labeling positive reaction, which were initiated at 4 h of treatment and progressed thereafter. Cytochrome c release from mitochondria into cytoplasm was also observed, which occurred at 2 h and was earlier than the above nuclear events. In the very early phase of PCD, an immediate burst in hydrogen peroxide and superoxide anion production rate was accompanied by two‐phase changes of superoxide dismutases and ascorbate peroxidase. A short period of increase in the activity was followed by prolonged impairment. Thus, we conclude that salt can induce PCD in rice root tip cells, and propose that in the early phase of rice root tip cell PCD, salt stress‐induced oxidative burst increased the antioxidant enzyme activity, which, in turn, scavenged the ROS and abrogated PCD. Also, when the stress is prolonged, the antioxidant system is damaged and accumulated ROS induces the PCD process, which leads to cytochrome c release and nuclear change.
Interdependence
Authors: Smith Joe , Clark Nigel , Yusoff Kathryn 
Published: April 2007

AbstractHow should we respond to the increasingly dense bundle of economic, cultural and ecological interconnections that span the globe and stretch into the future? What kinds of ethical and public engagements are demanded of researchers who work on global environmental, economic and social issues? The term interdependence may provide a powerful framework for advancing thinking and debate both within academia and among wider publics in relation to these questions. Members of the Open University's Geography Department have been working with partners to build the Interdependence Day project. The project combines research, cultural work, communications and public participation in an attempt to make sense of our responsibilities to people distant in space and time, and to the nonhuman natural world. This article reviews nearly a century of deployments of the term interdependence in political and academic writing, introduces the distinctive work that might be done with the term in the critical social sciences, and outlines the Interdependence Day project.
Memoryscape: How Audio Walks Can Deepen Our Sense of Place by Integrating Art, Oral History and Cultural Geography
Authors: Butler Toby 
Published: April 2007

AbstractThis article is concerned with the history and practice of creating sound walks or ‘memoryscapes’: outdoor trails that use recorded sound and spoken memory played on a personal stereo or mobile media to experience places in new ways. In this relatively new and rapidly evolving field, the author brings together works from music, sound art, oral history and cultural geography as a starting point to understanding how such trails can give us a more sophisticated and nuanced experience of places. He suggests that this might offer some exciting opportunities for practice‐based multimedia research and teaching.
China and Africa: Emerging Challenges to the Geographies of Power
Authors: Mawdsley Emma 
Published: April 2007

AbstractOver the last few years, China has assiduously pursued stronger economic and diplomatic relations with many Asian, African and Latin American countries. In part, this is fuelled by its extraordinary economic growth, which has led to a boom in domestic resource demand, and the search for profitable markets and investment outlets. China is also seeking diplomatic support in challenging the inequalities of ‘global’ governance. For better and worse, China's rise will lead to changes in the present structures and loci of power in an uneven world. This review article examines one set of China's ‘South–South’ interactions through an historical account of Sino–African relations from 1949 to the present day. It points to the complexity of interactions between diverse Chinese and African actors, a range of opportunities and problems, and the dangers of a defensive response from the West, if based on unreflexive and unsophisticated foreign policy analysis.
The Decline of Inner Suburbs: The New Suburban Gothic in the United States
Authors: Short John Rennie , Hanlon Bernadette , Vicino Thomas J. 
Published: April 2007

AbstractIn this article, we critically examine transformation and decline in US suburbs. We identify four distinct, chronological phases of development: suburban utopias, suburban conformity, suburban diversity, and suburban dichotomy. An element of this new suburban dichotomy is what we term suburban gothic. We theorize that the forces of an aging housing stock, land‐use planning, and deindustrialization contribute to the divergent realities of US suburbs.
Business Improvement Districts: Policy Origins, Mobile Policies and Urban Liveability
Authors: Ward Kevin 
Published: April 2007

AbstractThis article reviews the trans‐nationalisation of Business Improvement Districts. It outlines the geographical and ideological origins of this much‐heralded approach to downtown governance, and the means through which it has found itself in such diverse settings as Cape Town in South Africa, Kruševac in Serbia and Liverpool in the UK. Analysing the emergence of Business Improvement Districts in terms of the external edges of the state and its internal architecture, on the one hand, and, on the other, in the context of discussions around urban liveability, this article reviews work across geography, planning, political science and sociology. It concludes by arguing that Business Improvement Districts are both interesting in their own right, for what they reveal about contemporary trans‐national trends in urban governance, and for what they what they have to say about wider processes of neoliberal urbanisation.
Mycobacterium aviumin the Postgenomic Era
Authors: Turenne Christine Y. , Wallace Richard , Behr Marcel A. 
Published: April 2007

SUMMARYThe past several years have witnessed an upsurge of genomic data pertaining to theMycobacterium aviumcomplex (MAC). Despite clear advances, problems with the detection of MAC persist, spanning the tests that can be used, samples required for their validation, and the use of appropriate nomenclature. Additionally, the amount of genomic variability documented to date greatly outstrips the functional understanding of epidemiologically different subsets of the organism. In this review, we discuss how postgenomic insights into the MAC have helped to clarify the relationships between MAC organisms, highlighting the distinction between environmental and pathogenic subsets ofM. avium. We discuss the availability of various genetic targets for accurate classification of organisms and how these results provide a framework for future studies of MAC variability. The results of postgenomicM. aviumstudy provide optimism that a functional understanding of these organisms will soon emerge, with genomically defined subsets that are epidemiologically distinct and possess different survival mechanisms for their various niches. Although the status quo has largely been to study differentM. aviumsubsets in isolation, it is expected that attention to the similarities and differences betweenM. aviumorganisms will provide greater insight into their fundamental differences, including their propensity to cause disease.
Using Model-based Clustering to Improve Predictions for Queueing Delay on Parallel Machines
Authors: Brevik John , Nurmi Daniel , Wolski Rich 
Published: April 2007

Most space-sharing parallel computers presently operated by production high-performance computing centers use batch-queuing systems to manage processor allocation. In many cases, users wishing to use these batch-queued resources may choose among different queues (charging different amounts) potentially on a number of machines to which they have access. In such a situation, the amount of time a user's job will wait in any one batch queue can be a significant portion of the overall time from job submission to job completion. It thus becomes desirable to provide a prediction for the amount of time a given job can expect to wait in the queue. Further, it is natural to expect that attributes of an incoming job, specifically the number of processors requested and the amount of time requested, might impact that job's wait time. In this work, we explore the possibility of generating accurate predictions by automatically grouping jobs having similar attributes using model-based clustering. Moreover, we implement this clustering technique for a time series of jobs so that predictions of future wait times can be generated in real time. Using trace-based simulation on data from 7 machines over a 9-year period from across the country, comprising over one million job records, we show that clustering either by requested time, requested number of processors, or the product of the two generally produces more accurate predictions than earlier, more naive, approaches and that automatic clustering outperforms administrator-determined clustering.
AN EXPLORATION OF NON-ASYMPTOTIC LOW-DENSITY, PARITY CHECK ERASURE CODES FOR WIDE-AREA STORAGE APPLICATIONS
Authors: PLANK JAMES S. , THOMASON MICHAEL G. 
Published: April 2007

As peer-to-peer and widely distributed storage systems proliferate, the need to perform efficient erasure coding, instead of replication, is crucial to performance and efficiency. Low-Density Parity-Check (LDPC) codes have arisen as alternatives to standard erasure codes, such as Reed-Solomon codes, trading off vastly improved decoding performance for inefficiencies in the amount of data that must be acquired to perform decoding. The scores of papers written on LDPC codes typically analyze their collective and asymptotic behavior. Unfortunately, their practical application requires the generation and analysis of individual codes for finite systems. This paper attempts to illuminate the practical considerations of LDPC codes for peer-to-peer and distributed storage systems. The three main types of LDPC codes are detailed, and a huge variety of codes are generated, then analyzed using simulation. This analysis focuses on the performance of individual codes for finite systems, and addresses several important heretofore unanswered questions about employing LDPC codes in real-world systems.
The Cybernetic Stance: My Process and Purpose
Authors: Ascott Roy 
Published: April 2007

There is apparently a paradox in that, as artists, some of us become progressively process-oriented, but continue to produce art objects. For me this is necessary since I work on two levels from a common set of attitudes: on the social level, elaborating plans for a Cybernetic Art Matrix; on the intimate level making individual art works. Both processes are concerned with creating triggers—initiating creative behaviour in the observer/participant. Modern art is characterized by a behaviourist tendency in which process and system are cardinal factors. As distinctions between music, painting, poetry, etc. become blurred and media are mixed, a bahaviourist synthesis is seen to evolve, in which dialogue and feedback within a social culture indicate the emergence of a Cybernetic vision in art as in science. My artifacts come out of a process of random behaviour interacting with pre-established conditions. The Cybernetic Art Matrix is seen as a process in which anarchic group behaviour interacts with pre-established systems of communications, hardware and learning nets. In both cases the processes are self-generating and self-critical. Basically they are initiated by creative behaviour, and in turn give rise to its extension in other people.
Constitutive phosphoinositide 3-kinase/Akt activation represents a favorable prognostic factor in de novo acute myelogenous leukemia patients
Authors: Tamburini Jerome , Elie Caroline , Bardet Valérie , Chapuis Nicolas , Park Sophie , Broët Philippe , Cornillet-Lefebvre Pascale , Lioure Bruno , Ugo Valérie , Blanchet Odile , Ifrah Norbert , Witz Francis , Dreyfus François , Mayeux Patrick , Lacombe Catherine , Bouscary Didier 
Published: April 2007

Abstract
The phosphoinositide 3-kinase (PI3K/Akt) pathway is activated in acute myelogenous leukemia (AML) and is promising for targeted inhibition. Ninety-two patients with primary AML were analyzed for PI3K/Akt constitutive activation. Fifty percent of the patients presented with constitutive PI3K activation (PI3K +). No difference was observed between PI3K + and PI3K − groups concerning age, sex, white blood cell count, lactate dehydrogenase (LDH) level, bone marrow blast cells, French-American-British (FAB) classification, cytogenetics, RAS or nucleophosmin (NPM) mutations. Slightly more FLT3-ITD was detected in the PI3K − group (P = .048). The complete remission rate was similar between the 2 groups. With a median follow-up of 26 months, we observed for PI3K + and PI3K − patients, respectively, 56% and 33% overall survival (P = .001) and 72% and 41% relapse-free survival (P = .001). Constitutive PI3K/Akt activity is a favorable prognosis factor in AML, even after adjustment for FLT3-ITD, and may confer a particular sensitivity to chemotherapy. A better understanding of the downstream effectors of the PI3K/Akt pathway is needed before targeting in AML.