Boqiang Qin

Nanjing Institute of Geography and Limnology, Chinese Academy of Science, Taihu Lab for Lake Ecosystem Research, Faculty Member

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Papers by Boqiang Qin

Lake eutrophication and its ecosystem response

Chinese Science Bulletin, 2012

China is a country with many lakes, about one-third of which are freshwater mainly distributed in... more China is a country with many lakes, about one-third of which are freshwater mainly distributed in the middle and lower reaches of the Yangtze River. Currently most of the lakes are mesotrophic or eutrophic. Lake eutrophication has become one of the major ecological and environmental problems faced by lakes in China and can lead to a series of abnormal ecosystem responses, including extinction of submerged plants, frequent occurrence of cyanobacterial blooms, increased microbial biomass and productivity, decreased biodiversity, accelerated cycles, and a change in the efficient use of nutrients. With development of eutrophication, the whole lake ecosystem suffers decreased biodiversity, simplification of biotic community structure, instability of the ecosystem, and ultimately the clear-water, macrophyte-dominated ecosystem gradually shifts to a turbid-water, algae-dominated ecosystem. This ecosystem succession mechanism is speculated to be caused by different nutrient utilization efficiencies of macrophytes and phytoplankton. The ultimate ecosystem succession trend of seriously eutrophic lakes is that a phytoplankton-dominated autotrophic lake shifts to a heterotrophic lake dominated by micro-organisms, protozoans.

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[Chromophoric dissolved organic matter absorption characteristics with relation to fluorescence in typical macrophyte, algae lake zones of Lake Taihu]

Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.], 2005

Chromophoric dissolved organic matter (CDOM) represents one of the primary light-absorbing specie... more Chromophoric dissolved organic matter (CDOM) represents one of the primary light-absorbing species in natural waters and plays a critical in determining the aquatic light field. CDOM shows a featureless absorption spectrum that increases exponentially with decreasing wavelength, which limits the penetration of biologically damaging UV-B radiation (wavelength from 280 to 320 nm) in the water column, thus shielding aquatic organisms. CDOM absorption measurements and their relationship with dissolved organic carbon (DOC), and fluorescence are presented in typical macrophyte and algae lake zone of Lake Taihu based on a field investigation in April in 2004 and lab analysis. Absorption spectral of CDOM was measured from 240 to 800 nm using a Shimadzu UV-2401PC UV-Vis recording spectrophotometer. Fluorescence with an excitation wavelength of 355 nm, an emission wavelength of 450 nm is measured using a Shimadzu 5301 spectrofluorometer. Concentrations of DOC ranged from 6.3 to 17.2 mg/L with...

Variability of bacterioplankton in the north zone of Lake Taihu [J]

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A comparative study on seasonal variations of crustaceans in the different lake areas in Lake Taihu

A comparative study on the crustaceans had been carried out in three different trophic areas (the... more A comparative study on the crustaceans had been carried out in three different trophic areas (the open water area, Meiliang Bay, Lake Wulihu) in Lake Taihu from Oct. 2003 to Sep. 2004. The trophic level was the highest in Lake Wulihu and the lowest in the open water area. The biggest values of abundance and biomass of crustaceans were occurred in Meiling Bay, while the smallest values were founded in Lake Wulihu. There was a similar pattern in the seasonal variation of crustaceans in the three areas. The highest abundance of crustaceans was occurred in summer and the lowest abundance in winter in all areas. Bosmina coregoni and Ceriodaphnia cornuta were the first and second dominant species of crustaceans in Meiliang Bay and the open water area. However, in Lake Wulihu the dominant species of crustaceans was Moina macrocopa. Correlation analysis indicated positive relationships between abundance of copepods, cladocerans and TP, water temperature. The structure of crustacean community was affected by the eutrophication in Lake Taihu.

Expert system for predicting the silicon content in hot metal based on RBF neural network [J]

Management of water environment in small watershed with Hufu town of Yixing city as example

In order to study the management of water environment in small watershed, the SWAT model is used ... more In order to study the management of water environment in small watershed, the SWAT model is used to study Hufu watershed of Yixing city where the non-point output predominates. From the relation between social economic development and water environment, the studies couple up the model of land evolution and the water environment simulated model to put forward suggestions of management. At first, the field data are used to validate the SWAT model for determining its efficiency. Then the total output level of pollutants in the area and the contribution of each pollution source are calculated; and according to simulating outcome, concrete suggestions are put forward. Then supported with GIS technique, the MARCOV model is used to simulate the evolution of land cover. In the end, these two models are coupled up to study the influence of social economic development on water environment. The possible output of pollutants are predicted and the influence of social economic development is evaluated.

The Prevalence of HIV and Syphilis Infection Among Drug Addicts at a Detoxification Unit [J]

Phosphorylation of microtubule-binding protein Hec1 by mitotic kinase Aurora B specifies spindle checkpoint kinase Mps1 signaling at the kinetochore

Background: Hec1 is a core component of outer kinetochore essential for chromosome segregation in... more Background: Hec1 is a core component of outer kinetochore essential for chromosome segregation in mitosis. Results: Hec1 interacts with mitotic checkpoint kinase Mps1, and phosphorylation of Hec1 by Aurora B recruits Mps1 to kinetochore. Conclusion: Phosphorylation of Hec1 by Aurora B specifies Mps1 signaling at the kinetochore. Significance: Aurora B-Hec1-Mps1 axis orchestrates chromosome dynamics and stability in mitosis.

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Absorption of light by chromophoric dissolved organic matter (CDOM) in Meiliang Bay of Taihu Lake

In different lake regions in Meiliang Bay of Taihu Lake, absorption of light by CDOM, change of l... more In different lake regions in Meiliang Bay of Taihu Lake, absorption of light by CDOM, change of light attenuation coefficients and relationship with DOC concentration, contribution rate of absorption of CDOM to light attenuation coefficient and exponential slope coefficients were explored. The CDOM coefficient differed obviously in different lake regions; the change range of ad(440) and ad(320) was 1.22~2.58m-1 and 6.24~10.69m-1, respectively. The highest and lowest DOC concentrations were in mouth of Liangxi River and mouth of Meiliang Bay with a maximum value 12.74mg/L and a minimum value 7.87mg/L, respectively, tending to decrease gradually from inside to mouth of the bay; and a significant linear relationship was found between DOC concentrations and CDOM absorption coefficients under 320nm. The contribution rate of CDOM absorption to light attenuation coefficient changed in 0.69%~60.9% at 320~700nm. The contribution rates were more than 20% during the ultraviolet range at 280~440nm, and the values were higher in Wuli Lake and river mouth area than those in inside of Meiliang Bay and littoral belt. The exponential slope coefficient S of CDOM was 13.9 to 18.1m-1 at 280~440nm.

Pollen-based reconstruction of vegetation patterns of China in mid-Holocene

Science in China Series D: Earth Sciences, 1998

Biomization provides an important way to assign pollen taxa to biomes and to simulate palaeo-vege... more Biomization provides an important way to assign pollen taxa to biomes and to simulate palaeo-vegetation patterns, so that pollen data can be mapped to reconstruct biogeography and climate. The authors have tested the applicability of this procedure to assign modern pollen surface samples from China to biomes. The procedure successfully delineated the major vegetation types of China. When the same

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A new identity based signcryption scheme in the standard model

ABSTRACT Signcryption is a useful cryptographic primitive which simultaneously performs encryptio... more ABSTRACT Signcryption is a useful cryptographic primitive which simultaneously performs encryption and signature with cost less than the signature-then-encryption approach. Identity-based signcryption (IBSC) eliminates the complicated management of certificates in signcryption schemes in the traditional public-key infrastructure (PKI) setting. Most IBSC schemes are constructed in the random oracle model, while it is unknown how to instantiate a really &quot;random&quot; oracle in the real world. By exploiting Boneh et al.&#39;s strongly unforgeable signature and Paterson et al.&#39;s identity-based signature, this paper proposes a new IBSC scheme in the standard model. It is proven that our IBSC scheme satisfies semantic security and strong unforgeability under the bilinear decision Diffie-Hellman (BDDH) assumption. The proofs do not rely on random oracles. Performance analysis shows that our scheme is also efficient and practical.

Simultaneous authentication and secrecy in identity-based data upload to cloud

Most existing works to secure cloud devote to remote integrity check, search and computing on enc... more Most existing works to secure cloud devote to remote integrity check, search and computing on encrypted data. In this paper, we deal with simultaneous authentication and secrecy when data are uploaded to cloud. Observing that cloud is most interesting to companies in which multiple authorized employees are allowed to upload data,

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CistromeFinder for ChIP-seq and DNase-seq data reuse

Chromatin immunoprecipitation and DNase I hypersensitivity assays with high-throughput sequencing... more Chromatin immunoprecipitation and DNase I hypersensitivity assays with high-throughput sequencing have greatly accelerated the understanding of transcriptional and epigenetic regulation, although data reuse for the community of experimental biologists has been challenging. We created a data portal CistromeFinder that can help query, evaluate and visualize publicly available Chromatin immunoprecipitation and DNase I hypersensitivity assays with highthroughput sequencing data in human and mouse. The database currently contains 6378 samples over 4391 datasets, 313 factors and 102 cell lines or cell populations. Each dataset has gone through a consistent analysis and quality control pipeline; therefore, users could evaluate the overall quality of each dataset before examining binding sites near their genes of interest. CistromeFinder is integrated with UCSC genome browser for visualization, Primer3Plus for ChIP-qPCR primer design and CistromeMap for submitting newly available datasets. It also allows users to leave comments to facilitate data evaluation and update.

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Controlling cyanobacterial blooms in hypertrophic Lake Taihu, China: will nitrogen reductions cause replacement of non-N2 fixing by N2 fixing taxa?

PloS one, 2014

Excessive anthropogenic nitrogen (N) and phosphorus (P) inputs have caused an alarming increase i... more Excessive anthropogenic nitrogen (N) and phosphorus (P) inputs have caused an alarming increase in harmful cyanobacterial blooms, threatening sustainability of lakes and reservoirs worldwide. Hypertrophic Lake Taihu, China's third largest freshwater lake, typifies this predicament, with toxic blooms of the non-N2 fixing cyanobacteria Microcystis spp. dominating from spring through fall. Previous studies indicate N and P reductions are needed to reduce bloom magnitude and duration. However, N reductions may encourage replacement of non-N2 fixing with N2 fixing cyanobacteria. This potentially counterproductive scenario was evaluated using replicate, large (1000 L), in-lake mesocosms during summer bloom periods. N+P additions led to maximum phytoplankton production. Phosphorus enrichment, which promoted N limitation, resulted in increases in N2 fixing taxa (Anabaena spp.), but it did not lead to significant replacement of non-N2 fixing with N2 fixing cyanobacteria, and N2 fixation ...

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Who Is Touching My Cloud

Lecture Notes in Computer Science, 2014

Advanced access controls have been proposed to secure sensitive data maintained by a third party.... more Advanced access controls have been proposed to secure sensitive data maintained by a third party. A subtle issue in such systems is that some access credentials may be leaked due to various reasons, which could severely damage data security. In this paper, we investigate leakage tracing enabled access control over outsourced data, so that one can revoke the suspected leaked credentials or prepare judicial evidences for legal procedure if necessary. Specifically, we propose a leaked access credential tracing (LACT) framework to secure data outsourced to clouds and formalize its security model. Following the framework, we construct a concrete LACT scheme that is provably secure. The proposed scheme offers fine-grained access control over outsourced data, by which the data owner can specify an access policy to ensure that the data is only accessible to the users meeting the policy. In case of suspectable illegal access to outsourced data with leaked credentials, a tracing procedure can be invoked to tracing in a black-box manner at least one of the users who leaked their access credentials. The tracing procedure can run without the cloud service provider being disturbed. Analysis shows that the introduction of tracing access credential leakage incurs little additional cost to either data outsourcing or access procedure.

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Vector–soliton bound states for the coupled mixed derivative nonlinear Schrödinger equations in optical fibers

Wave Motion, 2013

In this paper, the vector-soliton bound states (VSBSs) are investigated for the coupled mixed der... more In this paper, the vector-soliton bound states (VSBSs) are investigated for the coupled mixed derivative nonlinear Schrödinger equations, which can describe the pulse propagation in the femtosecond regime of birefringent optical fibers. Symmetric and asymmetric VSBSs with the periodic collisions are obtained and analyzed. The intensity profile and collision period of the bound state are related to the ratio of the real parts of two wavenumbers. The separation factors are introduced in the solutions to linearly adjust the soliton separations. Amplitude-changing collisions between the VSBS and vector bright solitons are also obtained. Via the split-step Fourier method, stability analysis shows that the VSBSs can resist the finite initial perturbations. In addition, the derivative cubic nonlinearity and cubic nonlinearity terms are found to both have no influence on the types of VSBSs, but leads to one-sided compression, center shifts and amplitude decrease of the VSBSs. Energy-exchanging phenomena during the amplitude-changing collisions are not affected, either.

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Water and Sediment Quality in Lakes along the Middle and Lower Reaches of the Yangtze River, China

Water Resources Management, 2012

ABSTRACT Water and sediment samples were collected from 45 lakes along the middle-lower Yangtze R... more ABSTRACT Water and sediment samples were collected from 45 lakes along the middle-lower Yangtze River, China. Each lake was sampled seasonally, over a period of one year. Water quality variables and metals in sediments were measured. Lakes along the lowest part of the river, within the Yangtze River Delta, had highest nutrient concentrations and were eutrophic or hypereutrophic. Lakes displayed a gradient in many water chemistry variables, from the middle to the lower Yangtze River. Lakes of the Delta region had the highest conductivity, sulfate, turbidity, and Chl-a values, and the lowest dissolved oxygen concentrations. A number of lakes near urban areas in the study region also displayed similar conditions. Lakes polluted by heavy metals were found in the upper part of the lower Yangtze River and had high Cu, Cr, and Co concentrations in sediments. The mean Igeo (index of geoaccumulation) values for Cu, Cr, and Co classes ranged from 0 to 4, indicating moderate to heavy contamination, contributed mainly from untreated industrial waste water produced within the lake catchments. Lakes of the middle Yangtze River are generally in relatively better condition, except for those around urban zones, which experience higher nutrient and heavy metal loading. The spatial distribution of lake conditions in the area can be related to the policy of regional economic development. The Delta region in China is developed and includes such cities as Shanghai and Suzhou. Heavy industries have moved into the interior region of China too, and development of modern cities is now occurring under some level of environmental protection. Nevertheless, lakes in the central part are becoming seriously polluted with both heavy metals and nutrients because local authorities promote industrialization and urbanization to improve economic conditions, while often ignoring environmental protection. Pollution is increasingly occurring in upstream reaches, a tendency that will bring more environmental problems. Interior lakes of China require immediate attention to prevent further declines in water quality.

Folding-promoted TBAX-mediated selective demethylation of methoxybenzene-based macrocyclic aromatic pentamers

Organic & Biomolecular Chemistry, 2012

Described in this study is the ability of tetrabutylammonium salts (TBAX) to mediate an efficient... more Described in this study is the ability of tetrabutylammonium salts (TBAX) to mediate an efficient mono- or di-demethylation removing one or two out of five aromatic methoxy methyl groups situated in similar chemical microenvironments in a H-bonded macrocyclic aromatic pentamer. These demethylations are found to be both chemo- and regioselective, and promoted by the H-bonding directed folding of the macrocyclic backbone.

Soliton interactions in a generalized inhomogeneous coupled Hirota–Maxwell–Bloch system

Nonlinear Dynamics, 2011

In this paper, via the Darboux transformation, with symbolic computation, the bright oneand two-s... more In this paper, via the Darboux transformation, with symbolic computation, the bright oneand two-soliton solutions for a generalized inhomogeneous coupled Hirota-Maxwell-Bloch system are obtained in an inhomogeneous nonlinear dispersive fiber doped with two-level resonant atoms. The study on the bright soliton collision shows that in this system, there exists the complete or partial energy exchange. Through the asymptotic analysis, some physical quantities are discussed. Energy transfer in the two-soliton collision might have potential applications in the study of pulse amplification. In addition, the conservation laws for the system are also constructed.

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Persistently Folded Circular Aromatic Amide Pentamers Containing Modularly Tunable Cation-Binding Cavities with High Ion Selectivity

Journal of the American Chemical Society, 2010

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