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Discriminative Canonical Correlation Analysis (DCCA) is a powerful supervised feature extraction technique for two sets of multivariate data, which has wide applications in pattern recognition. DCCA consists of two parts: (i) mean-centering that subtracts the sample mean from the sample; (ii) solving the generalized eigenvalue problem. The cost of DCCA is expensive when dealing with a large number of high-dimensional samples. To solve this problem, here we propose a quantum DCCA algorithm. Specifically, we devise an efficient method to compute the mean of all samples, then use block-Hamiltonian simulation and quantum phase estimation to solve the generalized eigenvalue problem. Our algorithm achieves a polynomial speedup in the dimension of samples under certain conditions over its classical counterpart.

An indole-related molecules have been considered as the potential fluorescent probes for biological and electrochemical sensing. However, most of the indole probes have been usually used in a single detection mode. Indolium probes that enable accurate detection in complex environments are rarely reported. Here, four novel indole derivatives including the phenyl group substituted with different functional moieties were designed on the basis of the donor-π-acceptor (D-π-A) concept. These derivatives exhibit positive solvatochromism owing to their varied molecular conformations upon contacting to various solvents and the different HOMO-LUMO gaps caused by the difference in electronic push-pull capability of the substituents. Their solid-state fluorescence emissions and multiple chromisms are observed due to the inherent twisted geometries and aggregation modes. In addition, these derivatives show dramatic color and fluorescence responses due to the protonation of the nitrogen and oxygen containing groups, and thus novel colorimetric pH sensors, fluorescent papers and logic gates have been designed.

Mean Centering (MC) is an important data preprocessing technique, which has a wide range of applications in data mining, machine learning, and multivariate statistical analysis. When the data set is large, this process will be time-consuming. In this paper, we propose an efficient quantum MC algorithm based on the block-encoding technique, which enables the existing quantum algorithms can get rid of the assumption that the original data set has been classically mean-centered. Specifically, we first adopt the strategy that MC can be achieved by multiplying by the centering matrix $C$, i.e., removing the row means, column means and row-column means of the original data matrix $X$ can be expressed as $XC$, $CX$ and $CXC$, respectively. This allows many classical problems involving MC, such as Principal Component Analysis (PCA), to directly solve the matrix algebra problems related to $XC$, $CX$ or $CXC$. Next, we can employ the block-encoding technique to realize MC. To achieve it, we first show how to construct the block-encoding of the centering matrix $C$, and then further obtain the block-encodings of $XC$, $CX$ and $CXC$. Finally, we describe one by one how to apply our MC algorithm to PCA and other algorithms.

Probing the orientation and oxygenation state of single molecules (SMs) is of great importance for understanding the advanced structure of individual molecules. Here, we manipulate molecules transporting through the hot spot of a sub-10 nm conical gold nanopore and acquire the multidimensional structural information of the SMs by surface enhanced Raman scattering (SERS) detection. The sub-10 nm size and conical shape of the plasmonic nanopore guarantee its high detection sensitivity. SERS spectra show a high correlation with the orientations of small-sized single rhodamine 6G (R6G) during transport. Meanwhile, SERS spectra of a single hemoglobin (Hb) reveal both the vertical/parallel orientations of the porphyrin ring and oxygenated/deoxygenated states of Hb. The present study provides a new strategy for bridging the primary sequence and the advanced structure of SMs.

To observe the histological and ultrastructural changes of the otopoint "Stomach" (MA-IC) area in chronic gastritis rabbits so as to provide a foundation for auricular acupoint diagnosis and treatment.A total of 20 New Zealand rabbits (half male and half female) were randomly and equally divided into control and model groups. The chronic gastritis model was established by gavage of 5% sodium salicylate each day for 5 weeks, while the rabbits of the control group received gavage of clear water at the same volume. Morphological changes of the tissues of gastric mucosa, otopoint "Stomach" and auricular control point were observed under light microscope after staining with hematoxylin-eosin (H.E.), and given scores (0-3 points) according to the levels of inflammatory cells. The ultrastructural changes of the otopoint "Stomach" tissue were observed under transmission electronic microscope (TEM).H.E. staining revealed smoothness of the gastric smooth muscle with no or a few of inflammatory cells in the control group, and appearance of gastric mucosal hemorrhage and erosion, slightly disordered epithelial glands and infiltration of a large number of lymphocytes in the mucosal layer with some clustered lymphocyte aggregation foci in the model group. The pathological score of gastric mucous in the model group was significantly higher than that in the control group (The otopoint "Stomach" tissue has structural damage and hyperplasia in chronic gastritis rabbits, suggesting a special correlation between the otopoint "Stomach" and gastric tissue, hence, providing a morphological basis for otopoint diagnosis and treatment.

International audience; The Poisson equation has wide applications in many areas of science and engineering. Although there are some quantum algorithms that can efficiently solve the Poisson equation, they generally require a fault-tolerant quantum computer, which is beyond the current technology. We propose a variational quantum algorithm (VQA) to solve the Poisson equation, which can be executed on noisy intermediate-scale quantum devices. In detail, we first adopt the finite-difference method to transform the Poisson equation into a linear system. Then, according to the special structure of the linear system, we find an explicit tensor product decomposition, with only (2log2n+1) items, of its coefficient matrix under a specific set of simple operators, where n is the dimension of the coefficient matrix. This implies that the proposed VQA needs fewer quantum measurements, which dramatically reduces the required quantum resources. Additionally, we design observables to efficiently evaluate the expectation values of the simple operators on a quantum computer. Numerical experiments demonstrate that our algorithm can solve the Poisson equation.

Cancer-associated fibroblasts (CAFs) play an essential role in supporting cancer progression. However, the details and consequent effects in response to the communication between CAFs and angiogenesis remain largely uninvestigated, especially in anticancer drug treatments. We found that cisplatin and 5-fluorouracil could induce fibroblast differentiation toward myofibroblasts via CCAAT/enhancer-binding protein delta (CEBPD) and consequently promote proliferation, migration, and in vitro tube formation of vascular endothelial cells and angiogenesis in vivo. Stromal-cell-derived factor 4 (SDF4) is responsive to anticancer drugs via CEBPD activation in CAFs and contributes to create a permissive environment for tumor cell angiogenesis and promotion of distant metastasis. Importantly, we demonstrated that SDF4 interacts with CXCR4 to trigger VEGFD expression through the activation of the ERK1/2 and p38 pathways in endothelial cells. Taken together, our novel findings support that SDF4 can be a therapeutic target in inhibition of angiogenesis for chemotherapy drug-administrated cancer patients.

Plasmonic materials with highly confined electromagnetic fields at resonance wavelengths have been widely used to enhance Raman scattering signals. To achieve the maximum enhancement, the resonance peaks of the plasmonic materials should overlap with the excitation and emission wavelengths of target molecules, which is difficult for most of the plasmonic materials possessing a few narrow resonance peaks. Here, we report an ultrabroadband plasmonic metamaterial absorber (BPMA) that can absorb 99% of the incident light energy and excite plasmon resonance from the ultraviolet to near-infrared range (250-1900 nm), which allows us to observe efficient plasmon-enhanced Raman scattering (PERS) with any excitation sources. As demonstrated by the investigation on a self-assembled monolayer of the nonresonant molecule 4-mercaptobenzonitrile, the BPMA exhibits high PERS performance with a detection limit of down to 10

Dimensionality reduction (DR) algorithms, which reduce the dimensionality of a given data set while preserving the information of the original data set as well as possible, play an important role in machine learning and data mining. Duan \emph{et al}. proposed a quantum version of the A-optimal projection algorithm (AOP) for dimensionality reduction [Phys. Rev. A 99, 032311 (2019)] and claimed that the algorithm has exponential speedups on the dimensionality of the original feature space $n$ and the dimensionality of the reduced feature space $k$ over the classical algorithm. In this paper, we correct the time complexity of Duan \emph{et al}.'s algorithm to $O(\frac{\kappa^{4s}\sqrt{k^s}} {\epsilon^{s}}\mathrm{polylog}^s (\frac{mn}{\epsilon}))$, where $\kappa$ is the condition number of a matrix that related to the original data set, $s$ is the number of iterations, $m$ is the number of data points and $\epsilon$ is the desired precision of the output state. Since the time complexity has an exponential dependence on $s$, the quantum algorithm can only be beneficial for high dimensional problems with a small number of iterations $s$. To get a further speedup, we propose an improved quantum AOP algorithm with time complexity $O(\frac{s \kappa^6 \sqrt{k}}{\epsilon}\mathrm{polylog}(\frac{nm}{\epsilon}) + \frac{s^2 \kappa^4}{\epsilon}\mathrm{polylog}(\frac{\kappa k}{\epsilon}))$ and space complexity $O(\log_2(nk/\epsilon)+s)$. With space complexity slightly worse, our algorithm achieves at least a polynomial speedup compared to Duan \emph{et al}.'s algorithm. Also, our algorithm shows exponential speedups in $n$ and $m$ compared with the classical algorithm when both $\kappa$, $k$ and $1/\epsilon$ are $O(\mathrm{polylog}(nm))$., Comment: 11 pages, 2 figures

Conventional ion current-based nanopore techniques that identify single molecules are hampered by limitations of providing only the ionic current information. Here, we introduce a silver nanotriangle-based nanopore (diameter < 50 nm) system for detecting molecule translocation using surface-enhanced Raman scattering. Rhodamine 6G is used as a model molecule to study the effect of an electric field (-1 V) on the mass transport. The four DNA bases also show significantly different SERS signals when they are transported into the plasmonic nanopore. The observations suggest that in the electric field, analyte molecules are driven into the nanopipette through the hot spot of the silver nanopore. The plasmonic nanopore shows great potential as a highly sensitive SERS platform for detecting molecule transport and paves the way for single molecule probing.

Silver nanoparticles (AgNPs) have been widely used as photocatalysts and nanosensors. Observation of the spectroscopy of a single AgNP greatly helps us understand the catalytic characteristics and morphology change of the AgNP during reactions. In the present study, AgNPs physically adsorbed on indium tin oxide (ITO) conductive glass were electrochemically reduced and oxidized, and the plasmonic resonance Rayleigh scattering (PRRS) spectrum of an individual AgNP was observed under a dark-field microscopy (DFM) equipped with a spectrometer. The electrochemical oxidization of the AgNP under constant potential caused a redshift of the PRRS peak for 30±5 nm. However, electrochemical reduction of the AgNP could not make the PRRS peak completely shift back to the initial position. In situ AFM and SEM characterization confirmed that very small Ag fragments (

Metal-organic frameworks (MOFs) have been successfully used as efficient quenchers for fluorescent DNA detection. However, the surface charge property of MOFs can inevitably affect their fluorescence quenching behavior. Herein, nanoscale MOFs (NMOFs), including MOF nanosheets and nanoparticles, have been employed to investigate the relationship between the fluorescence quenching and surface properties of NMOFs. We find that the positively and negatively charged NMOFs exhibited totally opposite fluorescence quenching properties toward negatively charged FAM-labeled double-stranded DNA (dsDNA). On the contrast, they show negligible influence on the sensing of positively charged TAMRA-labeled dsDNA. This study provides a new insight of the fluorescence quenching property of NMOFs and offers a new concept for construction of ratiometric fluorescence DNA biosensors.

An electrochemical sensor using ultralight and porous copper–nitrogen-doped graphene (CuNRGO) nanocomposite as the electrocatalyst has been constructed to simultaneously determine DNA bases such as guanine (G) and cytosine (C), adenine (A), and thymine (T). The nanocomposite is synthesized by thermally annealing an ice-templated structure of graphene oxide (GO) and Cu(phen)2. Because of the unique structure and the presence of Cu2+-N active sites, the CuNRGO exhibits outstanding electrocatalytic activity toward the oxidation of free DNA bases. After optimizing the experimental conditions, the CuNRGO-based electrochemical sensor shows good linear responses for the G, A, T, and C bases in the concentration ranges of 0.132–6.62 μM, 0.37–5.18 μM, 198.2–5551 μM, and 270.0–1575 μM, respectively. The results demonstrate that CuNRGO is a promising electrocatalyst for electrochemical sensing devices.

Nanopore structures have been successfully employed in next-generation DNA sequencing. For more complicated protein which normally contains 20 different amino acids, identifying the fluctuation of ionic current caused by different amino acids appears inadequate for protein sequencing. Therefore, it is highly desirable to develop size-controllable nanopores with optical activity that can provide additional structural information. Herein, we discovered the novel nanopore properties of the self-assembled ultramicroelectrodes originally developed by Bard and co-workers. Using a slightly modified method, the self-assembly of 7 ± 1 nm gold nanoparticles (AuNPs) can be precisely controlled to form a gold nanoporous sphere (GPS) on the tip of a glass capillary. Different dithiol linker molecules (1,3-propanedithiol, C3; 1,6-hexanedithiol, C6; and 1,9-nonanedithiol, C9) reproducibly led to rather similar nanopore sizes (5.07 ± 0.02, 5.13 ± 0.02, and 5.25 ± 0.01 nm), respectively. The GPS nanostructures were found to exhibit high ionic current rectification as well as surface-enhanced Raman scattering (SERS) activity due to the presence of nanopores and numerous "hot spots" among the cross-linked AuNPs on the surface of GPS. The rectification effect of the small nanopores was observed even under high concentration of electrolyte (290 mM), along with SERS enhancement factors well above 1 × 10

A crack-free sub-nanometer composite structure for the study of ion transfer was constructed by in situ growth of ZIF-90 [Zn(ICA)2, ICA=Imidazole-2-carboxaldehyde] on the tip of a glass nanopipette. The potential-driven ion transfer through the sub-nanometer channels in ZIF-90 is strongly influenced by the pH of the solution. A rectification ratio over 500 is observed in 1 m KCl solution under alkaline conditions (pH 11.58), which is the highest value reported under such a high salt concentration. Fluorescence experiments show the super-high rectification ratio under alkaline conditions results from the strong electrostatic interaction between ions and the sub-nanometer channels of ZIF-90. In addition to providing a general pathway for further study of mass-transfer process through sub-nanometer channels, the approach enable all kinds of metal–organic frameworks (MOFs) to be used as ionic permselectivity materials in nanopore-based analysis.

It is challenging to develop a robust nanoprobe for real-time operational and accurate detection of heavy metals in single cells. Fe-CN coordination chemistry has been well studied to determine the structural characteristics of hemeproteins by different techniques. However, the frequently used cyanide ligands are inorganic molecules that release cyanide anion under particular conditions and cause cyanide poisoning. In the present study, organic cyanide (4-mercaptobenzonitrile, MBN) was utilized for the first time in developing a facile nanoprobe based on surface-enhanced Raman scattering (SERS) for quantitative detection of hemeproteins (oxy-Hb) and trivalent iron (Fe3+) ions. The nanoprobe prepared by coating the glass capillary tip (100 nm) with a thin gold film, which enables highly localized study in living cell system. The cyanide stretching vibration in MBN was highly sensitive and selective to Fe3+ and oxy-Hb with excellent binding affinity (Kd 0.4 pM and 0.1 nM, respectively). The high sensitivity...

In the real environment, organisms are simultaneously exposed to different types of chemicals. Different types of chemicals usually have different time-dependent toxicity characteristics, however, people know little about the time-dependent toxicities of mixtures. Hence, the time-dependent toxicity of one pesticide, two ionic liquids (ILs), two antibiotics 20 ternary mixture rays and ten quaternary mixture rays to Vibrio qinghaiensis sp.-Q67 (V. qinghaiensis) were determined by the time-dependent microplate toxicity analysis. The results showed that the toxicity of pesticide (imidacloprid, IMI) to V. qinghaiensis does not change with time, the toxicities of two ILs (1-hexyl-3-methyl-imidazolium bromide, [hmim]Br, and 1-hexyl-3-methylimidazolium chloride, [hmim]Cl) decrease with time, and those of two antibiotics (chloramphenicol, CHL, and polymyxin B sulfate, POL) increase with time. The mixture toxicity almost doesn't change with time. Taking the concentration addition model as an additive reference, the combined toxicities of chemicals are assessed. It is shown that the mixture toxicities of most rays in two ternary mixture systems, [hmim]Br–IMI–CHL and [hmim]Cl–IMI–CHL, are additive at any time, while those in [hmim]Br–IMI–POL and [hmim]Cl–IMI–POL systems are antagonistic at some time, which implies that the POL may be a key component inducing the antagonism. To further validate the antagonism induced by POL, the POL is respectively merged into two ternary [hmim]Br–IMI–CHL and [hmim]Cl–IMI–CHL systems having no antagonism to form two quaternary mixture systems. It is found that many rays in the two new quaternary mixture systems have antagonistic action at some times, which validates that POL is indeed a key component. These findings indicate that the mixture toxicity of pesticide, ILs and antibiotics is complicated and prone to generate interaction, and doing risk assessment should take this type of mixtures into consideration.

DNA and amino acids are important biomolecules in living organisms. Probing such biomolecules with structural characters can provide valuable information for life study. Here, gold plasmonic nanopores (GPNs) with high SERS activity (a local enhancement factor higher than 109) are synthesized at the tip of a glass nanopipette. An electric field drives individual molecules to translocate through the GPNs, which enables in situ collection of the surface-enhanced Raman scattering (SERS). Nonresonant biomolecules, including nucleobases, amino acids, and oligonucleotides (DNA), with single nucleobase differences can be distinguished. The intensity of SERS is tunable by modulating the affinity between DNA and the GPNs. The present study shows the feasibility of applying a plasmonic nanopore to DNA and protein detection, which may also provide an easy way for tracking single molecule translocation by developing a well-defined single plasmonic nanopore.

A device of array nanochannels integrated with sensitive electrochemical detector has been designed to detect amyloid β (Aβ) peptide aggregation and inhibitor screening. Owing to the highly amplification capacity of array nanochannels, the change in ionic current upon Aβ peptide aggregation and inhibitor disaggregation can be easily monitored at micro-ampere level. Keywords: Nanochannels, Electrochemical detector, Amyloid β, Aggregation, Inhibitor screening

In the field of computational toxicology, predicting toxicological interaction or hormesis effect of a mixture from individuals is still a challenge. The two most frequently used model concentration addition (CA) and independent action (IA) also cannot solve these challenges perfectly. In this paper, we used IDV

This paper reported a new method to observe the catalytic progress of the natural horseradish peroxidase (HRP) in-situ on single gold nanoparticles (GNPs) by the combination of dark field imaging and plasmonic resonance scattering spectra. The produced single HRP-GNP exhibited localized catalytic property toward H2O2-Diaminobenzidine (DAB), which could be used to detect the concentration of H2O2 in micro/nanospace. The linear range for H2O2 sensing was from 0.01 μM to 5 μM with a detection limit of 10 nM. The new design strategy could be applied for a broader bioanalysis situation by substituting the HRP with other specified biocatalyst.

Single cell analysis is essential for understanding the heterogeneity, behaviors of cells, and diversity of target analyte in different subcellular regions. Nucleolin (NCL) is a multifunctional protein that is markedly overexpressed in most of the cancer cells. The variant expression levels of NCL in subcellular regions have a marked influence on cancer proliferation and treatments. However, the specificity of available methods to identify the cancer biomarkers is limited because of the high level of subcellular matrix effect. Herein, we proposed a novel technique to increase both the molecular and spectral specificity of cancer diagnosis by using aptamers affinity based portable nanopipette with distinctive surface-enhanced Raman scattering (SERS) activities. The aptamers-functionalized gold-coated nanopipette was used to capture target, while p-mercaptobenzonitrile (MBN) and complementary DNA modified Ag nanoparticles (AgNPs) worked as Raman reporter to produce SERS signal. The SERS signal of Raman nanotag was lost upon NCL capturing via modified DNA aptamers on nanoprobe, which further helped to verify the specificity of nanoprobe. For proof of concept, NCL protein was specifically extracted from different cell lines by aptamers modified SERS active nanoprobe. The nanoprobes manifested specifically good affinity for NCL with a dissociation constant K

The toxicity of a mixture depends not only on the mixture concentration level but also on the mixture ratio. For a multiple-component mixture (MCM) system with a definite chemical composition, the mixture toxicity can be predicted only if the global concentration additivity (GCA) is validated. The so-called GCA means that the toxicity of any mixture in the MCM system is the concentration additive, regardless of what its mixture ratio and concentration level. However, many mixture toxicity reports have usually employed one mixture ratio (such as the EC50 ratio), the equivalent effect concentration ratio (EECR) design, to specify several mixtures. EECR mixtures cannot simulate the concentration diversity and mixture ratio diversity of mixtures in the real environment, and it is impossible to validate the GCA. Therefore, in this paper, the uniform design ray (UD-Ray) was used to select nine mixture ratios (rays) in the mixture system of five nitrobenzene derivatives (NBDs). The representative UD-Ray mixtures can effectively and rationally describe the diversity in the NBD mixture system. The toxicities of the mixtures to Vibrio qinghaiensis sp.-Q67 were determined by the microplate toxicity analysis (MTA). For each UD-Ray mixture, the concentration addition (CA) model was used to validate whether the mixture toxicity is additive. All of the UD-Ray mixtures of five NBDs are global concentration additive. Afterwards, the CA is employed to predict the toxicities of the external mixtures from three EECR mixture rays with the NOEC, EC30, and EC70 ratios. The predictive toxicities are in good agreement with the experimental toxicities, which testifies to the predictability of the mixture toxicity of the NBDs.

This study examines the environmental effects on residential property values in an extremely compact city of Macao Peninsula. Results showed that people would be willing to pay more for apartment with sea view and proximity to public recreational park. The availability of sea view for an apartment would increase the sale price by approximately 20%. About 5% increase in price would be observed if the apartment was located within 200m to public recreational park. Proximity to sewage treatment plant had a negative influence on the apartment price. About 9% price drop would be observed if the apartment was within 200m to sewage treatment plant. In addition, the sale price of an apartment would increase by about 5% if it is close to a trunk road with high traffic volume, which implied that people living in an extremely compact city tended to sacrifice serenity for convenience.

The hormetic effects of ionic liquids (ILs) were paid more ecological attentions. However, the time-dependent hormetic effects of ILs and their mixtures remained to be studied. In this paper, the time-dependent toxicities of five single ILs, 1-ethyl-, 1-butyl-, 1-hexyl-, 1-octyl-, and 1-dodecyl-3-methylimidazolium chlorides (named as [C 2 mim]Cl, [C 4 mim]Cl, [C 6 mim]Cl, [C 8 mim]Cl, and [C 12 mim]Cl, respectively), and their five-component mixtures to Vibrio qinghaiensis sp.-Q67 were determined at five exposure time points. For single ILs, [C 2 mim]Cl displayed significant hormetic effects at 2, 4, 8, and 12 h; and [C 4 mim]Cl exhibited significant hormetic effects at 4, 8 and 12 h; while [C 6 mim]Cl, [C 8 mim]Cl and [C 12 mim]Cl have not significant hormetic effects. At the same time point, the longer the side chain is, the larger the inhibition at high concentration is, and the less the stimulation at low concentration is. Meanwhile, the maximum stimulation effects were found between 4 and 8 h. All six IL mixtures designed by uniform design ray showed significant hormetic effects at 8 and 12 h. By means of the variable selection and modeling method based on the prediction (VSMP), it was found that the higher the concentration of [C 2 mim]Cl is, the stronger the mixture hormetic effect is and the higher the concentration of [C 12 mim]Cl is, the weaker the hormetic effect is.

Recent toxicity studies on ionic liquids (ILs) are challenging their postulation as green solvents. Previous reports on mixtures containing ILs make it urgent to reveal the responsible components for the toxicity interactions. For that purpose, eight ILs, four consisting of 1-ethyl-3-methylimidazolium ([emim]) and the others of 1-butyl-3-methylimidazolium ([bmim]), were selected as mixture components. The concentrations of eight ILs in mixtures were set up by the uniform design. The inhibition toxicities of single ILs and mixtures to Vibrio qinghaiensis sp.-Q67 were determined by microplate toxicity analysis. Combined toxicity was evaluated by the difference between the effects observed and predicted by the concentration addition model. Using the variable selection and modeling method based on the prediction (VSMP), it was found that the antagonism/synergism induced by the mixtures of eight ILs was related to [emim]BF(4)/[emim]CF(3)SO(3). To further illustrate the toxicity interactions, eight ILs were split into two mixture groups, one containing four [emim]-based ILs and the other four [bmim]-based ILs. The [emim]-group exhibited synergism while [bmim]-group resulted in antagonism. It was interesting that both the synergism and antagonism well related to the concentration ratio of ILs with BF(4)(-). When ILs with BF(4)(-) were deleted from corresponding mixtures, the toxicity interactions (synergism/antagonism) disappeared.

Room-temperature ionic liquids (ILs) are a class of the salts in the liquid state. ILs typically consist of a bulky organic cation in combination with various anions and are designed to replace traditional volatile organic solvents in industry. However, it is not neglected that the possible release of ionic liquids into aquatic environments may lead to water pollution. We systematically investigated the effect of ILs on the luminescence of Vibrio qinghaiensis sp.-Q67 (Q67). When the ionic liquid, 1-ethyl-3-methyl imidazolium tetrafluoroborate ([emim]BF(4)), was exposed on Q67, the luminescence of Q67 was stimulated after 12 h and the maximal stimulatory amplitude (Emin) was surprisingly about 1000%. In comparison with the generally reported stimulating amplitude of about 30-60% such great stimulating effect induced by [emim]BF(4) was indeed unexpected. The main aim of this study was to systematically investigate the remarkable hormesis induced by [emim]BF(4). Results showed that there was good reproducibility on the observation of hormesis induced by [emim]BF(4) and such obvious hormesis had a close relation to the test organisms and exposure time. In addition, we confirmed that this surprising phenomenon did not only depend on range and spacing of exposure concentration of ILs but also on their structure components. Only joint influence of both anion, BF(4)(-) and ethyl side chain of cation made [emim]BF(4) induce such remarkable hormesis on Q67. The experimental findings of hormesis induced by [emim]BF(4) provided a good case for the hormesis database.

Flavonoids are widely distributed in the plant kingdom and have broad-spectrum pharmacological activities and extensive bio- logical effects. The pharmacological investigations indicated that flavonoids can regulate the structure and functions of proteins and nu- cleic acids by controlling their signaling pathways and expressions to achieve their effects. In this review, the main approaches for inves- tigating the interaction of flavonoids with biomacromolecules in vitro and related theoretical issues were presented and some important parameters including their binding constants, the number of binding site, and the position of the flavonoids on the protein have been summarized. The investigation details of the interaction mechanisms and binding mode were compared and discussed. The binding sites of flavonoids on the protein were usually determined by replacement experiments using warfarin (WAR) (site I) and ibuprofen or diaze- pam (site II) as site markers, and the structural alterations of the protein or flavonoids before and after the combinations were probed by Fourier transform infrared (FTIR), circular dichroism (CD) or UV absorption methods. Flavonols attracted much attention due to their special structural features and spectroscopic characteristics. The interaction of nucleic acids with flavonols has been the focus of exten- sive research in recent years. Investigation of the interaction between flavonoids and biomacromolecules can provide useful knowledge for optimizing molecular structure of the drugs, prescriptions and route of administration, and also the information for their bioavailabil- ity and bioactivity.

Compound contamination and toxicity interaction necessitate the development of models that have an insight into the combined toxicity of chemicals. In this paper, a novel and simple model dependent only on the mixture information (MIM), was developed. Firstly, the concentration-response data of seven groups of binary and multi-component (pseudo-binary) mixtures with different mixture ratios to Vibrio qinghaiensis sp.-Q67 were determined using the microplate toxicity analysis. Then, a desirable non-linear function was selected to fit the data. It was found that there are good linear correlations between the location parameter (α) and mixture ratio (p) of a component and between the steepness (β) and p. Based on the correlations, a mixture toxicity model independent of pure component toxicity profiles was built. The model can be used to accurately estimate the toxicities of the seven groups of mixtures, which greatly simplified the predictive procedure of the combined toxicity.

Apoptosis is an erratic physiological process whereby cells undergo a self-destruction process. A quantitative analysis of apoptosis, namely counting the number of cells undergoing apoptosis, is required not only to understand the mechanism of this process but also to quantitatively evaluate the effect of anticancer drugs as many anticancer drugs attempt to achieve their effects by inducing the cancer cell to apoptosis. Currently, counting cells undergoing apoptosis is generally carried out manually by the naked eyes. Although these methods are accurate and appropriate in some cases, they can be extremely time consuming and labor intensive. Also, manual counting is subjective and difficult to achieve high throughput. There is compelling necessity for developing an automatic apoptosis-counting method. In this paper, we described an image-based method, which is applied in HCT116 human colon adenocarcinoma cell culture to count the number of apoptosis induced by anticancer drug oxaliplatin. Our methods are mostly based on well-known and mature algorithms in image processing and pattern recognition such as the contrast-limited adaptive histogram equalization, pixel classification, size distribution detection by granulometries, watershed algorithm, and artificial neural networks. We evaluated our segmentation results using the area overlap measurement, and the best achieved performance that can reach over 98%. We also evaluated our apoptosis detection results against the results of four biomedical experts and compared the results with other existing efforts. The final performance shows that our method is more reliable and accurate for detecting apoptosis than the previous methods.

In order to upgrade the WebGIS legacy systems smoothly, and improve the response speed of traditional WebGIS and user experience, this paper designs and develops a tile map service based on middleware technology. Through systematic analysis of its basic principle and system architecture, this paper gives several optimization strategies. Finally, we make a performance comparison between tile map service middleware and traditional OGC (Open Geospatial Consortium, OGC) standard WMS service. Our experimental results show that the average response time of tile map service reduced by 46% than sending WMS request to WMS server directly, and the TMS middleware has a high efficiency when cutting map tiles dynamically because of its meta-tiling strategy. The study shows that tile map service middleware has important application value both in improving traditional WebGIS performance and in upgrading existing legacy systems.

BACKGROUND: Environmental pesticides, including insecticides and herbicides, are frequently encountered as mixtures and threaten non-target organisms in water. Evaluation of the combined toxicity of diverse pesticides with various concentration combinations is important, especially using limited experimental effort. Uniform design (UD) is one optimal experimental technique that can rationally arrange the concentrations of mixture components so that, with a minimum number of experimental runs, the combined toxicity of multiple pesticide mixtures can be evaluated. RESULTS: The concentration compositions of 18 pesticide mixture points designed by UD covered almost all possible concentration ranges of the mixture components on account of the two merits of 'space filling' and 'multiple levels'. The combined toxicities of 18 mixture rays extended by using the fixed-ratio ray design (FRRD) from 18 UD mixture points were evaluated by concentration addition (CA) and independent action (IA) models. It was found that the concentration-response curves (CRCs) predicted by CA were, on the whole, located between the 95% confidence intervals of the experimental CRCs, which implied that the combined toxicity of the pesticide mixture rays could be evaluated by CA. The CRCs predicted by IA were very similar to those from CA. CONCLUSION: The model developed from the UD mixture rays can effectively simulate mixtures with arbitrary concentration compositions of 15 pesticides. The CA model can accurately evaluate and predict the combined toxicity of the pesticides, which provides a useful tool for risk assessment of a mixture of multiple pesticides in the aquatic environment.