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The interactions between bovine serum albumin (BSA) and four lactic acid-based deep eutectic solvents (LADESs) were studied by spectroscopic and electrochemical methods under simulated physiological conditions.

G-quadruplex structure (G4) is a type of DNA secondary structure that widely exists in the genomes of many organisms. G4s are believed to participate in multiple biological processes. Acyl-CoA binding protein (ACBP), a ubiquitously expressed and highly conserved protein in eukaryotic cells, plays important roles in lipid metabolism by transporting and protecting acyl-CoA esters. Here, we report the functional identification of a G4 in the promoter of the ACBP gene in silkworm and human cancer cells. We found that G4 exists as a conserved element in the promoters of ACBP genes in invertebrates and vertebrates. The BmACBP G4 bound with G4-binding protein LARK regulated BmACBP transcription, which was blocked by the G4 stabilizer pyridostatin (PDS) and G4 antisense oligonucleotides. PDS treatment with fifth instar silkworm larvae decreased the BmACBP expression and triacylglycerides (TAG) level, resulting in reductions in fat body mass, body size and weight and growth and metamorphic rates. PDS treatment and knocking out of the HsACBP G4 in human hepatic adenocarcinoma HepG2 cells inhibited the expression of HsACBP and decreased the TAG level and cell proliferation. Altogether, our findings suggest that G4 of the ACBP genes is involved in regulation of lipid metabolism processes in invertebrates and vertebrates.

G-quadruplex structures (G4s) have been identified in genomes of multiple organisms and proven to play important epigenetic regulatory roles in various cellular functions. However, the G4 formation mechanism remains largely unknown. Here, we found a negative correlation between DNA 5mC methylation and G4 abundance. The abundance of genomic G4s significantly increased when the whole-genome methylation level was reduced in DNMT1-knockout cells. This increase was then suppressed by DNMT1 over-expression. And more G4s were detected in the hypomethylated cancer cell line HepG2 and rectal cancer tissues. Besides, 5mC modification significantly inhibited G4 formation of the potential G-quadruplex sequences (PQSs). The transcription of genes with 5mC modification sites in their promoter PQSs was affected after treatment with G4 stabilizer pyridostatin or methylation inhibitor 5-aza-dC. The global reduction of genomic methylation elevates gene transcription levels through increased G4s. Taken together, DNA 5mC methylation prevents PQSs from folding into G4s in genomes.

Insect cuticle is an apical extracellular matrix produced by the epidermis, tracheal, hind- and foregut epithelia during embryogenesis and renewed during moulting and metamorphosis. However, the underlined regulatory mechanism for embryonic cuticle formation remains largely unclear. Here, we investigate the function of the transcription factor POUM2 in the embryonic cuticular formation in Bombyx mori, a model lepidopteran insect. CRISPR/Cas9-mediated knockout of POUM2 resulted in the defect of cuticular deposition, pigmentation and sclerotization in the embryos. Differentially expressed transcripts analysis of 7-day-old embryos identified 174 up- or down-regulated cuticular protein transcripts, eight up-regulated chitin degradation transcripts, two down-regulated chitin synthesis transcripts and 48 up- or down-regulated transcription factor transcripts in the POUM2

To investigate the topological alterations of the whole-brain white matter structural networks in episodic migraine (EM) without aura. Forty-five EM patients without aura and 35 age- and sex-matched healthy controls were registered, and underwent diffusion tensor MRI acquisition at interictal. Graph theory-based analyses were then performed for the characterization of brain structural network properties. Pearson correlation analysis was performed on each network metric between the EM patients and healthy controls. The EM patients exhibited abnormal global network properties and local network topology that were characterized by more strongly integrated, more efficient, and faster information transferring. These network differences were widely located in the occipital, temporal, and parietal regions. Additionally, the local efficient of global parameters showed positive correlation with visual analogue scale, and along with prolonging disease duration, the nodal efficiency would be reduced, and the nodal shortest path length would be increased. Headache Impact Test version 6 scores have negative correlation with the nodal shortest path length, and positive correlations with the nodal efficiency. The results indicate that EM patients had aberrant topological structure and make a better understanding of structural connectivity in EM; it may provide imaging evidence for clinical study of migraine pathogenesis.

A multiparameter observation task includes a comprehensive theme with multiple indispensable parameters that need to be monitored simultaneously. However, with limited observation sensor resources for a multiparameter observation task, the spatial misalignment of the coverage area of each parameter decreases the observation efficiency, especially in a space-ground sensor network. To solve this problem, we developed a collaborative planning method in the sensor planning phase. With this method, a space-ground maximal coverage model with multiple parameters (SGMC-MP) was introduced. The proposed collaborative planning method cooperatively utilizes the space-ground sensors to make an observation plan. This method aims to maximize the overlay coverage range among the parameters in the task to reduce the spatial misalignment and improve the utilization of the sensors. The proposed method was applied to a multiparameter observation task in the Three Gorges Reservoir Area in Chongqing. The results indicate that the proposed method exhibits better coverage performance for sensor planning in the multiparameter observation task than the traditional separate planning method. In addition, planning strategies, coverage flexibility, model extension, and algorithm comparison are further discussed.

To investigate the correlation between choroid plexus volume and whole brain morphology in patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD).Fifty-one patients with MS, 42 patients with NMOSD, and 56 healthy controls (HC) were recruited. The morphological changes in choroid plexus and whole brain tissue were compared between three groups and the correlations between choroid plexus volume and brain atrophy were further investigated. The longitudinal alterations of brain morphology in 25 MS and 20 NMOSD patients were compared.Compared to the HC group, the choroid plexus volumes were increased in the MS group (p0.001) but not in the NMOSD group (p0.05). Compared to the HC group, the MS group showed reduced cortex thickness, deep gray matter volume, and increased ventricle system volume, and the NMOSD group showed increased third ventricle volume (all p0.05, false discovery rate corrected). In the MS group, there were widespread correlations between enlarged choroid plexus volume and reduced cerebral cortex thickness (p0.05, r = -0.292~-0.538, false discovery rate corrected). The interval time was not significantly different between the MS (median: 1.37 years) and NMOSD group (median: 1.25 years) (p0.05). In MS, compared with the baseline, the right hippocampus and nucleus accumbens volumes were decreased in long follow-up, and bilateral lateral ventricle volumes were increased both in short and long follow-up (all p0.05, false discovery rate corrected).The enlarged choroid plexus related to reduced cortical thickness and progressive local brain atrophy are shown in MS patients, but not obvious in NMOSD patients.• MS and NMOSD have different altered patterns in choroid plexus volume and brain atrophy. • The enlarged choroid plexus related to brain atrophy is shown in MS patients, but not obvious in NMOSD patients. • Progressive local brain atrophy is shown in MS patients, but not obvious in NMOSD patients.

Objective: Through the spatial optimal allocation of land resources to improve the efficiency of land use, promote the rational layout of various industries and infrastructure, and provide a theoretical basis for the comprehensive development of regional social economy. Methods: Combining GIS spatial analysis technology, logistic regression analysis method and CLUE-S model, taking Kaishan Fengweihan City, Laos, as the research area, the research on the spatial optimal allocation of land resources was carried out. Under the constraints of spatial suitability and quantitative structure, the spatial optimal allocation of land resources in Fengweihan city of Kaishan is carried out based on the land demand, limiting factors, conversion rules and spatial characteristics. Results: Urban construction land and paddy fields expanded to suitable areas on the original basis, and the forestry land with sparse distribution was reduced correspondingly due to development and utilization, while other land types did not change significantly in quantity and space. Conclusion: Urbanization construction and agricultural development can provide the foundation and support for the economic development of Kaishan Fengweihan city. At the same time, it is necessary to give consideration to ecological protection and promote the overall, coordinated and sustainable use of land resources.

It has been found that the non-B form DNA structures, like G-quadruplex (G4) and i-motif, are involved in many important biological processes. Our previous study showed that the silkworm transcription factor BmLARK binds to the G4 structure in the promoter of the transcription factor BmPOUM2 and regulates its promoter activity. However, the binding mechanism between BmLARK and BmPOUM2 G4 structure remains unclear. In this study, binding domains and key amino acid residues involved in the interaction between BmLARK and BmPOUM2 G4 were studied. The electrophoretic mobility shift assay results indicated that the two RNA-recognition motifs (RRM) of BmLARK are simultaneously required for the binding with the G4 structure. Either RRM1 or RRM2 alone could not bind with the G4 structure. The zinc-finger motif was not involved in the binding. A series of mutant proteins with specific amino acid mutations were expressed and used to identify the key amino acid residues involving the interaction. The results indicated that β sheets, especially the β1 and β3 sheets, in the RRM domains of BmLARK played critical roles in the binding with the G4 structure. Several amino acid mutations of RRM1/2 in ribonucleoprotein domain 1 (RNP1) (motif in β3 strand) and RNP2 (motif in β1 strand) caused loss of binding ability, indicating that these amino acids are the key sites for the binding. All the results suggest that RRM domains, particularly their the RNP1 and RNP2 motifs, play important roles not only in RNA recognition, but also in the G4 structure binding.

Background A large number of in vitro experiments have confirmed that DNA molecules can form i-motif advanced structure when multiple cytosines exist in the sequence. However, whether these structures are present in vivo environment still lacks sufficient experimental evidence. Results In this paper, we report the in vivo visualization of i-motif structures in the nuclei and chromosomes of the testis of the invertebrate Bombyx mori using immunofluorescence staining with an antibody specifically recognizing the endogenous transcription factor BmILF, which binds i-motif structure with high specificity. The number of i-motif structures observed in the genome increased when the pH was changed from basic to acidic and decreased under treatment with an i-motif inhibitor, the porphyrin compound TMPyP4. The pH change affected the transcription of genes that contain i-motif sequences. Moreover, there were more i-motif structures observed in the testis cells in interphase than in any other cell cycle stage. Conclusions In this study, the i-motif structures in invertebrates were detected for the first time at the cell and organ levels. The formation of the structures depended on cell cycle and pH and affected gene expression.

Using Zhijiang City, Hubei Province as an example, this study constructed an ecological risk assessment model based on land use data from the three phases of 2000, 2010, and 2020. We then determined the ecological compensation priority sequence based on the ecosystem services value (ESV) and the economic status of the research area. The findings revealed that there was a significant spatial differentiation in ESV during the study period, with the ESV being higher south of the Yangtze River than north. Overall, in Zhijiang City, the ESV generally decreased over the course of the study period, with a decrease of CNY 812 million in 20 years. The loss of wetland and grassland was the greatest, and was most obvious between 2010 and 2020, whereas the loss of construction land was the lowest among the different types of landscapes. The ecological risk index of Zhijiang City showed a declining trend between 2000 and 2020. The extent of high-ecological risk areas shrank by 55.83 km2, and their predominant landscape types were grassland and forest land. The low-ecological risk area expanded by 340.50 km2 and was primarily distributed in construction land along the Yangtze River Basin. The ecological compensation priority sequence was divided into five levels in each town in Zhijiang City, with Gujiadian Town and Baiyang Town receiving the highest grades and being designated as priority compensation areas. The study intends to serve as a model for the construction of ecological cities, ecological environmental protection, and sustainable development in the Yangtze River Basin.

DNA secondary structure i-motif involves in gene transcription and considered as a novel target for cancer gene therapy. I-motif-binding compounds can either stabilize or destroy the structure, resulting in change in target gene transcription. In this study, a large-scale screening of binding compounds was conducted using the i-motif structure of BmPOUM2, a transcription factor in silkworm, Bombyx mori. Surface plasmon resonance imaging (SPRi) high-throughput binding screening of 3642 compounds found 60 compounds with an binding affinity Kd of 10−7-10−6 M. SPRi and circular dichroism (CD) double screening demonstrated that the BmPOUM2 i-motif structure bound the compounds IF1, IF3, IF4, IF6 and IF7 with Kd of 10−7 M, and the compounds IF2 and tetrakis (4-N-methylpyridyl) porphine (TMPyP4) with a Kd of 10−8 M. Interestingly, IF2, IF3, IF4, IF6 and IF7 promoted the binding of the i-motif-binding protein BmILF with the i-motif structure, whereas TMPyP4 inhibited the binding. This study provided a list of compounds that have potential applications in functional analysis of i-motif structure and in pesticide and drug development through gene transcription regulation by i-motif structure.

Neuromyelitis optica spectrum disorder (NMOSD) may sometimes be misdiagnosed as multiple sclerosis (MS) because both disorders have similar clinical presentations and commonly show white matter damage in the brain. Diffusion tensor imaging (DTI) is an advanced MRI technique to assess the microstructural organization of white matter and provides greater pathological specificity than conventional MRI. In the present combined cross-sectional and longitudinal study, the novel DTI technique of Track-Based Spatial Statistics (TBSS) was used to investigate the difference of DTI parameter abnormalities between NMOSD and MS.A total of 42 patients with NMOSD, 51 patients with MS and 56 health controls (HC) were recruited and of these 14 patients with NMOSD and 13 patients with MS were also studied at follow-up after an average interval of approximately one year. Measurements of fractional anisotropy (FA), mean diffusion (MD), axial diffusivity (AD) and radial diffusivity (RD) were compared at baseline and follow-up in patients with NMOSD and MS.Significant reduction in FA, increase in MD, AD and RD were observed in patients with MS (p0.05) and reduced FA was shown in NMOSD (p0.05) compared to HC, with all the effects, together with lesion load on T1WI and T2WI, being greater in patients with MS than in patients with NMOSD (p0.05). There was no significant difference in the time interval to follow-up in patients with MS (1.37 years) and NMOSD (1.25 years) (p0.05), during which there were significant changes in EDSS score between baseline and follow-up in NMOSD and MS patients (p0.05). There was a significantly reduced FA, and increased MD and RD in patients with MS (p0.05), but no significant changes in patients with NMOSD (p0.05).Both MS and NMOSD have microstructure damage in white matter, while the progressive change in brain microstructural properties is observed in patients with MS but may not in patients with NMOSD in a short-term follow-up.

Background: The volume change of multiple sclerosis (MS) lesion is related to its activity and can be used to assess disease progression. Therefore, the purpose of this study was to develop radiomics models for predicting the evolution of unenhanced MS lesions by using different kinds of machine learning algorithms and explore the optimal model. Methods: In this prospective observation, 45 follow-up MR images obtained in 36 patients with MS (mean age 32.53±10.91; 23 women, 13 men) were evaluated. The lesions will be defined as interval activity and interval inactivity, respectively, based on the percentage of enlargement or reduction of the lesion >20% in the follow-up MR images. We extracted radiomic features of lesions on FLAIR images, and used recursive feature elimination (RFE), ReliefF algorithm and least absolute shrinkage and selection operator (LASSO) for feature selection, then three classification models including logistic regression, random forest and support vector machine (SVM) were used to build predictive models. The performance of the models were evaluated based on the sensitivity, specificity, precision, negative predictive value (NPV) and receiver operating characteristic curve (ROC) curves analyses. Results: 135 interval inactivity lesions and 110 interval activity lesions were registered in our study. A total of 972 radiomics features were extracted, of which 265 were robust. The consistency and effectiveness of model performance were compared and verified by different combinations of feature selection and machine learning methods in different K-fold cross-validation strategies where K ranges from 5 to 10, thus demonstrating the stability and robustness. SVM classifier with ReliefF algorithm had the best prediction performance with an average accuracy of 0.827, sensitivity of 0.809, specificity of 0.841, precision of 0.921, NPV of 0.948 and the areas under the ROC curves (AUC) of 0.857 (95% CI: 0.812–0.902) in the cohorts. Conclusion: The results demonstrated that the radiomics-based machine learning model has potential in predicting the evolution of MS lesions.

Summary DNA methylation is an important epigenetic modification. However, the regulations and functions of insect intragenic DNA methylation remain unknown. Here, we demonstrate that a regulatory mechanism involving intragenic DNA methylation controls ovarian and embryonic developmental processes in Bombyx mori. In B. mori, DNA methylation is found near the transcription start site (TSS) of ovarian genes. By promoter activity analysis, we observed that 5′ UTR methylation enhances gene expression. Moreover, methyl-DNA-binding domain protein 2/3 (MBD2/3) binds to the intragenic methyl-CpG fragment and recruits acetyltransferase Tip60 to promote histone H3K27 acetylation and gene expression. Additionally, genome-wide analyses showed that the peak of H3K27 acetylation appears near the TSS of methyl-modified genes, and DNA methylation is enriched in genes involved in protein synthesis in the B. mori ovary, with MBD2/3 knockdown resulting in decreased fecundity. These data uncover a mechanism of gene body methylation for regulating insect gene expression and reproduction., Graphical Abstract, Highlights • Insect intragenic 5mC enhances gene expression through histone H3K27 acetylation • MBD2/3 binds the intragenic 5mC and recruits Tip60 to promote H3K27 acetylation • Intragenic 5mCs modify protein synthesis-related genes in insect ovaries • The intragenic 5mC plays a role in insect reproduction, Entomology; molecular mechanism of gene regulation; omics

An optimal sensor placement of a precipitation station network should fulfill different regulations and requirements, such as coverage maximization, easy access, and uniform distribution. H...

Knowing the distinction between benign and borderline/malignant phyllodes tumors (PTs) can help in the surgical treatment course. Herein, we investigated the value of magnetic resonance imaging-based texture analysis (MRI-TA) in differentiating between benign and borderline/malignant PTs.Forty-three women with 44 histologically proven PTs underwent breast MRI before surgery and were classified into benign (n = 26) and borderline/malignant groups (n = 18 [15 borderline, 3 malignant]). Clinical and routine MRI parameters (CRMP) and MRI-TA were used to distinguish benign from borderline/malignant PT. In total, 298 texture parameters were extracted from fat-suppression (FS) T2-weighted, FS unenhanced T1-weighted, and FS first-enhanced T1-weighted sequences. To evaluate the diagnostic performance, receiver operating characteristic curve analysis was performed for the K-nearest neighbor classifier trained with significantly different parameters of CRMP, MRI sequence-based TA, and the combination strategy.Compared with benign PTs, borderline/malignant ones presented a higher local recurrence (MRI-TA demonstrated good predictive performance for breast PT pathological grading and could provide surgical planning guidance. Clinical data and routine MRI features were also valuable for grading PTs.

DNA methylation is an important epigenetic modification. DNA methyltransferases (Dnmts), which catalyze the formation of 5-methylcytosine, play a role in ovarian and embryonic development in some insects. However, the underlying mechanism of Dnmt in mediating ovarian and embryonic development remains unclear. In this study, the regulation and function of Bombyx mori Dnmt1 were investigated. By progressively deleting the sequence upstream of Dnmt1, a region located between -580 and -560 region from the transcription initiation site was found to have the most transcriptional activity. Electrophoretic mobility shift assay and chromatin immunoprecipitation demonstrated that transcription factor Y box binding protein (YBP), a homolog of human Y box binding protein 1 (YBX1), bound to the -580 to -560 region. YBP knockdown and overexpression in a Bombyx cell line indicated that YBP activates Dnmt1 expression. Furthermore, GST-pulldown and co-immunoprecipitation demonstrated that YBP and ovarian CCAAT/enhancer binding protein (C/EBPg) could bind each other. Simultaneous knockdown of C/EBPg and YBP was more effective than single-gene RNAi in inhibiting Dnmt1 expression and reducing the hatching rate. These results demonstrated that the interaction of C/EBPg and YBP activated Dnmt1 expression. Correlated with the expression profiles of the studies genes, our results suggest that high-level expression and interaction of C/EBPg and YBP in ovaries and embryos enhance the expression of Dnmt1, thus ensuring high reproduction rate in B. mori.

The two major rainfall observation techniques, ground-based measurements and remote sensing, have distinct coverage characteristics. Large-scale spatial coverage and long-term temporal coverage cannot be achieved simultaneously by using only ground-based precipitation stations or space-borne sensors. Given the temporal discontinuity of satellite coverage and limited ground-based observation resources, we propose a method for siting precipitation stations in conjunction with satellite-based rainfall sensors to maximize the total spatial-temporal coverage of weighted demand in a continuous observation period. Considering the special principles of deploying precipitation stations and the requirement for continuous coverage in space and time, a time-continuous maximal covering location problem (TMCLP) model is introduced. The maximal spatial coverage range of a precipitation station is determined based on the minimum density required and the site-specific terrain conditions. The coverage of a satellite sensor is calculated for each time period when it passes overhead. The polygon intersection point set (PIPS) is refined to identify finite candidate sites. By narrowing the continuous search space to a finite dominating set and discretizing the continuous observation period to sequential sub-periods, the siting problem is solved using the TMCLP model and refined PIPS. According to specific monitoring purposes, different weighting schemes can be used to evaluate the coverage priority of each demand object. The Jinsha River Basin is selected as the study region to test the proposed method. Satellite-borne precipitation radar is used to evaluate the satellite coverage. The results show that the proposed method is effective for precipitation station configuration optimization, and the model solution achieves higher coverage than the real-world deployment. The applicability of the proposed method, site selection criteria, deployment strategies in different observation modes, and the impacts of different weighting schemes are also discussed.

Double-stranded DNAs are usually present in the form of linear B-form double-helix with the base pairs of adenine (A) and thymine (T) or cytosine (C) and guanine (G), but G-rich DNA can form four-stranded G-quadruplex (G4) structures, which plays important roles in transcription, replication, translation and protection of telomeres. In this study, a RNA recognition motif (RRM)-containing protein, BmLARK, was identified and demonstrated to bind G4 structures in the promoters of a transcription factor BmPOUM2 and other three unidentified genes of Bombyx mori, as well as three well-defined G4 structures in the human genes. Homologous LARKs from Bombyx mori, Drosophila melanogaster, Mus musculus and Homo sapiens bound G4 structures in BmPOUM2 and other genes in B. mori and H. sapiens. Upon binding, LARK facilitated the formation and stability of the G4 structure, enhancing the transcription of target genes. The G4 structure was visualized in vivo in cells and testis from invertebrate B. mori and vertebrate Chinese hamster ovary (CHO) cells. The results of this study strongly suggest that LARK is a novel and conserved G4-binding protein and that the G4 structure may have developed into an elaborate epigenetic mechanism of gene transcription regulation during evolution.

Solar radiation plays important roles in energy application, vegetation growth and climate change. Empirical relations and machine-learning methods have been widely used to estimate global solar radiation (GSR) in recent years. An artificial neural network (ANN) based on spatial interpolation is developed to estimate GSR in southeast China. The improved Bristow–Campbell (IBC) model and the improved Angstrom–Prescott (IA–P) model are compared with the ANN model to explore the best model in solar radiation modeling. Daily meteorological parameters, such as sunshine duration hours, mean temperature, maximum temperature, minimum temperature, relative humidity, precipitation, air pressure, water vapor pressure, and wind speed, along with station-measured GSR and a daily surface GSR dataset over China obtained from the Data Assimilation and Modeling Center for Tibetan Multi-spheres (DAM), are used to predict GSR and to validate the models in this work. The ANN model with the network of 9-17-1 provides better accuracy than the two improved empirical models in GSR estimation. The root-mean-square error (RMSE), mean bias error (MBE), and determination coefficient ( R 2 ) are 2.65 MJ m −2 , −0.94 MJ m −2 , and 0.68 in the IA−P model; 2.19 MJ m −2 , 1.11 MJ m −2 , and 0.83 in the IBC model; 1.34 MJ m −2 , −0.11 MJ m −2 , and 0.91 in the ANN model, respectively. The regional monthly mean GSR in the measured dataset, DAM dataset, and ANN model is analyzed. The RMSE (RMSE %) is 1.07 MJ m −2 (8.91%) and the MBE (MBE %) is −0.62 MJ m −2 (−5.21%) between the measured and ANN-estimated GSR. The statistical errors of RMSE (RMSE %) are 0.91 MJ m −2 (7.28%) and those of MBE (MBE %) are −0.15 MJ m −2 (−1.20%) between DAM and ANN-modeled GSR. The correlation coefficients and R 2 are larger than 0.95. The regional mean GSR is 12.58 MJ m −2 . The lowest GSR is observed in the northwest area, and it increases from northwest to southeast. The annual mean GSR decreases by 0.02 MJ m −2 decade −1 over the entire southeast China. The GSR in 52 stations experiences a decreasing trend, and 21% of the stations are significant at the 95% level.

Traditional location problems usually focus on spatial and temporal impacts of facilities, but few studies have focused on sensor siting under satellite-borne monitoring in a space-ground integrated sensor network. Given the partial coverage and the requirement for continuous coverage in space and time, a time-weighted maximal covering location problem with partial coverage (TMCLP-PC) model is introduced. This model is solved using a modified genetic algorithm (GA)-based approach that utilizes the spatio-temporal characteristics of potential facility sites for faster convergence. The performance of the new GA is tested on a precipitation station siting problem in the Jinsha River Basin on the upper reaches of the Yangtze River in China. The results demonstrate that the proposed GA can significantly reduce the computation time compared with CPLEX, a commercial integer programming solver, and can outperform the greedy algorithm and the GAs with one-point, two-point, fusion, and uniform crossover operators. The applicability of the proposed method and exploration of the design in the new GA are also discussed.

A bibliometric analysis of published geographical information system (GIS) research was performed to evaluate current research trends, quantitatively and qualitatively, over the period 1961---2010, based on SCIE & SSCI databases. Articles referring to GIS were concentrated on the analysis of scientific outputs, distribution of subject categories, source journals, international collaboration, geographic distribution of authors, temporal trends in keywords usage, and the relationship between GIS articles and computer numbers. The results showed that the growth of scientific outputs has exploded since 1991, with an increasing collaboration index, references, and citations. Environmental sciences, multidisciplinary geosciences, ecology, physical geography, water resources, geography, and remote sensing were most frequently used subject categories, and IJGIS was the most productive journal in this field. The United States produced the most independent and collaborative articles, took a central position in the collaboration network, and had the greatest number of most prolific institutions. North America, Western Europe, and East Asia had major clusters of authors. A keywords analysis demonstrated that the integration of GIS and RS was a key development trend. Spatial analysis, model, land use, map, and landscape were research hotspots. Generally, GIS research was significantly correlated with the development of personal computers, and there was a statistically significant quadratic polynomial growth in GIS-related articles. This study will help readers to understand global trends in GIS research during the past 50 years.

Three metal-free porphyrins modified with Boc-l-threonine and their zinc analogs were synthesized and characterized by elemental analysis, 1H NMR, UV/vis, and fluorescence spectroscopies. The binding of imidazole derivatives to these zinc porphyrins was studied, with emphasis on the binding mechanism in CH2Cl2 solution, by means of UV/vis spectroscopy and quantum chemical methods. Both experimental results and theoretical calculations showed that a coordination reaction occurred between the zinc porphyrins and imidazole derivatives. The association constants between the zinc porphyrins and imidazole derivatives decreased in the order N-MeIm>Im. Increasing the temperature disfavored the interaction. Thermodynamic parameters calculated by the van't Hoff equation showed that the driving force for the reaction was the enthalpy change. The fluorescence changes associated with the interaction between the zinc porphyrins and imidazole derivatives were also studied by fluorescence spectroscopy. The experimental results showed significant quenching between the various zinc porphyrins and imidazole derivatives.