Weighted Correlation Analysis Research Articles

Structural optimisation algorithm of weight correlation analysis for DBN

The deep belief network (DBN) algorithm has slow convergence rate and low learning efficiency, and it is sensitive to model hyper-parameters. In view of the fact that DBN is a learning network model with a large number of network nodes and multiple hidden layers, this paper proposes a weight correlation analysis algorithm for DBN (WCA-DBN) to determine the approximately optimal network structure of DBN. This algorithm establishes a PS orthogonal projection space based on the 'arbitrary node set' using the linear discriminant analysis (LDA) method, projects the 'balanced node set' onto the PS plane, and solves the weights of the network nodes between sets through the correlation principle, to adjust the network structure of the hidden layer adaptively. The real-time traffic flow of six different types of roads in Jinan City, Shandong Province was selected as experimental materials to verify that the WCA-DBN algorithm has more obvious advantages over traditional algorithms in terms of accuracy and time complexity.

The spatial and temporal dimensions of the interdependence between the airline industry and the Chinese economy

The airline industry contributes largely to the economic development of a region. At the same time, the fortunes of the industry can also be affected by regional economic change. This paper uses geographically weighted correlation analysis to investigate the spatial heterogeneity and temporal change of this interdependence as seen in China over the years from 2005 to 2016. The results show that the interdependence between the airline industry and provincial economies is non-stationary, generally with a spatial variation along the east-west axis across China's provinces. Further, the temporal change in the interdependence was affected by specific economic changes, such as the global crisis of 2008, when it weakened. Specifically, air passenger activities in the eastern provinces were more sensitive to some economic changes of 2012, while air freight activities in the western and central provinces were more sensitive to the global economic crisis of 2008. The size of urban agglomeration and regional GDP also influence the spatial heterogeneity of this interdependence with weaker links as GDP increases. It is possible that liberalization of the airline industry could enhance the interdependence in advanced regions. Thus, our results provide significant policy implications for a joint focus on the development of the regional economy and the airline industry.

Using Dual-Polarization Interferograms to Correct Atmospheric Effects for InSAR Topographic Mapping

Atmospheric effect represents one of the major error sources for interferometric synthetic aperture radar (InSAR), particularly for the repeat-pass InSAR data. In order to further improve the practicability of InSAR technology, it is essential to study how to estimate and eliminate the undesired impact of atmospheric effects. In this paper, we propose the multi-resolution weighted correlation analysis (MRWCA) method between the dual-polarization InSAR data to estimate and correct atmospheric effects for InSAR topographic mapping. The study is based on the a priori knowledge that atmospheric effects is independent of the polarization. To find the identical atmospheric phase (ATP) signals of interferograms in different polarizations, we need to remove the other same or similar phase components. Using two different topographic data, differential interferometry was firstly performed so that the obtained differential interferograms (D-Infs) have different topographic error phases. A polynomial fitting method is then used to remove the orbit error phases. Thus, the ATP signals are the only identical components in the final obtained D-Infs. By using a forward wavelet transform, we break down the obtained D-Infs into building blocks based on their frequency properties. We then applied weighted correlation analysis to estimate the wavelet coefficients attributed to the atmospheric effects. Thus, the ATP signals can be obtained by the refined wavelet coefficients during inverse wavelet transform (IWT). Lastly, we tested the proposed method by the L-band Advanced Land Observing Satellite (ALOS)-1 PALSAR dual-polarization SAR data pairs covering the San Francisco (USA) and Moron (Mongolia) regions. By using Ice, Cloud, and land Elevation Satellite (ICESat) data as the reference data, we evaluated the vertical accuracy of the InSAR digital elevation models (DEMs) with and without atmospheric effects correction, which shows that, for the San Francisco test site, the corrected interferogram could provide a DEM with a root-mean-square error (RMSE) of 7.79 m, which is an improvement of 40.5% with respect to the DEM without atmospheric effects correction. For the Moron test site, the corrected interferogram could provide a DEM with an RMSE of 10.74 m, which is an improvement of 30.2% with respect to the DEM without atmospheric effects correction.

Isolation of stem cell populations from wharton's jelly sections of umbilical cord and comparison analysis with cord blood stem cells

Wharton’s jelly (WJ) is a gelatinous tissue exists in the umbilical cord contains stromal cells, termed as mesenchymal stromal cells (MSCs). Current study designed to characterize the stem cell population both within the cord blood and it’s wharton’s jelly tissue and it’s correlation to neonatal parameters. Both wharton’s jelly and cord blood and their CD34+ and CD90+ expression was enumerated by flow-cytometry. Neonatal parameters along with the mode of delivery were analyzed to correlate with CD34 and CD90 markers. From a total of 20 deliveries, CD34 and CD90 expression pattern showed varied in both samples. Gender and the expression of CD34 and CD90 markers doesn’t show any significant change. Whereas, correlation analysis of weight with CD34+ and CD90+ cell counts showed significant difference and it may have the effect on both cell counts. Neonatal parameters especially birth weight may have the effect on cell count of CD34 and CD90 in both CB and WJ. Current study provide a fast method for mesenchymal cell isolation from Wharton’s jelly tissue using the total length of the cord, which may be easily applied along with the UC blood, for the banking of UC.

Screening of the prognostic targets for breast cancer based co-expression modules analysis.

The purpose of the present study was to screen the prognostic targets for breast cancer based on a co-expression modules analysis. The microarray dataset GSE73383 was downloaded from the Gene Expression Omnibus (GEO) database, including 15 breast cancer samples with good prognosis and 9 breast cancer samples with poor prognosis. The differentially expressed genes (DEGs) were identified with the limma package. The Database for Annotation, Visualization and Integrated Discovery was used to perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Furthermore, the co-expression analysis of DEGs was conducted with weighted correlation analysis. The interaction associations were analyzed with the Human Protein Reference Database and BioGRID. The protein-protein interactions (PPI) network was constructed and visualized by Cytoscape software. A total of 491 DEGs were identified in breast cancer samples with poor prognosis compared with those with good prognosis, and they were enriched in 85 GO terms and 4 KEGG pathways. 368 DEGs were co-expressed with others, and they were clustered into 10 modules. Module 6 was the most relevant to the clinical features, and 21 genes and 273 interaction pairs were selected out. Abnormal expression levels of required for meiotic nuclear division 5 homolog A (RMND5A) and angiopoietin-like protein 1 (ANGPTL1) were associated with a poor prognosis. It was indicated that SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily D, member 1, SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily D, member 1, dihydropyrimidinase-like 2, RMND5A and ANGPTL1 were potential prognostic markers in breast cancer, and the cell cycle may be involved in the regulation of breast cancer.

Ligand Binding Constants to Lithium Hexamethyldisilazide Determined by Diffusion-Ordered NMR Spectroscopy.

We report the direct measurement of ligand-binding constants of organolithium complexes using a 1H NMR/diffusion-ordered NMR spectroscopy (DOSY) titration technique. Lithium hexamethyldisilazide complexes with ethereal and ester donor ligands (THF, diethyl ether, MTBE, THP, tert-butyl acetate) are characterized using 1H NMR and X-ray crystallography. Their aggregation and solvation states are confirmed using diffusion coefficient-formula weight correlation analysis, and the 1H NMR/DOSY titration technique is applied to obtain their binding constants. Our work suggests that steric hindrance of ethereal ligands plays an important role in the aggregation, solvation, and reactivity of these complexes. It is noteworthy that diffusion methodology is utilized to obtain binding constants.

“Fibrous nests” in human hepatocellular carcinoma express a Wnt-induced gene signature associated with poor clinical outcome

Hepatocellular carcinoma (HCC) is the 3rd cause of cancer-related death worldwide. Most cases arise in a background of chronic inflammation, extracellular matrix (ECM) remodeling, severe fibrosis and stem/progenitor cell amplification. Although HCCs are soft cellular tumors, they may contain fibrous nests within the tumor mass. Thus, the aim of this study was to explore cancer cell phenotypes in fibrous nests. Combined anatomic pathology, tissue microarray and real-time PCR analyses revealed that HCCs (n=82) containing fibrous nests were poorly differentiated, expressed Wnt pathway components and target genes, as well as markers of stem/progenitor cells, such as CD44, LGR5 and SOX9. Consistently, in severe liver fibroses (n=66) and in HCCs containing fibrous nests, weighted correlation analysis revealed a gene network including the myofibroblast marker ACTA2, the basement membrane components COL4A1 and LAMC1, the Wnt pathway members FZD1; FZD7; WNT2; LEF1; DKK1 and the Secreted Frizzled Related Proteins (SFRPs) 1; 2 and 5. Moreover, unbiased random survival forest analysis of a transcriptomic dataset of 247 HCC patients revealed high DKK1, COL4A1, SFRP1 and LAMC1 to be associated with advanced tumor staging as well as with bad overall and disease-free survival. In vitro, these genes were upregulated in liver cancer stem/progenitor cells upon Wnt-induced mesenchymal commitment and myofibroblast differentiation. In conclusion, fibrous nests express Wnt target genes, as well as markers of cancer stem cells and mesenchymal commitment. Fibrous nests embody the specific microenvironment of the cancer stem cell niche and can be detected by routine anatomic pathology analyses.

A correlation analysis of Broselow™ Pediatric Emergency Tape-determined pediatric weight with actual pediatric weight in India.

The Broselow™ Pediatric Emergency Tape indicates standardized, pre-calculated medication doses, dose delivery volumes, and equipment sizes using color-coded zones based on height-weight correlations. The present study attempted to provide more evidence on the effectiveness of the Broselow™ Pediatric Emergency Tape by comparing the tape-estimated weights with actual weights. We hypothesized that the Broselow™ Pediatric Emergency Tape would overestimate weights in Indian children aged<10 years, leading to inaccurate dosing and equipment sizing in the emergency setting. This prospective study of pediatric patients aged <10 years who were divided into three groups based on actual body weight: <10 kg, 10-18 kg, and >18 kg. We calculated the percentage difference between the Broselow-predicted weight and the measured weight as a measure of tape bias. Concordant results were those with a mean percent difference within 3%. Standard deviation was measured to determine precision. Accuracy was determined as color-coded zone prediction and measured weight concordance, including the percentage overestimation by 1-2 zones. The male-to-female ratio of the patients was 1.3:1. Total agreement between color-coding was 63.18% (κ=0.582). The Broselow™ color-coded zone agreement was 74.8% in the <10 kg group, 61.24% in the 10-18 kg group, and 53.42% in the >18 kg group. The Broselow™ Pediatric Emergency Tape showed good evidence for being more reliable in children of the <10 kg and 10-18 kg groups. However, as pediatric weight increased, predictive reliability decreased. This raises concerns over the use of the Broselow™ Pediatric Emergency Tape in Indian children because body weight was overestimated in those weighing >18 kg.

A comparison analysis of environmental factors affecting software reliability

Fifteen years ago, Zhang and Pham launched a survey to investigate the impact of software development environmental factors (EFs) on software reliability assessment. Software development has gone through substantial changes during the past fifteen years. How different the environmental factors have become? This paper aims to revisit the 32 environmental factors and analyze their impact on software development and reliability based on a current survey to software development practitioners. The participants of this study come from 20 various organizations and they hold different positions and work on different application areas. Statistical analysis method, such as principle component analysis, relative weighted method, Tukey method, backward elimination, and correlation analysis are applied to analyze these factors. We compare the findings in the two studies and list the most significant factors based on the general ranking and the principle components. The environmental factors in each development phase are also studied. Recommendations such as time allocation during software development process are also made.

Correlation and path coefficient analysis of body weight and morphometric traits of two exotic genetic groups of ducks in Nigeria

The study aimed at describing objectively the interdependence between body weight (BWT) and morphometric traits in Khaki Campbell and Pekin ducks using multivariate path analysis technique. Measurements were taken on one hundred and ninety seven (197) randomly selected 10-week old Khaki Campbell and Pekin ducks, respectively in Plateau State, Nigeria. The birds were reared on deep litter in a semi-intensive system where they were kept in a fenced area provided with water ponds and locked up in the poultry house during the night. The body parts measured were, body length (BDL); thigh length (THL); thigh circumference (THC); breast circumference (BTC); bill length (BLL); neck length (NKL); neck circumference (NKC); shank length (SHL); shank width (SHW); total leg length (TLL) and wing length (WL). General linear model was used to study genotype and sex effects. Pekin ducks had a superior advantage (p&lt;0.05) over their Khaki Campbell counterparts in all the body parameters estimated. Sexual dimorphism (p&lt;0.05) was in favour of male ducks. Pairwise phenotypic correlations between BWT and morphometric traits were positive and significant (p&lt;0.01), ranging from 0.38-0.95 and 0.35-0.92 for Khaki Campbell and Pekin ducks, respectively. Path analysis revealed that BDL was the variable of utmost importance directly influencing BWT in male Khaki Campbell and Pekin ducks (path coefficient=0.535 and 0.508, respectively; p&lt;0.01) while BTC and SHL were the most responsible parameters affecting BWT in female Khaki Campbell and Pekin ducks [path coefficient=0.594 (P&lt;0.01) and 1.197 (p&lt;0.05), respectively]. The optimum regression models for the prediction of BWT in Khaki Campbell ducks included BDL, SHL, BTC and NKC (male) and BDL, WNL and BTC (female); while in their Pekin counterparts, BDL, BLL and BTC (male) and BDL and SHL (female) were incorporated.DOI: http://dx.doi.org/10.3329/bjas.v44i1.23112 Bang. J. Anim. Sci. 2014. 44 (1): 1-9

Ancestry dependent DNA methylation and influence of maternal nutrition.

There is extensive variation in DNA methylation between individuals and ethnic groups. These differences arise from a combination of genetic and non-genetic influences and potential modifiers include nutritional cues, early life experience, and social and physical environments. Here we compare genome-wide DNA methylation in neonatal cord blood from African American (AA; N = 112) and European American (EA; N = 91) participants of the CANDLE Study (Conditions Affecting Neurocognitive Development and Learning in Early Childhood). Our goal is to determine if there are replicable ancestry-specific methylation patterns that may implicate risk factors for diseases that have differential prevalence between populations. To identify the most robust ancestry-specific CpG sites, we replicate our results in lymphoblastoid cell lines from Yoruba African and CEPH European panels of HapMap. We also evaluate the influence of maternal nutrition—specifically, plasma levels of vitamin D and folate during pregnancy—on methylation in newborns. We define stable ancestry-dependent methylation of genes that include tumor suppressors and cell cycle regulators (e.g., APC, BRCA1, MCC). Overall, there is lower global methylation in African ancestral groups. Plasma levels of 25-hydroxy vitamin D are also considerably lower among AA mothers and about 60% of AA and 40% of EA mothers have concentrations below 20 ng/ml. Using a weighted correlation analysis, we define a network of CpG sites that is jointly modulated by ancestry and maternal vitamin D. Our results show that differences in DNA methylation patterns are remarkably stable and maternal micronutrients can exert an influence on the child epigenome.

Energy expenditure measurement of various physical activity and correlation analysis of body weight and energy expenditure in elementary school children

Purpose: There is a lack of data on the energy cost of childrens everyday activities, adult values are often used as surrogates. In addition, the influence of body weight on the energy cost of activity when expressed as metabolic equivalents (METs) has not been vigorously explored. Methods: In this study 20 elementary school students 9~12 years of age completed 18 various physical activities while energy expenditure was measured continuously using a portable telemetry gas exchange system (K₄b², Cosmed, Rome, Italy). Results: The average age was 10.4 years and the average height and weight was 145.1 ㎝ and 43.6 ㎏, respectively. Oxygen consumption (VO₂), energy expenditure and METs at the time of resting of the subjects were 5.41 mL/㎏/min, 1.44 ㎉/㎏/h, and 1.5 METs, respectively. METs values by 18 physical activities were as follows: Homework and reading books (1.6 METs), playing game with a mobile phone or video while sitting (1.6 METs), watching TV while sitting on a comfortable chair (1.7 METs), playing video game or mobile phone game while standing (1.9 METs), sweeping a room with a broom (2.7 METs) and playing a board game (2.8 METs) belong to light intensity physical activities. By contrary, speedy walking and running were 6.6 and 6.7 METs, respectively, which belong to high intensity physical activities over 6.0 METs. When the effect of body weight on physical activity energy expenditure was determined, R² values increased with 0.116 (playing a game at sitting), 0.176 (climbing up and down stairs), 0.246 (slow walking), and 0.455 (running), which showed that higher activity intensity increased explanation power of body weight on METs value. Conclusion: This study is important for direct evaluation of energy expenditure by physical activities of children, and it could be used directly for revising and complementing the existing activity classification table to fit for children.

Chiral lithium diamides derived from linked N-isopropyl valinol or alaninol.

Four different chiral diamino diethers synthesized from N-isopropyl valinol or N-isopropyl alaninol were lithiated with n-butyllithium in tetrahydrofuran or diethyl ether. Crystal structures of the dilithiated diamino diethers were determined by X-ray diffraction. Three dilithiated diamino diethers including (2S,2'S)-1,1'-(butane-1,4-diylbis(oxy))bis(N-isopropylpropan-2-amine) 7, (2S,2'S)-1,1'-(pentane-1,5-diylbis(oxy))bis(N-isopropylpropan-2-amine) 8, and (2S,2'S)-1,1'-(heptane-1,7-diylbis(oxy))bis(N-isopropyl-3-methylbutan-2-amine) 9 are dimers, whereas dilithiated (2S,2'S)-1,1'-(pentane-1,5-diylbis(oxy))bis(N-isopropyl-3-methylbutan-2-amine) 10 is a monomer. The lithium atoms in all crystal structures adopt a nonequivalent coordination protocol and exist in two different environments in which one of the lithium atoms is tetra-coordinated while the other one is tri-coordinated. The solution structures of the dilithiated diamino diethers are also characterized by a variety of NMR experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion coefficient-formula (D-FW) weight correlation analyses and other one- and two-dimensional NMR techniques.

Influence of Steric Factors on Chiral Lithium Amide Aggregates

The solution structures of three mixed aggregates dissolved in toluene-d8 consisting of the lithiated amides derived from (S)-N-isopropyl-1-((triisopropylsilyl)oxy)propan-2-amine, (R)-N-(1-phenyl-2-((triisopropylsilyl)oxy)ethyl)propan-2-amine, or (S)-N-isobutyl-3-methyl-1-((triisopropylsilyl)oxy)butan-2-amine and n-butyllithium are characterized by various NMR experiments including diffusion-ordered NMR spectroscopy with diffusion coefficient-formula weight correlation analyses (D-FW) and other one- and two-dimensional NMR techniques. We report that steric hindrance of R1 and R2 groups of the chiral lithium amide controls the aggregation state of the mixed aggregates. With a less hindered R2 group, lithium (S)-N-isopropyl-1-((triisopropylsilyl)oxy)propan-2-amide forms mostly a 2:2 ladder-type mixed aggregate with n-butyllithium. Increase of steric hindrance of the R1 and R2 groups suppresses the formation of the 2:2 mixed aggregate and promotes formation of a 2:1 mixed aggregate. We observe that lithium (S)-N-isobutyl-3-methyl-1-((triisopropylsilyl)oxy)butan-2-amide forms both a 2:2 mixed aggregate and a 2:1 mixed trimer with n-butyllithium. Further increase in the steric hindrance of R1 and R2 groups results in the formation of only 2:1 mixed aggregate as observed with lithium (R)-N-(1-phenyl-2-((triisopropylsilyl)oxy)ethyl)propan-2-amide.

Genome-wide transcriptional analysis of T cell activation reveals differential gene expression associated with psoriasis

BackgroundPsoriasis is a chronic autoimmune disease in which T cells have a predominant role in initiating and perpetuating the chronic inflammation in skin. However, the mechanisms that regulate T cell activation in psoriasis are still incompletely understood. The objective of the present study was to characterize the main genetic pathways associated with T cell activation in psoriasis.ResultsGene expression profiles from in vitro activated T cells were obtained from 17 psoriasis patients and 7 healthy controls using Illumina HT-12 v4 microarrays. From a total of 47,321 analyzed transcripts, 42 genes were found to be differentially expressed between psoriasis and controls (FDR p-value < 0.1, absolute fold-change > 1.2). Using an independent cohort of 8 patients and 8 healthy controls we validated the overexpression of SPATS2L (p-value =0.0009) and KLF6 (p-value =0.0012) genes in activated T cells from psoriasis patients. Using weighted correlation analysis we identified SPATS2L and KLF6 coexpression networks, which were also significantly associated with psoriasis (p-value < 0.05). Gene Ontology analysis allowed the identification of several biological processes associated with each coexpression network. Finally, using Gene Set Enrichment Analysis over the global T cell transcriptome we also found additional genetic pathways strongly associated with psoriasis (p-value < 0.0001).ConclusionsThis study has identified two new genes, SPATS2L and KLF6, strongly associated with T cell activation in psoriasis. Functional analyses of the gene expression profiles also revealed new biological processes and genetic pathways associated with psoriasis. The results of this study provide an important insight into the biology of this common chronic inflammatory disease.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-14-825) contains supplementary material, which is available to authorized users.

Mixed Aggregates of an Alkyl Lithium Reagent and a Chiral Lithium Amide Derived from N-Ethyl-O-triisopropylsilyl Valinol

The crystal structure of a mixed aggregate containing lithiated (S)-N-ethyl-3-methyl-1-(triisopropylsilyloxy)butan-2-amine derived from (S)-valinol and cyclopentyllithium is determined by X-ray diffraction. The mixed aggregate adopts a ladder structure in the solid state. The ladder-type mixed aggregate is also the major species in a toluene-d8 solution containing an approximately 1:1 molar ratio of the lithiated chiral amide to cyclopentyllithium. A variety of NMR experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion coefficient-formula (D-FW) weight correlation analyses and other one- and two-dimensional NMR techniques allowed us to characterize the complex in solution. Solution state structures of the mixed aggregates of n-butyl, sec-butyllithium, isopropyllithium with lithiated (S)-N-ethyl-3-methyl-1-(triisopropylsilyloxy)butan-2-amine are also reported. Identical dimeric, ladder-type, mixed aggregates are the major species at a stoichiometric ratio of 1:1 lithium chiral amide to alkyllithium in toluene-d8 solution for all of the different alkyllithium reagents.

Characterization of Cyclopentyllithium and Cyclopentyllithium Tetrahydrofuran Complex

The solid-state structures of unsolvated, hexameric cyclopentyllithium and tetrameric cyclopentyllithium tetrahydrofuran solvate were determined by single-crystal X-ray diffraction. Cyclopentyllithium easily crystallized in hydrocarbon solvents. Solution-state structural analyses of cyclopentyllithium and cyclopentyllithium-tetrahydrofuran complexes in toluene-d8 were also carried out by diffusion-ordered NMR spectroscopy with diffusion coefficient-formula weight correlation analyses and other one- and two-dimensional NMR techniques. The solution-state studies suggest that unsolvated cyclopentyllithium exists as hexamer and tetramer equilibrating with each other. Upon solvation with tetrahydrofuran, cyclopentyllithium exists mostly as a tetrahydrofuran tetrasolvated tetramer.

Crystal Structure and Solution State Characterization of Lithium (S)-(1-(Bis(2-methoxyethyl)amino)-3-methylbutan-2-yl)(methyl)amide

The solid state structure of lithiated (S)-N(1),N(1)-bis(2-methoxyethyl)-N(2),3-dimethylbutane-1,2-diamine, which is a chiral amide base synthesized from (S)-valine was determined by single-crystal X-ray diffraction. The complex in solution state is also characterized by a variety of NMR experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion coefficient-formula weight correlation analyses and other one- and two-dimensional NMR techniques by dissolving the crystal in toluene-d8. The crystallography and NMR results suggest that the chiral amide is dimeric in both solid and solution states.

Correlation analysis of major morphometric traits and body weight of selective group at different month ages of Trachinotus ovatus

To investigate the effect of major morphometric traits of selective group of Trachinotus ovatus at different month ages on body weight,2 635 specimens at 1-month-old stage,4-month-old stage,7-month-old stage,10-month-old stage and 13-month-old stage were measured respectively in terms of total length(x1),body length(x2),body height(x3)and weight(y).Correlation coefficients,path coefficients and determination coefficients of each trait to body weight were calculated through path analysis and multiple linear regression.Effects of each morphometric trait on body weight were also dissected and then the optimal regression equation was established.The results showed that the correlations among 4 traits ranged from 0.017 to 0.960,and all reached significant level(P0.01)at different stages except that at 4-month-old stage.At 1-month-old stage and 4-month-old stage,the trait with strongest direct effect on body weight was the total length,but that at other stages was the body height.The result of determinant coefficient analysis was consistent with that of path analysis,and the fitness of equations at different stages was good(86.9%-90.6%).It indicated that the major morphometric traits affecting body weight were found and traits for selection should be considered at different stages,which provided technical parameters for selective breeding for T.ovatus.

Molecular Weight Determination and Correlation Analysis of Dalbergia sissoo Polysaccharide with Constituent Oligosaccharides

Mucilaginous polysaccharide extracted from Dalbergia sissoo Roxb. leaves has a number of medicinal applications. Molecular weight studies and correlation analysis of the structure of polysaccharide with oligosaccharides can be helpful for further utilisation, modification and structure-activity relationship for biological applications. To determine molecular weight of medicinally important polysaccharide. To establish an unequivocal correlation of the polysaccharide monosugars with constituting oligosaccharides and glucuronic acid content based on gas-liquid chromatography (GLC) with the spectrophotometric method. Complete and partial hydrolytic studies of pure polysaccharide yielded constituting monosugars and oligosaccharides. The ratio of sugars in polysaccharide and oligosaccharides was studied by preparation of alditol acetates and analysed using GLC. The uronic acid content was studied by GLC analysis and spectrophotometry. Molecular weight of the polysaccharide was determined using the viscometric method. Dalbergia sissoo leaves yielded 14.0% pure polysaccharide, containing 15.7% of glucuronic acid. Complete hydrolysis and GLC analysis of alditol acetate derivatives of reduced and unreduced monosugars indicated the presence of L-rhamnose, D-glucuronic acid, D-galactose and D-glucose in 1.00:1.00:2.00:2.33 molar ratios. Partial hydrolysis followed by monosugar analysis of oligosaccharides established the monosugar ratio in complete agreement with polysaccharide, thereby corroborating the sugar ratio. Similar uronic acid content was obtained by GLC and spectrophotometry. The polysaccharide had an average molecular weight of 1.5 × 10⁵ Da. The study has established an obvious correlation of the structure of polysaccharide with oligosaccharides, leading to unambiguous identification of monosaccharides, which normally is not studied conclusively while reporting the polysaccharide structure. The molecular weight of the polysaccharide was determined.