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Estimating the rainfall erosivity factor from monthly precipitation data in the Madrid Region (Spain)

entre l'érosion du sol par l'eau et les précipitations atmosphériques. [Relationship between soil erosion by water and rainfall]. Presses Universitaires de France, Paris. (In French.) Hudson, N., 1971. Soil Conservation. Cornell University Press, Ithaca. ICONA, 1988. Agresividad de la lluvia en España. Valores del factor R de la ecuación universal de pérdidas de suelo. [Rainfall erosivity in Spain. R-factor values for the Universal Soil Loss Equation]. Ministerio de Agricultura, Pesca y Alimentación, Madrid. (In Spanish

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Comparison of two methods of erosive rains determination

Abstract

Number of erosive rains, kinetic energy of erosive rains and factor of erosive efficiency of rains according to the USLE methodology were assessed by two methods of erosive rains determination. The first method (VAR1) defined erosive rains by intensity ≥ 0.4 mm· min-1; total ≥ 12.5 mm and the second method (VAR2) by intensity ≥ 6 mm· 15 min-1; total ≥ 12.5 mm. Database contained one minute precipitation data from four automatic stations in the Czech Republic for the period of 2000-2005. Two-way analysis of variance (ANOVA) showed a statistically highly significant difference between the annual number of erosive rains determined by the two methods. The rains simultaneously complying with two following criteria (30 min intensity lower than 15 mm·h−1 and sum of 40 mm) were not generally classified as erosive rains according to VAR2. The number of erosive rains determined by VAR2 most often reached 40 to 50% of VAR1 results. Two-way ANOVA proved highly significant differences between the kinetic energy values for the erosive rains determined by VAR1 a VAR2. According to VAR2 the rains with kinetic energy lower than 3 MJ·ha −1 are generally not considered as erosive rains. The results of kinetic energy of the erosive rains determined by VAR2 most often reached 60 to 70% of VAR1 results. Two-way ANOVA has not proved a statistical difference between annual values of R factor of erosive rains determined by the two methods. According to VAR2 the rains with R factor lower than 5 are in general not included into annual R factor value. The results of annual R factor values of erosive rains determined by VAR2 are about 25% lower than the results of VAR1. Correlation between number of erosive rains, kinetic energy of erosive rains and annual R factor value assessed by both methods showed a statistically significant relationship. The conversion formulas between results of the two methods (VAR1 and VAR2) were derived by linear regression. As conclusion we can state that when using present automatic stations in R factor analyses, we have to be aware of overestimating the erosivities compared to historical data based on ombrograms, where only low temporal resolution data were available.

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A sufficient condition for the existence of a k-factor excluding a given r-factor

{{\left( {2k - 1} \right)\left( {n - 1} \right)}}{{k\left( {n - 2} \right) + 3}} \end{array}$ . Then G has a k-factor . In this paper, we obtain a binding number condition for a graph to have a k -factor excluding a given r -factor, which is an extension of Theorems 1 , 2 , and 3 . The main result will be given in the following section. 2 Main Theorems In this section, we give our main results, which are the following theorems. Theorem 4 Let k and r be two nonnegative integers with k ≥ 2 , and let G be a graph of order n with n ≥ ( 2 k − 1 ) ( 2 k

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Values of rainfall erosivity factor for the Czech Republic

, M., 2004. Estimating the R-Factor from daily rainfall data in the sub-Mediterranean climate of southwest Slovenia. Hydrological Sciences - Journal - des Sciences Hydrologiques, 49, 5, 869-877. Rejman, J., Turski, R., Paluszek, J., 1998. Spatial and temporal variations in erodibility of less soil. Soil and Tillage Research, 46, 1-2, 61-68. Renard, K.G., Foster, G.R., Weesies, G.A., McCool, D.K., Yoder, D.C. 1997. Predicting Soil Erosion by Water: A Guid to Conservation Planning with the Revised Universal Soil Loss Equation (RUSLE

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Investigating the Effect of the Number of End-Panel Studs on the Seismic Properties of Cold-Formed Light-Steel Shear-Panel Braces

Abstract

Detailed investigation of the effect of the number of end-panel studs on the seismic properties of light-steel shear-panel braces in cold-formed steel frames and in particular the associated response modification coefficients (R) factor, are presented in this paper. A total of 6 full-scale 1200×2400 mm specimens are considered, and the responses investigated under a standard cyclic loading regime. Of particular interest are the specimens’ maximum lateral load capacity and deformation behavior as well as a rational estimation of the seismic response modification factor. The study also looks at the failure modes of the system and investigates the main factors contributing to the ductile response of the tested shear-panel braces in order to suggest improvements so that braces respond plastically with a significant drift and without any risk of brittle failure, such as connection failure or stud buckling.

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Comparing natural regeneration of Norway spruce Picea abies (L.) Karst. in the Kaszuby Lake District and in the other regions of northern Poland

Abstract

The paper investigates the biometric characteristics natural Norway spruce (Picea abies (L.) Karst.) regeneration in the Kaszuby Lake District, which is beyond the acknowledged Norway spruce range, with the natural regeneration in the Augustów Forest situated deep within the natural range, Warmia, at the edge of the natural range and in the West-Pomerania Lake District far beyond the natural range.

For each region, four tree stands with similar light conditions on the forest floor were selected, including two cambisols and two brunic arenosols. All sites contained naturally regenerating spruces 16–17 years of age.

The features of the forest stand and the biometric features of the saplings were determined for the selected stands on circular research plots. Altogether, the characteristicts of 400 saplings (100 in each region) were measured and analyzed using basic descriptive statistics. ANOVA with the Tukey’s multiple comparison test was performed to compare the features of forest stands and the natural regeneration of spruce in each region. The degree of interrelation between regeneration features was described by Pearson’s, ‘r’ factor or Spearman’s rank correlation coefficient. A discriminatory analysis was carried out to determine the set of regeneration features differentiating regions from each other.

The features of regeneration that differed between regions the most were: height of regeneration, basal diameter, mean height increment, and mean basal diameter increment of the saplings. The parameters for Warmia and the West-Pomerania Lake District were similar. The Augustów Forest showed the lowest values for the regeneration parameters, while the Kaszuby Lake District produced the highest values. The regeneration in the Kaszuby Lake District was markedly different from all other regions as indicated by more dynamic growth. Additionally, this population shows a great distinctness, indicating adaptation to local environmental conditions, which may be proof for the insular presence hypothesis of spruce in this region.

Due to their good quality, spontaneously developing natural regenerations in the Kaszuby Lake District should be supported by appropriate cutting and silvicultural measures.

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Combined presence of coagulation factor XIII V34L and plasminogen activator inhibitor 1 4G/5G gene polymorphisms significantly contribute to recurrent pregnancy loss in serbian population

Summary

Background

Recurrent pregnancy loss (RPL) is a heterogeneous condition affecting up to 5% of women of reproductive age. Inherited thrombophilia have been postulated as one of the causes of RPL. Here we examined the prevalence of nine thrombophilic gene polymorphisms among women with history of recurrent miscarriages and fertile controls.

Methods

The study included 70 women with history of at least three early pregnancy losses and 31 fertile controls with no miscarriages. We investigated mutations in genes responsible for clotting and fibrinolysis, including factor V (FV) Leiden, FV H1299R, factor II (FII) G20210A, methylene tetrahydrofolate reductase (MTHFR) C677T and A1298C, factor XIII (FXIII) V34L, plasminogen activator inhibitor-1 (PAI-1) 4G/5G and endothelial protein C receptor (EPCR) H1 and H3 haplotypes using reverse polymerase chain reaction ViennaLab cardiovascular disease StrippAssays.

Results

Our results showed no significant increase in prevalence of tested polymorphisms in women with RPL. However, relative risk for PRL among women heterozygous for FXIII V34L was 2.81 times increased (OR 2.81, 95% CI 1.15–6.87, P=0.023). Haplotype analysis showed that combined presence of high-risk genotypes for FXIII and PAI-1 significantly increases risk for RPL (OR 13.98, CI 95% 1.11–17.46, P=0.044).

Conclusions

This is the first study in Serbian population that investigated prevalence of FVR2, A1298C, FXIII V34L and EPCR gene variants. Compound heterozygosity for FXIII V34L and PAI-1 4G is significant risk factor for recurrent miscarriage. Our results should be viewed in context of small case-control study, so further large prospective studies are need for confirmation of our findings.

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Independence Number, Connectivity and All Fractional (a, b, k)-Critical Graphs

, Independence number, connectivity, and r-factors, J. Graph Theory 13 (1989) 63-69. doi: 10.1002/jgt.3190130109 [9] S. Zhou, Independence number, connectivity and (a, b, k)-critical graphs, Discrete Math. 309 (2009) 4144-4148. doi: 10.1016/j.disc.2008.12.013 [10] S. Zhou, Some results about component factors in graphs, RAIRO Oper. Res., ac- cepted. doi: 10.1051/ro/2017045 [11] S. Zhou, Q. Bian and Z. Sun, Binding numbers for all fractional (a, b, k)-critical graphs, Filomat 28 (2014) 709-713. doi: 10.2298/FIL1404709Z

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Forecasting Financial Performance for Quarries/ Předvídání Hospodářského Výsledku Lomů

References [1] DVOŘÁČEK, J., SOUSEDÍKOVÁ, R., BARTÁK, P., ŠTĚRBA, J. & ZAPLETALOVÁ, R. Factors controlling a quarry's profit. International Journal of Mining Reclamation and Environment. 2011, 25. Nr. 3, pp. 248-257. ISSN 1748-0930. [2] Profit influencing factors [online]. ExproSoft, ©2009, updated 05.12.2012 [cit. 2014-02-21]. Available from: http://www.exprobase.com/Default.aspx?Page=25 [3] CAAN, J. 3 Key Factors to Maximising Profit [online]. LinkedIn, ©2014. [cit. 2014-02-21]. Available from: http:// www

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Clinical presentation of extrahepatic portal vein obstruction: 10-year experience at a tertiary care hospital in Pakistan

SI, Poddar U, Yachha SK, Aggarwal R. Factor V Leiden and prothrombin gene G20210A mutations are uncommon in portal vein thrombosis in India. Indian J Gastroenterol 2006;25:236-9. 5. Dubuisson C, Boyer-Neumann C, Wolf M, Meyer D, Bernard O. Protein C, protein S and antithrombin III in children with portal vein obstruction. J Hepatol 1997;27:132-5. 6. Khanna R, Sarin SK. Non-cirrhotic portal hypertension — Diagnosis and management. J Hepatol 2014;60:421-41. 7. Kim SJ, Kim KM. Recent trends in the endoscopic management of variceal bleeding in children. Pediatr

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