Influence of track arrangement on expanding rail corridor capacity and operations

The North American freight railroad network is projected to experience rising freight transportation demand in the coming decades, coupled with continued interest in expanding passenger services. Congestion resulting from these demands strains the capacity of rail lines and jeopardizes the operational fluidity of the rail network, particularly along shared rail corridors. While track construction is just one of many alternatives a railroad may employ in expanding practical capacity (and thereby boosting throughput), this practice represents substantial capital investment. With the purpose of helping rail practitioners better utilize their resources, this thesis aims to investigate track expansion alternatives in detail, ultimately providing an improved understanding of the link between track arrangement, train delay, and line capacity. The majority of mainline rail corridors in North America consist predominantly of single track with passing sidings or short sections of double track. These track arrangements lack the flexibility to reliably handle high traffic volumes composed of multiple types of trains. Increasing frequency of long freight-train operations also magnifies capacity constraints posed by inadequate, short sidings. This work explores the capacity benefits of siding expansion to meet these developing operational needs, leading to a discussion of the incremental capacity in transitioning from single to double and triple track, both from a quantitative and qualitative perspective. Experiment designs are carried out in Rail Traffic Controller simulation software to reveal fundamental relationships between track arrangement and other capacity factors via statistical analysis of the results. While railroads must consider many factors in selecting capital expansion projects, the trends identified through this research can help streamline the planning process by helping industry practitioners quickly identify track expansion project alternatives with the greatest potential capacity benefit for more detailed engineering evaluation

Archaeal and bacterial diversity in two hot springs from geothermal regions in Bulgaria as demostrated by 16S rRNA and GH-57 genes

Archaeal and bacterial diversity in two Bulgarian hot springs, geographically separated with different tectonic origin and different temperature of water was investigated exploring two genes, 16S rRNA and GH-57. Archaeal diversity was significantly higher in the hotter spring Levunovo (LV) (82°C); on the contrary, bacterial diversity was higher in the spring Vetren Dol (VD) (68°C). The analyzed clones from LV library were referred to twenty eight different sequence types belonging to five archaeal groups from Crenarchaeota and Euryarchaeota. A domination of two groups was observed, Candidate Thaumarchaeota and Methanosarcinales. The majority of the clones from VD were referred to HWCG (Hot Water Crenarchaeotic Group). The formation of a group of thermophiles in the order Methanosarcinales was suggested. Phylogenetic analysis revealed high numbers of novel sequences, more than one third of archaeal and half of the bacterial phylotypes displayed similarity lower than 97% with known ones. The retrieved GH-57 gene sequences showed a complex phylogenic distribution. The main part of the retrieved homologous GH-57 sequences affiliated with bacterial phyla Bacteroidetes, Deltaproteobacteria, Candidate Saccharibacteria and affiliation of almost half of the analyzed sequences is not fully resolved. GH-57 gene analysis allows an increased resolution of the biodiversity assessment and in depth analysis of specific taxonomic groups. [Int Microbiol 18(4):217-223 (2015)]Keywords: Archaea · hot spring · phylogenetic analysis · 16S rRNA gene · GH-57 gen

Genetic control of flower petal number in Rosa x Damascena Mill f. trigintipetala

We studied the petal number trait in a population obtained after self-pollination of R. x damascena f. trigintipetala following analysis of molecular markers which have previously been mapped near the major dominant locus Blfo/d6 determining this trait in other rose species including R. multiflora and R. hybrida. The results showed that the same genetic mechanism, which determines the petal number trait in R. multiflora and R. hybrida also controls the trait in R. x damascena f. trigintipetala and is related to the dominant effect of a single copy allele in the tetraploid genome of this species. We also analyzed the expression of several flower homeotic genes including R. x damascena APETALA1/FUL-like (paleo AP1 type), R. x damascena euAPETALA 3 (euAP3 line) and R. x damascena AGAMOUS in early stage flower buds corresponding to plants with double and simple flowers. The obtained results showed that only R. x damascena AGAMOUS was differentially expressed between the samples of double and simple flowers, its relative expression being upregulated 3.5-fold in simple flowers. We further cloned and sequenced the four genomic clones of R. x damascena AGAMOUS and studied the potential additive effect of this gene by analysing the segregation of its four alleles in the population of self-pollinated R. x damascena. Analysis of variance of the data for petal number and allele segregation did not show a statistically significant effect of any allele configuration of the AGAMOUS gene on the petal number trait in R. x damascena f. trigintipetala

Influence of Malolactic Fermentation on the Quality of Riesling Wine

Biotic and abiotic stress has a negative effect on both the quality and quantity of grape production. Like many woody crops, grape has been relatively recalcitrant to in vitro manipulations. The crucial point in the process of genetic transformation is to have cells that are able to both regenerate and be transformed. A regeneration system seems to be a major problem in the transformation process. Somatic embryogenesis is the favoured regenerative protocol in genetic transformations of grapes. Comparison of an embryogenic and organogenic system in grape demonstrated that organogenesis frequently leads to chemical transformation of tissues. In this respect we started to develop and apply procedures suitable for the genetic transformation of grapevine. Two sources of explants were used for embryo induction. In the first case, immature zygotic ovules of Vitis vinifera seedless genotypes were used. In the second case in vivo leaf tissues from rootstocks Vitis rupestris cv. Rupestris du Lot and 110 Richter (Vitis berlandieri x Vitis rupestris). Continual transfer to fresh medium maintained embryogenic cultures. Agrobacterium tumefaciens mediated transformation of enbryogenic cultures of seedless grapes (Vitis vinifera L.) with constructs containing the gene encoding the coat protein of Grape Fanleaf Virus (GFLV) and with four constructs containing genes encoding for an antifreeze protein. An embryogenic culture of rootstock Vitis rupestris cv. Rupestris du Lot was transformed with a construct carrying the bete-glucoronidase (GUS) gene. The first transformed plantlets have been regenerated from somatic embryos and the presence of the NPTII gene was verified by PCR and Southern blot analyses

S-Acylation of the cellulose synthase complex is essential for its plasma membrane localization.

Plant cellulose microfibrils are synthesized by a process that propels the cellulose synthase complex (CSC) through the plane of the plasma membrane. How interactions between membranes and the CSC are regulated is currently unknown. Here, we demonstrate that all catalytic subunits of the CSC, known as cellulose synthase A (CESA) proteins, are S-acylated. Analysis of Arabidopsis CESA7 reveals four cysteines in variable region 2 (VR2) and two cysteines at the carboxy terminus (CT) as S-acylation sites. Mutating both the VR2 and CT cysteines permits CSC assembly and trafficking to the Golgi but prevents localization to the plasma membrane. Estimates suggest that a single CSC contains more than 100 S-acyl groups, which greatly increase the hydrophobic nature of the CSC and likely influence its immediate membrane environment.Biotechnology and Biological Sciences Research Council (Grant IDs: BB/H012923/1, BB/M004031/1, BB/M024911/1); Gatsby Charitable FoundationThis is the author accepted manuscript. The final version is available from the American Association for the Advancement of Science via http://dx.doi.org/10.1126/science.aaf400

Assessment of the botanical origin of Bulgarian honey samples using melissopalynological, DNA barcoding and NMR analyses

Polyfloral honey samples from Bulgaria were subject to parallel analyses of their botanical origin and composition using traditional melissopalynology, DNAbarcoding based on the plastid rbcL gene and NMR analysis. The obtained datasets were compared with each other to evaluate the information capacity of the applied experimental methods. The results from the melissopalynological and DNA-barcoding studies demonstrated a significantly higher resolution of the latter, revealing the presence of pollen from a total of 17 plant families, 21 plant genera and 5 plant species in comparison to pollen from only 7 plant families, 3 plant genera and 4 plant species identified by melissopalynology. The higher resolution of DNA barcoding allows a more detailed characterisation of the diet and foraging preferences of honey bees, including foraging on plant species growing in lower abundance in the area. The comparison of the quantitative data on floral honey composition for several plant genera and species reveals significant differences between the relative abundance of the pollen grains estimated by melissopalynological analysis and the relative abundance of rbcL clones in rbcL libraries determined after DNA barcoding. All three applied methods confirm the polyfloral botanical origin of the analysed samples and support routine NMR use for the assessment of the floral origin of honey

A new weighted Monte Carlo algorithm for elastic electron backscattering from surfaces

info:eu-repo/semantics/nonPublishe

Functional analysis of cellulose synthase (CESA) protein class-specificity

The cellulose synthase complex (CSC) exhibits a 6-fold symmetry and is known as a “rosette.” Each CSC is believed to contain between 18 and 24 CESA proteins that each synthesize an individual glucan chain. These chains form the microfibrils that confer the remarkable structural properties of cellulose. At least three different classes of CESA proteins are essential to form the CSC. However, while organization of the CSC determines microfibril structure, how individual CESA proteins are organized within the CSC remains unclear. Parts of the plant CESA proteins map sufficiently well onto the bacterial CESA (BcsA) structure, indicating that they are likely to share a common catalytic mechanism. However, plant CESA proteins are much larger than the bacterial BcsA protein, prompting the suggestion that these plant-specific regions are important for interactions between CESA proteins and for conferring CESA class specificity. In this study, we have undertaken a comprehensive analysis of well-defined regions of secondary cell wall CESA proteins, with the aim of defining what distinguishes different CESA proteins and hence what determines the specificity of each CESA class. Our results demonstrate that CESA class specificity extends throughout the protein and not just in the highly variable regions. Furthermore, we find that different CESA isoforms vary greatly in their levels of site specificity and this is likely to be determined by the constraints imposed by their position within the CSC rather than their primary structure

Exact Error Estimates and Optimal Randomized Algorithms for Integration ⋆

Abstract. Exact error estimates for evaluating multi-dimensional integrals are considered. An estimate is called exact if the rates of convergence for the low- and upper-bound estimate coincide. The algorithm with such an exact rate is called optimal. Such an algorithm has an unimprovable rate of convergence. The problem of existing exact estimates and optimal algorithms is discussed for some functional spaces that define the regularity of the integrand. Important for practical computations data classes are considered: classes of functions with bounded derivatives and Hölder type conditions. The aim of the paper is to analyze the performance of two optimal classes of algorithms: deterministic and randomized for computing multidimensional integrals. It is also shown how the smoothness of the integrand can be exploited to construct better randomized algorithms.

A simple, flexible and efficient PCR-fusion/Gateway cloning procedure for gene fusion, site-directed mutagenesis, short sequence insertion and domain deletions and swaps

BACKGROUND: The progress and completion of various plant genome sequencing projects has paved the way for diverse functional genomic studies that involve cloning, modification and subsequent expression of target genes. This requires flexible and efficient procedures for generating binary vectors containing: gene fusions, variants from site-directed mutagenesis, addition of protein tags together with domain swaps and deletions. Furthermore, efficient cloning procedures, ideally high throughput, are essential for pyramiding of multiple gene constructs. RESULTS: Here, we present a simple, flexible and efficient PCR-fusion/Gateway cloning procedure for construction of binary vectors for a range of gene fusions or variants with single or multiple nucleotide substitutions, short sequence insertions, domain deletions and swaps. Results from selected applications of the procedure which include ORF fusion, introduction of Cys>Ser mutations, insertion of StrepII tag sequence and domain swaps for Arabidopsis secondary cell wall AtCesA genes are demonstrated. CONCLUSION: The PCR-fusion/Gateway cloning procedure described provides an elegant, simple and efficient solution for a wide range of diverse and complicated cloning tasks. Through streamlined cloning of sets of gene fusions and modification variants into binary vectors for systematic functional studies of gene families, our method allows for efficient utilization of the growing sequence and expression data