Chromosome identification and gene mapping in potato by pachytene, trisomic and half-tetrad analysis = [Chromosoomidentificatie en gen-kartering bij de aardappel door middel van pachyteen- trimosomen- en halftetraden-analyse]

The research described in this thesis deals with chromosome identification and gene mapping. In contrast to results from literature, in this study only three chromosomes (1, 2 and 12) could unambiguously be identified in mitotic cells using conventional staining, and four (1, 2, 3 and 4) in case of Giemsa C-banding. With both methods the chromosomes 1 and 2 could unambiguously be identified and are homologous to the chromosomes 1 and 2 as identified by pachytene analysis. Reliable chromosome identification in potato can be achieved by pachytene analysis.It was found in this study by using non-radioactive in situ hybridization that one basic chromosome of the potato contains rRNA genes. In contrast to a report in the literature about detection of one chromosome with gene(s) for patatin using a cDNA clone, hybridization with a genomic DNA clone used in this study detected more than one basic chromosome carrying genes related to patatin.The bivalents in S. phureja Juz. et Buk. were morphologically very similar to those of S. tuberosum L. ssp. tuberosum Hawkes cv. Gineke as identified by pachytene analysis. An interchange in S. phureja is described and the involvement of the chromosomes 3 and 12 in this interchange could clearly be demonstrated by pachytene analysis and the meiotic behaviour in F 1 hybrids. Trisomic descendants selected in the first selfed generation of the interchange heterozygote were primary trisomic being homozygous for the interchange or tertiary trisomic.Meiotic behaviour in 11 primary trisomics was investigated and female transmission of the extra chromosome determined. Triple synapsis of pachytene chromosomes was often found in the euchromatic parts of the chromosomes. In this study a significant correlation between the relative chromosome or euchromatin length and the coefficient of realization of a trivalent at metaphase 1 was found in the primary trisomics of the potato. In spite of this result no relationship could be established between female transmission and the length of the extra chromosome.By means of half-tetrad analysis the map distance relative to the centromere could be estimated of each of three dominant genes involved in resistance to potato viruses X and Y and to pathotype Ro1 from Globodera rostochiensis , and of the recessive gene for yellow leaf- margin. The gene for yellow margin was localized on chromosome 12 and that for topiary on chromosome 3 by means of trisomic analysis

Exact and heuristic approaches for the ship-to-shore problem

After a natural disaster such as a hurricane or flooding, the navy can help by bringing supplies, clearing roads, and evacuating victims. If destinations cannot be reached over land, resources can be transported using smaller ships and helicopters, called connectors. To start aid on land as soon as possible this must be done efficiently. In the ship-to-shore problem, trips with their accompanying resources are determined while minimising the makespan. Limited (un)loading capacities, heterogeneous connector characteristics and constraints posed by priority of the resources and grouping of the resources (resource sets) all require that the connector trips are carefully coordinated. Despite the criticality of this coordination, existing literature does not consider resource sets and has only developed heuristics. We provide a formulation that incorporates resource sets and develop (i) an exact branch-and-price algorithm and (ii) a tailored greedy heuristic that can provide upper bounds. We find that 84% of our 98 practical instances terminate within an hour in on average 80 s. Our greedy heuristic can find optimal solutions in two-thirds of these instances, mostly for instances that are very constrained in terms of the delivery order of resources. When improvements are found by the branch-and-price algorithm, the average gap with the makespan of the greedy solution is 40% and, in most cases, these improvements are obtained within three minutes. For the 20 artificial instances, the greedy heuristic has consistent performance on the different types of instances. For these artificial instances improvements of on average 35% are found in reasonable time.</p

The financing of Italian firms and the credit crunch: findings and exit strategies

The aim of the paper is to analyse how credit crunch has modified the traditional bank-firm relationship with a particular attention to the Italian situation. Our analysis reinforces the finding that in Italy, the credit available to the real economy is insufficient in terms not only of quantity but also of quality. The subsequent step is to identify and discuss possible exit strategies for eliminating the credit crunch and to overcome serious intrinsic shortcomings in terms of alternative instruments, markets and intermediaries. In fact, if on the one hand the crisis has revealed the underdevelopment of the Italian financial market, the insufficient role of institutional investors, the embryonic state of the corporate bond markets and the virtual non-existence of commercial paper markets; on the other hand, it could finally provide the opportunity for the development of these channels. The changing role of banks in the new scenario is also analysed as well as the characteristics firms will require to benefit from it

Development and Validation of an On-Line Water Toxicity Sensor with Immobilized Luminescent Bacteria for On-Line Surface Water Monitoring.

Surface water used for drinking water production is frequently monitored in The Netherlands using whole organism biomonitors, with for exampleDaphnia magnaorDreissenamussels, which respond to changes in the water quality. However, not all human-relevant toxic compounds can be detected by these biomonitors. Therefore, a new on-line biosensor has been developed, containing immobilized genetically modified bacteria, which respond to genotoxicity in the water by emitting luminescence. The performance of this sensor was tested under laboratory conditions, as well as under field conditions at a monitoring station along the river Meuse in The Netherlands. The sensor was robust and easy to clean, with inert materials, temperature control and nutrient feed for the reporter organisms. The bacteria were immobilized in sol-gel on either an optical fiber or a glass slide and then continuously exposed to water. Since the glass slide was more sensitive and robust, only this setup was used in the field. The sensor responded to spikes of genotoxic compounds in the water with a minimal detectable concentration of 0.01 mg/L mitomycin C in the laboratory and 0.1 mg/L mitomycin C in the field. With further optimization, which should include a reduction in daily maintenance, the sensor has the potential to become a useful addition to the currently available biomonitors

Язык современных СМИ как механизм интерпретации в контексте национальной культуры

Автор, опираясь на различные труды по лингвокультурологии, риторике, социальной информациологии и информационной политике, рассматривает язык современных средств массовой информации России как механизм интерпретации национальной культуры. В работе раскрыты понятия интертекстуальности и интерпретации в языке СМИ, обозначена специфика речевого поведения современных журналистов, показаны особенности языковых моделей массовой и качественной прессы.Автор, звертаясь до різноманітних трудів по лінгвокультурології ріторіки, соціальної інформаціології та інформаційної політики, розглядає мову сучасних засобів масової інформації Росії як механізм інтерпретації національної культури. В роботі відкрити поняття інтертекстуальністі в мові ЗМІ, визначена специфіка речової поведінки сучасних журналістів, відображені особистості мовних моделей масової та якісної преси.Drawing on various works on linguistic culturology, rhetorics, social informatiology and information policy, the author examines the language of modern mass media on Russia as a mechanism for interpreting national culture. The paper dwells on the concepts of intertextuality and interpretation in the language of mass media, peculiarities of modern journalists' speech behaviour and characteristic features of language models of mass and specialized media

Risk Allocation in Toll Highway Concessions in Spain: Lessons from Economic Recession

Spain has a long tradition of encouraging toll highways by granting concessions to private companies. Concessions in Spain have been characterized by a willingness to transfer considerable risk to the private sector. Traffic demand, acquisition of the right-of-way, and financial risk have often been allocated to the private sector. From 1996 to 2011, 16 toll highway concessions, covering a total distance of 835 km, were awarded by the central government of Spain with this approach. Some of those highways started their operations just before the economic recession began. The recession had negative consequences for Spain's economy. The gross domestic product per capita plummeted, and the unemployment rate increased from 9% to 20% of the working population in just 2 years. The recession also had severe consequences for the economic performance of toll highway concessions. Traffic levels declined at a much greater rate than did the gross domestic product. In addition, the conditions imposed by the financial markets on borrowers became much stricter because of the liquidity crisis. This study analyzes the impact that the economic recession ultimately had on the performance of toll highway concessions in Spain and the actions that the government adopted to avoid the bankruptcy of the concessionaires. It was found that the economic recession helped identify some deficiencies in how risk had been allocated in Spain. The measures that both Spain and the European Union are adopting so as to improve risk allocation are discussed

Physiologic and molecular consequences of endothelial Bmpr2 mutation

<p>Abstract</p> <p>Background</p> <p>Pulmonary arterial hypertension (PAH) is thought to be driven by dysfunction of pulmonary vascular microendothelial cells (PMVEC). Most hereditary PAH is associated with BMPR2 mutations. However, the physiologic and molecular consequences of expression of BMPR2 mutations in PMVEC are unknown.</p> <p>Methods</p> <p>In vivo experiments were performed on adult mice with conditional endothelial-specific expression of the truncation mutation Bmpr2^delx4+, with age-matched transactivator-only mice as controls. Phenotype was assessed by RVSP, counts of muscularized vessels and proliferating cells, and staining for thromboses, inflammatory cells, and apoptotic cells. The effects of BMPR2 knockdown in PMVEC by siRNA on rates of apoptosis were assessed. Affymetrix expression arrays were performed on PMVEC isolated and cultured from triple transgenic mice carrying the immortomouse gene, a transactivator, and either control, Bmpr2^delx4+or Bmpr2^R899Xmutation.</p> <p>Results</p> <p>Transgenic mice showed increased RVSP and corresponding muscularization of small vessels, with histologic alterations including thrombosis, increased inflammatory cells, increased proliferating cells, and a moderate increase in apoptotic cells. Expression arrays showed alterations in specific pathways consistent with the histologic changes. Bmpr2^delx4+and Bmpr2^R899Xmutations resulted in very similar alterations in proliferation, apoptosis, metabolism, and adhesion; Bmpr2^delx4+cells showed upregulation of platelet adhesion genes and cytokines not seen in Bmpr2^R899XPMVEC. Bmpr2 mutation in PMVEC does not cause a loss of differentiation markers as was seen with Bmpr2 mutation in smooth muscle cells.</p> <p>Conclusions</p> <p>Bmpr2 mutation in PMVEC <it>in vivo </it>may drive PAH through multiple, potentially independent, downstream mechanisms, including proliferation, apoptosis, inflammation, and thrombosis.</p

How does healthcare worker hand hygiene behaviour impact upon the transmission of MRSA between patients?: an analysis using a Monte Carlo model

BACKGROUND: Good hand hygiene has for many years been considered to be the most important measure that can be applied to prevent the spread of healthcare-associated infection (HAI). Continuous emphasis on this intervention has lead to the widespread opinion that HAI rates can be greatly reduced by increased hand hygiene compliance alone. However, this assumes that the effectiveness of hand hygiene is not constrained by other factors and that improved compliance in excess of a given level, in itself, will result in a commensurate reduction in the incidence of HAI. However, there is evidence that the law of diminishing returns applies to hand hygiene, with the greatest benefits occurring in the first 20% or so of compliance. While this raises intriguing questions about the extent to which increasing compliance alone can further reduce rates of HAI, analysis of this subject has been hampered by a lack of quantifiable data relating to the risk of transmission between patients on wards. METHODS: In order to gain a greater understanding of the transmission of infection between patients via the hands of healthcare workers (HCWs), we constructed a stochastic Monte Carlo model to simulate the spread of methicillin-resistant Staphylococcus aureus (MRSA) between patients. We used the model to calculate the risk of transmission occurring, firstly between two patients in adjacent beds, and then between patients in a four-bedded bay. The aim of the study was to quantify the probability of transmission under a variety of conditions and thus to gain an understanding of the contribution made by the various factors which influence transmission. RESULTS: The study revealed that on a four-bedded bay, the average probability of transmitting an infection by the handborne route is generally low (i.e. in the region 0.002 - 0.013 depending on the hand hygiene behaviour of HCWs and other factors). However, because transmission is strongly influenced by stochastic events, it is the frequency with which 'high-risk events' occur, rather than average probability, that governs whether or not transmission will take place. The study revealed that increased hand hygiene compliance has a dramatic impact on the frequency with which 'high-risk events' occur. As compliance increases, so the rate at which 'high-risk events' occur, rapidly decreases, until a point is reached, beyond which, further hand hygiene is unlikely to yield any greater benefit. CONCLUSION: The findings of the study confirm those of other researchers and suggest that the greatest benefits derived from hand hygiene occur as a result of the first tranche of compliance, with higher levels (>50%) of hand hygiene events yielding only marginal benefits. This suggests that in most situations relatively little benefit is accrued from seeking to achieve very high levels of hand hygiene compliance