Monitoring of Scour Around Bridge Piers and Abutments

AbstractScour of the riverbeds around bridge supports is the most frequent cause of their failures. Maintenance and repair costs of the bridges damaged by scour effects are significant, but it is estimated that the social costs are five times higher than the direct repair and replacement costs.The bridge supports are subjected to the scour effects due to the erosive action of the flowing water, involving soil loosening from the bottom and the banks of the watercourse. The condition for the proper monitoring of scour is to understand its nature. The knowledge of the phenomena occurring during the high water flow in the area of the bridge supports is crucial to properly assess the current condition and to develop proper maintenance actions.Scour may be the consequence of:•narrowing the watercourse – a natural or man-made, including construction of a bridge,•lateral movement or lowering of the stream bed,•hydraulic works shortening the length of the meandering section of the watercourse,•changes occurring in the catchment area of the watercourse,•other changes in watercourse hydrology.Construction of a bridge in the certain area disturbs natural stream flow conditions, especially the flood water and may change the terms of the normal water flow. The presence of a bridge causes the stream flow cross-section reduction, which increases the speed and intensity of erosion of the streambed. River tends to stabilize its bed in order to restore the natural flow section. Bridge supports also change the laminar water flow and turbulent flow.Scour present around a bridge supports can be monitored by the mobile and fixed devices.Portable scour monitoring devices are mainly: different types of probes such as: sticks, tape or rope with weights and bars used by divers and sonar acoustic measuring devices.Stationary equipment is used for continuous or regular scour monitoring of the bridge supports of the bridge, for example once a day, once a week. They are stationary devices including various types of robotic probes and stationary hydroacoustic measurement systems. Stationary device can be installed on a support or near the bridge, usually at the head of the pillar, or in the ground near the bottom of the watercourse. It should be installed near the site of the anticipated greatest scour. The device interacts with the data logger, which can be read on the site or transmitted to a remote control unit.The article presents the principles of scour monitoring near the bridge supports, developed during the project “Monitoring system for bridge supports and their surrounding areas” co-founded by the Polish National Centre for Research and Development under the program Innotech. During the project monitoring system for bridge supports was developed with specialized software for online data visualization. The article presents selected measurement results from the sonar measurements

The dual role of Escherichia coli in the course of ulcerative colitis

BACKGROUND: This study examines the dual role of Escherichia coli in the course of ulcerative colitis (UC). The intestinal microbiota is considered to play an important role in UC pathogenesis, but how E. coli contributes to inflammation in UC is still unknown. On the one hand, we demonstrated that there was a significant increase in the number of E. coli at the sites of inflammation in patients with UC, which can lead to immune system activation, whilst, on the other hand, E. coli may contribute to the resolution of inflammatory reactions since E. coli can inhibit hydroxyl radical formation by eliminating substrates of the Fenton reaction, by assimilating ferrous iron (Fe(2+)) and inducing the decomposition of hydrogen peroxide (H(2)O(2)). On this way, E. coli may affect the initiation and/or prolongation of remission stages of UC. METHODS: Ten E. coli strains were isolated from the colonic mucosa of patients in the acute phase of UC. Using PCR, we examined the presence of genes encoding catalases (katG and katE) and proteins participating in iron acquisition (feoB, fepA, fhuA, fecA, iroN, fyuA, and iutA) in these E. coli strains. To determine if iron ions influence the growth rate of E. coli and its ability to decompose H(2)O(2), we grew E. coli in defined culture media without iron (M9(-)) or with ferrous ions (M9(Fe(2+))). Expression levels of genes encoding catalases were examined by real-time PCR. RESULTS: All investigated E. coli strains had catalase genes (katG, katE), genes coding for receptors for Fe(2+) (feoB) and at least one of the genes responsible for iron acquisition related to siderophores (fepA, fhuA, fecA, iroN, fyuA, iutA). E. coli cultured in M9(Fe(2+)) grew faster than E. coli in M9(-). The presence of Fe(2+) in the media contributed to the increased rate of H(2)O(2) decomposition by E. coli and induced katG gene expression. CONCLUSIONS: E. coli eliminates substrates of the Fenton reaction by assimilating Fe(2+) and biosynthesizing enzymes that catalyze H(2)O(2) decomposition. Thus, E. coli can inhibit hydroxyl radical formation, and affects the initiation and/or prolongation of remission stages of UC

Wtórne przyczyny otyłości

Problem otyłości, którą określa się mianem epidemii XX i XXI wieku, dotyka stale rosnącej populacji, zwłaszcza w krajach rozwiniętych. Poza otyłością pierwotną, spowodowaną dodatnim bilansem energetycznym, wyróżnia się również otyłość wtórną. Otyłość wtórna najczęściej jest konsekwencją wielu chorób o podłożu hormonalnym i genetycznym. Jedną z przyczyn są zaburzenia w funkcji podwzgórza, między innymi guzy, urazy, a także wrodzone zespoły, takie jak zespół Pradera Williego oraz Bardeta-Biedla. Do innych przyczyn odpowiedzialnych za rozwój otyłości wtórnej zalicza się niewydolność przysadki, zespół Cushinga, niedoczynność tarczycy. Otyłość może być konsekwencją stosowania leków, między innymi glikokortykosteroidów oraz niektórych leków przeciwdepresyjnych. Ponadto w zespołach genetycznych, takich jak zespół Downa, Turnera i Klinefeltera, obserwuje się tendencję do tycia.The problem of obesity affects a growing number of people all over the world, especially in the developed countries. Aside from the primary obesity that is observed in most cases, caused by a positive energy balance, we can distinguish a secondary obesity. Secondary obesity may be caused by an impaired function of the hypothalamus, caused either by tumor, trauma or congenital, genetic syndromes like Prader Willi and Bardet-Biedl. Other causes include pituitary insufficiency due to tumor, trauma or congenital hypoplasia, as well as Cushing’s syndrome, hypothyroidism, and certain medications — corticosteroids and antidepressants. Moreover, genetic syndromes such as the Down, Turner and Klinefelter syndromes also have a tendency to cause weight gain

Granice ingerencji turystyki surwiwalowej w tereny przyrodnicze o różnym reżimie ochronnym

Surwiwal jako forma turystyki i rekreacji wymaga dostępu do zasobów przyrodniczych, w tym tych o wysokim stopniu naturalności. Obszary te ze względu na walory przyrodnicze i funkcje środowiskowe podlegają różnym reżimom ochronny. W artykule dokonano analizy obowiązujących regulacji prawnych oraz oceniono wpływ poszczególnych rodzajów zajęć z surwiwalu na obszary przyrodnicze. W konkluzji stwierdza się, że regulacje prawne stanowią istotny czynnik warunkujący możliwość uprawiania surwiwalu na terenie Polski, podejmowanie tej formy aktywności musi odbywać się przy ścisłej współpracy z właścicielami oraz zarządzającymi terenów, zaś stopień ingerencji w środowisko naturalne jest uzależniony od tematyki zajęć oraz czasu ich trwania

Bacterial infections of the lower genital tract in fertile and infertile women from the southeastern Poland

Objectives: The objective of the study was to investigate the detection rates of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, Gardnerella vaginalis, Escherichia coli, Streptococcus agalactiae and Enterococcus faecalis, showing no clinical signs of an ongoing, acute inflammatory state of the vagina and/or the cervix, in fertile and infertile women. Material and methods: The study encompassed 161 women, including 101 women treated for infertility and 60 fertile women who had already given birth to healthy children. The material for the presence of C. trachomatis, N. gonorrhoeae, M. genitalium, M. hominis and U. urealyticum was collected from the cervical canal and analyzed by PCR. Furthermore, BD ProbeTec ET system was used to detect C. trachomatis infection. Vaginal swabs were collected for classification of bacterial vaginosis and aerobic vaginitis and assessed according to the Nugent score, as well as by traditional culture methods. Results: U. urealyticum was identified in 9% of the infertile women and in 8% of controls. Presence of M. hominis was demonstrated only in the former (4%) and C. trachomatis only in latter (3%). N. gonorrhoeae and M. genitalium were not found in any of the examined women. The frequency of aerobic vaginitis in both groups was estimated at 12%. There were 7% bacterial vaginosis cases in the study group, and none in the control group (p=0.0096). Conclusions: Despite having no symptoms of an ongoing acute inflammation of the reproductive tract, many women may experience permanent or periodic shifts of equilibrium of the vaginal and/or cervical microflora. BV develops more frequently in infertile patients when compared to the fertile women

Persistent cyanobacteria blooms in artificial water bodies : an effect of environmental conditions or the result of anthropogenic change

Algal blooms are an emerging problem. The massive development of phytoplankton is driven partly by the anthropogenic eutrophication of aquatic ecosystems and the expansion of toxic cyanobacteria in planktonic communities in temperate climate zones by the continual increase in global temperature. Cyanobacterial harmful algal blooms (CyanoHABs) not only disturb the ecological balance of the ecosystem, but they also prevent the use of waterbodies by humans. This study examines the cause of an unusual, persistent bloom in a recreational, flow-through reservoir; the findings emphasize the role played by the river supplying the reservoir in the formation of its massive cyanobacterial bloom. Comprehensive ecosystem-based environmental studies were performed, including climate change investigation, hydrochemical analysis, and bio-assessment of the ecological state of the river/reservoir, together with monitoring the cyanobacteria content of phytoplankton. Our findings show that the persistent and dominant biomass of Microcystis was related to the N/P ratio, while the presence of Aphanizomenon and Dolichospermum was associated with the high-temperature end electric conductivity of water. Together with the increase in global temperature, the massive and persistent cyanobacterial bloom appears to be maintained by the inflow of biogenic compounds carried by the river and the high electric conductivity of water. Even at the beginning of the phenomenon, the reservoir water already contained cyanobacterial toxins, which excluded its recreational use for about half the year

Efficacy and safety of a vaginal medicinal product containing three strains of probiotic bacteria : a multicenter, randomized, double-blind, and placebo-controlled trial

Objective: The main objective of this study was to evaluate whether vaginal administration of probiotic Lactobacillus results in their colonization and persistence in the vagina and whether Lactobacillus colonization promotes normalization and maintenance of pH and Nugent score. Patients and methods: The study was a multicenter, randomized, double-blind, and placebocontrolled trial. Altogether, 376 women were assessed for eligibility, and signed informed consent. One hundred and sixty eligible women with abnormal, also called intermediate, vaginal microflora, as indicated by a Nugent score of 4-6 and pH >4.5 and zero or low Lactobacillus count, were randomized. Each participant was examined four times during the study. Women were randomly allocated to receive either the probiotic preparation inVag®, or a placebo (one capsule for seven consecutive days vaginally). The product inVag includes the probiotic strains Lactobacillus fermentum 57A, Lactobacillus plantarum 57B, and Lactobacillus gasseri 57C. We took vaginal swabs during visits I, III, and IV to determine the presence and abundance of bacteria from the Lactobacillus genus, measure the pH, and estimate the Nugent score. Drug safety evaluation was based on analysis of the types and occurrence of adverse events. Results: Administration of inVag contributed to a significant decrease (between visits) in both vaginal pH (P<0.05) and Nugent score (P<0.05), and a significant increase in the abundance of Lactobacillus between visit I and visits III and IV (P<0.05). Molecular typing revealed the presence of Lactobacillus strains originating from inVag in 82% of women taking the drug at visit III, and 47.5% at visit IV. There was no serious adverse event related to inVag administration during the study. Conclusion: The probiotic inVag is safe for administration to sustainably restore the healthy vaginal microbiota, as demonstrated by predominance of the Lactobacillus bacteria in vaginal microbiota