Prevalence and abundance of Cryptosporidium parvum and Giardia spp. in wild rural rodents from the Mazury Lake District region of Poland

Prevalence and abundance of Cryptosporodium parvum and Giardia spp. were studied in 3 species of rodents from forests and abandoned agricultural fields in N.E. Poland (Clethrionomys glareolus n=459; Microtus arvalis n=274; Apodemus flavicollis n=209). Overall prevalence was consistently higher in the voles compared with A. flavicollis (70±6, 73±0 and 27±8% respectively for C. parvum and 93±9, 96±3 and 48±3% respectively for Giardia spp.). Prevalence and abundance of infection also varied markedly across 3 years with 1998 being a year of higher prevalence and abundance with both species. Fewer older animals (especially C. glareolus and M. arvalis) carried infection with C. parvum and infections in these animals were relatively milder. Although seasonal differences were significant, no consistent pattern of changes was apparent. Host sex did not influence prevalence or abundance of infection with C. parvum, but made a small contribution to a 4-way interaction (in 5-way ANOVA) with other factors in the case of Giardia spp. The 2 species co-occurred significantly and in animals carrying both parasites there was a highly signficant positive correlation between abundance of infection with each, even with between-year, seasonal, host age, sex and species differences taken into account. Quantitative associations were confined to the 2 vole species in the study. These results are discussed in relation to the importance of wild rodents as reservoir hosts and sources of infection for local human communities

Active sound radiation control with secondary sources at the edge of the opening

© 2016 Elsevier Ltd Planar virtual sound barriers with secondary sources over the entire opening have been demonstrated an effective way to achieve global control of sound transmission through the opening, but loudspeakers in the middle of the opening affect ventilation, lighting and normal access through it. To avoid the problem, this technical note proposes to implement secondary sources at the edge of a cavity opening and investigates the active sound reduction performance of the system numerically and experimentally. Unlike secondary sources over the entire opening which can achieve sound reduction at any frequency as long as there are sufficient of them, there exists an upper bound of effective frequency for global control when secondary sources are at the edge of the opening; however, local control is always achievable. Preliminary experiments were conducted on an open wooden box and a semi-closed meeting room to support the conclusions

Występowanie zakażeń Chlamydia trachomatis u kobiet z niepłodnością w Polsce

Introduction: Chlamydia trachomatis represents a causal factor of sexually transmitted infections (STI), the course of which is frequently asymptomatic. Chronic and relapsing infections with Chlamydia trachomatis may result in a disturbed function of oviducts, resulting in infertility. Objectives: The aim of the study was to evaluate the relationship between manifestations of asymptomatic infections with Chlamydia trachomatis and infertility among Polish women. Material and Methods: The study was conducted between 2010-2013 on 543 women in two groups. Group 1 included 190 patients (aged 23-39 years), in whom control tests were performed before planned pregnancy. Group 2 included 353 patients (aged 23-39 years), suffering from infertility (no pregnancy after 12 months of regular sexual intercourse). The study included all women presenting with infertility. A smear was taken from the cervical canal and DNA of C. trachomatis was isolated and identified using nested-PCR. In the statistical analysis the Fisher’s exact test was applied. Results: Infection with C. trachomatis was detected in 18 (9.47%) controls (group 1) but as many as 81 (22.95%) patients with infertility (group 2). The obtained results were significantly different (pWstęp: Chlamydia trachomatis jest czynnikiem przyczynowym zakażeń przenoszonych drogą płciową (STD), których przebieg kliniczny jest często bezobjawowy. Rezultatem przewlekłych i nawracających zakażeń Chlamydia trachomatis mogą być zaburzenia funkcji jajowodów prowadzące do niepłodności. Cel: Celem badań było dokonanie oceny współzależności pomiędzy występowaniem bezobjawowych zakażeń Chlamydia trachomatis i niepłodnością u kobiet w Polsce. Materiał i Metody: Badania przeprowadzono w latach 2010-2013 u 543 kobiet w 2 grupach. Grupa 1 obejmowała 190 pacjentek, w wieku 23-39 lat, u których przeprowadzono badania kontrolne przed planowaną ciążą. Grupa 2 obejmowała 353 pacjentki, w wieku 23-39 lat, z niepłodnością (brak ciąży po 12 miesiącach regularnego współżycia). Badanie obejmowało wszystkie zgłaszające się chore z niepłodnością. Z materiału pobranego z ujścia kanału szyjki macicy izolowano DNA C. trachomatis i identyfikowano przy użyciu metody nested-PCR. W analizie statystycznej zastosowano dokładny test Fishera. Wyniki: Zakażenie C. trachomatis stwierdzono u 18 (9,47%) pacjentek z kontrolnej grupy 1. Z kolei, w grupie 2 zakażenie C. trachomatis stwierdzono u 81 (22,95%) pacjentek z niepłodnością co stanowi różnicę istotną statystycznie (

Medium-term temporal stability of the helminth component community structure in bank voles (Clethrionomys glareolus) from the Mazury Lake District region of Poland

The structure of helminth communities in wild rodents is subject to seasonal variation, and is dependent on host age within years. Although between-year variation has been monitored, seldom has it been assessed rigorously by appropriate multifactorial analysis with potentially confounding factors taken into account. In this study we tested the null hypothesis that despite seasonal, host age and sex effects, helminth communities should show relative stability between years. Over a period of 3 years (1998–2000) we sampled bank vole (Clethrionomys glareolus) populations (total n=250) at 2 points in the year: in spring, at the start of the breeding season, and in autumn, after the cessation of breeding. In spite of seasonal differences and strong age effects, the between-year effects were surprisingly small. Measures of component community structure (Berger- Parker dominance index, the dominant species, S. petrusewiczi) did not vary, or varied only slightly from year to year. The majority of measures of infracommunity structure [Brillouin’s index of diversity, prevalence of all helminths combined, prevalence and abundance of H. mixtum (the most prevalent helminth), mean species richness] did not differ significantly between years when other factors such as age, sex and seasonal variation had been taken into account. Some between-year variations were found (at the component community level, Simpson’s index of diversity ; at the infracommunity level, prevalence and abundance of S. petrusewiczi and abundance of all helminths combined), but even these were modest in comparison to seasonal and age differences, and were primarily attributable to S. petrusewiczi. We conclude that despite dynamic within-year fluctuations, helminth communities in bank voles in this region of Poland show relative stability across years. The sporadic occurrence of individual platyhelminths at low prevalence, makes little difference to the overall structure, which is largely maintained by the key roles played by the dominant intestinal nematodes of bank voles and the rarer species collectively

Matrix dynamics of fuzzy spheres

We study the dynamics of fuzzy two-spheres in a matrix model which represents string theory in the presence of RR flux. We analyze the stability of known static solutions of such a theory which contain commuting matrices and SU(2) representations. We find that irreducible as well as reducible representations are stable. Since the latter are of higher energy, this stability poses a puzzle. We resolve this puzzle by noting that reducible representations have marginal directions corresponding to non-spherical deformations. We obtain new static solutions by turning on these marginal deformations. These solutions now have instability or tachyonic directions. We discuss condensation of these tachyons which correspond to classical trajectories interpolating from multiple, small fuzzy spheres to a single, large sphere. We briefly discuss spatially independent configurations of a D3/D5 system described by the same matrix model which now possesses a supergravity dual.Comment: 26 pages, 3 figures, uses JHEP.cls; (v2) references adde

Deforming baryons into confining strings

We find explicit probe D3-brane solutions in the infrared of the Maldacena-Nunez background. The solutions describe deformed baryon vertices: q external quarks are separated in spacetime from the remaining N-q. As the separation is taken to infinity we recover known solutions describing infinite confining strings in ${\mathcal{N}}=1$ gauge theory. We present results for the mass of finite confining strings as a function of length. We also find probe D2-brane solutions in a confining type IIA geometry, the reduction of a G_2 holonomy M theory background. The relation between these deformed baryons and confining strings is not as straightforward.Comment: 1+13 pages. LaTeX. 3 Figures. Factor of 2N fixed to N for the IIA background. Minor changes to tex

Predicting Inter-Species Cross-Talk in Two-Component Signalling Systems

Phosphosignalling pathways are an attractive option for the synthetic biologist looking for a wide repertoire of modular components from which to build. We demonstrate that two-component systems can be used in synthetic biology. However, their potential is limited by the fact that host cells contain many of their own phosphosignalling pathways and these may interact with, and cross-talk to, the introduced synthetic components. In this paper we also demonstrate a simple bioinformatic tool that can help predict whether interspecies cross-talk between introduced and native two-component signalling pathways will occur and show both in vitro and in vivo that the predicted interactions do take place. The ability to predict potential cross-talk prior to designing and constructing novel pathways or choosing a host organism is essential for the promise that phosphosignalling components hold for synthetic biology to be realised

Surgical treatment of lung cancer in patients under 45 years of age

Aim. The aim of the study was to evaluate the characteristics and prognosis of radical surgical treatment in young patients under the age of 45 with lung cancer. Methods. We retrospectively analysed the data of 85 young patients and 211 older patients who underwent anatomical lung resections in Wroclaw Thoracic Surgery Centre. Results. Less lobectomies were performed (p=0.048), the incidence of carcinoid was significantly higher (p<0.0001), stage I of lung cancer was observed less frequently (p=0.023), the frequency of metastasis to subcarinal lymph nodes was higher (p=0.007), a bronchial stump was microscopically infiltrated more frequently, the complete resection was noted rarer (p=0.016) and 3-year survival rate of squamous cell carcinoma patients was worse in younger group (p=0.017). The statistical significance was not observed between the frequency of recurrences and overall survival. Conclusions. Lung cancer in younger patients seems to be more advanced at the time of surgery. It is probable that the group of younger patients with squamous cell carcinoma will require additional treatment after surgery