Quasi-point separation of variables for the Henon-Heiles system and a system with quartic potential

We examine the problem of integrability of two-dimensional Hamiltonian systems by means of separation of variables. The systematic approach to construction of the special non-pure coordinate separation of variables for certain natural two-dimensional Hamiltonians is presented. The relations with SUSY quantum mechanics are discussed.Comment: 11 pages, Late

Gene signature of the post-Chernobyl papillary thyroid cancer

Purpose: Following the nuclear accidents in Chernobyl and later in Fukushima, the nuclear community has been faced with important issues concerning how to search for and diagnose biological consequences of low-dose internal radiation contamination. Although after the Chernobyl accident an increase in childhood papillary thyroid cancer (PTC) was observed, it is still not clear whether the molecular biology of PTCs associated with low-dose radiation exposure differs from that of sporadic PTC. Methods: We investigated tissue samples from 65 children/young adults with PTC using DNA microarray (Affymetrix, Human Genome U133 2.0 Plus) with the aim of identifying molecular differences between radiation-induced (exposed to Chernobyl radiation, ECR) and sporadic PTC. All participants were resident in the same region so that confounding factors related to genetics or environment were minimized. Results: There were small but significant differences in the gene expression profiles between ECR and non-ECR PTC (global test, p < 0.01), with 300 differently expressed probe sets (p < 0.001) corresponding to 239 genes. Multifactorial analysis of variance showed that besides radiation exposure history, the BRAF mutation exhibited independent effects on the PTC expression profile; the histological subset and patient age at diagnosis had negligible effects. Ten genes (PPME1, HDAC11, SOCS7, CIC, THRA, ERBB2, PPP1R9A, HDGF, RAD51AP1, and CDK1) from the 19 investigated with quantitative RT-PCR were confirmed as being associated with radiation exposure in an independent, validation set of samples. Conclusion: Significant, but subtle, differences in gene expression in the post-Chernobyl PTC are associated with previous low-dose radiation exposure

Temporal and spatiotemporal autocorrelation of daily concentrations of Alnus, Betula, and Corylus pollen in Poland

The aim of the study was to determine the characteristics of temporal and space–time autocorrelation of pollen counts of Alnus, Betula, and Corylus in the air of eight cities in Poland. Daily average pollen concentrations were monitored over 8 years (2001–2005 and 2009–2011) using Hirst-designed volumetric spore traps. The spatial and temporal coherence of data was investigated using the autocorrelation and cross-correlation functions. The calculation and mathematical modelling of 61 correlograms were performed for up to 25 days back. The study revealed an association between temporal variations in Alnus, Betula, and Corylus pollen counts in Poland and three main groups of factors such as: (1) air mass exchange after the passage of a single weather front (30–40 % of pollen count variation); (2) long-lasting factors (50–60 %); and (3) random factors, including diurnal variations and measurements errors (10 %). These results can help to improve the quality of forecasting models

Protecting wound edges from infection using an Alexis wound retractor

Wstęp. Zakażenia ran operacyjnych towarzyszą ludzkości od zarania dziejów. Przez wieki były jedną z głównych przyczyn zgonów. Pomimo rozwoju wielu dziedzin życia, postęp w ich leczeniu nastąpił faktycznie w ciągu ostatnich stu siedemdziesięciu lat. Niemniej jednak problem zakażeń ran operacyjnych jest nadal aktualny pomimo szerokiego zastosowania działań profilaktycznych. Uważa się, że ilość tego rodzaju zakażeń jest jednym z najistotniej-szych wyznaczników rozwoju medycyny. Autorzy założyli, że zastosowanie jednorazowego retraktora ran Alexis zmniejszy ilość zakażeń ran operacyjnych, w szczególności u chorych wysokiego ryzyka. Materiał i metoda. W celu rozwiązania problemu badawczego zastosowano metodę badań reprezentacyjnych, a jako narzędzie badawcze posłużył arkusz analizy dokumentów. Autorzy przyjęli, że badanie będzie wiarygodne, gdy ryzyko zakażenia rany operacyjnej będzie odpowiednio duże. Chorzy, spełniający założone kryteria, zostali zakwalifikowani do dwóch losowo z kompletowanych grup. Obie grupy liczyły po 15 osób, przy czym wiek grupy badanej wahał się pomiędzy 54-83 lat, zaś grupy kontrolnej 57-86 lat. W grupie badanej stosowano retraktor, w grupie kontrolnej nie. Rana operacyjna była oceniana w trakcie hospitalizacji pacjenta codziennie, a po wy-pisaniu z oddziału okresowo do 30-ego dnia po operacji. W przypadku pojawienia się infekcji w ranie, została ona potwierdzona bada-niem mikrobiologicznym. Wyniki i wnioski. W oparciu o analizę wyników badań można stwierdzić, że u chorych z grupy podwyższonego ryzyka zastosowanie retraktora ran operacyjnych Alexis zmniejsza prawdopodobieństwo zakażenia rany operacyjnej, a skuteczna mechaniczna protekcja rany operacyjnej powinna stać się stałym elementem działań profilaktycznych zmierzających do ograniczenia ilości zakażeń ran operacyjny.Introduction. The infections of surgical wounds have been very much around since the beginnings of mankind. For ages they have been one of the predominant causes of death. Despite the fact that many aspects of life have undergone rapid developments, the progress in surgical wound treatment emerged during the last 170 years. Nevertheless, the problem of surgical wound infection is still a threat even despite many preventive actions. It is widely acknowledged that the number of those infections is one of the most crucial indicator of the development of medicine. The author has assumed that the use of a disposable Alexis wound retractor is going to decrease the number of surgical infections, especially among high-risk patients. The material and the method. In order to solve the research problem, the sampling procedure method was used. The research instrument was document analysis worksheet. The authors assumed that the re-search would be more credible if the risk of surgical wound infection is high enough. The patients who met the criteria were divided randomly into two groups. Both groups had 15 people; their ages varied from 54 to 83 in the sample group and from 57 to 86 in the control group. The retractor was used in the sample group and not in the control group. The surgical wounds were assessed each day while the patient stayed at the hospital, and after that periodically until 30 days after the operation. If the wound started showing indications of an infection, a microbiological test was run to confirm it. The results and conclusions. Judging by the analysis of the research results, one can conclude that the use of an Alexis surgical wound retractor on high-risk patients decreases the probability of a wound infection and the effective mechanical protection of surgical wounds should become a constant element of preventive actions aimed at limiting the number of surgical wound infections

Wheat-barley hybridization – the last forty years

Abstract Several useful alien gene transfers have been reported from related species into wheat (Triticum aestivum), but very few publications have dealt with the development of wheat/barley (Hordeum vulgare) introgression lines. An overview is given here of wheat 9 barley hybridization over the last forty years, including the development of wheat 9 barley hybrids, and of addition and translocation lines with various barley cultivars. A short summary is also given of the wheat 9 barley hybrids produced with other Hordeum species. The meiotic pairing behaviour of wheat 9 barley hybrids is presented, with special regard to the detection of wheat– barley homoeologous pairing using the molecular cytogenetic technique GISH. The effect of in vitro multiplication on the genome composition of intergeneric hybrids is discussed, and the production and characterization of the latest wheat/barley translocation lines are presented. An overview of the agronomical traits (b-glucan content, earliness, salt tolerance, sprouting resistance, etc.) of the newly developed introgression lines is given. The exploitation and possible use of wheat/barley introgression lines for the most up-to-date molecular genetic studies (transcriptome analysis, sequencing of flow-sorted chromosomes) are also discussed

The Effects of Activating Gender-Related Social Roles on Financial Risk-Taking

Previous studies observed differences between men and women in terms of their financial risk-taking. However, these differences may stem not only from the gender of the decision-maker but also from other factors, such as stereotypical gender social roles. Media content exposes both men and women to stereotypical portrayals of their gender, and this might temporarily activate thoughts related to their social roles. A question arises whether such activation might impact the way people make risky financial decisions. The present experimental study investigated whether temporarily activated gender-related social roles influence the risk-taking propensities of men and women (N = 319) in the context of gambling and investment choices. The results show that activating a stereotypically male social role (professional employee) made both men and women more prone to take financial risks relative to a control condition. Furthermore, activating a stereotypically female social role (homemaker) lowered the propensity to take financial risks in both genders for the investment domain and in women only for the gambling domain. This study contributes to the literature on gender differences in economic behavior by showing that researchers should not overlook sociocultural factors

FRA2A is a CGG repeat expansion associated with silencing of AFF3

Folate-sensitive fragile sites (FSFS) are a rare cytogenetically visible subset of dynamic mutations. Of the eight molecularly characterized FSFS, four are associated with intellectual disability (ID). Cytogenetic expression results from CGG tri-nucleotide-repeat expansion mutation associated with local CpG hypermethylation and transcriptional silencing. The best studied is the FRAXA site in the FMR1 gene, where large expansions cause fragile X syndrome, the most common inherited ID syndrome. Here we studied three families with FRA2A expression at 2q11 associated with a wide spectrum of neurodevelopmental phenotypes. We identified a polymorphic CGG repeat in a conserved, brain-active alternative promoter of the AFF3 gene, an autosomal homolog of the X-linked AFF2/FMR2 gene: Expansion of the AFF2 CGG repeat causes FRAXE ID. We found that FRA2A-expressing individuals have mosaic expansions of the AFF3 CGG repeat in the range of several hundred repeat units. Moreover, bisulfite sequencing and pyrosequencing both suggest AFF3 promoter hypermethylation. cSNP-analysis demonstrates monoallelic expression of the AFF3 gene in FRA2A carriers thus predicting that FRA2A expression results in functional haploinsufficiency for AFF3 at least in a subset of tissues. By whole-mount in situ hybridization the mouse AFF3 ortholog shows strong regional expression in the developing brain, somites and limb buds in 9.5-12.5dpc mouse embryos. Our data suggest that there may be an association between FRA2A and a delay in the acquisition of motor and language skills in the families studied here. However, additional cases are required to firmly establish a causal relationship

Knitting for heart valve tissue engineering.

Knitting is a versatile technology which offers a large portfolio of products and solutions of interest in heart valve (HV) tissue engineering (TE). One of the main advantages of knitting is its ability to construct complex shapes and structures by precisely assembling the yarns in the desired position. With this in mind, knitting could be employed to construct a HV scaffold that closely resembles the authentic valve. This has the potential to reproduce the anisotropic structure that is characteristic of the heart valve with the yarns, in particular the 3-layered architecture of the leaflets. These yarns can provide oriented growth of cells lengthwise and consequently enable the deposition of extracellular matrix (ECM) proteins in an oriented manner. This technique, therefore, has a potential to provide a functional knitted scaffold, but to achieve that textile engineers need to gain a basic understanding of structural and mechanical aspects of the heart valve and in addition, tissue engineers must acquire the knowledge of tools and capacities that are essential in knitting technology. The aim of this review is to provide a platform to consolidate these two fields as well as to enable an efficient communication and cooperation among these two research areas

Landscape structure affects the prevalence and distribution of a tick-borne zoonotic pathogen

Background Landscape structure can affect pathogen prevalence and persistence with consequences for human and animal health. Few studies have examined how reservoir host species traits may interact with landscape structure to alter pathogen communities and dynamics. Using a landscape of islands and mainland sites we investigated how natural landscape fragmentation affects the prevalence and persistence of the zoonotic tick-borne pathogen complex Borrelia burgdorferi(sensu lato), which causes Lyme borreliosis. We hypothesized that the prevalence of B. burgdorferi (s.l.) would be lower on islands compared to the mainland and B. afzelii, a small mammal specialist genospecies, would be more affected by isolation than bird-associated B. garinii and B. valaisiana and the generalist B. burgdorferi (sensu stricto). Methods Questing (host-seeking) nymphal I. Ricinus ticks (n = 6567) were collected from 12 island and 6 mainland sites in 2011, 2013 and 2015 and tested for B. burgdorferi(s.l.). Deer abundance was estimated using dung transects. Results The prevalence of B. burgdorferi (s.l.) was significantly higher on the mainland (2.5%, 47/1891) compared to island sites (0.9%, 44/4673) (P < 0.01). While all four genospecies of B. burgdorferi (s.l.) were detected on the mainland, bird-associated species B. garinii and B. valaisiana and the generalist genospecies B. burgdorferi(s.s.) predominated on islands. Conclusion We found that landscape structure influenced the prevalence of a zoonotic pathogen, with a lower prevalence detected among island sites compared to the mainland. This was mainly due to the significantly lower prevalence of small mammal-associated B. afzelii. Deer abundance was not related to pathogen prevalence, suggesting that the structure and dynamics of the reservoir host community underpins the observed prevalence patterns, with the higher mobility of bird hosts compared to small mammal hosts leading to a relative predominance of the bird-associated genospecies B. garinii and generalist genospecies B. burgdorferi (s.s.) on islands. In contrast, the lower prevalence of B. afzelii on islands may be due to small mammal populations there exhibiting lower densities, less immigration and stronger population fluctuations. This study suggests that landscape fragmentation can influence the prevalence of a zoonotic pathogen, dependent on the biology of the reservoir host

Using Light to Improve Commercial Value

The plasticity of plant morphology has evolved to maximize reproductive fitness in response to prevailing environmental conditions. Leaf architecture elaborates to maximize light harvesting, while the transition to flowering can either be accelerated or delayed to improve an individual's fitness. One of the most important environmental signals is light, with plants using light for both photosynthesis and as an environmental signal. Plants perceive different wavelengths of light using distinct photoreceptors. Recent advances in LED technology now enable light quality to be manipulated at a commercial scale, and as such opportunities now exist to take advantage of plants' developmental plasticity to enhance crop yield and quality through precise manipulation of a crops' lighting regime. This review will discuss how plants perceive and respond to light, and consider how these specific signaling pathways can be manipulated to improve crop yield and quality