Climate change and its effect on agriculture, water resources and human health sectors in Poland

Multi-model ensemble climate projections in the ENSEMBLES Project of the EU allowed the authors to quantify selected extreme-weather indices for Poland, of importance to climate impacts on systems and sectors. Among indices were: number of days in a year with high value of the heat index; with high maximum and minimum temperatures; length of vegetation period; and number of consecutive dry days. Agricultural, hydrological, and human health indices were applied to evaluate the changing risk of weather extremes in Poland in three sectors. To achieve this, model-based simulations were compared for two time horizons, a century apart, i.e., 1961–1990 and 2061–2090. Climate changes, and in particular increases in temperature and changes in rainfall, have strong impacts on agriculture via weather extremes – droughts and heat waves. The crop yield depends particularly on water availability in the plant development phase. To estimate the changes in present and future yield of two crops important for Polish agriculture i.e., potatoes and wheat, some simple empirical models were used. For these crops, decrease of yield is projected for most of the country, with national means of yield change being: –2.175 t/ha for potatoes and –0.539 t/ha for wheat. Already now, in most of Poland, evapotranspiration exceeds precipitation during summer, hence the water storage (in surface water bodies, soil and ground) decreases. Summer precipitation deficit is projected to increase considerably in the future. The additional water supplies (above precipitation) needed to use the agro-potential of the environment would increase by half. Analysis of water balance components (now and in the projected future) can corroborate such conclusions. As regards climate and health, a composite index, proposed in this paper, is a product of the number of senior discomfort days and the number of seniors (aged 65+). The value of this index is projected to increase over 8-fold during 100 years. This is an effect of both increase in the number of seniors (over twofold) and the number of senior-discomfort days (nearly fourfold)

Electrical switching of a chiral lasing from polariton condensate in a Rashba-Dresselhaus regime

Efficient optical classical and quantum information processing imposes on light novel requirements: chirality with low threshold non-linearities. In this work we demonstrate a chiral lasing from an optical modes due to emerging photonic Rashba-Dresselhaus spin-orbit coupling (SOC). For this purpose we developed a new electrically tunable device based on an optical cavity filled with birefringent liquid crystal (LC) and perovskite crystals. Our novel method for the growth of single crystals of CsPbBr$_3$ inorganic perovskite in polymer templates allows us to reach a strong light-matter coupling regime between perovskite excitons and cavity modes, and induce polariton condensation. The sensitivity of the LC to external electric fields lets us to tune the condensate energy in situ and induce synthetic SOC. This shapes the condensate between a single linearly polarized or two circularly polarized separated in momentum, emitting coherent light. The difference in the condensation thresholds between the two SOC regimes can be used to switch on and off the chiral condensate emission with a voltage.Comment: 8 pages, 5 figure

Glutathione-Related Antioxidant Defense System in Elderly Patients Treated for Hypertension

The purpose of this study was to analyze glutathione antioxidant defense system in elderly patients treated for hypertension. Studies were carried out in the blood collected from 18 hypertensive and 15 age- and sex-matched controls, all subjects age over 60. Hypertensives were on their usual antihypertensive treatment at the time of blood collection. The concentration of glutathione (GSH) in whole blood and activities of glutathione peroxidase (GPx-1), glutathione transferase (GST), and glutathione reductase (GR) in erythrocytes were measured. The data from patients and controls were compared using independent-samples t test. P value of 0.05 and less was considered statistically significant. We observed increased glutathione-related antioxidant defense in treated hypertensive elderly patients (HT) when compared with healthy controls (C). Mean GSH concentration was significantly higher in HT when compared with C: 3.1 ± 0.29 and 2.6 ± 0.25 mmol/L, respectively, P < 0.001. Mean activity of GR was significantly higher in HT group if compared with C: 83.4 ± 15.25 U/g Hb versus 64.2 ± 8.26 U/g Hb, respectively, P < 0.001. Mean activity of GST was significantly higher in HT group compared with C: 3.0 ± 0.60 mmol CDNB-GSH/mgHb/min and 2.6 ± 0.36 mmol CDNB-GSH/mgHb/min, respectively, P < 0.05. No difference in GPx activity was observed between two groups. These results show that glutathione-related antioxidant defense system was enhanced in elderly hypertensive patients treated for their conditions. This suggests important role of glutathione system in blood pressure regulation. Alterations in concentration and activity of antioxidants observed during antihypertensive medication are likely to be related to the effect of the treatment on NO bioavailability

Hepatitis C virus quasispecies in chronically infected children subjected to interferon–ribavirin therapy

Accumulating evidence suggests that certain features of hepatitis C virus (HCV), especially its high genetic variability, might be responsible for the low efficiency of anti-HCV treatment. Here, we present a bioinformatic analysis of HCV-1a populations isolated from 23 children with chronic hepatitis C (CHC) subjected to interferon–ribavirin therapy. The structures of the viral quasispecies were established based on a 132-amino-acid sequence derived from E1/E2 protein, including hypervariable region 1 (HVR1). Two types of HCV populations were identified. The first type, found in non-responders, contained a small number of closely related variants. The second type, characteristic for sustained responders, was composed of a large number of distantly associated equal-rank variants. Comparison of 445 HVR1 sequences showed that a significant number of variants present in non-responding patients are closely related, suggesting that certain, still unidentified properties of the pathogen may be key factors determining the result of CHC treatment

No systematic effects of sampling direction on climate-growth relationships in a large-scale, multi-species tree-ring data set

Ring-width series are important for diverse fields of research such as the study of past climate, forest ecology, forest genetics, and the determination of origin (dendro-provenancing) or dating of archaeological objects. Recent research suggests diverging climate-growth relationships in tree-rings due to the cardinal direction of extracting the tree cores (i.e. direction-specific effect). This presents an understudied source of bias that potentially affects many data sets in tree-ring research. In this study, we investigated possible direction-specific growth variability based on an international (10 countries), multi-species (8 species) tree-ring width network encompassing 22 sites. To estimate the effect of direction-specific growth variability on climate-growth relationships, we applied a combination of three methods: An analysis of signal strength differences, a Principal Component Gradient Analysis and a test on the direction-specific differences in correlations between indexed ring-widths series and climate variables. We found no evidence for systematic direction-specific effects on tree radial growth variability in high-pass filtered ring-width series. In addition, direction-specific growth showed only marginal effects on climate-growth correlations. These findings therefore indicate that there is no consistent bias caused by coring direction in data sets used for diverse dendrochronological applications on relatively mesic sites within forests in flat terrain, as were studied here. However, in extremely dry, warm or cold environments, or on steep slopes, and for different life-forms such as shrubs, further research is advisable.</p

Rozwiązanie analityczne dla stożkowych kropek kwantowych

In the paper, an analytical method of the solution of a governing nonlinear eigenproblem is proposed. It can be directly applied into analysis of axisymmetric conical quantum dots embedded in a matrix. The method is based on the use of variational formulation combined with the method of the Rayleigh quotient and the series expansions. In order to explain the form of the series expansions (the Bessel and sine series), the analytical solutions for quantum dots are demonstrated and discussed. The solved example shows the efficiency of the method.W pracy zaproponowano analityczną metodę do rozwiązania nieliniowego problemu własnego. Może ona być bezpośrednio zastosowana do analizy osiowosymetrycznych stożkowych kropek kwantowych osadzonych w osnowie. Polega na wykorzystaniu wariacyjnego sformułowania w połączeniu z metodą Rayleigha i rozwinięciem w szereg. Przedstawiono i przeanalizowano analityczne rozwiązania dla kropek kwantowych z wykorzystaniem rożnych form rozwinięć w szereg (Bessela i Fouriera). Rozwiązany przykład pokazuje skuteczność przedstawionej metody

Nutritional status of frail elderly

Introduction: Growing population of elderly requires effective medical diagnostics and help. Criteria developed by Fried et al. are most often used for the diagnosis of the frailty syndrome. An inherent element of frailty syndrome is malnu-trition. Malnutrition results from inadequate food supply, coexistence of acute and chronic diseases. Effective nutritional interventions conducted on frail older persons can prevent them from developing the frailty syndrome. Review: The prevalence of frailty in elders is 17% moreover 42.3% are prefrail. There are many scales designed to identify frailty syndrome, but the most common is the classification of Fried et al. Malnutrition is a common state in frail elderly. Basic questionnaire, which is used to diagnose malnutrition, is MNA (Mini-Nutritional Assessment). Mini-Nutritional Assessment Short-Form (MNA-SF) and Malnutrition Universal Screening Tool (MUST) also can be used. Sarcopenia, which is defined as reduced muscle mass and strength and impaired muscle performance, significantly contribute to the development of frailty. Many studies have shown that an effective method in the preventing of sarcopenia is protein supplementation. Other beneficial lifestyle and diet changes, which can help prevent the development of frailty syndrome, are adherence to the Mediterranean diet, appro-priate intake of carotenoids, vitamin E, selenium and zinc. Another important protective factor is vitamin D levels. Low serum 25(OH)D is strongly associated with frailty. Conclusions: From a nutritional point of view adherence to a Mediterranean-style diet, sufficient intake of protein, micronutrients and vitamin D, as well as regular moderate physical activity, can be crucial in the preventing of the frailty syndrome

Strength calculations of a diesel engine high-pressure nozzle

Charakterystyczną cechą rozwijających się układów zasilania silników o zapłonie samoczynnym jest bardzo wysokie ciśnienie wtrysku paliwa osiągające obecnie wartość 200MPa. Prognozowany jest dalszy wzrost tego ciśnienia. W pracy przedstawiono wytrzymałościowe obliczenia rozpylacza obciążonego takim i wyższym ciśnieniem osiągającym wartość 300MPa. Na podstawie tych obliczeń stwierdzono, że ciśnienie wtrysku wynoszące 200MPa, jest granicznym z punktu widzenia wytrzymałości rozpylacza. Zwiększenie tego ciśnienia powoduje niebezpieczny wzrost naprężeń i przy osiągnięciu ciśnienia około 300MPa może nastąpić uszkodzenie studzienki rozpylacza.Advanced diesel engine fuel injection systems are characterised by very high injection pressure reaching 200 MPa now. A further pressure increase is still anticipated. Strength calculations of a nozzle operating at such pressure (and higher - equal to 300 MPa) are presented. On the basis of the results of these calculations, it has been found that the injection pressure equal to approx. 200 MPa is a limiting value from the viewpoint of the nozzle resistance. An increase in the pressure is followed by an increase in stresses and can cause a damage of a blind hole at the pressure of approx. 300 MPa

Frequency of occurrence, death rate and risk factors of delirium Influence of place of residence on nutrition in the elderly

Wstęp. Właściwe odżywianie, niezależnie od wieku człowieka, jest jednym z głównych czynników decydujących prawidłowym funkcjonowaniu organizmu. Może opóźnić naturalne, postępujące z wiekiem z różną intensywnością procesy starzenia się. Materiał i metody. Badania przeprowadzono wśród 100 osób w starszym wieku będących pod opieką Poradni Geriatrycznej Szpitala Uniwersyteckiego im. dr. A. Jurasza w Bydgoszczy oraz wśród pensjonariuszy Domów Pomocy Społecznej w Bydgoszczy i w Koronowie. Do badań użyto standaryzowanego kwestionariusza - skali Mini Nutritional Assessment (MNA) - oraz ankiety zawierającej dane socjo-demograficzne. Badanych podzielono na trzy grupy w zależności od sposobu zamieszkiwania: mieszkający samotnie, z rodziną, pensjonariusze Domu Pomocy Społecznej (DPS). Wyniki. Średnia wieku dla kobiet wynosiła 80 lat (przedział wieku 65-94 lata), a dla mężczyzn 76 lat (przedział wieku 66-92 lata). Największy odsetek badanych stanowiły osoby, które zamieszkiwały w DPS (54% respondentów). Z rodziną mieszkało 29 osób, a 17 mieszkało samotnie. Spośród badanych najwięcej osób cechowało się ryzykiem niedożywienia (60% respondentów). Dobry stan odżywienia cechował 36 badanych, a 4 osoby były niedożywione. Osoby, które mieszkały z rodziną, charakteryzowały się dobrym stanem odżywienia, a osoby mieszkające w DPS wykazywały ryzyko niedożywienia. Wnioski. Wykazano zależność między miejscem zamieszkania osób badanych a stanem odżywienia. Osoby mieszkające z rodziną były lepiej odżywione, natomiast osoby badane mieszkające w DPS wykazywały ryzyko niedożywienia.Background. Balanced diet (proper nutrition) independently of age, is one of the main factors which are essential for good health. Ageing affects people in different ways, however a balanced diet can help to minimize its effects. Material and methods. The study included 100 elderly patients of the geriatric clinic in Jurasz hospital, Bydgoszcz and pensioners of nursing homes in Bydgoszcz and Koronowo. In the study the Mini Nutritional Assessment (MNA) was used as well as a questionnaire with sociodemographic data. The respondents were divided into three groups on the basis of residence: people living with relatives, people living alone and pensioners of nursing homes. Results. Women were between 65 and 94 years of age and men between 66 and 92. Mean age of women was 80 and of men it was 76. Fifty four percent of respondents were pensioners of nursing homes, 29% lived with relatives and 17% lived alone. As many as 60% of respondents were at risk of malnutrition. Thirty six respondents were well-nourished and 4 were malnourished. Respondents living with relatives were well nourished and the pensioners of nursing homes were at risk of malnutrition. Conclusions. There is statistically significant difference between the elderly sharing residence with relatives or at nursing homes and nutrition. The study shows that people living with relatives are well nourished and pensioners of nursing homes are at risk of malnutrition