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Backgrounds: To investigate the changes of anterior eye segment with implantable collamer lens (ICL) under mesopic and photopic conditions. Method: Forty-seven eyes of myopic patients who underwent ICL V4c implantation were included. Three months after surgery, the pupil diameter (PD), dynamic vault, ACD (distance from the posterior corneal surface to the anterior lens surface), ACD-ICL (distance from the posterior corneal surface to the anterior ICL surface), and anterior chamber angle parameters were measured using the anterior segment optical coherence tomography (AS-OCT, Carl Zeiss AG, Germany) under completely mesopic (0 lx) and photopic (5290 lx) lighting conditions. Results: Compared with mesopic conditions, a significant decreased vault was detected in photopic conditions (486.7 ± 186.1 μm versus 643.5 ± 191.2 μm, p < 0.001), while the ACD-ICL increased significantly (2.54 ± 0.24 mm versus 2.37 ± 0.23 mm, p < 0.001). The pupil was smaller in photopic condition (2.66 ± 0.23 mm versus 5.62 ± 0.55 mm, p < 0.001). ACD didn't change(3.32 ± 0.24 mm versus 3.31 ± 0.22 mm, p = 0.079). The change of the vault was positively related to the changes of the PD (r2 = 0.301, p = 0.04). There were no statistical difference between the change of vault and the change of ACD-ICL (158.0 ± 58.1 μm versus 165.9 ± 65.3 μm, p = 0.320). Conclusion: When exposed to high intensity light after ICL surgery, the pupil constricted, vault decreased, ACA widened and ACD-ICL increased. All these changes were caused by the change of iris not the crystalline lens. [ABSTRACT FROM AUTHOR]

Background: Aggregations of cyanobacteria in lakes and reservoirs are commonly associated with surface blooms, but may also occur in the metalimnion as subsurface or deep chlorophyll maxima. Metalimnetic cyanobacteria blooms are of great concern when potentially toxic species, such as Planktothrix rubescens, are involved. Metalimnetic blooms of P. rubescens have apparently increased in frequency and severity in recent years, so there is a strong need to identify reservoir management options to control it. We hypothesized that P. rubescens blooms in reservoirs can be suppressed using selective withdrawal to maximize its export from the reservoir. We also expect that altering the light climate can affect the dynamics of this species. We tested our hypothesis in Rappbode Reservoir (the largest drinking water reservoir in Germany) by establishing a series of withdrawal and light scenarios based on a calibrated water quality model (CE-QUAL-W2). Results: The novel withdrawal strategy, in which water is withdrawn from a certain depth below the surface within the metalimnion instead of at a fixed elevation relative to the dam wall, significantly reduced P. rubescens biomass in the reservoir. According to the simulation results, we defined an optimal withdrawal volume to control P. rubescens blooms in the reservoir as approximately 10 million m3 (10% of the reservoir volume) during its bloom phase. The results also illustrated that P. rubescens growth can be most effectively suppressed if the metalimnetic withdrawal is applied in the early stage of its rapid growth, i.e., before the bloom occurs. In addition, our study showed that P. rubescens biomass gradually decreased with increasing light extinction and nearly disappeared when the extinction coefficient exceeded 0.55 m−1. Conclusions: Our study indicates the rise in P. rubescens biomass can be effectively offset by selective withdrawal as well as by reducing light intensity beneath the water surface. Considering the widespread occurrence of P. rubescens in stratified lakes and reservoirs worldwide, we believe the results will be helpful for scientists and managers working on other water bodies to minimize the negative impacts of this harmful cyanobacteria. Our model may serve as a transferable tool to explore local dynamics in other standing waters. [ABSTRACT FROM AUTHOR]

We have previously shown that in Arabidopsis the three enzymes of lower glycolysis namely phosphoglycerate mutase (PGAM), enolase and pyruvate kinase form a complex which plays an important role in tethering the mitochondria to the chloroplast. Given that the metabolism of these mutants, the complemented of pgam mutant and overexpression lines of PGAM were unclear, here, we present gas chromatography mass spectrometry-based metabolomics data of them alongside their plant growth phenotypes. Compared with wild type, both sugar and amino acid concentration are significantly altered in phosphoglycerate mutase, enolase and pyruvate kinase. Conversely, overexpression of PGAM could decrease the content of 3PGA, sugar and several amino acids and increase the content of alanine and pyruvate. In addition, the pgam mutant could not be fully complemented by either a nuclear target pgam, a side-directed-mutate of pgam or a the E.coli PGAM in term of plant phenotype or metabolite profiles, suggesting the low glycolysis complete formation is required to support normal metabolism and growth. Measurement(s) Metabolite profiling of Arabidopsis mutants of enzymes of lower glycolysis Technology Type(s) Gas chromatography–mass spectrometry Factor Type(s) Metabolite profiling of lower glycolysis Sample Characteristic - Organism Arabidopsis mutants of enzymes of lower glycolysis Sample Characteristic - Environment plant grow under 8 h light (22 °C)/16 h dark (18 °C) in growth chamber at a light intensity of 120–150 μmol m-2 s-1 Sample Characteristic - Location 2Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany [ABSTRACT FROM AUTHOR]

Aims: The intensification of grassland management can cause a loss of biodiversity via alteration of the structure and micro‐environmental conditions within the sward. The species richness of hay meadows protected within the Natura 2000 network is often endangered by high levels of fertilisation and relatedly, increased cutting frequency, which leads to decreased light availability for small plants and seedlings at ground level. The purpose of this study is to analyse how management practices and the interaction of fertilisation and cutting regime affect light distribution in grassland canopies as well as the growth of small plants. Location: South Germany. Methods: This was investigated by measuring the photosynthetically active radiation (PAR) and dry matter yield (DMY) of the first growth cycle over 2 years at two sites of a 5‐year‐old hay meadow trial. To calculate the relative light intensity, PAR was measured above the canopy and at ground level. Two factors, fertilisation (none, PK, NPK) and date of first cut (based on phenological stages), were manipulated. Results: Our results show that the date of the first cut had no influence on light availability during the first growth cycle, whereas fertilisation decreased light availability for small plants due to a denser canopy. Fertilisation increased the DMY of the first growth cycle significantly. We show that NPK fertilisation (35 kg N, 35 kg P2O5 and 120 kg K2O ha−1 a−1) decreased both the number and proportion of small plant species. Conclusion: NPK fertilisation can lead to a loss of biodiversity. These results are of relevance for the improvement and management of species‐rich hay meadows. Because of its effect on competition for light, the supply of plant‐available nitrogen is a key driver in obtaining or restoring biodiversity in species‐rich hay meadows. Therefore, careful site‐adapted fertilisation is a basic requirement in maintaining the ecological value of grassland. [ABSTRACT FROM AUTHOR]

This paper studies regional economic development on the municipality-level in Poland and Germany along the Oder–Neisse border. We use high-quality satellite night-time light intensity data as an innovative and comparable measure to proxy for overall economic activity on both sides of the border consistently over a long period of time (1992–2012). We use descriptive heat maps as well as regression analysis to investigate two aspects: first, how far is the economic convergence along the Polish-German border? Second, what effect does the distance to the border have on economic activity as measured with light emissions? Our findings suggest that convergence in overall activity across the border has been complete. Polish municipalities that used to be economically much weaker have caught up with those on the German side of the Oder and the Neisse rivers. As regards the importance of distance, we highlight different results for Germany and Poland. While distance to the border never mattered significantly for German regions, Polish municipalities closer to the border used to be substantially worse off in the early 1990s but caught up with regions further to the east by the end of the period of our analysis. [ABSTRACT FROM AUTHOR]

In view of the planned abandonment of routine beak-trimming in turkeys in Germany, two different blunting methods were evaluated at the "Education, Research and Demonstration Centre of Poultry and Small Animal Farming" in Kitzingen (Germany) and the effects on selected welfare indicators for non beak-trimmed turkeys were examined. Altogether 746 male B. U. T. 6 turkey chicks of the breeding company Moorgut Kartzfehn von Kameke GmbH & Co. KG, Bösel, Germany were housed. For the first five weeks the chicks were reared in twelve compartments with a stocking density of 11.8 kg/m2. For the actual examination during the fattening period (6.-21. live week), a total of 600 male turkeys were randomized to a total of 24 experimental compartments after the fifth week of life (planned stocking density: 51,9 kg/m²) and the respective blunting method was installed into the pan feeding system of the compartments. The following control and experimental groups were used: K1: beak-trimmed turkeys without blunting (n = 150 animals); K2: non beak-trimmed turkeys without blunting (n = 150 animals); V1: non beak-trimmed turkeys with screed grinding disc as blunting method (n = 150 animals) and V2: non beak-trimmed turkeys with metal grid disc (n = 150 animals). In 28-days rhythms the turkeys were scored, the beak was measured and the weight of the animals was recorded. In addition, data on indoor and outdoor climate such as light intensity, gaseous ammonia content, temperature and humidity was collected. In addition 12 randomly selected turkeys from each variant were slaughtered in Kitzingen after the 17th and 21st week of life, and their heads examined macroscopically and histologically at the Bavarian State Office for Health and Food Safety in Erlangen (Bavaria, Germany). There were significant differences (p = 0.05) between the experimental groups in the beak rating, concerning the length of the beak, the beak supernatant and the slaughter weight. Strong differences were found between the beak-trimmed and the non beak-trimmed turkeys. Significant (p = 0.05) differences were also noted between the two blunting methods, for example in the upper beak supernatant: with screed grinding disc 3.02 mm and with the metal grid disc 4.00 mm. With regard to the morphology of the beak, a significant higher abrasion was achieved with screed grinding discs without any injury to the tactile organ. [ABSTRACT FROM AUTHOR]

Abstract: The influence of light and temperature on the cylindrospermopsin (CYN) production of two Aphanizomenon flos-aquae strains, isolated from North-eastern German lakes, was investigated with semi-continuously growing cultures. A light gradient from 10 to 60μEm−2 s−1 in combination with temperatures of 16, 20, and 25°C was tested. CYN concentrations varied by a maximum factor of 2.7 in strain 10E9 with a significant decrease with increasing temperature. Strain 22D11 showed less pronounced changes, i.e. by a factor of 1.6, and without clear relationship to temperature. Reaction patterns of CYN production to changing light intensities are different at different temperatures. In both strains CYN concentrations increase significantly at 20°C between 10 and 60μEm−2 s−1, whereas they decrease significantly at 25°C in the same light gradient. The amount of synthesised CYN is not reflected by growth rates of the strains in a uniform manner. Nonetheless several temperature–light combinations which constitute physiological stress seem to trigger CYN production and particularly CYN release from cells. The lowest growth rate observed at 16°C and 60μEm−2 s−1 of strain 22D11 may reflect photoinhibition due to the lower temperature and related limited CO2-fixation. Under these conditions, extracellular CYN concentrations increased to 58% of total CYN, while the share of extracellular CYN of all other light and temperature regimes was 11–26%. From the results and the experimental design we conclude an active release of the toxin into medium to be more likely than mere leakage from cells. [Copyright &y& Elsevier]

Abstract: Morphological variations of Asterionella formosa were studied both in field samples from Bautzen Reservoir, Germany, and in culture experiments. It was observed that this diatom exhibited considerable variation in the number of cells per colony, ranging from unicells to colonies with more than 16 cells. The winter period of two consecutive years which differed with respect to ice- and snow cover were compared (1995: no ice cover; 1996: an ice cover lasting 4 months). A. formosa was obviously inedible for Daphnia in winter 1995 whereas in the same period in 1996 this species represented a main food source for Daphnia galeata, as was demonstrated by microscopic observation of the gut content of D. galeata during periods of Asterionella blooms. From feeding experiments with 14C-labelled A. formosa of different colony sizes and from microscopic observations of Daphnia feeding in a suspension of Asterionella colonies, I confirmed that only Asterionella colonies with up to 7 cells were effectively ingested by D. galeata. Above this threshold, the ingestion efficiency decreased to less than 30%. Steady-state populations of A. formosa in culture experiments showed a marked dependence on the number of cells per colony on light intensities. The mean colony size was usually less than 5 when light was limited (fell below a threshold of 20μEm−2 s−1), and greater than 8 when light intensities exceeded 110μEm−2 s−1. In Bautzen Reservoir, low light penetration owing to snow-covered ice in winter 1996 resulted, similar to culture experiments, in Asterionella colonies with 4 or less than 4 cells. Contrary to 1996, non-limited light penetration corresponded to 8-celled colonies in winter 1995. Light limitation during periods of ice cover should therefore be a strong environmental predictor of the colony size of A. formosa and, consequently, of the ingestion efficiency of a Daphnia population, thereby strongly modifying trophic interactions in pelagic food webs. [Copyright &y& Elsevier]