Autecology of Oocardium stratum Naeg. and CaCO3precipitation of autotrophic biofilms in travertine rivulets

Das Vorkommen der seltenen Zieralge Oocardium stratum, ist ausschließlich auf aktive Tuffstandorte beschränkt. Oocardium stratum bildet Gallertscheiden aus, an denen sich CaCO3 ablagert. Die stecknadelkopfgroßen, hellgrünen Kolonien weisen einen Durchmesser von 0.5 bis 2.0 mm auf. Da die Autökologie dieses Organismus bisher kaum erforscht war, untersuchten wir im ersten Teil unserer Studie die Saisonalität und den Einfluss von Umweltvariablen auf das Vorkommen von Oocardium stratum. Zu diesem Zweck beobachteten wir mittels wöchentlicher Mikro- und Makrokartierung die algenbewachsene Tuffoberfläche. Ebenso wurden wöchentlich die Wasserchemie und die Strahlungsbedingungen aufgenommen. Der zweite Teil der Studie beschäftigt sich mit der Sukzession von autotrophen Biofilmen, die O. stratum aufweisen, und der damit verbundenen Kalziumkarbonat-Abscheidung. Hierfür installierten wir aufgeraute Objektträger als künstliches Substrat, die zwischen 3 und 12 Wochen an den Versuchsstellen exponiert waren. Der abgekratzte Biofilm wurde anschließend auf den gesamten Chlorophyll-a Gehalt, den CaCO3-Anteil und mittels HPLC auf die Pigmentverteilung hin untersucht. Die Studie wurde an einem Quellbach in Lunz/See (Niederösterreich) über 17 Monate hinweg durchgeführt. Umweltvariablen wurden wöchentlich und im Winter 14-tägig gemessen. Biofilm und Kalziumcarbonat wurden ebenfalls 14-tägig besammelt. Im Zuge der Autökologiestudie wurde O. stratum das ganze Jahr hindurch an der Tuffquelle gefunden. Das Vorkommen der Kolonien erreichte ein Maximum im Hochsommer während der Monate Juli und August. Wiederholte Makrokartierungen mit einer Oberfläche von 750 cm2 an drei Spots in der Travertinquelle, zeigten ein Maximum von O. stratum überzogenem Tuff im August mit einer Bedeckung von 31%. Zwei kleinere Maxima zeigten sich im Frühsommer und Spätherbst mit 10% O. stratum - Bedeckung. Dicke Matten von Diatomeen, dominiert von Cymbella minuta, zeigten sich im Frühling, Herbst und Winter mit mehr als 74% Tuffbedeckung an den untersuchten Spots. Eine Mikrokartierung mit einer Oberfläche von 25.5 mm2 wurde ebenfalls an einer Stelle der Tuffquelle durchgeführt und zeigte die gleichen Ergebnisse. Die Redundanzanalyse zeigte Wassertemperatur und Bikarbonatgehalt als treibende Hauptfaktoren an, die das Vorkommen und das Wachstum von O. stratum kontrollieren. Optimale Wachstumsbedingungen wurden bei einer Alkalinität von 4.6-4.7 mmol L-1 und einer Wassertemperatur von 13 °C beobachtet. Die Parameter Belichtung, Nitrat und Kohlendioxid zeigten einen negativen Zusammenhang zur O. stratum Biomasse, hingegen einen positiven zum Diatomeen Vorkommen. Andere Umweltvariablen wie Ionengehalt oder gelöster reaktiver Phosphor hatte keinen signifikanten Einfluss auf das Vorkommen von O. stratum. In Quellnähe war die Niederschlagsrate von CaCO3 signifikant niedriger als an weiter quellabwärts gelegenen Untersuchungsstellen. Der Grund hierfür liegt am deutlich höheren freien CO2-Gehalt und dem niedrigeren pH- Wert in Quellnähe. Die CaCO3-Niederschlagsrate war im Sommer am höchsten. Die Menge an CaCO3 in Quellnähe war in beiden Untersuchungsjahren annähernd konstant und zeigte keine Zuwächse im zweiwöchigen Messabstand. Die quellabwärts gelegenen Untersuchungsstellen zeigten allerdings eine eindeutige positive zweiwöchig gemessene Niederschlagsrate, die von 5 - 27.5 mg cm-2 reichte. Die Chlorophyll-a Rate lag an allen Untersuchungsstellen zwischen 0.07 - 3.9 µg cm-2. Die Objektträger wurden zuerst von dicken Diatomeen-Matten besiedelt, dominiert von Cymbella minuta. Ein geringer Anteil an kokkenähnlichen Cyanobacterien konnte mikoskopisch und mittels HPLC nachgewiesen werden. Erst nachdem sich eine raue Kalkschicht niedergeschlagen hatte, war auch O. stratum auf den Objektträgern nachzuweisen. Nach etwa 6-7 Wochen waren die O. stratum-Kolonien auch makroskopisch sichtbar. Die Verteilung der Taxa gemittelt über alle Untersuchungsstellen und Aufnahmen zeigte, dass 77% der Algenbiomasse von Diatomeen stammen, 20% konnten O. stratum zugeordnet werden und 3% der Algenbiomassen waren Cyanobacterien. Diatomeen wiesen einen negativen Zusammenhang zur CaCO3-Niederschlagsrate auf, wohingegen Cyanobacterien einen geringfügig positiven Zusammenhang zeigten und O. stratum eine stark positive Übereinstimmung mit dem CaCO3-Niederschlag anzeigte. Unsere Resultate weisen auf eine Induzierung des Kalziumkarbonatniederschlages durch O. stratum hin; eine aktive, photosynthese-getriebene Kalkabscheidung durch O. stratum ist aber auszuschließen. Biomasse von O. stratum und gefälltes Kalziumkarbonat reagieren auf den chemischen, quellabwärtsgerichteten Gradienten und auf saisonale Veränderungen parallel. Dadurch ist es schwer zu unterscheiden, ob O. stratum die Fällung von CaCO3 erhöht oder ob beide, die O. stratum Biomasse und der CaCO3-Niederschlag, hauptsächlich durch den quellabwärts gerichteten chemischen Gradienten und durch saisonale Veränderungen kontrolliert werden.The rare calcifying desmid Oocardium stratum occurs exclusively on active travertine habitats; the macroscopic colonies form hemispherical structures with a diameter of 0.5 to 2.0 mm. Because autecology of this organism is still poorly understood, the first part of our study focused on its seasonal development and related various environmental factors to the occurrence and biomass of Oocardium. The second central theme of the study was the succession of photoautotrophic biofilms with a special focus on Oocardium stratum. For this we installed frosted glass slides as artificial substrata, which were exposed between 3 to 12 weeks. The study was conducted in a rivulet in Lunz/See (Lower Austria) for 17 months. Environmental variables were on a weekly (growing season) to monthly (winter season) basis; biofilm and precipitated tufa were sampled biweekly. The Autecology study resulted that Oocardium colonies were found throughout the whole year with maximum abundances during the mid summer months July and August. Repeated macromapping of three travertine spots with a size of 750 cm2 each showed a maximum Oocardium cover of 31 % in August. Two smaller maxima occurred in early summer and late autumn with about 10 % cover. Diatom mats, dominated by Cymbella minuta, occurred in spring, autumn and winter with more than 74 % of cover observed on macromapping spots. Micromapping was done at a single area covering 25.5 mm2 and revealed the same results. Redundancy analysis revealed water temperature and bicarbonate content as the main structuring factors, which control occurrence and growth of Oocardium. Optimal growth conditions appeared at an alkalinity of 4.6-4.7 mmol L-1 and water temperatures of 13 °C. Site openness, nitrate and carbon dioxide availability were inversely related to Oocardium biomass, but more connected to diatoms occurrence. Other environmental factors like total ions content or soluble reactive phosphorus had no significant influence on Oocardium stratum occurrence. The seasonal succession of Oocardium and diatom mats in limestone precipitating springs causes a typical sequence pattern of travertine layers, which can be recognised already with blank eyes. We found a significantly lower precipitation rate near the spring because of higher free CO2 amounts and higher pH levels than downstream. Precipitation was also higher in summer than in colder seasons. The biweekly precipitation of calcium carbonate near spring barely showed a positive rate. The amount of precipitated CaCO3 near spring was in both years nearly constant without a clear accession. However further downstream situated spots showed a clear positive biweekly precipitation rate, which ranged from 5 mg cm-2 up to 27.5 mg cm-2. The biweekly Chlorophyll a rate ranged at all spots from 0.07 µg cm-2 up to 3.9 µg cm-2. The colonization of the glass slides started with the growth of diatoms and after the successfully development of a constant rough travertine layer, Oocardium colonies followed. The O. stratum colonies were after 6-7 weeks macroscopically visible and its biomass was higher in summer than in autumn and spring. The diatom mats on frosted glass slides were also dominated by Cymbella minuta; only smaller amounts of coccoid Cyanobacteria could be detected. The distribution of taxa for the mean of all sites and dates showed that 77 % of the algae biomass were diatoms, 20 % could be related to O. stratum and 3% comprised Cyanobacteria. Diatoms were negatively related to precipitation, whereas Cyanobacteria were slightly positively and O. stratum biomass was strongly coinciding with carbonate precipitation. From our results, we assume an induction of carbonate precipitation by O. stratum, but no active deposition due to photosynthesis. O. stratum biomass and the amount of precipitation showed parallel reactions to downstream gradients and to the seasonal changes. We therefore could not distinguish, if O. stratum increases the precipitation or if both, precipitation and O. stratum are mainly controlled by downstream chemical gradients and seasonal changes

Why do patients having coronary artery bypass grafts have different costs or length of stay? : An analysis across ten European countries

We analyse variations in costs or lengths of stay (LoS) for 66,587 patients from ten European countries receiving a coronary artery bypass graft (CABG) procedure. In five of these countries, variations in cost are analysed using log-linear models. In the other five countries, negative binomial regression models are used to explore variations in LoS. We compare how well each country’s Diagnosis Related Group (DRG) system and a set of patient-level characteristics explain these variations. The most important explanatory factors are the total number of diagnoses and procedures, although no clear effects are evident for our CABG-specific diagnostic and procedural variables. Wound infections significantly increase length of stay and costs in all countries. There is no evidence that countries using larger numbers of DRGs to group CABG patients were better at explaining variations in cost or LoS. However, refinements to the construction of DRGs to group CABG patients might recognise first and subsequent CABGs or other specific surgical procedures, such as multiple valve repair

Comparative grading scales, statistical analyses, climber descriptors and ability grouping: International Rock Climbing Research Association position statement

The research base for rock climbing has expanded substantially in the past 3 decades as worldwide interest in the sport has grown. An important trigger for the increasing research attention has been the transition of the sport to a competitive as well as recreational activity and the potential inclusion of sport climbing in the Olympic schedule. The International Rock Climbing Research Association (IRCRA) was formed in 2011 to bring together climbers, coaches and researchers to share knowledge and promote collaboration. This position statement was developed during and after the 2nd IRCRA Congress which was held in Pontresina, in September 2014. The aim of the position statement is to bring greater uniformity to the descriptive and statistical methods used in reporting rock climbing research findings. To date there is a wide variation in the information provided by researchers regarding the climbers’ characteristics and also in the approaches employed to convert from climbing grading scales to a numeric scale suitable for statistical analysis. Our paper presents details of recommended standards of reporting that should be used for reporting climber characteristics and provides a universal scale for the conversion of climbing grades to a number system for statistical analysis

Urinary Excretion of Aluminium and Silicon in Secondary Progressive Multiple Sclerosis

Background: Progressive multiple sclerosis is a chronic autoimmune condition of unknown aetiology and few therapeutic options. Human exposure to aluminium has been linked with multiple sclerosis and affected individuals are known to excrete unusually high amounts of aluminium in their urine. Silicon-rich mineral waters facilitate the removal of aluminium from the body in urine and herein we have tested their efficacy in affecting urinary excretion of aluminium in individuals diagnosed with secondary progressive multiple sclerosis (SPMS). Methods: Urinary excretion of aluminium and silicon, measured using transversely-heated graphite furnace atomic absorption spectrometry, was determined in 15 individuals diagnosed with SPMS over 24 weeks, a 12 week baseline period (control) followed by a 12 week treatment period, during which individuals consumed up to 1.5 L of a silicon-rich mineral water every day. Findings: Individuals with SPMS excreted high amounts of aluminium during the baseline period (135.2 nmol/mmol Crt (70.3–222.2, n = 180) and females excreted significantly more aluminium than males. Regular drinking of a silicon-rich mineral water increased the urinary excretion of aluminium significantly (349.0 nmol/mmol Crt (231.7–524.7, n = 180; three-way ANOVA, F1,13 = 59.17, p-value = 0.000003) relative to the baseline period. The majority of individuals, 14 out of 15, excreted more aluminium (μmol/24 h) following drinking of a silicon-rich mineral water (independent-test, p < 0.05). Silicon-rich mineral waters may be an effective and non-invasive therapy for the removal of aluminium from the body of individuals with SPMS

Inflammatory and coagulatory parameters linked to survival in critically ill children with sepsis

Abstract Background Sepsis is associated with a deflection of inflammatory and coagulative parameters, since some clotting factors are known to be involved in the host’s defense against infection and inflammation. These parameters could play a crucial role in the course of sepsis and be used as prognostic markers in critically ill children. Methods A total of 250 critically ill pediatric patients diagnosed with sepsis were retrospectively analyzed to identify routinely measured predictors for in-hospital mortality at the peak level of C-reactive protein. Those parameters entered multivariate logistic regression analysis as well as a decision tree for survival. Results Multivariate logistic regression analysis revealed fibrinogen, platelets and activated partial thromboplastin time (aPTT) at the peak level of C-reactive protein to be predictors for survival (p = 0.03, p = 0.01 and p = 0.02, respectively). An increase in fibrinogen and platelets is linked to survival, whereas an aPTT prolongation is associated with higher mortality; adjusted odds ratios (95% CI) for an increase of 100 mg/dl in fibrinogen are 1.35 (1.04–1.82) per 50 G/l platelets 1.94 (1.3–3.29) and 0.83 (0.69–0.96) for an aPTT prolongation of 10 s. Decision tree analysis shows that a fibrinogen level below 192 mg/dl (90.9% vs. 13% mortality) is most distinctive in non-survivors. Conclusions High levels of fibrinogen and platelets as well as a non-overshooting aPTT are associated with a higher survival rate in pediatric patients with diagnosed sepsis. In particular, hypofibrinogenemia is distinctive for a high mortality rate in septic critically ill children

Pesticide contamination and associated risk factors at public playgrounds near intensively managed apple and wine orchards

BACKGROUND: Pesticide levels are generally monitored within agricultural areas, but are commonly not assessed at public places. To assess possible contamination of non-target areas, 71 public playgrounds located next to intensively managed apple and wine orchards were selected in four valleys of South Tyrol (northern Italy). Further, the impact of environmental site characteristics on the number and concentration of pesticides was assessed. Grass samples from the selected playgrounds were collected and screened for 315 pesticide residues using standard gas chromatography and mass spectrometry. RESULTS: Nearly half of the playgrounds (45%) were contaminated by at least one pesticide and a quarter (24%) by more than one. Eleven of the 12 different detected pesticides are classified as endocrine-active substances including the insecticide phosmet and the fungicide fluazinam showing the highest concentrations (0.069 and 0.26 mg kg−1, respectively). Additionally, one disinfectant and one preservation agent was found. Playgrounds in Venosta valley were most often contaminated (76% of all investigated playgrounds), highest concentrations were found in the Low Adige (2.02 mg kg−1). Pesticide concentrations were positively associated with areal proportion of apple orchards in the surroundings, the amount of rainfall and wind speed. In contrast, increasing global irradiance, opposite wind direction, increasing distance to agricultural sites and high wind speeds when pesticide application was not allowed were associated with decreasing pesticide contamination. CONCLUSION: This study is among the first investigating pesticide contamination of public playgrounds together with environmental factors in areas with pesticide-intensive agriculture at the beginning of the growing season. It is likely that playgrounds will be affected by more pesticides and higher concentrations over the course of the crop season. The result, that the majority of the detected pesticides are classified as endocrine active is worrisome as children are especially vulnerable. Hence, we recommend that pesticide risk assessments should better include protection measures for non-target areas

Malaria vaccine candidate: design of a multivalent subunit α-helical coiled coil poly-epitope.

A new strategy for the rapid identification of new malaria antigens based on protein structural motifs was previously described. We identified and evaluated the malaria vaccine potential of fragments of several malaria antigens containing α-helical coiled coil protein motifs. By taking advantage of the relatively short size of these structural fragments, we constructed different poly-epitopes in which 3 or 4 of these segments were joined together via a non-immunogenic linker. Only peptides that are targets of human antibodies with anti-parasite in vitro biological activities were incorporated. One of the constructs, P181, was well recognized by sera and peripheral blood mononuclear cells (PBMC) of adults living in malaria-endemic areas. Affinity purified antigen-specific human antibodies and sera from P181-immunized mice recognised native proteins on malaria-infected erythrocytes in both immunofluorescence and western blot assays. In addition, specific antibodies inhibited parasite development in an antibody dependent cellular inhibition (ADCI) assay. Naturally induced antigen-specific human antibodies were at high titers and associated with clinical protection from malaria in longitudinal follow-up studies in Senegal