scholarly journals Niche Partitioning with Temperature among Heterocystous Cyanobacteria (Scytonema spp., Nostoc spp., and Tolypothrix spp.) from Biological Soil Crusts

2020 ◽  
Vol 8 (3) ◽  
pp. 396 ◽  
Author(s):  
Ana Giraldo-Silva ◽  
Vanessa M. C. Fernandes ◽  
Julie Bethany ◽  
Ferran Garcia-Pichel
Keyword(s):  
Meta Analysis ◽  
Niche Partitioning ◽  
Heat Sensitivity ◽  
Growing Up ◽  
Growth Responses ◽  
Biological Fixation ◽  
Growth Season ◽  
Heterocystous Cyanobacteria ◽  
The Mean

Heterocystous cyanobacteria of biocrusts are key players for biological fixation in drylands, where nitrogen is only second to water as a limiting resource. We studied the niche partitioning among the three most common biocrust heterocystous cyanobacteria sts using enrichment cultivation and the determination of growth responses to temperature in 30 representative isolates. Isolates of Scytonema spp. were most thermotolerant, typically growing up to 40 °C, whereas only those of Tolypothrix spp. grew at 4 °C. Nostoc spp. strains responded well at intermediate temperatures. We could trace the heat sensitivity in Nostoc spp. and Tolypothrix spp. to N2-fixation itself, because the upper temperature for growth increased under nitrogen replete conditions. This may involve an inability to develop heterocysts (specialized N2-fixing cells) at high temperatures. We then used a meta-analysis of biocrust molecular surveys spanning four continents to test the relevance of this apparent niche partitioning in nature. Indeed, the geographic distribution of the three types was clearly constrained by the mean local temperature, particularly during the growth season. This allows us to predict a potential shift in dominance in many locales as a result of global warming, to the benefit of Scytonema spp. populations.

scholarly journals PSVIII-10 Effects of enzyme supplementation in corn distiller’s dried grains with solubles (DDGS) diets on growth performance in broilers: a meta-analysis

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 211-211
Author(s):  
Jae-Cheol Jang ◽  
Zhikai Zeng ◽  
Pedro E Urriola ◽  
Gerald C Shurson
Keyword(s):  
Growth Performance ◽  
Fixed Effects ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Meta Analysis ◽  
Growth Responses ◽  
Exogenous Enzymes ◽  
The Mean ◽  
Enzyme Supplementation ◽  
Mean Differences

Abstract The objective of this study was to conduct a meta-analysis to quantitatively summarize the growth responses of broilers fed cDDGS and the efficacy of various types of dietary enzyme supplementation. A total of 12 publications with 69 observations were included in the database. Individual observations were analyzed using a multivariable linear mixed model. The mean differences (MD) of BWG, FI, and gain efficiency (G/F) were calculated by subtracting either the enzyme response in corn-soybean meal (CSB) or CSB+cDDGS based diets to the control, and was expressed as a percentage (MD = (enzyme – control)/control ×100%). A type of exogenous enzymes (xylanase; protease; carbohydrases; cocktail = proteases + carbohydrases), and feeding phase (starter = d 0 to d 21; finisher = d 21 to d 42 or 49; overall = d 0 to d 42 or more) were included as fixed effects. Dietary enzyme inclusion showed significant improvement on BWG (3.19%, P < 0.01) and G/F (5.69%, P < 0.01) in broilers fed cDDGS diet. However, no significant enzyme responses were observed in broilers fed CSB diet on growth performance. Broilers fed cDDGS diet had increased (P < 0.01) BWG with the addition of protease (3.32 %) and cocktail (3.27 %), whereas addition of xylanased improved (P < 0.01) G/F by (3.56 %) and carbohydrases (1.90 %). Broilers fed cDDGS diet with enzyme supplementation showed greater improvement in BWG (3.71 %, P < 0.01) and G/F (3.78 %, P < 0.01) at finisher phase compared with starter phase. Likewise, Broilers fed CSB diet with enzyme supplementation increased BWG (9.40 %, P < 0.01) and G/F (3.11 %, P < 0.01) at finisher phase. In conclusion, supplementation of xylanase and carbohydrases in cDDGS diet improved G/F, and the enzyme response can be maximized when fed during the finisher phase diet compared with the starter phase diet.

Response Rates in Online Surveys With Affective Disorder Participants

2020 ◽  
Vol 228 (1) ◽  
pp. 14-24 ◽  
Author(s):  
Tanja Burgard ◽  
Michael Bošnjak ◽  
Nadine Wedderhoff
Keyword(s):  
Meta Analysis ◽  
Response Rates ◽  
Contact Mode ◽  
General Anxiety Disorder ◽  
General Anxiety ◽  
Face To Face ◽  
Survey Participation ◽  
The Mean ◽  
Design Characteristics ◽  
E Mail

Abstract. A meta-analysis was performed to determine whether response rates to online psychology surveys have decreased over time and the effect of specific design characteristics (contact mode, burden of participation, and incentives) on response rates. The meta-analysis is restricted to samples of adults with depression or general anxiety disorder. Time and study design effects are tested using mixed-effects meta-regressions as implemented in the metafor package in R. The mean response rate of the 20 studies fulfilling our meta-analytic inclusion criteria is approximately 43%. Response rates are lower in more recently conducted surveys and in surveys employing longer questionnaires. Furthermore, we found that personal invitations, for example, via telephone or face-to-face contacts, yielded higher response rates compared to e-mail invitations. As predicted by sensitivity reinforcement theory, no effect of incentives on survey participation in this specific group (scoring high on neuroticism) could be observed.

The Effect of Desmopressin on Reducing Blood Loss in Cardiac Surgery – A Meta-Analysis of Double-Blind, Placebo-Controlled Trials

1995 ◽  
Vol 74 (04) ◽  
pp. 1064-1070 ◽  
Author(s):  
Marco Cattaneo ◽  
Alan S Harris ◽  
Ulf Strömberg ◽  
Pier Mannuccio Mannucci
Keyword(s):  
Cardiac Surgery ◽  
Blood Loss ◽  
Meta Analysis ◽  
Postoperative Blood Loss ◽  
Controlled Trials ◽  
Double Blind ◽  
Double Blind Placebo ◽  
Transfusion Requirements ◽  
The Mean ◽  
Excessive Blood Loss

SummaryThe effect of desmopressin (DDAVP) on reducing postoperative blood loss after cardiac surgery has been studied in several randomized clinical trials, with conflicting outcomes. Since most trials had insufficient statistical power to detect true differences in blood loss, we performed a meta-analysis of data from relevant studies. Seventeen randomized, double-blind, placebo-controlled trials were analyzed, which included 1171 patients undergoing cardiac surgery for various indications; 579 of them were treated with desmopressin and 592 with placebo. Efficacy parameters were blood loss volumes and transfusion requirements. Desmopressin significantly reduced postoperative blood loss by 9%, but had no statistically significant effect on transfusion requirements. A subanalysis revealed that desmopressin had no protective effects in trials in which the mean blood loss in placebo-treated patients fell in the lower and middle thirds of distribution of blood losses (687-1108 ml/24 h). In contrast, in trials in which the mean blood loss in placebo-treated patients fell in the upper third of distribution (>1109 ml/24 h), desmopressin significantly decreased postoperative blood loss by 34%. Insufficient data were available to perform a sub-analysis on transfusion requirements. Therefore, desmopressin significantly reduces blood loss only in cardiac operations which induce excessive blood loss. Further studies are called to validate the results of this meta-analysis and to identify predictors of excessive blood loss after cardiac surgery.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Determination of Plasminogen in Clots and Thrombi

1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson
Keyword(s):  
Mean Value ◽  
Main Mechanism ◽  
Clot Lysis ◽  
Post Mortem ◽  
Digestion Time ◽  
Normal Volunteers ◽  
Casein Solution ◽  
The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

SERUM TRIIODOTHYRONINE DETERMINATION BY SATURATION ANALYSIS

1973 ◽  
Vol 72 (4) ◽  
pp. 714-726 ◽  
Author(s):  
A. Burger ◽  
B. Miller ◽  
C. Sakoloff ◽  
M. B. Vallotton
Keyword(s):  
Ionic Strength ◽  
Limit Of Detection ◽  
Improved Method ◽  
Accuracy Of Measurement ◽  
Tracer Amount ◽  
The Mean ◽  
Physiological Values ◽  
Hyperthyroid Patients ◽  
Solvent Blank

ABSTRACT An improved method for the determination of serum triiodothyronine (T3) has been developed. After addition of a tracer amount of the hormone, T3 was extracted from 1 ml serum under conditions of pH and ionic strength which favoured T3 extraction (89%) over thyroxine (T4) extraction (58%). Chromatography of the extracted material on Sephadex LH-20 separated T3 completely from residual T4. The T3 eluate was dried, then re-dissolved in 0.5 ml NaOH 0.04 n. To 0.2 ml duplicate aliquots, a standard amount of TBG was added for the competitive protein analysis. After one hour incubation at 4°C, separation of bound from free T3 was achieved on small Sephadex G-25 columns. Overall recovery was 67 ± 10.8% and correction for the loss was made. The solvent blank was 37 ± 27 (sd) ng/100 ml. Accuracy of measurement of known quantities of T3 added to serum was 98.4%. The coefficient of variation within the assay was 6.2% and between the assays it was 11.4%. The limit of detection (0.1 ng) corresponded to a concentration of 25 ng/100 ml. T4 added to serum did not interfere with T3 determination until high non-physiological values were reached. The mean ± sd serum T3 in 54 euthyroid subjects was 153 ± 58 ng/100 ml and in 24 hyperthyroid patients it was 428 ±186 ng/100 ml; 4 out of the 24 hyperthyroid values were within 2 sd of the mean euthyroid group. All the values found in the euthyroid group were well above the limit of detection of the method.

Determination of the Probability Distribution of the Mean Sound Level

2010 ◽  
Vol 35 (4) ◽  
pp. 543-550 ◽  
Author(s):  
Wojciech Batko ◽  
Bartosz Przysucha
Keyword(s):  
Probability Distribution ◽  
Probability Distribution Function ◽  
Mean Value ◽  
Sound Level ◽  
Function Form ◽  
Noise Levels ◽  
Logarithmic Mean ◽  
The Mean ◽  
Estimation Of Uncertainty

AbstractAssessment of several noise indicators are determined by the logarithmic mean <img src="/fulltext-image.asp?format=htmlnonpaginated&src=P42524002G141TV8_html\05_paper.gif" alt=""/>, from the sum of independent random resultsL1;L2; : : : ;Lnof the sound level, being under testing. The estimation of uncertainty of such averaging requires knowledge of probability distribution of the function form of their calculations. The developed solution, leading to the recurrent determination of the probability distribution function for the estimation of the mean value of noise levels and its variance, is shown in this paper.

Simultaneous Determination of Alogliptin, Linagliptin, Saxagliptin, and Sitagliptin in Bulk Drug and Formulation by UPLC Q-TOF-MS

2020 ◽  
Vol 17 (1) ◽  
pp. 95-105
Author(s):  
Ramji Rathod ◽  
Faraat Ali ◽  
Amrish Chandra ◽  
Robin Kumar ◽  
Meenakshi Dahiya ◽  
...  
Keyword(s):  
Internal Standard ◽  
Gradient Elution ◽  
Ultra Performance Liquid Chromatography ◽  
Pharmaceutical Dosage Forms ◽  
Sensitivity And Selectivity ◽  
The Mean ◽  
Bulk Drug ◽  
Positive Ion ◽  
Higher Sensitivity

Background: A simple and sensitive Ultra Performance Liquid Chromatography-Mass Spectrometry method was developed and validated to measure the concentrations of Alogliptin (ALO), Linagliptin (LIN), Saxagliptin (SAX), and Sitagliptin (SIT) using Pioglitazone (PIO) as an internal standard. Methods: Chromatographic separation of six gliptins was achieved on a C-18 column (100×2.1 mm, 2.7 μm) using a mobile phase consisting of formic acid in water, 0.1%v/v: acetonitrile in gradient elution. Electrospray ionization (ESI) source was operated in the positive ion mode. Targeted MS/MS mode on a QTOF MS was used to quantify the drug utilizing the transitions of 340.1(m/z), 473.2 (m/z), 316.2 (m/z), 408.1 (m/z), and 357.1 (m/z) for ALO, LIN, SAX, SIT and PIO respectively. Results: As per ICH Q2R1 guidelines, a detailed validation of the method was carried out and the standard curves were found to be linear over the concentration ranges of 1516.0-4548.1 ng mL-1, 519.8- 1559.4 ng mL-1, 1531.4-4594.3 ng mL-1and 1519.6-4558.8 ng mL-1 for ALO, LIN, SAX and SIT respectively. Precision and accuracy results were within the acceptable limits. The mean recovery was found to be 98.8 _ 0.76 % (GEM), 102.2 _ 1.59 % (LIN), 95.3 _ 2.74 % (SAX) and 99.2 _ 1.75 % (SIT) respectively. Conclusions: The optimized validated UPLC QTOF-MS/MS method offered the advantage of shorter analytical times and higher sensitivity and selectivity. The optimized method is suitable for application in quantitative analysis of pharmaceutical dosage forms for QC laboratory.

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