A STUDY IN THE RELATIVE CONSTANCY OF HIVE BEES AND WILD BEES IN POLLEN GATHERING

1933 ◽  
Vol 9 (4) ◽  
pp. 334-349 ◽  
Author(s):  
W. H. Brittain ◽  
Dorothy E. Newton
Keyword(s):  
Solitary Bees ◽  
Minor Role ◽  
Wild Bees ◽  
Flower Constancy ◽  
Pollen Loads ◽  
Insect Pollinators ◽  
The Difference ◽  
A Minor ◽  
Different Sources ◽  
Significant Superiority

The chief purpose of the investigations described in this paper was to determine the relative pollen constancy of the various insect pollinators of the apple. In addition to the hive bee, these proved to be solitary bees belonging to the genera Halictus and Andrena, with Bremidae and various Diptera playing a minor role. It is pointed out that apparent flower constancy depends a great deal upon availability and that almost any result may be obtained by choosing certain periods in which to make tests. The results, based on analyses of the pollen loads of bees captured in apple blossoms, place the hive bee first as regards the number of pure loads, followed by Halictus, with Andrena a poor third. Taking into consideration the results of the entire season, and the analyses of bees from different sources of pollen, Halictus came first in these particular tests, but the difference is not considered significant. The supposed superiority of the hive bee from the standpoint of constancy does not appear to have been proved. Both Halictus and the hive bee, however, evidenced a significant superiority over the Andrena species studied.

scholarly journals Uptake Study in Lysosome-Enriched Fraction: Critical Involvement of Lysosomal Trapping in Quinacrine Uptake but Not Fluorescence-Labeled Verapamil Transport at Blood-Retinal Barrier

Pharmaceutics ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 747 ◽  
Author(s):  
Yoshiyuki Kubo ◽  
Miki Yamada ◽  
Saki Konakawa ◽  
Shin-ichi Akanuma ◽  
Ken-ichi Hosoya
Keyword(s):  
Retinal Pigment ◽  
Transport Processes ◽  
Minor Role ◽  
Bafilomycin A1 ◽  
Blood Retinal Barrier ◽  
Retinal Capillary ◽  
Intracellular Compartments ◽  
The Difference ◽  
A Minor

Lysosomal trapping at the blood–retinal barrier (BRB) was investigated through quinacrine and fluorescence-labeled verapamil (EFV) uptake. Quinacrine uptake by conditionally immortalized rat retinal capillary endothelial (TR-iBRB2) cells suggested saturable and non-saturable transport processes in the inner BRB. The reduction of quinacrine uptake by bafilomycin A1 suggested quinacrine distribution to the acidic intracellular compartments of the inner BRB, and this notion was also supported in confocal microscopy. In the study using the lysosome-enriched fraction of TR-iBRB2 cells, quinacrine uptake was inhibited by bafilomycin A1, suggesting the lysosomal trapping of quinacrine in the inner BRB. Pyrilamine, clonidine, and nicotine had no effect on quinacrine uptake, suggesting the minor role of lysosomal trapping in their transport across the inner BRB. Bafilomycin A1 had no effect on EFV uptake, and lysosomal trapping driven by the acidic interior pH was suggested as a minor mechanism for EFV transport in the inner BRB. The minor contribution of lysosomal trapping was supported by the difference in inhibitory profiles between EFV and quinacrine uptakes. Similar findings were observed in the outer BRB study with the fraction of conditionally immortalized rat retinal pigment epithelial (RPE-J) cells. These results suggest the usefulness of lysosome-enriched fractions in studying lysosomal trapping at the BRB.

The German Labour Market Miracle

2010 ◽  
Vol 214 ◽  
pp. R38-R50 ◽  
Author(s):  
Jens Boysen-Hogrefe ◽  
Dominik Groll
Keyword(s):  
Labour Market ◽  
Minor Role ◽  
Dynamic Simulations ◽  
The Great Recession ◽  
Wage Moderation ◽  
Time Work ◽  
The Difference ◽  
A Minor ◽  
Short Time ◽  
Minor Reaction

This paper lays out the various reasons for the exceptional performance of the German labour market during and after the Great Recession of 2008/9. The reference point of our analysis is provided by an empirical model of both total hours worked and employment. We conduct dynamic simulations of the crisis period to assess how surprising the reaction of the labour market really was. We argue that the most important precondition for the minor reaction of employment during this crisis was the pronounced wage moderation observed in the years before, which constitutes a distinct difference to all other recessions in Germany. Beyond that, the flexibility of adjusting working time, which has increased considerably during the past ten years, facilitated a tendency to labour hoarding. In contrast, short-time work plays a minor role in explaining the difference from previous recessions, since this instrument has always been available to firms in Germany and its use has not been extraordinary compared with earlier recessions.

The Weights of Individual Grains of the Wheat Ear in Relation to Their Growth Potential, the Supply of Assimilate and Interaction Between Grains

1978 ◽  
Vol 5 (1) ◽  
pp. 61 ◽  
Author(s):  
PM Bremner ◽  
HM Rawson
Keyword(s):  
Vascular System ◽  
Growth Potential ◽  
Assimilate Transport ◽  
Major Influence ◽  
Minor Role ◽  
Intrinsic Capacity ◽  
The Difference ◽  
The One ◽  
Individual Grains ◽  
A Minor

The work reported here was done to explore the extent to which the mature weight of a grain is determined by (i) its potential for growth, defined as its intrinsic capacity to accumulate dry matter, and (ii) the resistance to assimilate transport imposed by the vascular system of the ear. Estimation of growth potential was attempted by observing the effects of systematic patterns of grain removal on the mature weights of grains remaining, these being compared with weights of matched grains from intact ears. Resistance to transport of assimilate was inferred from the apparent order of priority between grains for the supply of assimilate, as revealed by comparing their weights when assimilate supply was either normal, or reduced by plant shading. When neighbouring grains were removed, those remaining usually grew larger to an extent that indicated growth potential appreciably in excess of that utilized in intact ears under the most favourable conditions. Although grains within a spikelet of an intact ear attain quite different weights, the experiments suggested that their differing potentials for growth seemed to play only a minor role in this, and that the major influence was the relative ease with which assimilate could reach the grains; this depended largely on the distance of the grains from the spike rachis. Comparing between spikelets, the difference found in intact ears between grains in the same spikelet location tended to persist when some grains were removed from each spikelet, indicating a possible role of growth potential as a controlling influence. This may be partly due to the sequence of morphogenesis, established as early as the double ridge stage. Although the removal of competing grains within a spikelet usually enhanced the growth of the one remaining, this was not always so; there was evidence from one experiment that removal of competing grains towards the spikelet apex represented the removal of some beneficial influence. The bearing of the results on possible limitations to grain yield are discussed.

The use of ziprasidone in clinical practice: Analysis of pharmacokinetic and pharmacodynamic aspects from data of a drug monitoring survey

2009 ◽  
Vol 24 (3) ◽  
pp. 143-148 ◽  
Author(s):  
Friederike Vogel ◽  
Reinhard Gansmüller ◽  
Thomas Leiblein ◽  
Otto Dietmaier ◽  
Hans Wassmuth ◽  
...  
Keyword(s):  
Drug Monitoring ◽  
Serum Levels ◽  
Total Sample ◽  
Therapeutic Drug ◽  
Minor Role ◽  
Clinical Effects ◽  
Serum Concentrations ◽  
Treatment Optimization ◽  
The Difference ◽  
A Minor

AbstractThis study related clinical effects to daily doses and serum concentrations of ziprasidone by retrospective analysis of data from a therapeutic drug monitoring (TDM) survey established for patients treated with the new antipsychotic drug. In the total sample of 463 patients ziprasidone doses ranged between 20 and 320 mg/d and correlated significantly (r2 = 0.093, P < 0.01) with serum concentrations. The latter were highly variable within and between individual patients (between patients median 67 ng/ml, 25–75th percentile 40–103 ng/ml). Pharmacokinetic interactions with comedication played a minor role. According to the clinical global impressions (CGI) scale most of the 348 patients who were under antipsychotic monotherapy with ziprasidone were either much or very much improved (43.3 and 17.3%, respectively). The previously proposed therapeutic range of 50–130 ng/ml ziprasidone in serum or plasma, which can in effect be used interchangeable, was confirmed. In patients who were at least much improved and defined as “responders” mean serum concentrations of ziprasidone were 80 ng/ml and 78 ng/ml in patients who did not reach this improvement score. In patients with serum levels above or below 50 ng/ml, the number of responders was 66 or 63%, respectively. The difference between the two groups was not significant (P = 0.375), and improvement or side effects did not correlate significantly (P > 0.05) with doses or serum levels. It is concluded that TDM of ziprasidone may be useful for treatment optimization because of highly variable serum concentrations resulting under therapeutically recommended doses of the drug.

scholarly journals Effects of mixing on resolved and unresolved scales on stratospheric age of air

2017 ◽  
Vol 17 (12) ◽  
pp. 7703-7719 ◽  
Author(s):  
Simone Dietmüller ◽  
Hella Garny ◽  
Felix Plöger ◽  
Patrick Jöckel ◽  
Duy Cai
Keyword(s):  
Atmospheric Chemistry ◽  
Climate Model ◽  
Lagrangian Model ◽  
Mixing Efficiency ◽  
Minor Role ◽  
Positive Trend ◽  
Residual Circulation ◽  
Advection Schemes ◽  
The Difference ◽  
A Minor

Abstract. Mean age of air (AoA) is a widely used metric to describe the transport along the Brewer–Dobson circulation. We seek to untangle the effects of different processes on the simulation of AoA, using the chemistry–climate model EMAC (ECHAM/MESSy Atmospheric Chemistry) and the Chemical Lagrangian Model of the Stratosphere (CLaMS). Here, the effects of residual transport and two-way mixing on AoA are calculated. To do so, we calculate the residual circulation transit time (RCTT). The difference of AoA and RCTT is defined as aging by mixing. However, as diffusion is also included in this difference, we further use a method to directly calculate aging by mixing on resolved scales. Comparing these two methods of calculating aging by mixing allows for separating the effect of unresolved aging by mixing (which we term aging by diffusion in the following) in EMAC and CLaMS. We find that diffusion impacts AoA by making air older, but its contribution plays a minor role (order of 10 %) in all simulations. However, due to the different advection schemes of the two models, aging by diffusion has a larger effect on AoA and mixing efficiency in EMAC, compared to CLaMS. Regarding the trends in AoA, in CLaMS the AoA trend is negative throughout the stratosphere except in the Northern Hemisphere middle stratosphere, consistent with observations. This slight positive trend is neither reproduced in a free-running nor in a nudged simulation with EMAC – in both simulations the AoA trend is negative throughout the stratosphere. Trends in AoA are mainly driven by the contributions of RCTT and aging by mixing, whereas the contribution of aging by diffusion plays a minor role.

scholarly journals Effects of mixing on resolved and unresolved scales on stratospheric age of air

2017 ◽  
Author(s):  
Simone Dietmüller ◽  
Hella Garny ◽  
Felix Plöger ◽  
Patrick Jöckel ◽  
Cai Duy
Keyword(s):  
Climate Model ◽  
Transport Model ◽  
Mixing Efficiency ◽  
Minor Role ◽  
Positive Trend ◽  
Residual Circulation ◽  
Advection Schemes ◽  
Residual Transport ◽  
The Difference ◽  
A Minor

Abstract. Mean age of air (AoA) is a widely used metric to describe the transport along the Brewer-Dobson circulation. We seek to untangle the effects of different processes on the simulation of AoA, using the chemistry-climate model EMAC and the Lagrangian chemistry transport model CLaMS. Here, the effects of residual transport and two-way mixing on AoA are calculated. To do so, we calculate the residual circulation transit time (RCTT). The difference of AoA and RCTT is defined as aging by mixing. However, as diffusion is also included in this difference, we further use a method to directly calculate aging by mixing on resolved scales. Comparing these two methods of calculating aging by mixing allows for separating the effect of unresolved aging by mixing (which we term "aging by diffusion" in the following) in EMAC and CLaMS. We find that diffusion impacts AoA by making air older, but its contribution plays a minor role (order of 10 %) in all simulations. However, due to the different advection schemes of the two models, aging by diffusion has a larger effect on AoA and mixing efficiency in EMAC, compared to CLaMS. Regarding the trends in AoA, in CLaMS the AoA trend is negative throughout the stratosphere except in the northern hemisphere middle stratosphere, consistent with observations. This slight positive trend is neither reproduced in a free-running nor in a nudged simulation with EMAC – in both simulations the AoA trend is negative throughout the stratosphere. Trends in AoA are mainly driven by the contributions of RCTT and aging by mixing, whereas the contribution of aging by diffusion plays a minor role.

scholarly journals Investigation of the effective peak supersaturation for liquid-phase clouds at the high-alpine site Jungfraujoch, Switzerland (3580 m a.s.l.)

2014 ◽  
Vol 14 (2) ◽  
pp. 1123-1139 ◽  
Author(s):  
E. Hammer ◽  
N. Bukowiecki ◽  
M. Gysel ◽  
Z. Jurányi ◽  
C. R. Hoyle ◽  
...  
Keyword(s):  
Climate Models ◽  
Cloud Condensation Nuclei ◽  
Radiation Budget ◽  
Minor Role ◽  
Research Station ◽  
Cumulus Clouds ◽  
Air Masses ◽  
The Difference ◽  
Aerosol Cloud Interactions ◽  
A Minor

Abstract. Aerosols influence the Earth's radiation budget directly through absorption and scattering of solar radiation in the atmosphere but also indirectly by modifying the properties of clouds. However, climate models still suffer from large uncertainties as a result of insufficient understanding of aerosol-cloud interactions. At the high altitude research station Jungfraujoch (JFJ; 3580 m a.s.l., Switzerland) cloud condensation nuclei (CCN) number concentrations at eight different supersaturations (SS) from 0.24% to 1.18% were measured using a CCN counter during Summer 2011. Simultaneously, in-situ aerosol activation properties of the prevailing ambient clouds were investigated by measuring the total and interstitial (non-activated) dry particle number size distributions behind two different inlet systems. Combining all experimental data, a new method was developed to retrieve the so-called effective peak supersaturation SSpeak, as a measure of the SS at which ambient clouds are formed. A 17-month CCN climatology was then used to retrieve the SSpeak values also for four earlier summer campaigns (2000, 2002, 2004 and 2010) where no direct CCN data were available. The SSpeak values varied between 0.01% and 2.0% during all campaigns. An overall median SSpeak of 0.35% and dry activation diameter of 87 nm was observed. It was found that the difference in topography between northwest and southeast plays an important role for the effective peak supersaturation in clouds formed in the vicinity of the JFJ, while differences in the number concentration of potential CCN only play a minor role. Results show that air masses coming from the southeast (with the slowly rising terrain of the Aletsch Glacier) generally experience lower SSpeak values than air masses coming from the northwest (steep slope). The observed overall median values were 0.41% and 0.22% for northwest and southeast wind conditions, respectively, corresponding to literature values for cumulus clouds and shallow-layer clouds. These cloud types are consistent with weather observations routinely performed at the JFJ.

scholarly journals Disentangling the causes for faster-X evolution in aphids

2017 ◽  
Author(s):  
J Jaquiéry ◽  
J Peccoud ◽  
T Ouisse ◽  
F Legeai ◽  
N Prunier-Leterme ◽  
...  
Keyword(s):  
Large Fraction ◽  
Expression Patterns ◽  
Minor Role ◽  
Effective Population ◽  
Entire Genome ◽  
Substitution Rates ◽  
X Chromosomes ◽  
The Difference ◽  
Efficiency Of Selection ◽  
A Minor

AbstractFaster evolution of X chromosomes has been documented in several species and results from the increased efficiency of selection on recessive alleles in hemizygous males and/or from increased drift due to the smaller effective population size of X chromosomes. Aphids are excellent models for evaluating the importance of selection in faster-X evolution, because their peculiar life-cycle and unusual inheritance of sex-chromosomes lead to equal effective population sizes for X and autosomes. Because we lack a high-density genetic map for the pea aphid whose complete genome has been sequenced, we assigned its entire genome to the X and autosomes based on ratios of sequencing depth in males and females. Unexpectedly, we found frequent scaffold misassembly, but we could unambiguously locate 13,726 genes on the X and 19,263 on autosomes. We found higher non-synonymous to synonymous substitutions ratios (dN/dS) for X-linked than for autosomal genes. Our analyses of substitution rates together with polymorphism and expression data showed that relaxed selection is likely to contribute predominantly to faster-X as a large fraction of X-linked genes are expressed at low rates and thus escape selection. Yet, a minor role for positive selection is also suggested by the difference between substitution rates for X and autosomes for male-biased genes (but not for asexual female-biased genes) and by lower Tajima’s D for X-linked than for autosomal genes with highly male-biased expression patterns. This study highlights the relevance of organisms displaying alternative inheritance of chromosomes to the understanding of forces shaping genome evolution.

scholarly journals Investigation of the effective peak supersaturation for liquid-phase clouds at the high-alpine site Jungfraujoch, Switzerland (3580 m a.s.l.)

2013 ◽  
Vol 13 (8) ◽  
pp. 20419-20462 ◽  
Author(s):  
E. Hammer ◽  
N. Bukowiecki ◽  
M. Gysel ◽  
Z. Jurányi ◽  
C. R. Hoyle ◽  
...  
Keyword(s):  
Climate Models ◽  
Cloud Condensation Nuclei ◽  
Radiation Budget ◽  
Minor Role ◽  
Research Station ◽  
Cumulus Clouds ◽  
Air Masses ◽  
The Difference ◽  
Aerosol Cloud Interactions ◽  
A Minor

Abstract. Aerosols influence the Earth's radiation budget directly through absorption and scattering of solar radiation in the atmosphere but also indirectly by modifying the properties of clouds. However, climate models still suffer from large uncertainties as a result of insufficient understanding of aerosol-cloud interactions. At the high altitude research station Jungfraujoch (JFJ; 3580 m a.s.l., Switzerland) cloud condensation nuclei (CCN) number concentrations at eight different supersaturations (SS) from 0.24% to 1.18% were measured using a CCN counter during Summer 2011. Simultaneously, in-situ aerosol activation properties of the prevailing ambient clouds were investigated by measuring the total and interstitial (non-activated) dry particle number size distributions behind two different inlet systems. Combining all experimental data, a new method was developed to retrieve the so-called effective peak supersaturation SSpeak, as a measure of the SS at which ambient clouds are formed. A 17 month CCN climatology was then used to retrieve the SSpeak values also for four earlier summer campaigns (2000, 2002, 2004 and 2010) where no direct CCN data were available. The SSpeak values varied between 0.01% and 2.0% during all campaigns. An overall median SSpeak of 0.35% and dry activation diameter of 87 nm was observed. It was found that the difference in topography between northwest and southeast plays an important role for the effective peak supersaturation in clouds formed in the vicinity of the JFJ, while differences in the number concentration of potential CCN only play a minor role. Results show that air masses coming from the southeast (with the slowly rising terrain of the Aletsch Glacier) generally experience lower SSpeak values than air masses coming from the northwest (steep slope). The observed overall median values were 0.41% and 0.22% for northwest and southeast wind conditions, respectively, corresponding to literature values for cumulus clouds and shallow-layer clouds. These cloud types are consistent with weather observations routinely performed at the JFJ.

scholarly journals Tumor-reactivity of d2 negative gdT cells and the role of the gdT cell receptor

2021 ◽  
Author(s):  
Suzanne van Dooremalen ◽  
Anke Janssen ◽  
Lauri Bloemenkamp ◽  
Austin Yonka ◽  
Dennis Beringer ◽  
...  
Keyword(s):  
Potential Role ◽  
Cell Receptor ◽  
Great Promise ◽  
Minor Role ◽  
Tumor Cell Lines ◽  
Cmv Infection ◽  
Tumor Recognition ◽  
A Minor ◽  
Different Sources

abT cells engineered to express a defined gdTCR (TEG) to attack cancer cells have shown great promise when using a g9d2TCR to redirect abT cells. Reports by us and recent reports by others support the key role of the g9d2TCR in cancer recognition. We further emphasized the crucial role of the dTCR chain and that differences in CDR3 sequences of the dTCR chain modulates functional avidity of TEGs. We and others demonstrated that also d2 negative gdTCRs are able to redirect abT cells towards different tumor cell lines. However, some studies suggest that d2 negative gdTCRs play a minor role in the tumor recognition by d2 negative gdT cells. In addition for both modes of action for tumor-recognition, d2 negative gdTCR-dependent and -independent, it has been suggested that CMV infection is not only a major driver of d2 negative gdT cell expansion but also induces tumor-cross reactive d2 negative gdT cells. Therefore, we aimed to systematically explore frequencies of tumor reactive d2 negative gdT cells in naive repertoires (cord blood) and patients with or without CMV infection and examined the potential role the parental d2 negative gdTCR in anti-tumor reactivity of selected clones. We observed that approximately 30% of all tested clones were tumor-reactive, though no differences were observed between different sources. Surprisingly, none of the so far tested gdTCR did mediate strong anti-tumor reactivity of the parental clones. Though numbers of tested TCR sequences are still low, our data imply that tumor-reactivity of d2 negative gdT cells is frequently not mediated by the d2 negative gdTCR alone.

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