Adult nutrition and butterfly fitness: effects of diet quality on reproductive output, egg composition, and egg hatching success

<p>Abstract</p> <p>Background</p> <p>In the Lepidoptera it was historically believed that adult butterflies rely primarily on larval-derived nutrients for reproduction and somatic maintenance. However, recent studies highlight the complex interactions between storage reserves and adult income, and that the latter may contribute significantly to reproduction. Effects of adult diet were commonly assessed by determining the number and/or size of the eggs produced, whilst its consequences for egg composition and offspring viability were largely neglected (as is generally true for insects). We here specifically focus on these latter issues by using the fruit-feeding tropical butterfly <it>Bicyclus anynana</it>, which is highly dependent on adult-derived carbohydrates for reproduction.</p> <p>Results</p> <p>Adult diet of female <it>B. anynana </it>had pronounced effects on fecundity, egg composition and egg hatching success, with butterflies feeding on the complex nutrition of banana fruit performing best. Adding vitamins and minerals to a sucrose-based diet increased fecundity, but not offspring viability. All other groups (plain sucrose solution, sucrose solution enriched with lipids or yeast) had a substantially lower fecundity and egg hatching success compared to the banana group. Differences were particularly pronounced later in life, presumably indicating the depletion of essential nutrients in sucrose-fed females. Effects of adult diet on egg composition were not straightforward, indicating complex interactions among specific compounds. There was some evidence that total egg energy and water content were related to hatching success, while egg protein, lipid, glycogen and free carbohydrate content did not seem to limit successful development.</p> <p>Conclusion</p> <p>The patterns shown here exemplify the complexity of reproductive resource allocation in <it>B. anynana</it>, and the need to consider egg composition and offspring viability when trying to estimate the effects of adult nutrition on fitness in this butterfly and other insects.</p

Story Possibilities in Religious Studies at USD

The etiology of overweight and obesity is a mixture of genetic determinants, environmental factors, and health behaviors. Especially intra- and interpersonal inactive behaviors, here termed convenience, seems to play an important role. The objective was to develop and validate the Convenience Behavior Questionnaire (CBQ) to assess convenience-related items and their association with overweight and obesity in a large population. A sample of 1233 subjects aged 18–82 years from six population groups took part in a self-administered questionnaire. Test-retest reliability was estimated and the independent association between convenience-related items and overweight and obesity was investigated. Principal component analysis revealed three factors (avoidance behaviors, social interaction behaviors and domestic environmental factors) which explained 43.4% of the variance contributing to the CBQ. Cronbach's α ranged from 0.80–0.89. Test-retest reliability using intra-class correlation was acceptable ≥ 0.70. Forward stepwise logistic regression analysis, including gender, education level, age and TV viewing on weekends showed a positive relation of convenience behavior and overweight (OR: 1.40; 95% CI: 1.01–1.96; P = 0.048), while physical activity status was not significantly associated with overweight (OR: 1.09; 95% CI: 0.77–1.54; P = 0.629). The CBQ seems to be a reliable tool which considers non-traditional behaviors related to overweight development. Interestingly our findings revealed a better relationship between convenience-related behavior with overweight and obesity than the habitual physical activity score

Microcirculatory alterations in ischemia–reperfusion injury and sepsis: effects of activated protein C and thrombin inhibition

Experimental studies in ischemia–reperfusion and sepsis indicate that activated protein C (APC) has direct anti-inflammatory effects at a cellular level. In vivo, however, the mechanisms of action have not been characterized thus far. Intravital multifluorescence microscopy represents an elegant way of studying the effect of APC on endotoxin-induced leukocyte–endothelial-cell interaction and nutritive capillary perfusion failure. These studies have clarified that APC effectively reduces leukocyte rolling and leukocyte firm adhesion in systemic endotoxemia. Protection from leukocytic inflammation is probably mediated by a modulation of adhesion molecule expression on the surface of leukocytes and endothelial cells. Of interest, the action of APC and antithrombin in endotoxin-induced leukocyte–endothelial-cell interaction differs in that APC inhibits both rolling and subsequent firm adhesion, whereas antithrombin exclusively reduces the firm adhesion step. The biological significance of this differential regulation of inflammation remains unclear, since both proteins are capable of reducing sepsis-induced capillary perfusion failure. To elucidate whether the action of APC and antithrombin is mediated by inhibition of thrombin, the specific thrombin inhibitor hirudin has been examined in a sepsis microcirculation model. Strikingly, hirudin was not capable of protecting from sepsis-induced microcirculatory dysfunction, but induced a further increase of leukocyte–endothelial-cell interactions and aggravated capillary perfusion failure when compared with nontreated controls. Thus, the action of APC on the microcirculatory level in systemic endotoxemia is unlikely to be caused by a thrombin inhibition-associated anticoagulatory action

Experimentally verified pulse formation model for high-power femtosecond VECSELs

Optically pumped vertical-external-cavity surface-emitting lasers (OP-VECSELs), passively modelocked with a semiconductor saturable absorber mirror (SESAM), have generated the highest average output power from any sub-picosecond semiconductor laser. Many applications, including frequency comb synthesis and coherent supercontinuum generation, require pulses in the sub-300-fs regime. A quantitative understanding of the pulse formation mechanism is required in order to reach this regime while maintaining stable, high-average-power performance. We present a numerical model with which we have obtained excellent quantitative agreement with two recent experiments in the femtosecond regime, and we have been able to correctly predict both the observed pulse duration and the output power for the first time. Our numerical model not only confirms the soliton-like pulse formation in the femtosecond regime, but also allows us to develop several clear guidelines to scale the performance toward shorter pulses and higher average output power. In particular, we show that a key VECSEL design parameter is a high gain saturation fluence. By optimizing this parameter, 200-fs pulses with an average output power of more than 1 W should be possible

Possible limitations of dolphin echolocation: a simulation study based on a cross-modal matching experiment

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wei, C., Hoffmann-Kuhnt, M., Au, W. W. L., Ho, A. Z. H., Matrai, E., Feng, W., Ketten, D. R., & Zhang, Y. Possible limitations of dolphin echolocation: a simulation study based on a cross-modal matching experiment. Scientific Reports, 11(1), (2021): 6689, https://doi.org/10.1038/s41598-021-85063-2.Dolphins use their biosonar to discriminate objects with different features through the returning echoes. Cross-modal matching experiments were conducted with a resident bottlenose dolphin (Tursiops aduncus). Four types of objects composed of different materials (water-filled PVC pipes, air-filled PVC pipes, foam ball arrays, and PVC pipes wrapped in closed-cell foam) were used in the experiments, respectively. The size and position of the objects remained the same in each case. The data collected in the experiment showed that the dolphin’s matching accuracy was significantly different across the cases. To gain insight into the underlying mechanism in the experiments, we used finite element methods to construct two-dimensional target detection models of an echolocating dolphin in the vertical plane, based on computed tomography scan data. The acoustic processes of the click’s interaction with the objects and the surrounding media in the four cases were simulated and compared. The simulation results provide some possible explanations for why the dolphin performed differently when discriminating the objects that only differed in material composition in the previous matching experiments.One of the authors, Wei. C is supported by a Forrest Research Foundation Fellowship. Support for D. Ketten for this effort was provided by the Joint Industry Programme and by the Helmholtz Foundation. This work was also supported by the Hawaii Institute of Marine Biology (HIMB) contribution No. 1630 and School of Ocean and Earth Science and Technology (SOEST) contribution No. 9452

Local Isoelectronic Reactivity of Solid Surfaces

The quantity w^N(r) = ( 1/ k^2 T_el)[partial n(r, T_el) / partial T_el]_(v(r),N) is introduced as a convenient measure of the local isoelectronic reactivity of surfaces. It characterizes the local polarizability of the surface and it can be calculated easily. The quantity w^N(r) supplements the charge transfer reactivity measured e.g. by the local softness to which it is closely related. We demonstrate the applicability and virtues of the function w^N(r) for the example of hydrogen dissociation and adsorption on Pd(100).Comment: RevTeX, 13 pages, 3 figures, to appear in Phys. Rev. Let

Towards an understanding of hole superconductivity

From the very beginning K. Alex M\"uller emphasized that the materials he and George Bednorz discovered in 1986 were $hole$ superconductors. Here I would like to share with him and others what I believe to be $the$ key reason for why high $T_c$ cuprates as well as all other superconductors are hole superconductors, which I only came to understand a few months ago. This paper is dedicated to Alex M\"uller on the occasion of his 90th birthday.Comment: Dedicated to Alex M\"uller on the Occasion of his 90th Birthday. arXiv admin note: text overlap with arXiv:1703.0977

Electric Field Control of Spin Transport

Spintronics is an approach to electronics in which the spin of the electrons is exploited to control the electric resistance R of devices. One basic building block is the spin-valve, which is formed if two ferromagnetic electrodes are separated by a thin tunneling barrier. In such devices, R depends on the orientation of the magnetisation of the electrodes. It is usually larger in the antiparallel than in the parallel configuration. The relative difference of R, the so-called magneto-resistance (MR), is then positive. Common devices, such as the giant magneto-resistance sensor used in reading heads of hard disks, are based on this phenomenon. The MR may become anomalous (negative), if the transmission probability of electrons through the device is spin or energy dependent. This offers a route to the realisation of gate-tunable MR devices, because transmission probabilities can readily be tuned in many devices with an electrical gate signal. Such devices have, however, been elusive so far. We report here on a pronounced gate-field controlled MR in devices made from carbon nanotubes with ferromagnetic contacts. Both the amplitude and the sign of the MR are tunable with the gate voltage in a predictable manner. We emphasise that this spin-field effect is not restricted to carbon nanotubes but constitutes a generic effect which can in principle be exploited in all resonant tunneling devices.Comment: 22 pages, 5 figure