Locomotion in Response to Shifting Climate Zones: Not So Fast

Although a species’ locomotor capacity is suggestive of its ability to escape global climate change, such a suggestion is not necessarily straightforward. Species vary substantially in locomotor capacity, both ontogenetically and within/among populations, and much of this variation has a genetic basis. Accordingly, locomotor capacity can and does evolve rapidly, as selection experiments demonstrate. Importantly, even though this evolution of locomotor capacity may be rapid enough to escape changing climate, genetic correlations among traits (often due to pleiotropy) are such that successful or rapid dispersers are often limited in colonization or reproductive ability, which may be viewed as a trade-off. The nuanced assessment of this variation and evolution is reviewed for well-studied models: salmon, flying versus flightless insects, rodents undergoing experimental evolution, and metapopulations of butterflies. This work reveals how integration of physiology with population biology and functional genomics can be especially informative

Locomotion in Response to Shifting Climate Zones: Not So Fast

Although a species’ locomotor capacity is suggestive of its ability to escape global climate change, such a suggestion is not necessarily straightforward. Species vary substantially in locomotor capacity, both ontogenetically and within/among populations, and much of this variation has a genetic basis. Accordingly, locomotor capacity can and does evolve rapidly, as selection experiments demonstrate. Importantly, even though this evolution of locomotor capacity may be rapid enough to escape changing climate, genetic correlations among traits (often due to pleiotropy) are such that successful or rapid dispersers are often limited in colonization or reproductive ability, which may be viewed as a trade-off. The nuanced assessment of this variation and evolution is reviewed for well-studied models: salmon, flying versus flightless insects, rodents undergoing experimental evolution, and metapopulations of butterflies. This work reveals how integration of physiology with population biology and functional genomics can be especially informative

Densovirus induces winged morphs in asexual clones of the rosy apple aphid, Dysaphis plantaginea

Winged morphs of aphids are essential for their dispersal and survival. We discovered that the production of the winged morph in asexual clones of the rosy apple aphid, Dysaphis plantaginea, is dependent on their infection with a DNA virus, Dysaphis plantaginea densovirus (DplDNV). Virus-free clones of the rosy apple aphid, or clones infected singly with an RNA virus, rosy apple aphid virus (RAAV), did not produce the winged morph in response to crowding and poor plant quality. DplDNV infection results in a significant reduction in aphid reproduction rate, but such aphids can produce the winged morph, even at low insect density, which can fly and colonize neighboring plants. Aphids infected with DplDNV produce a proportion of virus-free aphids, which enables production of virus-free clonal lines after colonization of a new plant. Our data suggest that a mutualistic relationship exists between the rosy apple aphid and its viruses. Despite the negative impact of DplDNV on rosy apple aphid reproduction, this virus contributes to their survival by inducing wing development and promoting dispersal

Experimental evaluation of a solid oxide fuel cell system exposed to inclinations and accelerations by ship motions

Solid Oxide Fuel Cell (SOFC) systems have the potential to reduce emissions from seagoing vessels. However, it is unknown whether ship motions influence the system's operation. In this research, a 1.5 kW SOFC module is operated on an inclination platform that emulates ship motions, to evaluate the influence of static and dynamic inclinations on the system's safety, operation, and lifetime. The test campaign consists of a static inclination test, a dynamic test, a degradation test, and a high acceleration test. There were no interruptions in the power supply during the different tests, and no detectable gas leakages or safety hazards. Although the SOFC does not fail in any test condition, dynamic inclinations result in forced oscillations in the fuel regulation, which propagate through the system by different feedback loops in the control architecture, leading to significant deviations in the operational parameters of the system. Additionally, for motion periods from 16 to 26 s, reoccurring exceedance of the fuel utilisation results in a gradual reduction of the power supply. Several enhancements are recommended to improve the design of SOFCs and marine fuel cell regulations to ensure their safe operation on ships.</p

RELIABILITY AND ACCURACY OF A STANDARDIZED SHALLOW WATER RUNNING TEST TO DETERMINE CARDIORESPIRATORY FITNESS

A standardized fitness assessment is critical for the development of an individualized exercise prescription. Although the benefits of aquatic exercise have been well established, there remains the need for a standardized nonswimming protocol to accurately assess cardiorespiratory fitness (CRF) in shallow water. The present investigation was designed to assess (a) the reliability of a standardized shallow water run (SWR) test of CRF and (b) the accuracy of a standardized SWR compared with a land-based treadmill (LTM)test. Twenty-three healthy women (20 6 3 years), with body mass index (23.5 6 3 kg$m22), performed 2 shallow water peak oxygen consumption (V_ O2peak) running tests (SWRa and SWRb), and 1 V_ O2max LTM. Intraclass correlation coefficients indicated moderately strong reliability for V_ O2peak (ml$kg21$min21) (r = 0.73, p , 0.01), HR peak (b$min21) (r = 0.82; p , 0.01), and O2pulse (V_ O2 [ml$kg21$min21]$HR [b$min21]) (r = 0.77, p , 0.01). Using paired t-tests and Pearson’s correlations, SWR V_ O2peak and HR peak were significantly lower than during LTM (p # 0.05) and showed moderate correlations of 0.60 and 0.58 (p , 0.001) to LTM. O2pulse was similar (p . 0.05) for the SWR and LTM tests with a moderate correlation of 0.63. A standardized SWR test asa measure of CRF is a reliable, and to some degree, valid alternative to conventional protocols and may be used by strength and conditioning professionals to measure program outcomes and monitor training progress. Furthermore, this protocol provides a water-based option for CRF assessment among healthy women and offers insight toward the development of an effective protocol that can accommodate individuals with limited mobility, or those seeking less musculoskeletal impact from traditional land-based types of training

\u3ci\u3eJhe in Gryllus assimilis\u3c/i\u3e: Cloning, sequence-activity associations and phylogeny

The 458 amino acid sequence of a mature JHE protein from the cricket Gryllus assimilis was identified after isolating the partial cDNA sequence encoding this protein from a fat body and midgut cDNA library. This hemimetabolan JHE sequence shows over 40% amino acid similarity to the known JHE sequences of several holometabolous insects. It also includes previously determined peptide sequences for G. assimilis JHE as well as two other motifs associated with JHE enzymes in holometabolous insects. The predicted molecular weight of the protein agrees with that of the JHE previously purified from G. assimilis. Partial genomic sequence encoding the Jhe contains two large (1330 and 2918 bp) introns. No coding DNA sequence variation was observed over a 1293 bp region between selected lines differing six to eight-fold in hemolymph JHE activity. However, a 19 bp indel was found in one of the introns; the insertion was strongly associated with elevated hemolymph activity, both in the selected lines and in the F2 progeny of crosses between them. Phylogenetic analyses localised the G. assimilis JHE to a clade containing dipteran and coleopteran JHEs, with lepidopteran JHEs occurring in a separate clade

\u3ci\u3eJhe in Gryllus assimilis\u3c/i\u3e: Cloning, sequence-activity associations and phylogeny

The 458 amino acid sequence of a mature JHE protein from the cricket Gryllus assimilis was identified after isolating the partial cDNA sequence encoding this protein from a fat body and midgut cDNA library. This hemimetabolan JHE sequence shows over 40% amino acid similarity to the known JHE sequences of several holometabolous insects. It also includes previously determined peptide sequences for G. assimilis JHE as well as two other motifs associated with JHE enzymes in holometabolous insects. The predicted molecular weight of the protein agrees with that of the JHE previously purified from G. assimilis. Partial genomic sequence encoding the Jhe contains two large (1330 and 2918 bp) introns. No coding DNA sequence variation was observed over a 1293 bp region between selected lines differing six to eight-fold in hemolymph JHE activity. However, a 19 bp indel was found in one of the introns; the insertion was strongly associated with elevated hemolymph activity, both in the selected lines and in the F2 progeny of crosses between them. Phylogenetic analyses localised the G. assimilis JHE to a clade containing dipteran and coleopteran JHEs, with lepidopteran JHEs occurring in a separate clade

Reliability and Validity of a Flume-Based Maximal Oxygen Uptake Swimming Test

A mode-specific swimming protocol to assess maximal aerobic uptake (VO2maxsw) is vital to accurately evaluate swimming performance. A need exists for reliable and valid swimming protocols that assess VO2maxsw in a flume environment. The purpose was to assess: (a) reliability and (b) “performance” validity of a VO2maxsw flume protocol using the 457-m freestyle pool performance swim (PS) test as the criterion. Nineteen males (n = 9) and females (n = 10) (age, 28.5 ± 8.3 years.; height, 174.7 ± 8.2 cm; mass, 72.9 ± 12.5 kg; %body fat, 21.4 ± 5.9) performed two flume VO2maxsw tests (VO2maxswA and VO2maxswB) and one PS test [457 m (469.4 ± 94.7 s)]. For test–retest reliability (Trials A vs. B), moderately strong relationships were established for VO2maxsw (mL·kg−1·min−1)(r= 0.628, p = 0.002), O2pulse (mL O2·beat−1)(r = 0.502, p = 0.014), VEmax (L·min−1) (r = 0.671, p = 0.001), final test time (sec) (0.608, p = 0.004), and immediate post-test blood lactate (IPE (BLa)) (0.716, p = 0.001). For performance validity, moderately strong relationships (p \u3c 0.05) were found between VO2maxswA (r =−0.648, p = 0.005), O2pulse (r= −0.623, p = 0.008), VEmax (r = −0.509 p = 0.037), and 457-m swim times. The swimming flume protocol examined is a reliable and valid assessment of VO2maxsw., and offers an alternative for military, open water, or those seeking complementary forms of training to improve swimming performance