Multiple Signaling Functions Of Song In A Polymorphic Species With Alternative Reproductive Strategies

Vocal traits can be sexually selected to reflect male quality, but may also evolve to serve additional signaling functions. We used a long-term dataset to examine the signaling potential of song in dimorphic white-throated sparrows (Zonotrichia albicollis). We investigated whether song conveys multifaceted information about the vocalizing individual, including fitness, species identity, individual identity, and morph. We also evaluated whether song traits correlate differently with fitness in the two morphs, as the more promiscuous strategy of white, relative to tan, morph males might impose stronger sexual selection. Males with high song rates achieved higher lifetime reproductive success, and this pattern was driven by white morph males. In addition, males that sang songs with many notes survived longer, but this pattern was less robust. Thus, song traits reflect differences in fitness and may more strongly affect fitness in the white morph. Song frequency was unrelated to fitness, body size, or morph, but was individual specific and could signal individual identity. Songs of the two morphs displayed similar frequency ratios and bandwidths. However, tan morph males sang songs with longer first notes, fewer notes, and higher variability. Thus, song could be used in morph discrimination. Variation in frequency ratios between notes was low and could function in conspecific recognition, but pitch change dynamics did differ between four different song types observed. Our results support a multiple messages model for white-throated sparrow song, in which different song traits communicate discrete information about the vocalizing individual

Optimisation criterion for pulsatile timing: observation in the human fetus

Objectives: Pulsatile cardiac action is an energy consuming process. During pulse wave (PW) travel to the periphery, reflection back to the LV occurs. The concept of wave condition number, WCN, provides evidence that energy consumption of cardiac action is minimised when time of return Tr to LV takes a certain percentage of the cardiac cycle T. Our objective was to assess WCN and reflection timing Tr/T in the human fetus. Methods: Based on the WCN relation: WCN = HR×L/PWV, energy consumption of pulsatile LV action is optimised for WCN = 0.1 (HR: heart rate, L: effective aortic length, PWV: aortic PW velocity; Pahlevan 2014, 2020). Rearranging with Tr = 2L/PWV (figure) yield Tr/T = 0.2 as optimal reflection timing. To obtain Tr in the fetus by Doppler, hemodynamic modelling is required (figure): PWs arrive twice at cerebral circulation: 1st as a primary wave and 2nd after reflection and return. A systolic shoulder (S) in MCA Doppler (MCA‐S) represents this 2nd impulse and delay δt corresponds to Tr (Mills 1970). Results: Tr data of IUGR fetuses with MCA‐S were obtained by this method (Gonser 2018): Tr = 96 ± 15ms (GA 31 ± 3w). T = 423ms (FHR 140bpm) yield Tr/T = 96ms/423ms = 0.23, showing good agreement with optimal reflection timing of 20%, as suggested by the WCN. Conclusions: In spite of circulatory stress, IUGR fetuses maintain nearly optimal pulsatile timing, probably due to the priority of minimal energy consumption. Thus appearance of MCA‐S is not an artifact, but a sign of nearly optimal timed PW reflection

Forschung an einer Fachhochschule - ein siebenteiliger Bericht

Im Beziehungsgeflecht und Wettbewerb mit anderen Einrichtungen müssen Fachhochulen ihre Position auch als Stätten der Forschung beziehen. Anhand des Beispiels eines mehrjährigen Forschungsprojekts werden in sieben Aspekten die Besonderheiten von Fachhochschulforschung dargestellt, etwaige Problemlagen knapp beschrieben und das Entwicklungspotential herausgearbeitet. Dabei geht es u. a. um den Aufbau und Erhalt von Forschungsteams, um Publizität der Forschung oder um Konkurrenzverhältnisse auf Drittmittelmärkten. Schließlich plädiert der Beitrag für eine spezifische Forschungskultur von Fachhochschulen, die zur Identität solcher Einrichtungen wesentlich beitragen kann. 30.03.2012 | Nicole Gonser (Wien

The RunSmart Training Program: Effect on Oxygen Consumption and Lower Extremity Biomechanics During Running

As recreational running continues to gain popularity, more individuals are seeking ways to improve running performance. RunSmart is a running intervention program designed to enhance a runner’s form. In addition to correcting flaws in a runner’s form, RunSmart offers the opportunity for runners to continue a regular regimen while slowly integrating changes in form. The purpose of this case series was twofold: to determine if the RunSmart program coincides with improvements in oxygen consumption (VO2), a variable often associated with better running performance times, and to evaluate the RunSmart program in regard to enhancing gait biomechanics. Five recreational runners volunteered to participate in this program. Subjects initially reported to the clinic for an initial submaximal VO2 treadmill test and lower extremity biomechanical analysis. After the initial testing session, each subject attended one session of one-on-one individualized RunSmart instruction per week for 6 weeks. At the first RunSmart session, subjects received a biomechanical analysis to determine their foot strike pattern and areas of muscular weakness and range of motion limitations. Throughout the 6-week run-ning program, participants ran 5 days every week for predetermined times each day; 2 runs every week were designated as interval training runs. Subjects then underwent a follow-up submaximal VO2 treadmill test and lower extremity biomechanical analysis at the end of 6 weeks. Descriptive statistics were used to assess data pertaining to VO2 and biomechanical analysis and compare initial and follow-up testing sessions. Following completion of the RunSmart program, subjects demonstrated improvements in VO2 and also improved several biomechanical factors related to the lower extremity running gait. Based on the results from this case series, the RunSmart training program may have the potential to change a runner’s form and improve VO2, thus resulting in improved distance running times. However, this is speculation given the nonexperimental nature of this case series. Future research on this topic should include a greater number of participants in randomized controlled trials on injury prevention and running efficiency

Ion — particle interactions during particle formation and growth at a coniferous forest site in central Europe

In this work, we examined the interaction of ions and neutral particles during atmospheric new particle formation (NPF) events. The analysis is based on simultaneous field measurements of atmospheric ions and total particles using a neutral cluster and air ion spectrometer (NAIS) across the diameter range 2–25 nm. The Waldstein research site is located in a spruce forest in NE Bavaria, Southern Germany, known for enhanced radon concentrations, presumably leading to elevated ionization rates. Our observations show that the occurrence of the ion nucleation mode preceded that of the total particle nucleation mode during all analyzed NPF events. The time difference between the appearance of 2 nm ions and 2 nm total particles was typically about 20 to 30 min. A cross correlation analysis showed a rapid decrease of the time difference between the ion and total modes during the growth process. Eventually, this time delay vanished when both ions and total particles did grow to larger diameters. Considering the growth rates of ions and total particles separately, total particles exhibited enhanced growth rates at diameters below 15 nm. This observation cannot be explained by condensation or coagulation, because these processes would act more efficiently on charged particles compared to neutral particles. To explain our observations, we propose a mechanism including recombination and attachment of continuously present cluster ions with the ion nucleation mode and the neutral nucleation mode, respectively

Room Temperature Uniaxial Magnetic Anisotropy Induced By Fe‐Islands in the InSe Semiconductor Van Der Waals Crystal

The controlled manipulation of the spin and charge of electrons in a semiconductor has the potential to create new routes to digital electronics beyond Moore’s law, spintronics, and quantum detection and imaging for sensing applications. These technologies require a shift from traditional semiconducting and magnetic nanostructured materials. Here, a new material system is reported, which comprises the InSe semiconductor van der Waals crystal that embeds ferromagnetic Fe-islands. In contrast to many traditional semiconductors, the electronic properties of InSe are largely preserved after the incorporation of Fe. Also, this system exhibits ferromagnetic resonances and a large uniaxial magnetic anisotropy at room temperature, offering opportunities for the development of functional devices that integrate magnetic and semiconducting properties within the same material system