Components of the communication system between infant and adult rodents based on ultrasonic vocalizations (USVs) of infants are analyzed. USVs are most often emitted from a pup lost outside the nest ...in response to changes of: (i) body temperature, (ii) contact with adults/littermates, (iii) handling, and (iv) smell. These changes modulate the state of arousal and the emotional/motivational states and, as a result, USVs are produced. Acoustic properties of USVs seem to reflect the degrees of changes in arousal and emotion/motivation. Adult rodents are aroused by perceiving the USVs, locate the sender and show a phonotaxic approach to the sender. Acoustic properties of USVs in the frequency and time domains are described based on which adult rodents discriminate the USVs from other ultrasounds and take the USVs or adequate models of them as preferred goals of their phonotaxic approach. The preferred approach to adequate USVs is modulated by emotions/motivations, the sex of the receiver, hormonal states, experience with pups and neurotransmitter systems of the brain. The phonotaxis can be understood as the appetitive component of a pup-caring instinct. The consummatory act of the instinct is the retrieval of the lost pup. This retrieval is independent of USV presence, but it closes the communication loop activated by the emission of USVs. Communication with USVs can be used as a tool to investigate genetic and brain mechanisms of behavioral control.
Adult mouse ultrasonic vocalizations (USVs) occur in multiple behavioral and stimulus contexts associated with various levels of arousal, emotion and social interaction. Here, in three experiments of ...increasing stimulus intensity (water; female urine; male interacting with adult female), we tested the hypothesis that USVs of adult males express the strength of arousal and emotion via different USV parameters (18 parameters analyzed). Furthermore, we analyzed two mouse lines with heterozygous Foxp2 mutations (R552H missense, S321X nonsense), known to produce severe speech and language disorders in humans. These experiments allowed us to test whether intact Foxp2 function is necessary for developing full adult USV repertoires, and whether mutations of this gene influence instinctive vocal expressions based on arousal and emotion. The results suggest that USV calling rate characterizes the arousal level, while sound pressure and spectrotemporal call complexity (overtones/harmonics, type of frequency jumps) may provide indices of levels of positive emotion. The presence of Foxp2 mutations did not qualitatively affect the USVs; all USV types that were found in wild‐type animals also occurred in heterozygous mutants. However, mice with Foxp2 mutations displayed quantitative differences in USVs as compared to wild‐types, and these changes were context dependent. Compared to wild‐type animals, heterozygous mutants emitted mainly longer and louder USVs at higher minimum frequencies with a higher occurrence rate of overtones/harmonics and complex frequency jump types. We discuss possible hypotheses about Foxp2 influence on emotional vocal expressions, which can be investigated in future experiments using selective knockdown of Foxp2 in specific brain circuits.
The complexity of male mouse ultrasounds increases with increasing positive emotion in both wild‐type and heterozygous Foxp2 mutant mice.
CO
2
, CH
4
, and N
2
O are recognised as the most important greenhouse gases, the concentrations of which increase rapidly through human activities. Space-borne integrated path differential ...absorption lidar allows global observations at day and night over land and water surfaces in all climates. In this study we investigate potential sources of measurement errors and compare them with the scientific requirements. Our simulations reveal that moderate-size instruments in terms of telescope aperture (0.5–1.5 m) and laser average power (0.4–4 W) potentially have a low random error of the greenhouse gas column which is 0.2% for CO
2
and 0.4% for CH
4
for soundings at 1.6 μm, 0.4% for CO
2
at 2.1 μm, 0.6% for CH
4
at 2.3 μm, and 0.3% for N
2
O at 3.9 μm. Coherent detection instruments are generally limited by speckle noise, while direct detection instruments suffer from high detector noise using current technology. The wavelength selection in the vicinity of the absorption line is critical as it controls the height region of highest sensitivity, the temperature cross-sensitivity, and the demands on frequency stability. For CO
2
, an error budget of 0.08% is derived from our analysis of the sources of systematic errors. Among them, the frequency stability of ± 0.3 MHz for the laser transmitter and spectral purity of 99.9% in conjunction with a narrow-band spectral filter of 1 GHz (FWHM) are identified to be challenging instrument requirements for a direct detection CO
2
system operating at 1.6 μm.
Active remote sensing is a promising technique to close the gaps that exist in global measurement of atmospheric carbon dioxide sources, sinks and fluxes. Several approaches are currently under ...development. Here, an experimental setup of an integrated path differential absorption lidar (IPDA) is presented, operating at 1.57 μm using direct detection. An injection seeded KTP-OPO system pumped by a Nd:YAG laser serves as the transmitter. The seed laser is actively stabilized by means of a CO
2
reference cell. The line-narrowed OPO radiation yields a high spectral purity, which is measured by means of a long path absorption cell. First measurements of diurnal variations of the atmospheric CO
2
mixing ratio using a topographic target were performed and show good agreement compared to simultaneously taken measurements of an in situ device. A further result is that the required power reference measurement of each laser pulse in combination with the spatial beam quality is a critical point of this method. The system described can serve as a testbed for further investigations of special features of the IPDA technique.
A high-performance airborne water vapor differential absorption lidar has been developed during the past years. This system uses a four-wavelength/three-absorption line measurement scheme in the ...935 nm H
2
O absorption band to cover the whole troposphere and lower stratosphere simultaneously. Additional high spectral resolution aerosol and depolarization channels allow precise aerosol characterization. This system is intended to demonstrate a future space-borne instrument. For the first time, it realizes an output power of up to 12 W at a high wall-plug efficiency using diode-pumped solid-state lasers and nonlinear conversion techniques. Special attention was given to a rugged optical layout. This paper describes the system layout and technical realization. Key performance parameters are given for the different subsystems.
Methane is the third most important greenhouse gas in the atmosphere after water vapour and carbon dioxide. A major handicap to quantify the emissions at the Earth's surface in order to better ...understand biosphere-atmosphere exchange processes and potential climate feedbacks is the lack of accurate and global observations of methane. Space-based integrated path differential absorption (IPDA) lidar has potential to fill this gap, and a Methane Remote Lidar Mission (MERLIN) on a small satellite in polar orbit was proposed by DLR and CNES in the frame of a German-French climate monitoring initiative. System simulations are used to identify key performance parameters and to find an advantageous instrument configuration, given the environmental, technological, and budget constraints. The sensitivity studies use representative averages of the atmospheric and surface state to estimate the measurement precision, i.e. the random uncertainty due to instrument noise. Key performance parameters for MERLIN are average laser power, telescope size, orbit height, surface reflectance, and detector noise. A modest-size lidar instrument with 0.45 W average laser power and 0.55 m telescope diameter on a 506 km orbit could provide 50-km averaged methane column measurement along the sub-satellite track with a precision of about 1% over vegetation. The use of a methane absorption trough at 1.65 μm improves the near-surface measurement sensitivity and vastly relaxes the wavelength stability requirement that was identified as one of the major technological risks in the pre-phase A studies for A-SCOPE, a space-based IPDA lidar for carbon dioxide at the European Space Agency. Minimal humidity and temperature sensitivity at this wavelength position will enable accurate measurements in tropical wetlands, key regions with largely uncertain methane emissions. In contrast to actual passive remote sensors, measurements in Polar Regions will be possible and biases due to aerosol layers and thin ice clouds will be minimised.
Heterozygous mutations of the human FOXP2 gene are implicated in a severe speech and language disorder. Aetiological mutations of murine Foxp2 yield abnormal synaptic plasticity and impaired ...motor‐skill learning in mutant mice, while knockdown of the avian orthologue in songbirds interferes with auditory‐guided vocal learning. Here, we investigate influences of two distinct Foxp2 point mutations on vocalizations of 4‐day‐old mouse pups (Mus musculus). The R552H missense mutation is identical to that causing speech and language deficits in a large well‐studied human family, while the S321X nonsense mutation represents a null allele that does not produce Foxp2 protein. We ask whether vocalizations, based solely on innate mechanisms of production, are affected by these alternative Foxp2 mutations. Sound recordings were taken in two different situations: isolation and distress, eliciting a range of call types, including broadband vocalizations of varying noise content, ultrasonic whistles and clicks. Sound production rates and several acoustic parameters showed that, despite absence of functional Foxp2, homozygous mutants could vocalize all types of sounds in a normal temporal pattern, but only at comparably low intensities. We suggest that altered vocal output of these homozygotes may be secondary to developmental delays and somatic weakness. Heterozygous mutants did not differ from wild‐types in any of the measures that we studied (R552H ) or in only a few (S321X ), which were in the range of differences routinely observed for different mouse strains. Thus, Foxp2 is not essential for the innate production of emotional vocalizations with largely normal acoustic properties by mouse pups.
Abstract
OBJECTIVE
To address to what extent central hemodynamic measurements, improve risk stratification, and determine outcome-based diagnostic thresholds, we constructed the International ...Database of Central Arterial Properties for Risk Stratification (IDCARS), allowing a participant-level meta-analysis. The purpose of this article was to describe the characteristics of IDCARS participants and to highlight research perspectives.
METHODS
Longitudinal or cross-sectional cohort studies with central blood pressure measured with the SphygmoCor devices and software were included.
RESULTS
The database included 10,930 subjects (54.8% women; median age 46.0 years) from 13 studies in Europe, Africa, Asia, and South America. The prevalence of office hypertension was 4,446 (40.1%), of which 2,713 (61.0%) were treated, and of diabetes mellitus was 629 (5.8%). The peripheral and central systolic/diastolic blood pressure averaged 129.5/78.7 mm Hg and 118.2/79.7 mm Hg, respectively. Mean aortic pulse wave velocity was 7.3 m per seconds. Among 6,871 participants enrolled in 9 longitudinal studies, the median follow-up was 4.2 years (5th–95th percentile interval, 1.3–12.2 years). During 38,957 person-years of follow-up, 339 participants experienced a composite cardiovascular event and 212 died, 67 of cardiovascular disease.
CONCLUSIONS
IDCARS will provide a unique opportunity to investigate hypotheses on central hemodynamic measurements that could not reliably be studied in individual studies. The results of these analyses might inform guidelines and be of help to clinicians involved in the management of patients with suspected or established hypertension.
Graphical Abstract
Graphical Abstract
At PTB, a new setup for the highly accurate topography measurement of nearly flat optical surfaces is now under construction. The so-called Deflectometric Flatness Reference (DFR) is designed to ...measure in the direct deflectometric mode by applying an autocollimator and a scanning pentaprism, and in the difference deflectometric mode corresponding to the Extended Shear Angle Difference (ESAD) principle invented by PTB. With the new DFR instrument, horizontally as well as vertically orientated specimens with dimensions of up to 1
m and a mass of up to 120
kg will be measurable. The design of the new instrument is supported by employing a comprehensive simulation environment developed for dimensional measuring machines. The mechanical and optical concept is illustrated together with the current design of the DFR setup. Results from the simulations are presented to derive requirements for tolerated mechanical stage deviations and alignment accuracies.
Doppler wind lidar (DWL) measurements by the fringe-imaging technique in front of aircrafts at flight speed require rapid processing of backscattered signals. We discuss the measurement principle to ...derive the 3D wind vector from three line-of-sight (LOS) measurements. Then we simulate realistic fringe patterns of a Fabry–Pérot-interferometer (FPI) on a 2D charge-coupled device (CCD) localized at the focal plane behind it, taking atmospheric and instrument properties like scattering and noise into account. A laser at 355 nm with pulse energies of 70 mJ at 100 Hz repetition rate and a range bin of only 10 m were assumed. This yields count rates of 24 (13) million photons per pulse at 56 (76) m distance and 8.5 km altitude that are distributed on a CCD with up to 960×780 pixels without intensification and therefore generate noisy pixel signals. We present two methods for the precise determination of the radii, i.e., wavelengths of these simulated FPI rings and show that both are suitable for eliminating pixel noise from the output and coping with fringe broadening by Rayleigh scattering. One of them proves to reach the accuracy necessary for LOS velocity measurements. A standard deviation of 2.5 m/s including center determination can be achieved with only 20 images to average. The bias is 7 m/s. For exactly known ring centers, each can be even better than 2 m/s. The methods could also be useful for high-resolution laser spectroscopy.
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