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Metal hydroborates and their derivatives have been receiving attention as potential solid-state ion conductors for battery applications owing to their impressive electrochemical and mechanical characteristics. However, to date only a fraction of these compounds has been investigated as solid-state electrolytes. Here, MB12H11NH3 (M = Li and Na) hydroborates are synthesized and investigated as electrolyte materials for all-solid-state batteries. The room temperature #945;-NaB12H11NH3 was structurally solved in P212121 (a = 7.1972(3) Å, b = 9.9225(4) Å, and c = 14.5556(5) Å). It shows a polymorphic structural transition near 140 °C to cubic Fm3m. LiB12H11NH3 and NaB12H11NH3 exhibit cationic conductivities of σ(Li+) = 3.0 × 10-4 S cm-1 and σ(Na+) = 1.2 × 10-4 S cm-1 at 200 °C. Hydration is found to improve ionic conductivity of the hydroborates. It is presumed that modest ionic conductivities could be due to a lack of significant reorientational dynamics in the crystal structure resulting from the presence of the bulky -NH3 group in the anion. [ABSTRACT FROM AUTHOR]

Significant land uplift and horizontal motions have been recorded with Global Navigation Satellite Systems (GNSS) in areas such as Alaska, Iceland and the Northern Antarctic Peninsula (NAP) as a result of Glacial Isostatic Adjustment (GIA) due to ice melt after the Little Ice Age. Here, analysis of horizontal displacement rates can be of extra importance, as they are more sensitive to Earth properties in shallower layers than vertical displacement rates. Proper modelling of horizontal displacement rates with dedicated GIA models requires a spherical Earth with compressible rheology. However, in these small areas, the used GIA models are often incompressible using a Cartesian geometry to ease computation and in some cases allow for lateral viscosity changes or more complex rheology. We investigate the validity of modelled horizontal displacement rates using different approximations, that is using spherical or Cartesian Earth structures, and incompressible, material compressible or compressible rheology. Although the lack of self-gravity and sphericity compensate each other in the vertical, this is less the case for the horizontal. For a disc ice sheet with a radius just over 200 km and a thickness of 1000 m, differences due to sphericity are minimal and the modelled horizontal displacement rates of compressible Cartesian models differ from those simulated by a compressible spherical model by 0.63 mm a−1. Thus, compressible Cartesian GIA models can be applied for modelling horizontal displacement rates of small ice sheets like those in Alaska, Iceland and NAP. Unfortunately, the implementation of compressibility in Abaqus that we use here cannot be extended to spherical models as gravity can not be specified for a spherical body. Other modelling approaches are recommended in such cases. [ABSTRACT FROM AUTHOR]

The article examines how primates contribute to understanding the evolution of human speech, highlighting that speech development involves more than just a suitable brain and vocal anatomy. Topics discussed include the historical view of primate vocalizations as irrelevant to speech evolution, recent findings of speech-like features in primates, and the impact of social complexity on the development of human language.

The article focuses on the investigation of the neural mechanisms underlying the coordination of vocalization and respiration in mice, revealing a laryngeal premotor circuit critical for respiratory-vocal coupling. It mentions the study, using genetic tools and optogenetic manipulation, identifies the nucleus retroambiguus (RAm) as part of the vocal pattern-generating network.

Empowering leadership is an important influence on team effectiveness. This makes the question of what the antecedents of team empowering leadership are an important issue to consider. To address this question, we propose a motivated information processing perspective that holds that engaging in empowering leadership is based on social information processing, and that there are individual differences in how elaborate that information processing is. We argue that a key consideration in shifting control from the leader to the team is the extent to which empowering leadership is driven by leaders' consideration of their trust in the team (i.e., an instance of social information processing), and that leader need for closure (a trait capturing the disposition to carefully consider decisions and actions) moderates the relationship between leader trust in team and empowering leadership. A survey of N = 156 work teams supported these hypotheses. [ABSTRACT FROM AUTHOR]

• Marmoset monkeys are capable of modulating the acoustic structure of ongoing calls. • Marmoset calls are built of many sequentially uttered stereotyped brief units. • Monkey calls are produced by a brainstem-based vocal pattern-generating network. • Audio-vocal integration mechanisms are present at cortical and subcortical levels. Marmoset monkeys are known for their rich vocal repertoire. However, the underlying call production mechanisms remain unclear. By showing that marmoset moneys are capable of interrupting and modulating ongoing vocalizations, recent studies in marmoset monkeys challenged the decades-old concepts of primate vocal pattern generation that suggested that monkey calls consist of one discrete call pattern. The current article will present a revised version of the brainstem vocal pattern-generating network in marmoset monkeys that is capable of responding to perturbing auditory stimuli with rapid modulatory changes of the acoustic call structure during ongoing calls. These audio-vocal integration processes might potentially happen at both the cortical and subcortical brain level. [ABSTRACT FROM AUTHOR]

Many fouls committed in football (called soccer in some countries) are ambiguous, and there is no objective way of determining who is the "true" perpetrator or the "true" victim. Consequently, fans as well as referees often rely on a variety of decision cues when judging such foul situations. Based on embodiment research, which links perceptions of height to concepts of strength, power, and aggression, we argue that height is going to be one of the decision cues used. As a result, people are more likely to attribute a foul in an ambiguous tackle situation to the taller of two players. We find consistent support for our hypothesis, not only in field data spanning the last seven UEFA Champions League and German Bundesliga seasons, as well as the last three FIFA World Cups, but also in two experimental studies. The resulting dilemma for refereeing in practice is discussed. [ABSTRACT FROM AUTHOR]

In most European countries the booster vaccine doses against Tick-Borne Encephalitis (TBE) are indicated every 3 or 5 years depending on the number of previous doses and the age of the person. That means more frequent boosters than with any other vaccine. There is evidence that this results in low compliance with recommendations. Concerned about a low TBE vaccination coverage in Swiss endemic regions, the Swiss Federal Office of Public Health (SFOPH) in 2006 decided to recommend booster doses only every 10 years for all age groups after completion of the primary immunization. This amendment combined with intensified recommendations resulted in a sharp increase of the proportion of the immunized population. To ascertain that the amended recommendations would not result in increased risk of breakthroughs the SFOPH started to annually monitor TBE vaccine failures with particular attention to older age groups. Additionally, a matched case-control study evaluated TBE vaccine effectiveness by booster interval. Surveillance data of the SFOPH demonstrates that in the initial 3 years after the last vaccine dose the annual breakthrough incidence was 7.7 (95% CI 5.0-11.7), while in the years 4 to 10 it was 5.4 (3.9-7.5) per year. The case-control study demonstrated a vaccine effectiveness of 91.6 (95% CI 88.4-94.0)% when the most recent dose was received <5 years, of 95.2 (92.4-97.0)% among those with the last booster dose 5 to 10 years, and of 98.5 (96.8-99.2)% when the most recent dose was received >10 years prior to infection. Both studies indicate that there is not even a trend indicating an increase in vaccine failures with longer booster intervals. Obviously, cell mediated immunity assures protection in above 95% despite of declining antibodies over time. Thus, the cumbersome TBE vaccine schedules should be reconsidered. Longer intervals will result in increased acceptability, lower costs and thus in a public health success. [ABSTRACT FROM AUTHOR]

Songbirds are renowned for their acoustically elaborate songs. However, it is unclear whether songbirds can cognitively control their vocal output. Here, we show that crows, songbirds of the corvid family, can be trained to exert control over their vocalizations. In a detection task, three male carrion crows rapidly learned to emit vocalizations in response to a visual cue with no inherent meaning (go trials) and to withhold vocalizations in response to another cue (catch trials). Two of these crows were then trained on a go/nogo task, with the cue colors reversed, in addition to being rewarded for withholding vocalizations to yet another cue (nogo trials). Vocalizations in response to the detection of the go cue were temporally precise and highly reliable in all three crows. Crows also quickly learned to withhold vocal output in nogo trials, showing that vocalizations were not produced by an anticipation of a food reward in correct trials. The results demonstrate that corvids can volitionally control the release and onset of their vocalizations, suggesting that songbird vocalizations are under cognitive control and can be decoupled from affective states. [ABSTRACT FROM AUTHOR]

Taking turns plays an important role in primate communication and involves individuals producing species-specific calls in response to conspecific vocalizations. Recent studies have revealed that marmoset monkeys are an ideal primate model system to investigate vocal turn-taking behavior and the corresponding sensory-motor interactions. However, it is largely unknown how external factors such as conspecific call latency influence this vocal behavior. Using interactive playback, we systematically answered vocalizations of monkeys with either short- or long-call response latencies. By placing marmosets in these different behavioral conditions, we demonstrate that vocal turn taking is a robust behavior with only minor condition-dependent changes that is exhibited not only in the range of species-specific call latencies of vocal partners but also in conditions well outside natural behavioral boundaries. We find that specific features of vocal performance such as call response rates and call sequences remain surprisingly stable, whereas others such as turn-taking rates and response latencies exhibit condition-dependent differences during this behavior. These condition-dependent modulations suggest that a combination of flexible and more rigid mechanisms control marmoset vocal turn-taking behavior. [ABSTRACT FROM AUTHOR]

Highlights • We recorded in the brainstem of vocalizing marmoset monkeys with laminar probes. • The system enables flexible positioning of the probes within an implanted chamber. • Single-unit activity was simultaneously recorded from a high number of sites. • Single unit activity can be recorded with the implanted probe over several weeks. • Several probes can be consecutively implanted within a single animal. Abstract Background Chronic recordings with multi-electrode arrays are widely used to study neural networks underlying complex primate behaviors. Most of these systems are designed for studying neural activity in the cortical hemispheres resulting in a lack of devices being capable of simultaneously recording from ensembles of neurons in deep brainstem structures. However, to fully understand complex behavior, it is fundamental to also decipher the intrinsic mechanisms of the underlying motor pattern generating circuits in the brainstem. New method We report a light-weight system that simultaneously measures single-unit activity from a large number of recording sites in the brainstem of marmoset monkeys. It includes a base chamber fixed to the animal's skull and a removable upper chamber that can be semi-chronically mounted to the base chamber to flexibly position an embedded micro-drive containing a 32-channel laminar probe to record from various positions within the brainstem for several weeks. Results The current system is capable of simultaneously recording stable single-unit activity from a large number of recording sites in the brainstem of vocalizing marmoset monkeys. Comparison with existing methods To the best of our knowledge, chronic systems to record from deep brainstem structures with multi-site laminar probes in awake, behaving monkeys do not yet exist. Conclusions The semi-chronic implantation of laminar electrodes into the brainstem of behaving marmoset monkeys opens new research possibilities in fully understanding the neural mechanisms underlying complex behaviors in marmoset monkeys. [ABSTRACT FROM AUTHOR]

Understanding the neural underpinnings of vocal–motor control in humans and other animals remains a major challenge in neurobiology. The Lombard effect – a rise in call amplitude in response to background noise – has been demonstrated in a wide range of vertebrates. Here, we review both behavioral and neurophysiological data and propose that the Lombard effect is driven by a subcortical neural network, which can be modulated by cortical processes. The proposed framework offers mechanistic explanations for two fundamental features of the Lombard effect: its widespread taxonomic distribution across the vertebrate phylogenetic tree and the widely observed variations in compensation magnitude. We highlight the Lombard effect as a model behavioral paradigm for unraveling some of the neural underpinnings of audiovocal integration. Highlights The Lombard effect is a phylogenetically ancient audiovocal phenomenon that may have emerged ∼450 million years ago. The Lombard effect is elicited by a subcortical network that processes acoustic features of stimuli, such as amplitude, frequency, and duration. The Lombard effect is better explained by the SNR between a subject's vocalization and ambient noise, than by the amplitude of ambient noise per se. The physiological SNR of the auditory system is influenced by various parameters such as amplitude, call frequency, and duration, and Lombard effect for a given vocalization is determined by these parameters collectively. Cortical networks can play a modulatory role in the Lombard effect, and may differentially influence the Lombard effect across groups of animals that differ with respect to neuroanatomical structure and organization. The Lombard effect serves as a valuable behavioral paradigm to unravel the neural underpinnings of audiovocal integration, which is essential to many other aspects of vocal control. [ABSTRACT FROM AUTHOR]

Benzimidazoles (BZ) are essential components of the limited chemotherapeutic arsenal available to control the global burden of parasitic nematodes. The emerging threat of BZ resistance among multiple nematode species necessitates the development of novel strategies to identify genetic and molecular mechanisms underlying this resistance. All detection of parasitic helminth resistance to BZ is focused on the genotyping of three variant sites in the orthologs of the β-tubulin gene found to confer resistance in the free-living nematode Caenorhabditis elegans. Because of the limitations of laboratory and field experiments in parasitic nematodes, it is difficult to look beyond these three sites to identify additional mechanisms that might contribute to BZ resistance in the field. Here, we took an unbiased genome-wide mapping approach in the free-living nematode species C. elegans to identify the genetic underpinnings of natural resistance to the commonly used BZ, albendazole (ABZ). We found a wide range of natural variation in ABZ resistance in natural C. elegans populations. In agreement with known mechanisms of BZ resistance in parasites, we find that a majority of the variation in ABZ resistance among wild C. elegans strains is caused by variation in the β-tubulin gene ben-1. This result shows empirically that resistance to ABZ naturally exists and segregates within the C. elegans population, suggesting that selection in natural niches could enrich for resistant alleles. We identified 25 distinct ben-1 alleles that are segregating at low frequencies within the C. elegans population, including many novel molecular variants. Population genetic analyses indicate that ben-1 variation arose multiple times during the evolutionary history of C. elegans and provide evidence that these alleles likely occurred recently because of local selective pressures. Additionally, we find purifying selection at all five β-tubulin genes, despite predicted loss-of-function variants in ben-1, indicating that BZ resistance in natural niches is a stronger selective pressure than loss of one β-tubulin gene. Furthermore, we use genome-editing to show that the most common parasitic nematode β-tubulin allele that confers BZ resistance, F200Y, confers resistance in C. elegans. Importantly, we identified a novel genomic region that is correlated with ABZ resistance in the C. elegans population but independent of ben-1 and the other β-tubulin loci, suggesting that there are multiple mechanisms underlying BZ resistance. Taken together, our results establish a population-level resource of nematode natural diversity as an important model for the study of mechanisms that give rise to BZ resistance. [ABSTRACT FROM AUTHOR]

Monkey vocalization is a complex behavioral pattern, which is flexibly used in audio-vocal communication. A recently proposed dual neural network model suggests that cognitive control might be involved in this behavior, originating from a frontal cortical network in the prefrontal cortex and mediated via projections from the rostral portion of the ventral premotor cortex (PMvr) and motor cortex to the primary vocal motor network in the brainstem. For the rapid adjustment of vocal output to external acoustic events, strong interconnections between vocal motor and auditory sites are needed, which are present at cortical and subcortical levels. However, the role of the PMvr in audio-vocal integration processes remains unclear. In the present study, single neurons in the PMvr were recorded in rhesus monkeys ( Macaca mulatta ) while volitionally producing vocalizations in a visual detection task or passively listening to monkey vocalizations. Ten percent of randomly selected neurons in the PMvr modulated their discharge rate in response to acoustic stimulation with species-specific calls. More than four-fifths of these auditory neurons showed an additional modulation of their discharge rates either before and/or during the monkeys' motor production of the vocalization. Based on these audio-vocal interactions, the PMvr might be well positioned to mediate higher order auditory processing with cognitive control of the vocal motor output to the primary vocal motor network. Such audio-vocal integration processes in the premotor cortex might constitute a precursor for the evolution of complex learned audio-vocal integration systems, ultimately giving rise to human speech. [ABSTRACT FROM AUTHOR]

Although much work is being done to develop new treatments, research and knowledge regarding factors underlying implant‐related microbial colonization leading to infection are less comprehensive. Presence of microorganisms in and around implants clinically characterized as uninfected remains unknown. The objective of this study was to detect and identify bacteria and fungi on implants from various groups of patients with no prior indications of implant related infections. Patient samples (implants and tissue) were collected from five different hospitals in the Capital region of Denmark. By in‐depth microbiological detection methods, we examined the prevalence of bacteria and fungi on 106 clinically uninfected implants from four patient groups (aseptic loosening, healed fractures, craniofacial complications and recently deceased). Of 106 clinically uninfected implants and 39 negative controls investigated, 66% were colonized by bacteria and 40% were colonized by fungi (p < 0.0001 compared to negative controls). A large number of microbes were found to colonize the implants, however, the most prevalent microbes present were not common aetiological agents of implant infections. The findings indicate that implants provide a distinct niche for microbial colonization. These data have broad implications for medical implant recipients, as well as for supporting the idea that the presence of foreign objects in the body alters the human microbiome by providing new colonization niches. [ABSTRACT FROM AUTHOR]

The article focuses on a study regarding the limitation of parental interaction during vocal development as it affects acoustic call structure in marmoset monkeys. Topics discussed include social interaction has a direct impact not only on the maturation of the vocal behavior but also on acoustic call structures during vocal development, systematic differences in call entropy and social interaction in proper primate vocal development.

Uncertainty about the future course of the economy is a potential driver of aggregate fluctuations. To identify the distinct dimensions of uncertainty in the macroeconomy, we construct a large dataset covering all types of economic uncertainty. We then identify two fundamental factors that account for the common dynamics in this dataset. These factors are interpreted as macroeconomic uncertainty. The first factor captures business cycle uncertainty, while the second factor represents oil and commodity price uncertainty. While both types of uncertainty generate a decline in output, time-varying oil and commodity price uncertainty is more important for fluctuations in real activity. However, nonlinearities seem to amplify the effect of business cycle uncertainty during the global financial crisis. ( JEL C32, C38, E32) [ABSTRACT FROM AUTHOR]

Explaining the evolution of speech and language poses one of the biggest challenges in biology. We propose a dual network model that posits a volitional articulatory motor network (VAMN) originating in the prefrontal cortex (PFC; including Broca's area) that cognitively controls vocal output of a phylogenetically conserved primary vocal motor network (PVMN) situated in subcortical structures. By comparing the connections between these two systems in human and nonhuman primate brains, we identify crucial biological preadaptations in monkeys for the emergence of a language system in humans. This model of language evolution explains the exclusiveness of non-verbal communication sounds (e.g., cries) in infants with an immature PFC, as well as the observed emergence of non-linguistic vocalizations in adults after frontal lobe pathologies. [ABSTRACT FROM AUTHOR]

Background: Travel health risks documented by questionnaire surveys obtained (e.g., during homebound flights) are incomplete since they miss most patients who need to be repatriated.Methods: All patient claim files were reviewed from 1997 to 1998, of the largest Swiss travel insurance company.Results: Among 242 claims, 69.4% were due to illness, 30.6% due to accidents; infections were the most frequent illnesses, the extremities were the most frequently traumatized part of the body. Although the illness-to-accident ratio was 1:5 in industrialized countries and the Caribbean, it exceeded 3:0 in some developing regions. Accident proneness was noted in the first week abroad.Conclusion: Even if no denominator data are available, this analysis offers an insight in travel health risks, allowing comparison of the occurrences of very different, serious, health problems abroad. [ABSTRACT FROM AUTHOR]

The evolutionary origins of human language are obscured by the scarcity of essential linguistic characteristics in non-human primate communication systems. Volitional control of vocal utterances is one such indispensable feature of language. We investigated the ability of two monkeys to volitionally utter species-specific calls over many years. Both monkeys reliably vocalized on command during juvenile periods, but discontinued this controlled vocal behavior in adulthood. This emerging disability was confined to volitional vocal production, as the monkeys continued to vocalize spontaneously. In addition, they continued to use hand movements as instructed responses during adulthood. This greater vocal flexibility of monkeys early in ontogeny supports the neoteny hypothesis in human evolution. This suggests that linguistic capabilities were enabled via an expansion of the juvenile period during the development of humans. [ABSTRACT FROM AUTHOR]

Complex audio-vocal integration systems depend on a strong interconnection between the auditory and the vocal motor system. To gain cognitive control over audio-vocal interaction during vocal motor control, the PFC needs to be involved. Neurons in the ventrolateral PFC (VLPFC) have been shown to separately encode the sensory perceptions and motor production of vocalizations. It is unknown, however, whether single neurons in the PFC reflect audio-vocal interactions. We therefore recorded single-unit activity in the VLPFC of rhesus monkeys (Macaca mulatta) while they produced vocalizations on command or passively listened to monkey calls. We found that 12% of randomly selected neurons in VLPFC modulated their discharge rate in response to acoustic stimulation with species-specific calls. Almost three-fourths of these auditory neurons showed an additional modulation of their discharge rates either before and/or during the monkeys' motor production of vocalization. Based on these audio-vocal interactions, the VLPFC might be well positioned to combine higher order auditory processing with cognitive control of the vocal motor output. Such audio-vocal integration processes in the VLPFC might constitute a precursor for the evolution of complex learned audio-vocal integration systems, ultimately giving rise to human speech. [ABSTRACT FROM AUTHOR]

In this response to commentaries, we revisit the two main arguments of our target article. Based on data drawn from a variety of research areas – vocal behavior in nonhuman primates, speech physiology and pathology, neurobiology of basal ganglia functions, motor skill learning, paleoanthropological concepts – the target article, first, suggests a two-stage model of the evolution of the crucial motor prerequisites of spoken language within the hominin lineage: (1) monosynaptic refinement of the projections of motor cortex to brainstem nuclei steering laryngeal muscles, and (2) subsequent “vocal-laryngeal elaboration” of cortico-basal ganglia circuits, driven by human-specific FOXP2 mutations. Second, as concerns the ontogenetic development of verbal communication, age-dependent interactions between the basal ganglia and their cortical targets are assumed to contribute to the time course of the acquisition of articulate speech. Whereas such a phylogenetic reorganization of cortico-striatal circuits must be considered a necessary prerequisite for ontogenetic speech acquisition, the 30 commentaries – addressing the whole range of data sources referred to – point at several further aspects of acoustic communication which have to be added to or integrated with the presented model. For example, the relationships between vocal tract movement sequencing – the focus of the target article – and rhythmical structures of movement organization, the connections between speech motor control and the central-auditory and central-visual systems, the impact of social factors upon the development of vocal behavior (in nonhuman primates and in our species), and the interactions of ontogenetic speech acquisition – based upon FOXP2-driven structural changes at the level of the basal ganglia – with preceding subvocal stages of acoustic communication as well as higher-order (cognitive) dimensions of phonological development. Most importantly, thus, several promising future research directions unfold from these contributions – accessible to clinical studies and functional imaging in our species as well as experimental investigations in nonhuman primates. [ABSTRACT FROM PUBLISHER]

Any account of “what is special about the human brain” (Passingham 2008) must specify the neural basis of our unique ability to produce speech and delineate how these remarkable motor capabilities could have emerged in our hominin ancestors. Clinical data suggest that the basal ganglia provide a platform for the integration of primate-general mechanisms of acoustic communication with the faculty of articulate speech in humans. Furthermore, neurobiological and paleoanthropological data point at a two-stage model of the phylogenetic evolution of this crucial prerequisite of spoken language: (i) monosynaptic refinement of the projections of motor cortex to the brainstem nuclei that steer laryngeal muscles, presumably, as part of a “phylogenetic trend” associated with increasing brain size during hominin evolution; (ii) subsequent vocal-laryngeal elaboration of cortico-basal ganglia circuitries, driven by human-specific FOXP2 mutations.;>This concept implies vocal continuity of spoken language evolution at the motor level, elucidating the deep entrenchment of articulate speech into a “nonverbal matrix” (Ingold 1994), which is not accounted for by gestural-origin theories. Moreover, it provides a solution to the question for the adaptive value of the “first word” (Bickerton 2009) since even the earliest and most simple verbal utterances must have increased the versatility of vocal displays afforded by the preceding elaboration of monosynaptic corticobulbar tracts, giving rise to enhanced social cooperation and prestige. At the ontogenetic level, the proposed model assumes age-dependent interactions between the basal ganglia and their cortical targets, similar to vocal learning in some songbirds. In this view, the emergence of articulate speech builds on the “renaissance” of an ancient organizational principle and, hence, may represent an example of “evolutionary tinkering” (Jacob 1977). [ABSTRACT FROM PUBLISHER]

One of the most efficient mechanisms to optimize signal-to-noise ratios is the Lombard effect - an involuntary rise in call amplitude due to ambient noise. It is often accompanied by changes in the spectro-temporal composition of calls. We examined the effects of broadband-filtered noise on the spectro-temporal composition of horseshoe bat echolocation calls, which consist of a constant-frequency component and initial and terminal frequency-modulated components. We found that the frequency-modulated components became larger for almost all noise conditions, whereas the bandwidth of the constant-frequency component increased only when broadband-filtered noise was centered on or above the calls' dominant or fundamental frequency. This indicates that ambient noise independently modifies the associated acoustic parameters of the Lombard effect, such as spectro-temporal features, and could significantly affect the bat's ability to detect and locate targets. Our findings may be of significance in evaluating the impact of environmental noise on echolocation behavior in bats. [ABSTRACT FROM AUTHOR]

Awake, behaving rhesus monkeys are widely used in neurophysiological research. Neural signals are typically measured from monkeys trained with operant conditioning techniques to perform a variety of behavioral tasks in exchange for rewards. Over the past years, monkeys' psychological well-being during experimentation has become an increasingly important concern. We suggest objective criteria to explore whether training sessions during which the monkeys work under controlled water intake over many days might affect their behavior. With that aim, we analyzed a broad range of species-specific behaviors over several months (‘ethogram’) and used these ethograms as a proxy for the monkeys' well-being. Our results show that monkeys' behavior during training sessions is unaffected by the duration of training-free days in-between. Independently of the number of training-free days (two or nine days) with ad libitum food and water supply, the monkeys were equally active and alert in their home group cages during training phases. This indicates that the monkeys were well habituated to prolonged working schedules and that their well-being was stably ensured during the training sessions. [ABSTRACT FROM PUBLISHER]

B Background: b Tick-borne encephalitis (TBE) is associated with sequelae the proportion increasing with growing age. However, recent follow-up surveys identified a substantial proportion of children with long-term cognitive impairment up to 17 years subsequent to TBE infection. B Conclusion: b Even if TBE infection is milder in pediatric populations, TBE often results in a seriously underestimated long-term cognitive impairment. [Extracted from the article]

Background: Mice produce ultrasonic vocalizations in various inter-individual encounters and with high call rates. However, it is so far virtually unknown how these vocal patterns are generated. On the one hand, these vocal patterns could be embedded into the normal respiratory cycle, as happens in bats and other mammals that produce similar call rates and frequencies. On the other, mice could possess distinct vocal pattern generating systems that are capable of modulating the respiratory cycle, which is what happens in non-human and human primates. In the present study, we investigated the temporal call patterns of two different mammalian species, bats and mice, in order to differentiate between these two possibilities for mouse vocalizations. Our primary focus was on comparing the mechanisms for the production of rapid, successive ultrasound calls of comparable frequency ranges in the two species. Results: We analyzed the temporal call pattern characteristics of mice, and we compared these characteristics to those of ultrasonic echolocation calls produced by horseshoe bats. We measured the distributions of call durations, call intervals, and inter-call intervals in the two species. In the bat, and consistent with previous studies, we found that call duration was independent of corresponding call intervals, and that it was negatively correlated with the corresponding inter-call interval. This indicates that echolocation call production mechanisms in the bat are highly correlated with the respiratory cycle. In contrast, call intervals in the mouse were directly correlated with call duration. Importantly, call duration was not, or was only slightly, correlated with inter-call intervals, consistent with the idea that vocal production in the mouse is largely independent of the respiratory cycle. Conclusions: Our findings suggest that ultrasonic vocalizations in mice are produced by call-pattern generating mechanisms that seem to be similar to those that have been found in primates. This is in contrast to the production mechanisms of ultrasonic echolocation calls in horseshoe bats. These results are particularly interesting, especially since mouse vocalizations have recently attracted increased attention as potential indicators for the degree of progression of several disease patterns in mouse models for neurodegenerative and neurodevelopmental disorders of humans. [ABSTRACT FROM AUTHOR]

Whether nonhuman primates can decouple their innate vocalizations from accompanied levels of arousal or specific events in the environment to achieve cognitive control over their vocal utterances has been a matter of debate for decades. We show that rhesus monkeys can be trained to elicit different call types on command in response to arbitrary visual cues. Furthermore, we report that a monkey learned to switch between two distinct call types from trial to trial in response to different visual cues. A controlled behavioral protocol and data analysis based on signal detection theory showed that noncognitive factors as a cause for the monkeys' vocalizations could be excluded. Our findings also suggest that monkeys also have rudimentary control over acoustic call parameters. These findings indicate that monkeys are able to volitionally initiate their vocal production and, therefore, are able to instrumentalize their vocal behavior to perform a behavioral task successfully. [ABSTRACT FROM AUTHOR]

The Lombard effect, an involuntary rise in call amplitude in response to masking ambient noise, represents one of the most efficient mechanisms to optimize signal-to-noise ratio. The Lombard effect occurs in birds and mammals, including humans, and is often associated with several other vocal changes, such as call frequency and duration. Most studies, however, have focused on noise- dependent changes in call amplitude. It is therefore still largely unknown how the adaptive changes in call amplitude relate to associated vocal changes such as frequency shifts, how the un- derlying mechanisms are linked, and if auditory feedback from the changing vocal output is needed. Here, we examined the Lombard effect and the associated changes in call frequency in a highly vocal mammal, echolocating horseshoe bats. We analyzed how bandpass-filtered noise (BEN; bandwidth 20 kHz) affected their echolocation behavior when BEN was centered on different frequencies within their hearing range. Call amplitudes increased only when BFN was centered on the dominant frequency component of the bats' calls. In contrast, call frequencies increased for all but one BEN center frequency tested. Both amplitude and frequency rises were extremely fast and occurred in the first call uttered after noise onset, suggesting that no auditory feedback was required. The different effects that varying the BFN center frequency had on amplitude and frequency rises indicate different neural circuits and/or mechanisms underlying these changes. [ABSTRACT FROM AUTHOR]

A profusion of articles have been published on the accuracy and uses of interferon-gamma releasing assays. Here we review the clinical applications, advantages, and limitations of the tuberculin skin test and interferon-gamma release assays and provide an overview of the most recent systematic reviews conducted for different indications for the use of these tests. We conclude that both tests are accurate to detect latent tuberculosis, although interferon-gamma release assays have higher specificity than tuberculin skin testing in BCG-vaccinated populations, particularly if BCG is received after infancy. However, both tests perform poorly to predict risk for progression to active tuberculosis. Interferon-gamma release assays have significant limitations in serial testing because of spontaneous variability and lack of a validated definition of conversion and reversion, making it difficult for clinicians to interpret changes in category (conversions and reversions). So far, the most important clinical evidence, that is, that isoniazid preventive therapy reduces the risk for progression to disease, has been produced only in tuberculin skin test-positive individuals. [ABSTRACT FROM AUTHOR]

ABSTRACT We present a detailed comparison of fundamental dark matter halo properties retrieved by a substantial number of different halo finders. These codes span a wide range of techniques including friends-of-friends, spherical-overdensity and phase-space-based algorithms. We further introduce a robust (and publicly available) suite of test scenarios that allow halo finder developers to compare the performance of their codes against those presented here. This set includes mock haloes containing various levels and distributions of substructure at a range of resolutions as well as a cosmological simulation of the large-scale structure of the universe. All the halo-finding codes tested could successfully recover the spatial location of our mock haloes. They further returned lists of particles (potentially) belonging to the object that led to coinciding values for the maximum of the circular velocity profile and the radius where it is reached. All the finders based in configuration space struggled to recover substructure that was located close to the centre of the host halo, and the radial dependence of the mass recovered varies from finder to finder. Those finders based in phase space could resolve central substructure although they found difficulties in accurately recovering its properties. Through a resolution study we found that most of the finders could not reliably recover substructure containing fewer than 30-40 particles. However, also here the phase-space finders excelled by resolving substructure down to 10-20 particles. By comparing the halo finders using a high-resolution cosmological volume, we found that they agree remarkably well on fundamental properties of astrophysical significance (e.g. mass, position, velocity and peak of the rotation curve). We further suggest to utilize the peak of the rotation curve, vmax, as a proxy for mass, given the arbitrariness in defining a proper halo edge. [ABSTRACT FROM AUTHOR]

Social psychology is concerned with people interacting as members of social groups. Corporate mergers provide an interesting field to apply social psychological theory in practice and also provide a context for the test and development of such theories. Mergers and acquisitions have been shown to often fail their financial and other strategic aims – one key reason for this failure is that human resources, that is, the needs of employees involved in the merger, are often considered less important than legal, technological or other factors by senior managers. In particular, it is often the merger’s impact on employee identities as members of the pre-merger organizations and its consideration by change leaders that determines the merger’s failure or success. The article ‘Social Identity and Corporate Mergers’ utilizes a social identity approach to analyze the problem zones of mergers and we provide research suggesting how to lead a merger into success. In particular, leaders should provide reasons for why the merger is necessary, they should demonstrate actual and future continuity to reduce uncertainties due to the merger situation and leaders should pay attention to status differentials (e.g., between employees of the acquiring versus the acquired organization) as employees of the lower status merger partner have different concerns than employees of the higher status merger organization. [ABSTRACT FROM AUTHOR]

Corporate mergers require proper human resources management to reach their financial and strategic objectives and minimize negative consequences for employee well-being. Understanding the antecedents of employees' identification with the merged organization during the corporate merger is crucial, because stronger post-merger identification results in less conflict and higher levels of motivation. Unfortunately, employees often identify more strongly with their pre-merger organizations than with the merged organization. One influential approach to understanding the processes underlying organizational identification is the social identity approach (; ). Research applying this perspective to organizational mergers shows that levels of identification with the merged organization are partly explained by status and dominance differences of the involved organizations, by motivational threats and uncertainties during the merger, and by the representation of the post-merger identity. Leaders and managers of corporate mergers are able to influence these processes and, thus, to provide a path for successful merger integration. [ABSTRACT FROM AUTHOR]

Many biofilm populations are known for their exceptional biodiversity, but the relative contributions of the forces that could produce this diversity are poorly understood. This uncertainty grows in the old, well-established communities found on many natural surfaces and in long-term, chronic infections. If the prevailing interactions among species within biofilms are positive, productivity should increase with diversity, but if they tend towards competition or antagonism, productivity should decrease. Here, we describe the parallel evolution of synergistic communities derived from a clone of Burkholderia cenocepacia during ∼1500 generations of biofilm selection. This long-term evolution was enabled by a new experimental method that selects for daily cycles of colonization, biofilm assembly and dispersal. Each of the six replicate biofilm populations underwent a common pattern of adaptive morphological diversification, in which three ecologically distinct morphotypes arose in the same order of succession and persisted. In two focal populations, mixed communities were more productive than any monoculture and each variant benefited from the mixture. These gains in output resulted from asymmetrical cross-feeding between ecotypes and the expansion and partitioning of biofilm space that constructed new niches. Therefore, even in the absence of starting genetic variation, prolonged selection for surface colonization generates a dynamic of ecological succession that enhances productivity. [ABSTRACT FROM AUTHOR]

We investigate the effect of long-range scalar interactions in dark matter (DM) models of cosmic structure formation with a particular focus on the formation times of haloes. Utilizing N-body simulations with 5123 DM particles we show that in our models DM haloes form substantially earlier: tracing objects up to redshift we find that the formation time, as characterized by the redshift at which the halo has assembled half of its final mass, is gradually shifted from in the fiducial Λ cold dark matter (ΛCDM) model to in the most extreme scalar-interaction model. This is accompanied by a shift of the redshift that marks the transition between merger and steady accretion epochs from in the ΛCDM haloes to in our strongest interaction model. In other words, the scalar-interacting model employed in this work produces more structures at high redshifts, prolonging at the same time the steady accretion phases. These effects taken together can help the ΛCDM model to account for a high-redshift reionization as indicated by the Wilkinson Microwave Anisotropy Probe ( WMAP) data and can alleviate issues related to the survival of the thin-disc-dominated galaxies at low redshifts. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses online educational initiatives for travel medical trainees and a residency programme that combines clinical tropical medicine and health of travellers.

We use a set of high-resolution simulations of scale-free Einstein-de Sitter cosmologies to investigate the logarithmic slope of the phase-space density profile of dark matter (DM) haloes. The initial conditions for the simulations are determined by a power-law power spectrum of the form . We compute the Q( r) profiles using the radial, tangential and full velocity dispersion, and the velocity anisotropy parameter, β( r). We express Q( r) as a single power-law and derive a median slope α in each simulation and for each definition of Q. Our main findings are: (i) the various Q( r) profiles follow a power law to a good approximation. (ii) The slopes depend on the concentration parameter c of the DM haloes, where for c≳ 10 the slopes steepen with rising concentration and for the trend flattens and even turns around. (iii) The asymptotic value of β as increases with the value of c. (iv) In accordance with Zait, Hoffman & Shlosman, becomes more negative as the asymptotic value of β at the virial radius increases. (iv) This introduces a weak dependence of the Q( r) slopes on the slope of the power spectrum. [ABSTRACT FROM AUTHOR]

Research has shown that cognitive representations of mergers influence intergroup evaluations. This paper extends this research by studying how cognitive representations of mergers (one group, dual identity, and two groups) interact with performance feedback (success and failure) to affect intergroup evaluations. Two competing hypotheses were tested, which made different predictions in case of superordinate group salience combined with subgroup salience after merger failure: The subgroup-salience-hypothesis predicts that subgroup salience during a merger generally results in pre-merger ingroup bias toward the pre-merger outgroup (i.e., two groups and dual identity). The superordinate- salience-hypothesis predicts that subgroup salience only results in pre-merger ingroup bias if superordinate group salience is low (i.e., two groups). Both hypotheses predict low levels of ingroup bias after merger success. Study 1 confirmed the second hypothesis using a 3 (merger representation: one group, dual identity, and two groups) × 2 (merger feedback: failure and success) design with interacting groups. Study 2 replicated the results in an adapted minimal group paradigm. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We explore the dependence of the central logarithmic slope of dark matter halo density profiles α on the spectral index n of the linear matter power spectrum P( k) using cosmological N-body simulations of scale-free models [i.e. P( k) ∝ k n]. These simulations are based on a set of clear, reproducible and physically motivated criteria that fix the appropriate starting and stopping times for runs, and allow one to compare haloes across models with different spectral indices and mass resolutions. For each of our simulations we identify samples of well-resolved haloes in dynamical equilibrium and we analyse their mass profiles. By parametrizing the mass profile using a ‘generalized’ Navarro, Frenk & White profile in which the central logarithmic slope α is allowed to vary while preserving the r−3 asymptotic form at large radii, we obtain preferred central slopes for haloes in each of our models. There is a strong correlation between α and n, such that α becomes shallower as n becomes steeper. However, if we normalize our mass profiles by r−2, the radius at which the logarithmic slope of the density profile is −2, we find that these differences are no longer present. This is apparent if we plot the maximum slope as a function of r/ r−2– we find that the profiles are similar for haloes forming in different n models. This reflects the importance of concentration, and reveals that the concentrations of haloes forming in steep- n cosmologies tend to be smaller than those of haloes forming in shallow- n cosmologies. We conclude that there is no evidence for convergence to a unique central asymptotic slope, at least on the scales that we can resolve. [ABSTRACT FROM AUTHOR]

Abstract: This review is an attempt to localize the brain region responsible for pattern generation of species-specific vocalizations. A catalogue is set up, listing the criteria considered to be essential for a vocal pattern generator. According to this catalogue, a vocal pattern generator should show vocalization-correlated activity, starting before vocal onset and reflecting specific acoustic features of the vocalization. Artificial activation by electrical or glutamatergic stimulation should produce artificially sounding vocalization. Lesioning is expected to have an inhibitory or deteriorating effect on vocalization. Anatomically, a vocal pattern generator can be assumed to have direct or, at least, oligosynaptic connections with all the motoneuron pools involved in phonation. A survey of the literature reveals that the only area meeting all these criteria is a region, reaching from the parvocellular pontine reticular formation just above the superior olive through the lateral reticular formation around the facial nucleus and nucleus ambiguus down to the caudalmost medulla, including the dorsal and ventral reticular nuclei and nucleus retroambiguus. It is proposed that vocal pattern generation takes place within this whole region. [Copyright &y& Elsevier]

In a recent study, we localized a discrete area in the ventrolateral pontine brainstem of squirrel monkeys, which seems to play a role in vocal pattern generation of frequency-modulated vocalizations. The present study compares the neuronal activity of this area with that of three motoneuron pools involved in phonation, namely the trigeminal motor nucleus, facial nucleus, and nucleus ambiguus. The experiments were performed in freely moving squirrel monkeys (Saimiri sciureus) during spontaneous vocal communication, using a telemetric single-unit recording technique. We found vocalization-related activity in all motoneuron pools recorded. Each of them, however, showed a specific profile of activity properties with respect to call types uttered, syllable structure, and pre-onset time. Different activity profiles were also found for neurons showing purely vocalization-correlated activity, vocalization- and mastication-correlated activity, and vocalization- and respiration-correlated activity. By comparing the activity properties of the proposed vocal pattern generator with the three motoneuron pools, we show that the pontine vocalization area is, in fact, able to control each of the three motoneuron pools during frequency-modulated vocalizations. The present study thus supports the existence of a vocal pattern generator for frequency-modulated call types in the ventrolateral pontine brainstem. [ABSTRACT FROM AUTHOR]

The adjustment of the voice by auditory input happens at several brain levels. The caudal pontine brainstem, though rarely investigated, is one candidate area for such audio–vocal integration. We recorded neuronal activity in this area in awake, behaving squirrel monkeys ( Saimiri sciureus) during vocal communication, using telemetric single-unit recording techniques. We found audio–vocal neurons at locations not described before, namely in the periolivary region of the superior olivary complex and the adjacent pontine reticular formation. They showed various responses to external sounds (noise bursts) and activity increases (excitation) or decreases (inhibition) to self-produced vocalizations, starting prior to vocal onset and continuing through vocalizations. In most of them, the responses to noise bursts and self-produced vocalizations were similar, with the only difference that neuronal activity started prior to vocal onset. About one-third responded phasically to noise bursts, independent of whether they increased or decreased their activity to vocalization. The activity of most audio–vocal neurons correlated with basic acoustic features of the vocalization, such as call duration and/or syllable structure. Auditory neurons near audio–vocal neurons showed significantly more frequent phasic response patterns than those in areas without audio–vocal activity. Based on these findings, we propose that audio–vocal neurons showing similar activity to external acoustical stimuli and vocalization play a role in olivocochlear regulation. Specifically, audio–vocal neurons with a phasic response to external auditory stimuli are candidates for the mediation of basal audio–vocal reflexes such as the Lombard reflex. Thus, our findings suggest that complex audio–vocal integration mechanisms exist in the ventrolateral pontine brainstem. [ABSTRACT FROM AUTHOR]

Abstract: A telemetric system is described which allows the wireless registration of extracellular neuronal activity and vocalization-associated skull vibrations in freely moving, socially living squirrel monkeys (Saimiri sciureus). The system consists of a carrier platform with numerous guiding tubes implanted on the skull. Custom-made microdrives are mounted on the platform, allowing the exploration of two electrode tracks at the same time. Commercially available quartz-insulated platinum–tungsten microelectrodes are used. The electrodes can be moved over a distance of 8–10mm by turning a screw on the microdrive. Vocalization-associated skull vibrations are recorded with a piezo-ceramic element. Skull vibration signal and the signals from the two microelectrodes are fed into separate transmitters having different carrier frequencies. The signals are picked up by an antenna in the animal cage and are sent to three receivers in the central laboratory. Here, the signals are transferred via an analog/digital interface to a personal computer for data analysis and to a video recorder for long-term storage. The total weight of the head mount including carrier platform, microdrive, electrodes, skull vibration sensor, three transmitters, and protection cap is 32g. The transmitters are powered with two rechargeable lithium batteries, allowing about 8h of continuous recording. Reliable signal transmission is obtained over a distance of about 2m. Recording stability allows to follow the activity of specific neurons up to several hours, with no movement artefacts during locomotion. [Copyright &y& Elsevier]

Very little is known about the coordination of muscles involved in mammalian vocalization at the level of single neurons. In the present study, a telemetric single-unit recording technique was used to explore the ventrolateral pontine brainstem for vocalization-correlated activity in the squirrel monkey during vocal communication. We found a discrete area in the reticular formation just above the superior olivary complex showing vocalization-correlated activity. These neurons showed an increase in neuronal activity exclusively just before and during vocalization; none of them was active during mastication, swallowing or quiet respiration. Furthermore, the neuronal activity of these neurons reflected acoustic features, such as call duration or syllable structure of frequency-modulated vocalization, directly. Based on these findings and previously reported anatomical data, we propose that this area serves as a vocal pattern generator for frequency-modulated call types. [ABSTRACT FROM AUTHOR]

Background: Recent epidemiologic data on travelers' diarrhea (TD) are essential for the evaluation of conventional and future prophylactic and therapeutic measures.Methods: To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.Results: Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.Conclusions: TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve. [ABSTRACT FROM AUTHOR]

In auditory maps of the primary auditory cortex, neural response properties are arranged in a systematic way over the cortical surface. As in the visual system, such maps may play a critical role in the representation of sounds for perception and cognition. By recording from single neurons in the central nucleus of the inferior colliculus (ICC) of the mouse, we present the first evidence for spatial organizations of parameters of frequency sweeps (sweep speed, upward/downward sweep direction) and of whole-field tone response patterns together with a map of frequency tuning curve shape. The maps of sweep speed, tone response patterns and tuning curve shape are concentrically arranged on frequency band laminae of the ICC with the representation of slow speeds, build up response types and sharp tuning mainly in the centre of a lamina, and all (including high) speeds, phasic response types and broad tuning mainly in the periphery. Representation of sweep direction shows preferences for upward sweeps medially and laterally and downward sweeps mainly centrally in the ICC (either striped or concentric map). These maps are compatible with the idea of a gradient of decreasing inhibition from the centre to the periphery of the ICC and by gradients of intrinsic neuronal properties (onset or sustained responding). The maps in the inferior colliculus compare favourably with corresponding maps in the primary auditory cortex, and we show how the maps of sweep speed and direction selectivity of the primary auditory cortex could be derived from the here-found maps of the inferior colliculus. [ABSTRACT FROM AUTHOR]