Fast and Efficient Image Novelty Detection Based on Mean-Shifts.

Image novelty detection is a repeating task in computer vision and describes the detection of anomalous images based on a training dataset consisting solely of normal reference data. It has been found that, in particular, neural networks are well-suited for the task. Our approach first transforms the training and test images into ensembles of patches, which enables the assessment of mean-shifts between normal data and outliers. As mean-shifts are only detectable when the outlier ensemble and inlier distribution are spatially separate from each other, a rich feature space, such as a pre-trained neural network, needs to be chosen to represent the extracted patches. For mean-shift estimation, the Hotelling T2 test is used. The size of the patches turned out to be a crucial hyperparameter that needs additional domain knowledge about the spatial size of the expected anomalies (local vs. global). This also affects model selection and the chosen feature space, as commonly used Convolutional Neural Networks or Vision Image Transformers have very different receptive field sizes. To showcase the state-of-the-art capabilities of our approach, we compare results with classical and deep learning methods on the popular dataset CIFAR-10, and demonstrate its real-world applicability in a large-scale industrial inspection scenario using the MVTec dataset. Because of the inexpensive design, our method can be implemented by a single additional 2D-convolution and pooling layer and allows particularly fast prediction times while being very data-efficient.

Efficient antisense inhibition reveals microRNA-155 to restrain a late-myeloid inflammatory programme in primary human phagocytes.

A persisting obstacle in human immunology is that blood-derived leukocytes are notoriously difficult to manipulate at the RNA level. Therefore, our knowledge about immune-regulatory RNA-networks is largely based on tumour cell-line and rodent knockout models, which do not fully mimic human leukocyte biology. Here, we exploit straightforward cell penetrating peptide (CPP) chemistry to enable efficient loss-of-function phenotyping of regulatory RNAs in primary human blood-derived cells. The classical CPP octaarginine (R8) enabled antisense peptide-nucleic-acid (PNA) oligomer delivery into nearly 100% of human blood-derived macrophages without apparent cytotoxicity even up to micromolar concentrations. In a proof-of-principle experiment, we successfully de-repressed the global microRNA-155 regulome in primary human macrophages using a PNA-R8 oligomer, which phenocopies a CRISPR-Cas9 induced gene knockout. Interestingly, although it is often believed that fairly high concentrations (µM) are needed to achieve antisense activity, our PNA-R8 was effective at 200 nM. RNA-seq characterized microRNA-155 as a broad-acting riboregulator, feedback restraining a late myeloid differentiation-induced pro-inflammatory network, comprising MyD88-signalling and ubiquitin-proteasome components. Our results highlight the important role of the microRNA machinery in fine-control of blood-derived human phagocyte immunity and open the door for further studies on regulatory RNAs in difficult-to-transfect primary human immune cells.

[Long-Term Patterns of Depressive Symptomload and their Predictors in Hospitalised Patients Undergoing Psychodynamic Psychotherapy: Findings of the STOP-D Study]. / Langzeitverläufe depressiver Symptomlast und deren Prädiktoren bei stationärer, tiefenpsychologisch fundierter Psychotherapie: Befunde der STOP-D-Studie.

OBJECTIVE: Depression is one of the most common mental disorders. While the general effectiveness of in- and outpatient psychotherapy is proven, different long-term patterns in treatment of symptoms of depression have been described. The aim of the present study was to show different patterns of benefit in the context of inpatient psychodynamic psychotherapy of depressive disorders and to detect predictors of different types of response that help to identify possible non-responders and adjust treatments accordingly. METHODS: Data of the naturalistic multicentre intervention study were collected in 15 German psychosomatic hospital units employing a predominantly psychodynamic approach to treatment. The sample includes n=432 patients (women: age 25-45 years) with typical symptoms of depression. The patterns of outcome were identified using a latent state model with a method factor and a latent class analysis; potential course predictors were analysed using regression analysis. RESULTS: Three long-term patterns of outcome were identified: patients with significant treatment benefit, whose symptom decline was stable even in a 6-month catamnesis (Responders: 76.9%), patients without a significant symptom decrease during treatment and in the follow-up survey (Non-responders: 18.8%), as well as patients with a significant symptom decrease but showing an increase of symptoms in the catamnesis (Backsliders: 4.4%). The severity of baseline depressive symptom load was determined as a predictor for the pattern of Backsliders. Non-responders differed from responders in having had psychosomatic pre-treatments more frequently. DISCUSSION: In the case of backsliders, further studies should, for instance, verify whether relapses can be explained by the patient's symptoms, treatment, or social environment. In the case of non-response due to numerous unsuccessful pre-treatments, the question arises whether psychosomatic treatment offers the right setting for these patients or how therapy settings should be modified. CONCLUSION: Long-term patterns reported in the literature were partially confirmed. There are indications of an influence of the initial symptom-load severity on the outcome of treatment. It is important to consider how treatment settings can be modified accordingly.

[Sleep disorders reduce the therapeutic success of inpatient psychosomatic treatments for depressive disorders]. / Schlafstörungen verringern den Therapieerfolg stationärer psychosomatischer Behandlungen bei depressiven Störungen.

Sleep disorders reduce the therapeutic success of inpatient psychosomatic treatments for depressive disorders Objective: What influence do difficulties in falling and staying asleep in patients with depressive disorders have on the success of psychosomatic treatment? Method: The Data were collected in a naturalistic, multicenter observational study (STOP-D) at the beginning (T1), the end (T2) and six months later after discharge (T3). The sample consisted of female patients with depressive disorders (N = 487) who were treated for M = 61.7 days (SD = 26.8). An insomnia scale with a total of seven items was created subsequently to T1 from Items of the Beck Depression Inventory (BDI-I), from the Hamilton Depression Scale (HAMD) and from the Global Severe Index (GSI) from the Symptom Checklist 90 (SCL-90-R). Then groups were formed on changes in insomnia symptoms from T1 to T2. These two groups "sleep improver" and "sleep deteriorators" were tested by analysis of variance. Results: The subsequently constructed insomnia scale showed good psychometric characteristics in the performed analyses. Patients who reported an improvement in their sleep disturbances during inpatient psychosomatic treatment had significantly lower depression scores in the self-evaluation inventories (BDI-I und SCL-90-R) than patients without improvements in their sleep patterns. This effect was even more pronounced for the catamnestic period. Discussion: Insomnia symptoms in depressed female patients can be an important indicator of the effect of inpatient psychosomatic treatment and can have negative impact on the sustainability of the therapy success.

Patient quality of life after vestibular schwannoma removal: possibilities and limits to measuring different domains of patients' wellbeing.

PURPOSE: Since the 1980s, health-related quality of life (HRQOL) has been recognized in the assessment of medical treatment. To determine the health-related quality of life (HRQOL) of vestibular schwannoma (VS) patients, a specific questionnaire that has been validated in different languages is essential. METHODS: The Short Form-36 Health Survey (SF-36) and PANQOL questionnaires in German were evaluated in patients after removal of a VS via the translabyrinthine approach. Descriptive statistics of a comparison of the SF-36 results to those of a normal sample are illustrated. Criterion validity was investigated using Spearman's rank test to correlate the PANQOL domains with the SF-36 domains. A confirmatory factor analysis of the PANQOL was performed to determine the stability of the factor structure of the PANQOL questionnaire for our cohort. RESULTS: The criterion validity of the German PANQOL questionnaire is comparable to that of the original English version. The SF-36 domains values ranged from 49.31/100 (role physical) to 66.46/100 (physical functioning). Compared to the normal population, patients who underwent surgical removal of a VS showed a significantly reduced quality of life, mainly in domains such as physical and social functioning, as well as psychological wellbeing. CONCLUSION: The German PANQOL has been validated and is now available. Post-surgical treatment should be focused not only on physiological rehabilitation but also on improving the quality of life, especially aspects of psychological and social wellbeing.

[Long-term effectiveness of psychodynamic inpatient therapy on depressive disorders - Catamnestic- Results of the STOP-D-Study]. / Langzeiteffekte tiefenpsychologisch fundierter stationärer Psychotherapie bei Depressionen ­ Katamnesebefunde der STOP-D-Studie.

Long-term effectiveness of psychodynamic inpatient therapy on depressive disorders - Catamnestic- Results of the STOP-D-Study Objectives: Depression is one of the most common disorders with a rate of recurrence between 60-75 %. The effectiveness of psychodynamic therapy is well-proven, but there is still a lack of studies proving the long-term effectiveness of inpatient treatment on depressive symptom load. Methods: After psychodynamic inpatient treatment in a psychodynamically oriented psychosomatic hospital unit, the reduction in general and depressive symptom load (e. g. BDI, HAMD, SCL-90-R) was evaluated by a six-month follow up design. The study was set up as naturalistic multicenter intervention study including a female follow-up sample (N = 291; age 25-45 years). Results: The symptom improvement reached by the inpatient treatment remained stable at the follow-up survey. Patients treated with antidepressant medication showed stronger depressive symptom load at discharge and follow-up survey compared to patients without antidepressant medication. Sociodemographic variables and a comorbid personality disorder were not associated with increased drop-out rates, but depressive symptom load and a premature ending of the treatment. Conclusions: The obtained results demonstrate the long-term effectiveness of inpatient psychodynamic psychotherapy. Further studies about the influence of post-hospital psychotherapy and medical treatment as well as patient satisfaction seem necessary.

[Depression and Comorbid Personality Disorder - Effectiveness of Psychodynamic Inpatient Psychotherapy]. / Depression und komorbide Persönlichkeitsstörung ­ Effekte stationärer tiefenpsychologisch fundierter Psychotherapie.

Objectives Depression is one of the most common illnesses. The effectiveness of psychodynamic psychotherapy on depressive symptom load has been demonstrated. However, for patients suffering from comorbid personality disorder (PD) a decreased benefit has been reported, as well as fewer rates of remission and extended duration of remission. However, findings are inconsistent. The objective of this study was to determine potential differences in therapy-outcome comparing female patients with and without comorbid PD. Method Including female inpatients aged between 25-45 years (N=377) in a psychodynamic treatment, the dissenting outcome on depressive symptom load (among others BDI; HAMD) as well as psychodynamic variables (IPO) by patients with and without comorbid PD were analysed within a naturalistic multicenter intervention study (STOP-D). Data were collected in 15 psychodynamically oriented psychosomatic hospital units in Germany, based on self- and external-assessment instruments. Results Under comparable therapy-doses, female patients with and without comorbid PD benefit significantly from psychodynamic inpatient treatment. By equivalent baseline severity of clinical symptoms patients without comorbid PD show larger effect sizes in all inventories than patients with comorbid PD. Discussion Although the benefit is lower for depressed patients with comorbid personality disorder, the positive effect of inpatient psychodynamic psychotherapy is statistically and clinically significant in both groups. Influences of further comorbid symptoms and confounding symptoms between depression and PD, which were difficult to control, are possible. Further studies are necessary. Conclusion Although patients with comorbid PD benefit significantly from the inpatient treatment, a special therapeutic design seems to be indicated for these patients.

[Health-related long-term effects of adverse childhood experiences - an update]. / Gesundheitliche Langzeitfolgen psychosozialer Belastungen in der Kindheit - ein Update.

In the last decade strong empirical evidence from several long-term studies supports the conclusion that physical and sexual abuse as well as emotional deprivation in childhood make people significantly more vulnerable to mental and functional disorders across their lifetime. Additionally, an increased vulnerability to several somatic disorders (cardiovascular disorders, type-2-diabetes, hepatitis, chronic obstructive pulmonary disease (COPD), immunological and pain disorders, pharynx and lung cancer) was demonstrated - most of them with a reduced life expectancy. A review of the current research will be presented that outlines the underlying developmental neurobiological and psychological mechanisms mediating these long-term effects. There is now sufficient evidence about familial risk constellations that demonstrates the well-documented impact of specific prevention strategies by several model projects. Only by establishing these strategies, future enormous health-related burdens and high economic costs (unfitness to work, early retirement) can presumably be limited.

[Psychodynamically oriented inpatient psychotherapy of depressive disorders - First findings from a naturalistic, multicenter study]. / Stationäre tiefenpsychologisch orientierte Psychotherapie bei depressiven Störungen (STOP-D) - Erste Befunde einer naturalistischen, multizentrischen Wirksamkeitsstudie.

OBJECTIVES: While the general effectiveness of psychodynamic psychotherapy in both outpatient and inpatient treatment has been proven, few studies document the effectiveness of clinical inpatient treatment of depression through psychodynamic psychotherapy. METHODS: This paper presents first results of a naturalistic multicenter intervention study. Included were female inpatients suffering from depressive symptoms who had been admitted to 15 psychodynamically oriented psychosomatic hospital units (N = 487). The mean duration of treatment was 61.8 days. Data were acquired at admission (T1) and discharge (T2). RESULTS: Our findings support previous evidence and show that psychodynamically oriented inpatient psychotherapy of depressive disorders is efficient. High pre-post effect sizes were documented in all psychometric instruments used (BDI, HAM-D, SCL-90-R, BSS, GAF). Initial subgroup comparisons reveal that the benefits for patients with comorbid personality disorder are significantly lower than for depressed patients without comorbid personality disorder. CONCLUSION: Psychodynamic inpatient psychotherapy, as practiced under naturalistic conditions, is an effective treatment of depression. Predictors of therapeutic effects within different therapeutic settings, however, remain unclear. The sustainability of the therapeutic effects found and their impact on psychodynamic relevant constructs have still to be proven.

Measuring facial mimicry: Affdex vs. EMG.

Facial mimicry is the automatic imitation of the facial affect expressions of others. It serves as an important component of interpersonal communication and affective co-experience. Facial mimicry has so far been measured by Electromyography (EMG), which requires a complex measuring apparatus. Recently, software for measuring facial expressions have become available, but it is still unclear how well it is suited for measuring facial mimicry. This study investigates the comparability of the automated facial coding software Affdex with EMG for measuring facial mimicry. For this purpose, facial mimicry was induced in 33 subjects by presenting naturalistic affect-expressive video sequences (anger, joy). The response of the subjects is measured simultaneously by facial EMG (corrugator supercilii muscle, zygomaticus major muscle) and by Affdex (action units lip corner puller and brow lowerer and affects joy and anger). Subsequently, the correlations between the measurement results of EMG and Affdex were calculated. After the presentation of the joy stimulus, there was an increase in zygomaticus muscle activity (EMG) about 400 ms after stimulus onset and an increase in joy and lip corner puller activity (Affdex) about 1200 ms after stimulus onset. The joy and the lip corner puller activity detected by Affdex correlate significantly with the EMG activity. After presentation of the anger stimulus, corrugator muscle activity (EMG) also increased approximately 400 ms after stimulus onset, whereas anger and brow lowerer activity (Affdex) showed no response. During the entire measurement interval, anger activity and brow lowerer activity (Affdex) did not correlate with corrugator muscle activity (EMG). Using Affdex, the facial mimicry response to a joy stimulus can be measured, but it is detected approximately 800 ms later compared to the EMG. Thus, electromyography remains the tool of choice for studying subtle mimic processes like facial mimicry.

The influence of patient-centered teaching on medical students' stigmatization of the mentally ill.

Aim: Stigmatization by healthcare workers poses a challenge to providing care to the mentally ill. Bedside teaching during undergraduate medical education offers students an opportunity to directly interact with patients with a range of psychiatric disorders and thereby gather reflective experience. The present study investigates if this supervised contact with mentally ill patients during a one-week clinical course on psychosomatic medicine leads to stigma reduction in medical students. The factors influencing stigmatization were also investigated. Method: This was a prospective, non-randomized, controlled interventional study done in the 2019/20 winter semester involving fourth-year medical students who attended a week-long practical block on psychosomatic medicine (intervention group). This group was compared to students who had attended a week-long practical block with a somatic focus during the same time period (control group). Stigmatization was measured before and immediately upon completion of the week using the MICA-4 scale. Data on age, sex, experience with the mentally ill, interest in psychiatry/psychosomatics, and sense of self-worth were also gathered prior to starting the practical block. Analysis of the sample of 143 students with a complete basic data set was carried out using mixed ANOVA, multiple linear regression and moderator analysis. Results: In the context of clinical teaching with psychiatric patients, the stigmatization of the mentally ill among medical students decreased significantly more in the intervention group compared to the students in the control group who received instruction on somatic topics (p=.019, η2p=.04). In addition, being female, having previous experience with the mentally ill and general interest in the subjects of psychiatry or psychosomatics at T0 associated with lower stigma. In contrast, stigmatization was increased at the beginning of the study in males and those with low self-esteem. A moderating effect of the factors on stigma reduction was not seen. Conclusion: Undergraduate clinical instruction that enables direct contact and reflective experiences with the mentally ill leads to a reduction in the stigmatizing attitudes held by medical students toward the mentally ill. This underscores the need to have practical clinical instruction using patients.

Complex echo classification by echo-locating bats: a review.

Echo-locating bats constantly emit ultrasonic pulses and analyze the returning echoes to detect, localize, and classify objects in their surroundings. Echo classification is essential for bats' everyday life; for instance, it enables bats to use acoustical landmarks for navigation and to recognize food sources from other objects. Most of the research of echo based object classification in echo-locating bats was done in the context of simple artificial objects. These objects might represent prey, flower, or fruit and are characterized by simple echoes with a single up to several reflectors. Bats, however, must also be able to use echoes that return from complex structures such as plants or other types of background. Such echoes are characterized by superpositions of many reflections that can only be described using a stochastic statistical approach. Scientists have only lately started to address the issue of complex echo classification by echo-locating bats. Some behavioral evidence showing that bats can classify complex echoes has been accumulated and several hypotheses have been suggested as to how they do so. Here, we present a first review of this data. We raise some hypotheses regarding possible interpretations of the data and point out necessary future directions that should be pursued.

The effect of a lightweight massage system in a car seat on comfort and electromyogram.

OBJECTIVE: The objective of this study was to determine the effect of a lightweight low-intensity massage system (LWMAS) in a car seat on the electromyogram (EMG) of the neck and shoulder muscles and on the comfort experience during driving. METHODS: Two experiments were performed during driving with and without the active LWMAS in the seat. Subjective measurements were taken, in which the comfort experience was recorded for 20 participants driving a prescribed path around Munich for 120 minutes. Then objective (surface EMG above the rhomboideus and trapezius muscles) measurements and subjective measurements of the comfort experience were recorded over 7 laps on a test track for 24 participants. RESULTS: The comfort was higher, and the EMG was significantly lower in the trapezius area while driving with the LWMAS. CONCLUSION: Despite the fact that the LWMAS system is lightweight, has low intensity, and might have had a smaller effect, similar effects to previous studies with heavier systems were found, indicating that this massage system increases comfort and reduces muscle activity during driving as well.

Alexithymia and Facial Mimicry in Response to Infant and Adult Affect-Expressive Faces.

Facial mimicry is the automatic tendency to imitate facial expressions of emotions. Alexithymia is associated with a reduced facial mimicry ability to affect expressions of adults. There is evidence that the baby schema may influence this process. In this study it was tested experimentally whether facial mimicry of the alexithymic group (AG) is different from the control group (CG) in response to dynamic facial affect expressions of children and adults. A multi-method approach (20-point Toronto Alexithymia Scale and Toronto Structured Interview for Alexithymia) was used for assessing levels of alexithymia. From 3503 initial data sets, two groups of 38 high and low alexithymic individuals without relevant mental or physical diseases were matched regarding age, gender, and education. Facial mimicry was induced by presentation of naturalistic affect-expressive video sequences (fear, sadness, disgust, anger, and joy) taken from validated sets of faces from adults (Averaged Karolinska Directed Emotional Faces) and children (Picture-Set of Young Children's Affective Facial Expressions). The videos started with a neutral face and reached maximum affect expression within 2 s. The responses of the groups were measured by facial electromyographic activity (fEMG) of corrugator supercilii and zygomaticus major muscles. Differences in fEMG response (4000 ms) were tested in a variance analytical model. There was one significant main effect for the factor emotion and four interaction effects for the factors group × age, muscle × age, muscle × emotion, and for the triple interaction muscle × age × emotion. The participants of AG showed a decreased fEMG activity in response to the presented faces of adults compared to the CG but not for the faces of children. The affect-expressive faces of children induced enhanced zygomatic and reduced corrugator muscle activity in both groups. Despite existing deficits in the facial mimicry of alexithymic persons, affect-expressive faces of children seem to trigger a stronger positive emotional involvement even in the AG.

It is in your face-Alexithymia impairs facial mimicry.

Alexithymia is characterized by a reduced ability to identify and differentiate emotional aspects of social interaction. In this study we investigated, for the first time, whether alexithymia impairs facial mimicry in response to dynamic naturalistic facial affect expressions. Potential volunteers were recruited by means of an online survey (N = 3503). Based on their Toronto Alexithymia Scale-20 sum-score (TAS-20) probands were assigned to an alexithymic group (AG; M = 58.11, SD = 4.58) or a nonalexithymic healthy control group (HC; M = 32.05, SD = 5.56). Both groups were matched by age, gender, and education. All probands were shown digitally generated naturalistic video sequences of faces displaying the basic affects of fear, sadness, disgust, anger, and joy. During the presentation, the participants' facial mimicry responses were recorded by registering the electromyographic (EMG) activity of the corrugator supercilii and zygomaticus major muscles. Overall, the alexithymic probands showed a significantly lower facial EMG activity in response to the affective faces compared to HC. The results thus suggest that alexithymia is associated with a reduced facial mimicry. We discuss the implications of these findings from the perspective of alexithymic impairments within social interaction and the consideration for psychotherapeutic treatment. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Creation and validation of the Picture-Set of Young Children's Affective Facial Expressions (PSYCAFE).

The immediate detection and correct processing of affective facial expressions are one of the most important competences in social interaction and thus a main subject in emotion and affect research. Generally, studies in these research domains, use pictures of adults who display affective facial expressions as experimental stimuli. However, for studies investigating developmental psychology and attachment behaviour it is necessary to use age-matched stimuli, where it is children that display affective expressions. PSYCAFE represents a newly developed picture-set of children's faces. It includes reference portraits of girls and boys aged 4 to 6 years averaged digitally from different individual pictures, that were categorized to six basic affects (fear, disgust, happiness, sadness, anger and surprise) plus a neutral facial expression by cluster analysis. This procedure led to deindividualized and affect prototypical portraits. Individual affect expressive portraits of adults from an already validated picture-set (KDEF) were used in a similar way to create affect prototypical images also of adults. The stimulus set has been validated on human observers and entail emotion recognition accuracy rates and scores for intensity, authenticity and likeability ratings of the specific affect displayed. Moreover, the stimuli have also been characterized by the iMotions Facial Expression Analysis Module, providing additional data on probability values representing the likelihood that the stimuli depict the expected affect. Finally, the validation data from human observers and iMotions are compared to data on facial mimicry of healthy adults in response to these portraits, measured by facial EMG (m. zygomaticus major and m. corrugator supercilii).

Early identification of postpartum depression using demographic, clinical, and digital phenotyping.

Postpartum depression (PPD) and adjustment disorder (AD) affect up to 25% of women after childbirth. However, there are no accurate screening tools for either disorder to identify at-risk mothers and enable them to benefit from early intervention. Combinations of anamnestic, clinical, and remote assessments were evaluated for an early and accurate identification of PPD and AD. Two cohorts of mothers giving birth were included in the study (N = 308 and N = 193). At baseline, participants underwent a detailed sociodemographic-anamnestic and clinical interview. Remote assessments were collected over 12 weeks comprising mood and stress levels as well as depression and attachment scores. At 12 weeks postpartum, an experienced clinician assigned the participants to three distinct groups: women with PPD, women with AD, and healthy controls (HC). Combinations of these assessments were assessed for an early an accurate detection of PPD and AD in the first cohort and, after pre-registration, validated in a prospective second cohort. Combinations of postnatal depression, attachment (for AD) and mood scores at week 3 achieved balanced accuracies of 93 and 79% for differentiation of PPD and AD from HC in the validation cohort and balanced accuracies of 87 and 91% in the first cohort. Differentiation between AD and PPD, with a balanced accuracy of 73% was possible at week 6 based on mood levels only with a balanced accuracy of 73% in the validation cohort and a balanced accuracy of 76% in the first cohort. Combinations of in clinic and remote self-assessments allow for early and accurate detection of PPD and AD as early as three weeks postpartum, enabling early intervention to the benefit of both mothers and children.

Sequence-Selective Covalent CaaX-Box Receptors Prevent Farnesylation of Oncogenic Ras Proteins and Impact MAPK/PI3†K Signaling.

Oncogenic Ras proteins are implicated in the most common life-threatening cancers. Despite intense research over the past two decades, the progress towards small-molecule inhibitors has been limited. One reason for this failure is that Ras proteins interact with their effectors only via protein-protein interactions, which are notoriously difficult to address with small organic molecules. Herein we describe an alternative strategy, which prevents farnesylation and subsequent membrane insertion, a prerequisite for the activation of Ras proteins. Our approach is based on sequence-selective supramolecular receptors which bind to the C-terminal farnesyl transferase recognition unit of Ras and Rheb proteins and covalently modify the essential cysteine in the so-called CaaX-box.

The voice of bats: how greater mouse-eared bats recognize individuals based on their echolocation calls.

Echolocating bats use the echoes from their echolocation calls to perceive their surroundings. The ability to use these continuously emitted calls, whose main function is not communication, for recognition of individual conspecifics might facilitate many of the social behaviours observed in bats. Several studies of individual-specific information in echolocation calls found some evidence for its existence but did not quantify or explain it. We used a direct paradigm to show that greater mouse-eared bats (Myotis myotis) can easily discriminate between individuals based on their echolocation calls and that they can generalize their knowledge to discriminate new individuals that they were not trained to recognize. We conclude that, despite their high variability, broadband bat-echolocation calls contain individual-specific information that is sufficient for recognition. An analysis of the call spectra showed that formant-related features are suitable cues for individual recognition. As a model for the bat's decision strategy, we trained nonlinear statistical classifiers to reproduce the behaviour of the bats, namely to repeat correct and incorrect decisions of the bats. The comparison of the bats with the model strongly implies that the bats are using a prototype classification approach: they learn the average call characteristics of individuals and use them as a reference for classification.