The influence of time headway on subjective driver states in adaptive cruise control

There is no agreement on the relation between driving parameters and drivers’ subjective states. A linear as well as a threshold relationship for different subjective variables and driving parameters has been put forward. In this study we investigate the relationship between time headway and the ratings of risk, task difficulty, effort, and comfort. Knowledge about this interrelation may advance the development of adaptive cruise control and autonomous driving and can add to the discussion about driver behavior models. An earlier study (Lewis-Evans, De Waard, & Brookhuis, 2010) found a threshold effect for drivers’ ratings of subjective variables for time headways between 0.5 and 4.0 s at a speed of 50 km/h. This study aims to replicate the threshold effect and to expand the findings to time headways at different speeds. A new measure for criticality was added as a categorical variable, indicating the controllability of a driving situation to give indications for the appliance of time headway in adaptive cruise control systems. Participants drove 24 short routes in a driving simulator with predefined speed and time headway to a leading vehicle. Time headway was varied eightfold (0.5–4 s in 0.5 s increments) and speed was varied threefold (50, 100, 150 km/h). A threshold effect for the ratings of risk, task difficulty, effort, and comfort was found for all three different speeds. Criticality proved to be a useful variable in assessing the preferred time headway of drivers

The exact determination of subjective risk and comfort thresholds in car following

In this study the location of vehicle to vehicle distance thresholds for self-reported subjective risk and comfort was researched. Participants were presented with ascending and descending time headway sequences in a driving simulator. This so called method of limits of ascending and descending stimuli (Gouy, Diels, Reed, Stevens, & Burnett, 2012) was refined to efficiently determine individual thresholds for stable time headways with a granularity of 0.1 seconds. Time headway thresholds were researched for 50, 100, and 150 km/h in a city, rural, and highway setting. Furthermore, thresholds for self-driving (level 0 automation: NHTSA, 2013) were compared with thresholds for the experience of subjective risk and comfort in assisted driving, similar to adaptive cruise control (level 1 automation). Results show that preferred individual time headways vary between subjects. Within subjects however, time headway thresholds do not significantly differ for different speeds. Furthermore we found that there was no significant difference between time headways of self-driving and distance-assisted driving. The relevance of these findings for the development of adaptive cruise control systems, autonomous driving and driver behavior modelling is discussed

Characteristics of clinical-pharmacological recommendations in psychiatry.

OBJECTIVE Psychiatric patients in general, and elderly psychiatric patients in particular, are at risk of adverse drug reactions due to comorbidities and inappropriate polypharmacy. Interdisciplinary and clinical-pharmacologist-led medication reviews may contribute to medication safety in the field of psychiatry. In this study, we reported the frequency and characteristics of clinical-pharmacological recommendations in psychiatry, with a particular focus on geriatric psychiatry. METHOD A clinical pharmacologist, in collaboration with the attending psychiatrists and a consulting neurologist, conducted interdisciplinary medication reviews in a general psychiatric ward with a geropsychiatric focus at a university hospital over a 25-week period. All clinical and pharmacological recommendations were recorded and evaluated. RESULTS A total of 316 recommendations were made during 374 medication reviews. Indications/contraindications of drugs were the most frequently discussed topics (59/316; 18.7 %), followed by dose reductions (37/316; 11.7 %), and temporary or permanent discontinuation of medications (36/316; 11.4 %). The most frequent recommendations for dose reduction involvedbenzodiazepines (9/37; 24.3 %). An unclear or absent indication was the most common reason for recommending temporary or permanent discontinuation of the medication (6/36; 16.7 %). CONCLUSION Interdisciplinary clinical pharmacologist-led medication reviews represented a valuable contribution to medication management in psychiatric patients, particularly the elderly ones

Effects of temporal floral resource availability and non-crop habitats on broad bean pollination

Context Flowering plants can enhance wild insect populations and their pollination services to crops in agricultural landscapes, especially when they flower before the focal crop. However, characterizing the temporal availability of specific floral resources is a challenge. Objectives Developing an index for the availability of floral resources at the landscape scale according to the specific use by a pollinator. Investigating whether detailed and temporally-resolved floral resource maps predict pollination success of broad bean better than land cover maps. Methods We mapped plant species used as pollen source by bumblebees in 24 agricultural landscapes and developed an index of floral resource availability for different times of the flowering season. To measure pollination success, patches of broad bean (Vicia faba), a plant typically pollinated by bumblebees, were exposed in the center of selected landscapes. Results Higher floral resource availability before bean flowering led to enhanced seed set. Floral resource availability synchronous to broad bean flowering had no effect. Seed set was somewhat better explained by land cover maps than by floral resource availability, increasing with urban area and declining with the cover of arable land. Conclusions The timing of alternative floral resource availability is important for crop pollination. The higher explanation of pollination success by land cover maps than by floral resource availability indicates that additional factors such as habitat disturbance and nesting sites play a role in pollination. Enhancing non-crop woody plants in agricultural landscapes as pollen sources may ensure higher levels of crop pollination by wild pollinators such as bumblebees

Long-term patency of arteriovenous fistulas for hemodialysis: A decade's experience in a transplant unit

BACKGROUND The heterogeneous quality of studies on arteriovenous fistulas outcome, with variable clinical settings and large variations in definitions of patency and failure rates, leads to frequent misinterpretations and overestimation of arteriovenous fistula patency. Hence, this study aimed to provide realistic and clinically relevant long-term arteriovenous fistula outcomes. METHODS We retrospectively analyzed all autologous arteriovenous fistulas at our center over a 10-year period (2012-2022). Primary and secondary patency analysis was conducted using the Kaplan-Meier method; multivariate analysis of variance was used to detect outcome predictors. Vascular access-specific endpoints were defined according to the European guidelines on vascular access formation. FINDINGS Of 312 arteriovenous fistulas, 57.5% (n = 181) were radio-cephalic (RC_AVF), 35.2% (n = 111) brachio-cephalic (BC_AVF), and 6.3% (n = 20) brachio-basilic (BB_AVF). 6, 12, and 24 months follow-up was available in 290 (92.1%), 282 (89.5%), and 259 (82.2%) patients, respectively. Primary patency rates at 6, 12, and 24 months were 39.5%, 34.8%, and 27.2% for RC_AVF, 58.3%, 44.4%, and 27.8% for BC_AVF, and 40.0%, 42.1%, and 22.2% for BB_AVF (p = 0.15). Secondary patency rates at 6, 12, and 24 months were 65.7%, 63.8%, and 59.0% for RC_AVF, 77.7%, 72.0%, and 59.6% for BC_AVF, and 65.0%, 68.4%, and 61.1% for BB_AVF (p = 0.29). Factors associated with lower primary and secondary patency were hemodialysis at time of arteriovenous fistula formation (p = 0.037 and p = 0.024, respectively) and higher Charlson Comorbidity Index (p = 0.036 and p < 0.001, respectively). Previous kidney transplant showed inferior primary patency (p = 0.005); higher age inferior secondary patency (p < 0.001). DISCUSSION Vascular access care remains challenging and salvage interventions are often needed to achieve maturation or maintain patency. Strict adherence to standardized outcome reporting in vascular access surgery paints a more realistic picture of arteriovenous fistula patency and enables reliable intercenter comparison

Perioperative echocardiography-guided hemodynamic therapy in high-risk patients: a practical expert approach of hemodynamically focused echocardiography

The number of high-risk patients undergoing surgery is growing. To maintain adequate hemodynamic functioning as well as oxygen delivery to the vital organs (DO2) amongst this patient population, a rapid assessment of cardiac functioning is essential for the anesthesiologist. Pinpointing any underlying cardiovascular pathophysiology can be decisive to guide inter ventions in the intraoperative setting. Various techniques are available to monitor the hemodynamic status of the patient, however due to intrinsic limitations, many of these methods may not be able to directly identify the underlying cause of cardiovascular impairment. Hemodynamic focused echocardiography, as a rapid diagnostic method, ofers an excellent opportunity to examine signs of flling impairment, cardiac preload, myocardial contractility and the function of the heart valves. We thus propose a 6-step-echocardiographic approach to assess high-risk patients in order to improve and maintain perioperative DO2. The summary of all echocardiographic based fndings allows a diferentiated assessment of the patient’s cardiovascular function and can thus help guide a (patho)physiological-orientated and individualized hemodynamic therapy

Clinicopathologic and molecular analysis of embryonal rhabdomyosarcoma of the genitourinary tract: evidence for a distinct DICER1-associated subgroup.

Embryonal rhabdomyosarcoma (ERMS) of the uterus has recently been shown to frequently harbor DICER1 mutations. Interestingly, only rare cases of extrauterine DICER1-associated ERMS, mostly located in the genitourinary tract, have been reported to date. Our goal was to study clinicopathologic and molecular profiles of DICER1-mutant (DICER1-mut) and DICER1-wild type (DICER1-wt) ERMS in a cohort of genitourinary tumors. We collected a cohort of 17 ERMS including nine uterine (four uterine corpus and five cervix), one vaginal, and seven urinary tract tumors. DNA sequencing revealed mutations of DICER1 in 9/9 uterine ERMS. All other ERMS of our cohort were DICER1-wt. The median age at diagnosis of patients with DICER1-mut and DICER1-wt ERMS was 36 years and 5 years, respectively. Limited follow-up data (available for 15/17 patients) suggested that DICER1-mut ERMS might show a less aggressive clinical course than DICER1-wt ERMS. Histological features only observed in DICER1-mut ERMS were cartilaginous nodules (6/9 DICER1-mut ERMS), in one case accompanied by foci of ossification. Recurrent mutations identified in both DICER1-mut and DICER1-wt ERMS affected KRAS, NRAS, and TP53. Copy number analysis revealed similar structural variations with frequent gains on chromosomes 2, 3, and 8, independent of DICER1 mutation status. Unsupervised hierarchical clustering of array-based whole-genome DNA methylation data of our study cohort together with an extended methylation data set including different RMS subtypes from genitourinary and extra-genitourinary locations (n = 102), revealed a distinct cluster for DICER1-mut ERMS. Such tumors clearly segregated from the clusters of DICER1-wt ERMS, alveolar RMS, and MYOD1-mutant spindle cell and sclerosing RMS. Only one tumor, previously diagnosed as ERMS arising in the maxilla of a 6-year-old boy clustered with DICER1-mut ERMS of the uterus. Subsequent sequencing analysis identified two DICER1 mutations in the latter case. Our results suggest that DICER1-mut ERMS might qualify as a distinct subtype in future classifications of RMS

Reference on copy number variations in pleomorphic xanthoastrocytoma: Implications for diagnostic approach

Pleomorphic xanthoastrocytoma (PXA) poses a diagnostic challenge. The present study relies on methylation-based predictions and focuses on copy number variations (CNV) in PXA. We identified 551 tumors from patients having received the histologic diagnosis or differential diagnosis pleomorphic xanthoastrocytoma (PXA) uploaded to the web page www.molecularneuropathology.org. Of these 551 tumors, 165 received the prediction “methylation class (anaplastic) pleomorphic xanthoastrocytoma” with a calibrated score &gt;=0.9 by the brain tumor classifier version v12.8 and, therefore, were defined the PXA reference set designated mcPXAref. In addition to these 165 mcPXAref, 767 other tumors received the prediction mcPXA with a calibrated score &gt;=0.9 but without a histological PXA diagnosis. The total number of individual tumors predicted by histology and/or by methylome based classification as PXA, mcPXA or both was 1318, and these were designated the study cohort. The selection of a control cohort was guided by methylation-based predictions recurrently observed for the other 386/551 tumors diagnosed as histologic PXA. 131/386 received predictions for another entity besides PXA with a score &gt;=0.9. Control tumors corresponding to the 11 most common other predictions were selected, adding up to 1100 reference cases. CNV profiles were calculated from all methylation datasets of the study and control cohorts. Special attention was given to the 7/10 signature, gene amplifications and homozygous deletion of CDKN2A/B. Comparison of CNV in the subsets of the study cohort and the control cohort were used to establish relations independent of histological diagnoses. Tumors in mcPXA were highly homogenous in regard to CNV alterations, irrespective of the histological diagnoses. The 7/10 signature commonly present in glioblastoma, IDH-wildtype, was present in 15-20% of mcPXA, whereas amplification of oncogenes (likewise common in glioblastoma) was very rare in mcPXA (&lt;1%). In contrast, the histology-based PXA group exhibited high variance in regard to methylation classes as well as to CNVs. Our data add to the notion, that histologically defined PXA likely only represent a subset of the biological disease