Controlled generation of luminescent centers in hexagonal boron nitride by irradiation engineering

Luminescent centers in the two-dimensional material hexagonal boron nitride have the potential to enable quantum applications at room temperature. To be used for applications, it is crucial to generate these centers in a controlled manner and to identify their microscopic nature. Here, we present a method inspired by irradiation engineering with oxygen atoms. We systematically explore the influence of the kinetic energy and the irradiation fluence on the generation of luminescent centers. We find modifications of their density for both parameters, while a fivefold enhancement is observed with increasing fluence. Molecular dynamics simulations clarify the generation mechanism of these centers and their microscopic nature. We infer that V_NC_B and [Formula: see text] are the most likely centers formed. Ab initio calculations of their optical properties show excellent agreement with our experiments. Our methodology generates quantum emitters in a controlled manner and provides insights into their microscopic nature.

Nociception level-guided opioid administration in radical retropubic prostatectomy: a randomised controlled trial

BACKGROUND

This RCT investigated the effect of opioid titration by three different nociception monitoring devices or clinical signs during general anaesthesia.

METHODS

Ninety-six patients undergoing radical retropubic prostatectomy with propofol/remifentanil anaesthesia were randomised into one of four groups to receive remifentanil guided by one of three nociception monitoring devices (surgical pleth index [SPI], pupillary pain index [PPI], or nociception level [NOL]) or by clinical judgement (control). Intraoperative remifentanil requirement was the primary endpoint, whereas recovery parameters and stress hormone levels were secondary endpoints.

RESULTS

The mean [95% confidence interval {CI}] remifentanil administration rate differed between the groups: control 0.34 (0.32-0.37), SPI 0.46 (0.38-0.55), PPI 0.07 (0.06-0.08), and NOL 0.16 (0.12-0.21) μg kg^-1 min^-1(P<0.001). Intraoperative cessation of remifentanil administration occurred in different numbers (%) of patients: control 0 (0%), SPI 1 (4.3%), PPI 18 (75.0%), and NOL 11 (47.8%); P=0.002. The area under the curve analyses indicated differences in cumulative cortisol levels (mg L^-1 min^-1) amongst the groups: control 37.9 (33.3-43.1), SPI 38.6 (33.8-44.2), PPI 72.1 (63.1-82.3), and NOL 54.4 (47.6-62.1) (mean [95% CI]). Pairwise group comparison results were as follows: control vs SPI, P=0.830; control vs PPI, P<0.001; control vs NOL, P=0.001; SPI vs PPI, P<0.001; SPI vs NOL, P=0.002; and PPI vs NOL, P=0.009.

CONCLUSIONS

The nociception monitoring devices and clinical signs reflect the extent of nociception differently, leading to dissimilar doses of remifentanil. Very low remifentanil doses were associated with an increase and higher remifentanil doses were accompanied by a decrease in serum cortisol concentrations. Use of nociception monitoring devices for guiding intra-operative opioid dosing needs further validation.

CLINICAL TRIAL REGISTRATION

NCT03380949.

Epidemiology, clinical characteristics, and outcome of candidemia in critically ill patients in Germany: a single-center retrospective 10-year analysis

Background

Despite advances in the management of bloodstream infections (BSI) caused by Candida spp., the mortality still remains high in critically ill patients. The worldwide epidemiology of yeast-related BSI is subject to changing species distribution and resistance patterns, challenging antifungal treatment strategies. The aim of this single-center study was to identify predictors of mortality after 28 and 180 days in a cohort of mixed surgical and medical critically ill patients with candidemia.

Methods

Patients, who had been treated for laboratory-confirmed BSI caused by Candida spp. in one of 12 intensive care units (ICU) at a University hospital between 2008 and 2017, were retrospectively identified. We retrieved data including clinical characteristics, Candida species distribution, and antifungal management from electronic health records to identify risk factors for mortality at 28 and 180 days using a Cox regression model.

Results

A total of 391 patients had blood cultures positive for Candida spp. (incidence 4.8/1000 ICU admissions). The mortality rate after 28 days was 47% (n = 185) and increased to 60% (n = 234) after 180 days. Age (HR 1.02 [95% CI 1.01–1.03]), a history of liver cirrhosis (HR 1.54 [95% CI 1.07–2.20]), septic shock (HR 2.41 [95% CI 1.73–3.37]), the Sepsis-related Organ Failure Assessment score (HR 1.12 [95% CI 1.07–1.17]), Candida score (HR 1.25 [95% CI 1.11–1.40]), and the length of ICU stay at culture positivity (HR 1.01 [95% CI 1.00–1.01]) were significant risk factors for death at 180 days. Patients, who had abdominal surgery (HR 0.66 [95% CI 0.48–0.91]) and patients, who received adequate (HR 0.36 [95% CI 0.24–0.52]) or non-adequate (HR 0.31 [95% CI 0.16–0.62]) antifungal treatment, had a reduced mortality risk compared to medical admission and no antifungal treatment, respectively.

Conclusions

The mortality of critically ill patients with Candida BSI is high and is mainly determined by disease severity, multiorgan dysfunction, and antifungal management rather than species distribution and susceptibility. Our results underline the importance of timely treatment of candidemia. However, controversies remain on the optimal definition of adequate antifungal management.

[Thermographic monitoring of skin surface temperature associated with hot-iron disbudding in calves]

INTRODUCTION

The goal of this study was to determine the skin surface temperatures of the head using thermography in 28 German Holstein heifer calves at the time of hot iron disbudding. Calves were divided into group 1 (hot-iron disbudding, n = 14) and 2 (sham disbudding, n = 14). Thermographic measurements were made at eight locations of the head (area surrounding both horn buds, both horn buds, muzzle, mucous membranes of the muzzle, both eyes) at nine time points (- 60 min (basal value), time of disbudding, 5, 30, 60, 90, 120, 240 and 480 min after disbudding) using a high-end thermographic camera (ThermoPro TP8, Firma DIAS Infrared GmbH). The rectal temperature was measured 60 min before and 5, 240 and 480 min after disbudding. The statistical software SAS version 9.4 was used for analysis. Skin surface temperatures and rectal temperature correlated at several locations (rp ≥ 0.45; p ≤ 0.05). The maximum temperature (approx. 67 ºC) was measured at the horn buds immediately after the hot-iron procedure. By five and 30 min after hot-iron disbudding, the temperature of the horn buds had decreased by up to 50%, whereas the temperatures at the other locations had increased significantly (p.

New species of Phaeomoniellales from a German vineyard and their potential threat to grapevine (Vitis vinifera) health

Recently, the order Phaeomoniellales was established that includes fungi closely related to Phaeomoniella chlamydospora, a phytopathogen assumed to be the main causal agent of the two most destructive grapevine trunk diseases, Petri disease and esca. Other species of this order are reported as pathogens of other economically important crops, like olive, peach, apricot, cherry, plum, rambutan, lichee or langsat. However, they are rarely isolated and hence, little is known about their ecological traits and pathogenicity. During a 1-yr period of spore trapping in a German vineyard divided in minimally and intensively pruned grapevines, 23 fungal strains of the Phaeomoniellales were collected. Based on morphological and molecular (ITS, LSU and tub2) analyses the isolated strains were assigned to eight different species. Two species were identified as P. chlamydospora and Neophaeomoniella zymoides, respectively. The remaining six species displayed morphological and molecular differences to known species of the Phaeomoniellales and are newly described, namely Aequabiliellapalatina, Minutiella simplex, Moristroma germanicum, Mo. palatinum,Neophaeomoniella constricta and N. ossiformis. A pathogenicity test conducted in the greenhouse revealed that except for P. chlamydospora, none of the species of the Phaeomoniellales isolated from spore traps is able to induce lesions in grapevine wood.

[Perioperative stroke]

Perioperative stroke is defined as an ischemic cerebrovascular event that occurs during or within 30 days after surgery and is associated with an increased perioperative risk of morbidity and mortality. Depending on the type of surgery stroke is diagnosed in up to 11% of all patients in the perioperative period. Patients with a history of ischemic stroke or transitory ischemic attack have an increased risk for perioperative stroke. Therefore, a critical assessment of indications and the timing of surgery are crucial to prevent recurring stroke in this patient population. Importantly, individualized blood pressure management is essential for optimization of cerebral perfusion during the perioperative period.This article provides a summary of the epidemiology, risk factors, and etiology of perioperative stroke. Moreover, possible preventive strategies relevant for the anesthesiologist are reviewed.

Metabolic imaging: Analysis of different sections of white Asparagus officinalis shoots using high-resolution mass spectrometry

Many plant metabolism processes are currently not completely understood despite the numerous studies. These include the events in plant shoots and especially in the apical meristem. To understand the various mechanisms on a molecular level, a combined approach of target and non-targeted fingerprinting analysis was worked out on different white asparagus spear segments using high resolution mass spectrometry. By means of various multivariate analysis strategies, numerous distinctions within diverse substance classes were observed. While most of the investigated metabolites were present in relatively higher concentrations in the tip of the asparagus spears, others were more accumulated at the bottom, some, in turn, did not show any concentration differences along the shoot. Using pathway analysis, the most significant metabolites were classified in the biological context. To our knowledge for the first time, a non-targeted metabolomics approach is used with the aim of metabolic profiling of plant sprouts.

Comparing the effect of positioning on cerebral autoregulation during radical prostatectomy: a prospective observational study

Purpose

Surgery in the prolonged extreme Trendelenburg position may lead to elevated intracranial pressure and compromise cerebral hemodynamic regulation. We hypothesized that robot-assisted radical prostatectomy with head-down tilt causes impairment of cerebral autoregulation compared with open retropubic radical prostatectomy in the supine position.

Methods

Patients scheduled for elective radical prostatectomy were included at a tertiary care prostate cancer clinic. Continuous monitoring of the cerebral autoregulation was performed using the correlation method. Based on measurements of cerebral oxygenation with near-infrared spectroscopy and invasive mean arterial blood pressure (MAP), a moving correlation coefficient was calculated to obtain the cerebral oxygenation index as an indicator of cerebral autoregulation. Cerebral autoregulation was measured continuously from induction until recovery from anesthesia.

Results

There was no significant difference in cerebral autoregulation between robot-assisted and open retropubic radical prostatectomy during induction (p = 0.089), intraoperatively (p = 0.162), and during recovery from anesthesia (p = 0.620). Age (B = 0.311 [95% CI 0.039; 0.583], p = 0.025) and a higher difference between baseline MAP and intraoperative MAP (B = 0.200 [95% CI 0.073; 0.327], p = 0.002) were associated with impaired cerebral autoregulation, whereas surgical technique was not (B = 3.339 [95% CI  1.275; 7.952], p = 0.155).

Conclusion

Compared with open radical prostatectomy in the supine position, robot-assisted surgery in the extreme Trendelenburg position with capnoperitoneum did not lead to an impairment of cerebral autoregulation during the perioperative period in our study population.

Trial registration number: DRKS00010014, date of registration: 21.03.2016, retrospectively registered.

Electronic supplementary material

The online version of this article (10.1007/s10877-020-00549-0) contains supplementary material, which is available to authorized users.

[Thermographic examination of head surface temperatures of calves under field conditions]

INTRODUCTION

Thermographic examination of 157 German Holstein heifer calves was performed to investigate the feasibility of this technique for on-farm recording of surface temperature of the head and to examine potential factors that affect the recordings. Baseline values were obtained from six defined locations on the head including both eyes, both horn buds, the muzzle and the mucous membrane of the muzzle using a high-end thermographic camera (ThermoPro TP8, Firma DIAS Infrared GmbH). Evaluation of the influence of various factors on thermographic measurements showed that ambient temperature had the largest effect on surface temperature of the head (regression coefficient, 0.10 to 0.32, p ≤ 0.01) whereas humidity had no effect (in t-test p ≥ 0.33 over all locations). There was a no correlation between rectal temperature and surface temperature (rp ≤ 0.05). The surface temperature decreased with increasing age of the calves (regression coefficient, - 0.42 to - 0.14, p ≤ 0.01). The agreement between double readings made shortly after one another was excellent at all locations (r ≥ 0.95). The emission of infrared energy varied among different locations; the most infrared energy was emitted by the eyes and the least by the muzzle. Paired locations (eyes and horn buds) had symmetric emission patterns of infrared energy. Measuring the surface temperature of the head of calves in their normal barn environment using a standardised protocol was feasible and thus could potentially be used for monitoring calves under field conditions.

Postanesthesia care unit delirium following robot-assisted vs open retropubic radical prostatectomy: A prospective observational study

BACKGROUND

The aim of this study was to compare the incidence of early postoperative delirium in the postanesthesia care unit (PACU) between robot-assisted radical prostatectomy (RARP) in the extreme Trendelenburg position and open retropubic radical prostatectomy (ORP) in supine position.

METHODS

Patients were screened for delirium signs 15, 30, 45, and 60 minutes following extubation.

RESULTS

PACU delirium was present in 39.3% of RARP (64/163) patients and 41.8% of ORP (77/184) patients. Higher age (OR 1.072, 95%CI: 1.034-1.111, P < .001), total intravenous anesthesia (OR 2.001, 95%CI: 1.243-3.221, P = .004), and anesthesia duration (OR 1.255, 95%CI: 1.067-1.476, P = .006) were associated with PACU delirium, but no association was found between surgical technique and PACU delirium.

CONCLUSION

Compared with inhalational anesthesia, total intravenous anesthesia using propofol-sufentanil, higher age, and longer duration of anesthesia were associated with PACU delirium. Based on these findings, adverse effects on postoperative recovery and delirium signs do not have to be considered in the choice of surgical approach for radical prostatectomy.

TRIAL REGISTRATION

https://www.drks.de/, identifier: DRKS00010014.

Comparison of Cognitive Function After Robot-Assisted Prostatectomy and Open Retropubic Radical Prostatectomy: A Prospective Observational Single-Center Study

OBJECTIVE

To assess the effects of robot-assisted radical prostatectomy in the Trendelenburg position on postoperative neurocognitive outcomes this study compared cognitive function between patients who underwent robot-assisted radical prostatectomy and those who underwent open retropubic radical prostatectomy.

METHODS

Objective evaluations of pre- and postoperative cognitive function were performed upon admission and before hospital discharge, by using a neuropsychological test battery. We collected self-reported data on cognitive failures at 3 months postoperatively. Binary logistic regression analysis was used to assess the effects of surgical technique on postoperative cognitive performance.

RESULTS

The pre- and postoperative neuropsychological assessments were completed by 367 patients with a median age of 64 years (range 44-76). The incidence of postoperative cognitive dysfunction was 23.9% after robot-assisted (39/165) and 22.3% after open radical prostatectomy (45/202). There was no significant difference in postoperative cognitive function during the early postoperative period (P = 0.758) and self-reported cognitive failures at 3 months (P = 0.303) between robot-assisted and open surgery. Surgical technique was not associated with early postoperative cognitive dysfunction in multivariable analysis (OR 1.012, 95%CI: 0.608-1.685, P = 0.962).

CONCLUSION

Compared with open surgery in supine position postoperative neurocognitive disorders do not occur more frequently after robot-assisted radical prostatectomy in the extreme Trendelenburg position. Based on these findings potential adverse effects on cognitive function do not have to be considered in the choice of surgical approach for radical prostatectomy.

[Airway management in preclinical emergency anesthesia with respect to specialty and education]

BACKGROUND AND OBJECTIVE

Difficult airway management is a key skill in preclinical emergency medicine. A lower rate of subjective difficult airways and an increased success rate of endotracheal intubation have been reported for highly trained emergency physicians. The aim of this study was therefore to analyze the effect for different specialists and the individual state of training in the German emergency medical system.

MATERIAL AND METHODS

In a retrospective register analysis of 6024 preclinical anesthesia procedures, the frequencies of airway devices, neuromuscular blocking agents, capnography and difficult airways were analyzed with respect to specialization and status of training. Additionally, low, medium and highly experienced emergency physicians in airway management were summarized by specialization and status of training according to the Dreyfus model of skill acquisition and compared.

RESULTS

The incidence of subjective difficult airway situations was 10% for anesthesiological emergency physicians compared to 15-20% for other disciplines. The latter used supraglottic airway devices more often (7-9% vs. 4%) and video laryngoscopes less often (3% vs. 5%) compared to anesthesiological emergency physicians. The discipline-related state of training was inhomogeneous and revealed a reduced rate of supraglottic airway devices for internal specialists with further training (10% vs. 2%). Anesthetists specialized in intensive care medicine used capnography less frequently compared to other anesthetists (79% vs. 72%). With higher levels of experience in airway management, the frequency of endotracheal intubation (86% vs. 94%), neuromuscular blocking agents (59% vs. 73%) and video laryngoscopy (3% vs. 6%) increased and the incidence of subjective difficult airway situations (16% vs. 10%) decreased.

CONCLUSION

The level of training in airway management especially for non-anesthetists is inhomogeneous. The recently published German S1 guidelines for prehospital airway management recommend education and training as well as the primary use of the video laryngoscope with Macintosh blade. The implementation could lower the incidence of subjective difficult airways.