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The growth characteristics and the properties of undoped and nitrogen-doped single crystalline 6H-SiC thin films fabricated by chemica vapor deposition were investigated. The results showed that the doped layers featured high donor concentrations in the upper 10(super 4) square centimeter(super -3) range. Electron mobilities were measured at 370 square centimters per V s at room temperature.

Presents a study that examined the piezoelectric properties and elastic constants of 4H and 6H silicon carbide crystals. Methodology; Correlation between the elastic constants and the temperature; Determination of the resonance frequency of the crystals.

Objective: To assess the 12-month cost-effectiveness of the nurse-led transitional care program "Cardiolotse" (CL) for patients with cardiovascular diseases compared to usual care (UC)., Methods: A cost-effectiveness analysis (CEA) and cost-utility analysis (CUA) were conducted from the perspective of statutory health insurance (SHI), covering a time horizon of 12 months. Analyzed outcomes included the number of rehospitalizations and health-related quality of life (HRQoL). Total costs comprised program costs and the utilization of healthcare resources. Point estimates are presented as incremental cost-effectiveness ratios (ICERs) and incremental cost-utility ratios (ICURs). Sensitivity and subgroup analyses were conducted to illustrate uncertainty and provide insights into the impact mechanisms of the CL program., Results: The study population consisted of 2550 patients, with 1256 allocated to the intervention group and 1294 to the control group. Patients who received support from CLs experienced fewer rehospitalizations and lower inpatient costs from an SHI perspective, compared to the UC group. HRQoL assessments indicated higher utility values for CL patients at the 12-month follow-up. Total program costs amounted to €1454.65 per patient. The CEA and CUA demonstrate that the CL program is dominant compared to UC from the SHI perspective., Conclusion: Our study shows that the CL program not only reduces the number of rehospitalizations and costs but increases HRQoL, resulting in a dominant ICER and ICUR. Further research is necessary to evaluate longer periods of time, different levels of care intensity, and perspectives of different healthcare stakeholders., Trial Registration: German Clinical Trial Register DRKS00020424, 2020-06-18, retrospectively registered., (© 2024. The Author(s).)

Background: We conducted a prospective, randomized, controlled, two-group parallel trial investigating the effectiveness of a care management program employing cardiac care navigators providing post-discharge support to patients compared to standard care., Methods: The intervention commenced in 2019/2020 for 2862 patients hospitalized with heart failure, coronary heart disease, or cardiac arrhythmias in departments of cardiology across eight participating sites of a hospital group in Berlin, Germany. We analyzed the results using an intention-to-treat approach. The primary outcome was the all-cause rehospitalization rate after 12 months. Secondary outcomes included rehospitalizations due to one of the qualifying cardiac diagnoses, duration of rehospitalization, mortality, health-related quality of life, and several process indicators. Trial data were collected from a combination of face-to-face and phone interviews conducted by hospital staff throughout the 12-month follow-up period using standardized questionnaires. Administrative claims data were provided by a large statutory health insurer. Outcomes for the intervention and control groups were compared using logistic regression, generalized linear models (GLMs) with a negative binomial distribution, ordinary least squares, and Cox proportional hazards regression., Results: Compared to the control group (N = 1294), the intervention group (N = 1256) had a lower rate of all-cause rehospitalizations (62.6% vs. 66.4%, p = 0.05) and shorter lengths of stay (14.49 vs. 16.89 days, p = 0.02) during the 12-month follow-up period. These differences were also present for rehospitalizations due to the cardiac diseases qualifying for study recruitment, with rehospitalization rates for the intervention and control groups being 58.0% vs. 61.4% (p = 0.08) and particularly pronounced for lengths of rehospitalization stay of 12.97 vs. 15.40 days (p = 0.01), respectively. Subgroup analyses indicated positive effects of the intervention for patients 70 years and older (p = 0.05), females (p = 0.06), and those with little or no German language proficiency (p = 0.03). Furthermore, we found positive effects on patients' adherence to health-related behavioral recommendations (81.91% vs. 73.95%, p = 0.000)., Conclusions: This study adds to the body of evidence indicating that care management interventions supporting patients as they transition from the inpatient to the outpatient sector can lower rehospitalizations, decrease length of rehospitalization stays, and improve adherence to post-discharge recommendations., Trial Registration: German Clinical Trial Register, DRKS00020424 . Registered 2020-06-18. (retrospectively registered)., (© 2024. The Author(s).)

The hypothalamic arcuate nucleus (ARH) contains neurons vital for maintaining energy homeostasis that sense and respond to changes in blood-borne metabolic hormones. Despite its juxtaposition to the median eminence (ME), a circumventricular organ lacking a blood-brain barrier and thus exposed to circulating molecules, only a few ventral ARH neurons perceive these extravasating metabolic signals due to a poorly understood ME/ARH diffusion barrier. Here, we show in male mice that aggrecan, a perineural-net proteoglycan deposited by orexigenic ARH neurons, creates a peculiar ventrodorsal diffusion gradient. Fasting enhances aggrecan deposition more dorsally, reinforcing the diffusion barrier, particularly around neurons adjacent to fenestrated capillary loops that enter the ARH. The disruption of aggrecan deposits results in unregulated diffusion of blood-borne molecules into the ARH and impairs food intake. Our findings reveal the molecular nature and plasticity of the ME/ARH diffusion barrier, and indicate its physiological role in hypothalamic metabolic hormone sensing., (© 2024. The Author(s).)

Introduction: A lack of effective coordination and communication between ambulatory care physicians and hospitals, including the lack of follow-up care, poses a challenge to the recovery process of patients suffering from cardiac disease, often resulting in rehospitalisation and adverse outcomes. This innovative care programme aims to bridge the gap between ambulatory and hospital care. A key element of this programme is specifically trained care managers (Cardiolotse) who provide post-discharge support, access to additional resources and help the patient to navigate successfully through the healthcare system., Material and Methods: The study is set up as a prospective, randomised, controlled trial. Allocation to intervention group (support of care managers) and control group (usual care) follows an allocation ratio of 1:1 using block randomisation. Sample size calculations resulted in 1454patients per group after adjusting for potential non-compliance. All participants are surveyed at discharge, after 3 and 12 months. The primary outcome of the study is the 12-month rehospitalisation rate. Secondary outcomes include differences in length of hospital stay, mortality, quality-adjusted life years, costs and patient satisfaction. Statistical analysis and economic evaluation will be complemented by a process evaluation., Discussion: The new healthcare programme is designed to support patients when leaving hospital with cardiac conditions by easing the transition between sectors through access to Cardiolotses and individualised care plans. We hypothesise that the programme reduces rehospitalisation and improves clinically relevant patient outcomes., Trial Registration: German Clinical Trial Register, DRKS00020424. Registered 2020-06-18, http://www.drks.de/DRKS00020424., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Syngas from gasified organic waste materials is a promising feedstock for the biotechnological synthesis of the bioplastic poly([ R ]-3-hydroxybutyrate) (PHB) with Rhodospirillum rubrum . In a first approach, growth studies were carried out with this strain in gas-tight serum vials. When syngas (40% CO, 40% H 2 , 10% CO 2 , and 10% N 2 v/v) was diluted with N 2 to 60%, a 4-fold higher biomass production was detected compared to samples grown on 100% syngas, thus indicating a growth inhibitory effect. The best performing syngas-mixture was then used for C-, C,N-, and C,P-limited fed-batch fermentations in a bioreactor with continuous syngas and acetate supply. It was found that C,P-limited PHB productivity was 5 times higher than for only C-limited growth and reached a maximal PHB content of 30% w/w. Surprisingly, growth and PHB production stopped when N, as a second nutrient, became growth-limiting. Finally, it was concluded that a minimal supply of 0.2 g CO g -1 biomass h -1 has to be guaranteed in order to cover the cellular maintenance energy.

Recently, syngas has gained significant interest as renewable and sustainable feedstock, in particular for the biotechnological production of poly([R]-3-hydroxybutyrate) (PHB). PHB is a biodegradable, biocompatible polyester produced by some bacteria growing on the principal component of syngas, CO. However, working with syngas is challenging because of the CO toxicity and the explosion danger of H 2 , another main component of syngas. In addition, the bioprocess control needs specific monitoring tools and analytical methods that differ from standard fermentations. Here, we present a syngas fermentation platform with a focus on safety installations and process analytical technology (PAT) that serves as a basis to assess the physiology of the PHB-producing bacterium Rhodospirillum rubrum. The platform includes (i) off-gas analysis with an online quadrupole mass spectrometer to measure CO consumption and production rates of H 2 and CO 2 , (ii) an at-line flow cytometer to determine the total cell count and the intracellular PHB content and (iii) different online sensors, notably a redox sensor that is important to confirm that the culture conditions are suitable for the CO metabolization of R. rubrum. Furthermore, we present as first applications of the platform a fed-batch and a chemostat process with R. rubrum for PHB production from syngas., (© 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Poly(hydroxyalkanoates) (PHAs) are bacterial polyesters offering a biodegradable alternative to petrochemical plastics. The intracellular formation and degradation of PHAs is a dynamic process that strongly depends on the availability of carbon and other nutrients. Carbon excess and nitrogen limitation are considered to favor PHA accumulation, whereas carbon limitation triggers PHA depolymerization when all other essential nutrients are present in excess. We studied the population dynamics of Pseudomonas putida KT2440 at the single cell level during different physiological conditions, favoring first PHA polymerization during growth on octanoic acid, and then PHA depolymerization during carbon limitation. PHAs accumulate intracellularly in granules, and were proposed to separate preferentially together with nucleic acids, leading to two daughter cells containing approximately equal amounts of PHA. However, we could show that such P. putida KT2440 cells show bistable behavior when exposed to carbon limitation, and separate into two subpopulations: one with high and one with low PHA. This suggests an asymmetric PHA distribution during cell division under carbon limitation, which has a significant influence on our understanding of PHA mobilization., Competing Interests: The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.

Poly(3-hydroxyalkanoates) (PHAs) are bio-based and biodegradable polyesters which have been considered as a promising alternative to petrol-based plastics. Their bacterial production is a dynamic process in which intracellular polymerization and depolymerization are closely linked and depend on the availability of carbon substrates and other nutrients. These dynamics require a fast and quantitative method to determine the optimal harvest-time of PHA containing cells or to adjust carbon supply. In principle, flow cytometry (FCM) is an ideal tool that suits these requirements and, in addition, provides data on the PHA content of different cell populations. However, FCM-based PHA quantification methods have often relied on laborious sample preparation including washing steps and long incubation times. Here, we introduce a fast method based on double-staining using BODIPY 493/503 for PHA staining and SYTO 62 for DNA that allows acquiring reliable fluorescence and cell count data in <10min. Finally, fed-batch experiments with Pseudomonas putida KT2440 and Rhodospirillum rubrum S1 revealed that the method was robust and independent of the strain and type of PHA (medium-chain-length [mcl-] and short-chain-length [scl-] PHA, respectively). Interestingly, the specific PHA fluorescence was in case of mcl-PHA larger than for scl-PHA, probably reflecting the different material properties (e.g., specific density, hydrophilicity and crystallinity)., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Endovascular therapy of carotid artery disease has emerged as a potential alternative to endarterectomy and its clinical practise dramatically increased in many parts of the world. This study aims to determine the safety and mid-term outcome of carotid artery stenting (CAS) within a 15-year carotid program at a single-centre institution., Patients and Methods: We retrospectively analysed all CAS-procedures performed at our institution between 1995 and 2009., Results: During the observation period, a total of 497 CAS procedures were attempted in 460 patients with stenoses of the internal carotid artery of which 187 (37.6 %) were symptomatic and 310 (62.4 %) were asymptomatic. CAS was successful in 479 (96.4 %) cases and success rate significantly increased throughout the study (p < 0.001). The periprocedural complication rate for death, stroke, and transient ischemic attack (TIA) was 0.4 %, 1.2 %, and 2.6 %, respectively, and the cumulative event rate did not differ between symptomatic and asymptomatic patients (4.8 % vs. 3.9 %; p = 0.62). Age was the only significant predictor for the occurrence of any periprocedural adverse event (OR 2.08 [1.22 - 3.54]; p = 0.007). During a median follow-up of 24 [1; 141] months, the rate of stroke, TIA, and in-stent restenosis was 1.0 %, 2.2 %, and 2.7 %, respectively., Conclusions: Data from this large observation in everyday clinical patients demonstrate that endovascular therapy in carotid artery disease can be performed safely and with mid-term outcomes comparable to carotid endarterectomy.

Unlabelled: We studied the effects of the beta2-adrenoceptor and DA1-receptor agonist dopexamine on ventilation perfusion (V(A)/Q) distribution in anesthetized, paralyzed patients (n = 17) undergoing major abdominal surgery. Intrapulmonary shunt (Q(S)/Q(T)) (percentage of cardiac output [CO]), perfusion of low V(A)/Q areas (percentage of CO), ventilation of high V(A)/Q areas (percentage of total ventilation [V(E)]), and dead space ventilation [percentage of V(E)]) were calculated from the retention/excretion data of six inert gases. In the control state, Q(S)/Q(T) was 11% +/- 9% (mean +/- SD) and little perfusion of low V(A)/Q areas (3% +/- 4%) was observed. Infusion of 1.0 microg kg(-1) x min(-1) dopexamine had no effect on Q(S)/Q(T) and low V(A)/Q areas despite an increased CO (7.7 +/- 2.2 L/min versus 6.2 +/- 1.2 L/min; P < 0.01). Pao2 increased from 15.5 +/- 5.6 kPa (116 +/- 42 mm Hg) to 17.3 +/- 6.3 kPa (130 +/- 47 mm Hg) (P < 0.05). Infusion of 2.0 microg x kg(-1) x min(-1) dopexamine further increased CO to 8.4 +/- 2.7 L/min (P < 0.01) without alterations of Q(S)/Q(T), perfusion of low V(A)/Q areas, and Pao2. We concluded that dopexamine (1.0 microg x kg(-1) x min(-1) and 2.0 microg x kg(-1) x min(-1)) has no adverse effects on V(A)/Q relationships and Q(S)/Q(T) in anesthetized, paralyzed patients., Implications: The I.V. administration of vasoactive drugs can improve oxygen delivery to different organ systems but may impair pulmonary gas exchange. In anesthetized, paralyzed patients, we studied the effects of beta2-adrenoceptor and DA1-receptor agonist dopexamine on ventilation perfusion distribution. Dopexamine (1.0 microg x kg(-1) x min(-1) and 2.0 microg x kg(-1) min(-1)) improved cardiac output and oxygenation without alterations of intrapulmonary shunt.

Unlabelled: Life-threatening cardiovascular complications are a serious risk even for healthy patients during spinal/epidural anaesthesia. The incidence of fatal cardiovascular complications for epidural anaesthesia is 1:10000, for spinal anaesthesia 1:7000. In contrast, general anaesthesia has an overall mortality of only 1:28000. Administration of IV fluids to minimise the haemodynaemic reactions of beginning sympatholysis is not always sufficient. In this study, we examined whether fractionated application of local anaesthetics via a spinal catheter would provide better haemodynamic stability., Methods: In a prospective study, we examined the haemodynaemic reactions of 300 patients during single-dose (n = 150) versus continuous spinal anaesthesia (CSA) (n = 150). Isobaric bupivacaine 0.5% was given through a 29 G Quincke needle (3.5 ml) or a 28 G spinal catheter (1.5 ml as a bolus, followed by 1 ml/10 min until an anaesthetic level of T12 was reached)., Results: The sensory and motor effects of both methods were comparable. The T12 level of anaesthesia was achieved with the single-dose method after 10.5 min and with the continuous method after 19.1 min. After single-dose anaesthesia, the blood pressure dropped by 16.5% and the heart rate by 12% compared to the control values. During CSA no significant blood pressure changes were recorded; the heart rate decreased by 8%. In 15 cases vasoconstrictors had to be given to stabilise the lowered blood pressure after single-dose anaesthesia., Conclusion: With the use of CSA, the haemodynamic effects of sympatholysis can be minimised. This method thus has advantages, especially for high-risk cardiovascular patients.

Rationale and Objectives: We developed a technique for estimating the volumes of distribution and intratumoral ethanol concentrations using computed tomography (CT) scanning in patients undergoing percutaneous ethanol injection (PEI) treatment of malignant hepatic tumors., Methods: A phantom containing anhydrous ethanol diluted with deionized distilled water to concentrations of 0-100% ethanol was scanned by CT. Thirty-seven treatment sessions were performed on eight patients with malignant hepatic tumors undergoing PEI under CT guidance. The patients were scanned pre- and post-PEI, and a region of interest containing the treated hepatic tissue was selected for pixels between -250 and 15 Hounsfield units (H). The mean density of the pixels in this range was computed and the concentration of ethanol estimated. Volumes of distribution of ethanol and intratumoral concentration were then correlated with volume of ethanol injected during PEI. The ratios of volumes of distribution of ethanol to ethanol injected (adjusted in-range [IR]/volume injected) were compared for responders (n = 4) and nonresponders (n = 4)., Results: CT numbers in the phantom scaled linearly with ethanol concentration; 100% ethanol measured -234 H. On CT scans after PEI, the volume of distribution of ethanol correlated positively with the volume injected. Calculated intratumoral ethanol concentrations ranged from 4% to 31%. The adjusted IR/volume injected was significantly higher for responders than nonresponders (p < .5)., Conclusion: CT density data can be used to estimate volume of ethanol distribution in tissue; a larger relative intratumoral distribution of alcohol appears to correlate with a favorable response to PEI. However, CT measurement of intratumoral ethanol concentrations may require more complex computational techniques.