Optimizing home-based long-term intensive care for neurological patients with neurorehabilitation outreach teams - protocol of a multicenter, parallel-group randomized controlled trial (OptiNIV-Study).

BACKGROUND: Even with high standards of acute care and neurological early rehabilitation (NER) a substantial number of patients with neurological conditions still need mechanical ventilation and/or airway protection by tracheal cannulas when discharged and hence home-based specialised intensive care nursing (HSICN). It may be possible to improve the home care situation with structured specialized long-term neurorehabilitation support and following up patients with neurorehabilitation teams. Consequently, more people might recover over an extended period to a degree that they were no longer dependent on HSICN. METHODS: This healthcare project and clinical trial implements a new specialised neurorehabilitation outreach service for people being discharged from NER with the need for HSICN. The multicentre, open, parallel-group RCT compares the effects of one year post-discharge specialized outpatient follow-up to usual care in people receiving HSICN. Participants will randomly be assigned to receive the new form of healthcare (intervention) or the standard healthcare (control) on a 2:1 basis. Primary outcome is the rate of weaning from mechanical ventilation and/or decannulation (primary outcome) after one year, secondary outcomes include both clinical and economic measures. 173 participants are required to corroborate a difference of 30 vs. 10% weaning success rate statistically with 80% power at a 5% significance level allowing for 15% attrition. DISCUSSION: The OptiNIV-Study will implement a new specialised neurorehabilitation outreach service and will determine its weaning success rates, other clinical outcomes, and cost-effectiveness compared to usual care for people in need for mechanical ventilation and/or tracheal cannula and hence HSICN after discharge from NER. TRIAL REGISTRATION: The trial OptiNIV has been registered in the German Clinical Trials Register (DRKS) since 18.01.2022 with the ID DRKS00027326 .

On a variant of Pillai's problem involving S-units and Fibonacci numbers.

Let us denote by F n the n-th Fibonacci number. In this paper we show that there exist at most finitely many integers c such that the exponential Diophantine equation F n - 2 x 3 y = c has more than one solution ( n , x , y ) ∈ N 3 with n > 1 . Moreover, in the case that c > 0 we find all integers c such that the Diophantine equation has at least three solutions and in the case that c < 0 we find all integers c such that the Diophantine equation has at least four solutions.

Web-based apps for reflection: a longitudinal study with hospital staff.

BACKGROUND: Reflection is an important cognitive process in workplace learning; however, it occurs only rarely on its own and therefore needs additional support. OBJECTIVE: In this study, we investigated the effect of software applications (apps) that aim to support reflection on hospital staff's actual reflection behavior. In doing so, we also analyzed the relationship between reflection and the job satisfaction of health care professionals. METHODS: Reflective learning was introduced in the ward of a neurological hospital by providing apps that aimed to foster particular aspects of individual and collaborative reflection. Data were collected repeatedly: once before the introduction of the apps and again 2 years after the initial measure. We used a questionnaire with subjective ratings of reflection and job satisfaction. Response rates were 34.4% (167/485) for the first and 40.6% (210/517) for the second measure. RESULTS: Collaborative reflection was increased (P=.047) after the provision of the apps (2010: mean 2.84, SD 0.72; 2012: mean 3.06, SD 0.63) in contrast to a control group of other wards of the same hospital (2010: mean 2.68, SD 0.67; 2012: mean 2.63, SD 0.68). In addition, we revealed a positive correlation between collaborative reflection and job satisfaction (r=.61, P<.001). CONCLUSIONS: The findings provide evidence for an effect of the apps on hospital employees' reflection behavior. Apps that foster reflective learning can increase health care professionals' reflection about work experiences and support them in discussing experiences in teams or with their supervisors. The relationship between collaborative reflection and job satisfaction suggests that opportunities for joint reflection on work experiences in a hospital have further impact over and above fostering reflective learning per se. We discuss the limitations of our study and provide suggestions for both future research and the development of Web-based apps.

On Pillai's Problem involving Lucas sequences of the second kind.

In this paper, we consider the Diophantine equation Vn-bm=c for given integers b, c with b≥2, whereas Vn varies among Lucas-Lehmer sequences of the second kind. We prove under some technical conditions that if the considered equation has at least three solutions (n, m) , then there is an upper bound on the size of the solutions as well as on the size of the coefficients in the characteristic polynomial of Vn.

On prime powers in linear recurrence sequences.

In this paper we consider the Diophantine equation Un=px where Un is a linear recurrence sequence, p is a prime number, and x is a positive integer. Under some technical hypotheses on Un, we show that, for any p outside of an effectively computable finite set of prime numbers, there exists at most one solution (n, x) to that Diophantine equation. We compute this exceptional set for the Tribonacci sequence and for the Lucas sequence plus one.

Nous considérons dans cet article l'équation Un=px, où Un est une suite récurrente linéaire, p un nombre premier, et x un entier positif. Sous des hypothèses techniques, nous montrons que, pour tout p en dehors d'un ensemble fini calculable de nombres premiers, cette équation admet au plus une solution (n, x). Nous déterminons cet ensemble exceptionnel pour la suite de Tribonacci et pour la suite de Lucas plus un.

A low-profile wideband compressed single-arm spiral antenna array for mid-band 5G beam steering applications.

A low profile wideband spiral antenna array is presented for global mid-band 5G beam steering applications. In the global rollout of mid-band 5G, different frequencies have been licensed within each region (e.g. 3.4-3.8 GHz in the EU and 3.7-5 GHz in the USA). Therefore, antenna arrays must be able to cover a bandwidth of 3.3 GHz to 5 GHz to provide true global coverage. Initially, this work presents the design of a wideband compressed spiral antenna that provides an axial beam throughout its operational bandwidth of 3.3 GHz to 5 GHz, enabling beam steering functionality. Then, this antenna has been placed in a 4 × 4 array with a triangular lattice. The proposed spiral antenna array can provide a scanning range of - 40° ≤ θ ≤ + 40° in all azimuth directions with an average back lobe level of less than - 9.5 dB. This development will allow for low-cost integration of 5G systems for global use, such as passenger aircraft, UAVs, drones, and marine and ground vehicles.

Incidence of silent cerebral thromboembolic lesions after atrial fibrillation ablation may change according to technology used: comparison of irrigated radiofrequency, multipolar nonirrigated catheter and cryoballoon.

INTRODUCTION: Silent cerebral ischemic lesions have recently emerged as the most frequent complications after pulmonary vein isolation (PVI). To reduce thromboembolic complications, new types of catheters and energy source have been introduced in clinical practice. The study purpose is to compare the incidence of new silent cerebral ischemic events in patients with paroxysmal atrial fibrillation (PAF) undergoing PVI with different ablation technologies. METHODS AND RESULTS: One hundred and eight patients (67% men; age 56 ± 9 years) with PAF were enrolled in a consecutive manner to undergo PVI performed with irrigated radiofrequency (RF) catheter (Group 1, 36 patients), multielectrode catheter (PVAC) associated with duty-cycled RF generator (Group 2, 36 patients) and cryoballoon (Group 3, 36 patients). The protocol included a cerebral magnetic resonance imaging before and after the procedure. After PVI, the following patients showed new silent cerebral ischemic lesions at postprocedural cerebral MRI: 3 patients in Group 1 (8.3%), 14 patients in Group 2 (38.9%), 2 patients in Group 3 (5.6%). PVAC related to higher incidence of silent cerebral ischemic events compared to irrigated RF (P = 0.002) and cryoballoon (P = 0.001), whereas no statistical differences were found between irrigated RF catheter and cryoballoon groups (8.3% vs 5.6%, P = 0.5). At the multivariate analysis, the only independent predictor of new ischemic asymptomatic cerebral lesions after PVI was ablation performed with PVAC (OR 1.48 95% CI 1.19-1.62, P < 0.001). CONCLUSION: The incidence of silent cerebral lesions after PVI is different depending on technologies used: PVAC increases the risk of 1.48 times compared to irrigated RF and cryoballoon ablation.

Finding all S-Diophantine quadruples for a fixed set of primes S.

Given a finite set of primes S and an m-tuple ( a 1 , … , a m ) of positive, distinct integers we call the m-tuple S-Diophantine, if for each 1 ≤ i < j ≤ m the quantity a i a j + 1 has prime divisors coming only from the set S. For a given set S we give a practical algorithm to find all S-Diophantine quadruples, provided that | S | = 3 .

Integers representable as differences of linear recurrence sequences.

Let { U n } n ≥ 0 and { V m } m ≥ 0 be two linear recurrence sequences. We establish an asymptotic formula for the number of integers c in the range [ - x , x ] which can be represented as differences U n - V m . In particular, the density of such integers is 0.

Does anatomical completeness of the circle of Willis correlate with sufficient cross-perfusion during unilateral cerebral perfusion?

OBJECTIVES: The aim of the study was to evaluate the role of anatomical completeness of the circle of Willis for sufficient brain perfusion during unilateral cerebral perfusion and the methodology of the preoperative and intraoperative functional assessments of adequate cross-perfusion. METHODS: This prospective observational study included all elective patients (99) who underwent elective open arch surgery (hemiarch in 74 and arch replacement in 25 patients, respectively) at our institution between September 2004 and September 2006. Preoperative neuro-vascular evaluation included color-coded duplexsonography of the extracranial arteries, cranial CT angiography, and transcranial sonography. A functional test of cerebral cross-perfusion was performed during cross-clamping of the common carotid artery during cannulation by transcranial Doppler, electroencephalography and measurement of somatosensory evoked potentials. These examinations, which were completed through measurement of arterial pressure in both radial arteries, also served as an intraoperative assessment of cerebral perfusion during surgery. During mild hypothermic (30 degrees C) circulatory arrest with a mean duration of 18 min (range, 7-70) brain protection using unilateral cerebral perfusion was performed in all patients. RESULTS: As assessed in preoperative CT angiography, the circle of Willis was complete in only 59 patients. Eighteen patients showed a singular abnormal location within the circle of Willis, 13 patients presented with abnormalities within the posterior communicating arteries on both sides, and 9 patients within the anterior and posterior communicating arteries. Nevertheless, functional tests during carotid artery cross-clamping as well as intraoperative cerebral monitoring including transcranial Doppler showed no pathology in any patient, and only one patient with severe aortic valve calcification suffered from embolic minor stroke after surgery. CONCLUSIONS: The anatomical status of the circle of Willis assessed with cranial CT angiography does not correlate with functional and intraoperative tests examining the cerebral cross-perfusion. The authors do not recommend cranial CT angiography as a preoperative standard examination before open arch surgery in which unilateral cerebral perfusion is scheduled.

[Clinical symptoms and diagnostic imaging in moyamoya disease]. / Klinische Symptomatik und bildgebende Diagnostik bei der Moyamoya-Erkrankung.

OBJECTIVE: Presentation of typical imaging findings and diagnostic approaches in patients suspected of moyamoya disease. MATERIAL AND METHODS: Two female patients (24 resp. 44 years old) presenting with equivocal neurological symptoms (headache, recurrent monoparesis, choreiformic ataxia, grand mal seizure) were examined by means of colour-coded ultrasound, selective catheter-based angiography (DSA), CT and MRI including MR angiography. RESULTS: Cranial CT and MRI showed normal findings in one patient, and focal cerebral infarctions of different age in the other. In both cases, colour-coded ultrasound was indicative in detecting occlusive disease of the internal carotid arteries. Both, MR angiography as well as catheter-based angiography revealed the pathology of the culprid vessel, in addition catheter-based angiography was more accurate in depicting moyamoya collaterals at the skull base. CONCLUSION: In moyamoya disease colour-coded ultrasound is diagnostic for the lesion of the internal carotid artery, MRI resp. MRA depict the vascular and parenchymal lesion, whereas catheter-based DSA by providing information about the main vessel and collateral system allows the staging of the disease.

On linear combinations of units with bounded coefficients and double-base digit expansions.

Let [Formula: see text] be the maximal order of a number field. Belcher showed in the 1970s that every algebraic integer in [Formula: see text] is the sum of pairwise distinct units, if the unit equation [Formula: see text] has a non-trivial solution [Formula: see text]. We generalize this result and give applications to signed double-base digit expansions.

Malignant melanoma and nonmelanoma skin cancers in Northrhine-Westphalia, Germany: a patient- vs. diagnosis-based incidence approach.

BACKGROUND: Dermatologists have repeatedly criticized that the public health importance of nonmelanoma skin cancers is not appropriately reflected by the patient-based cancer incidence rates of population-based cancer registries. The aims of this study were to estimate the patient incidence rates of squamous cell carcinoma (SCC), basal cell carcinoma (BCC), and skin melanoma, and to study the effect of multiple primary skin tumors on the incidence rates. METHODS: We used a network of physicians covering a population of about 75,000 individuals to register all newly diagnosed invasive skin cancers (996 diagnoses in 796 patients), including BCC, SCC, and skin melanoma, from July 1998 to June 2003. We calculated age-standardized (world standard population) incidence rates (cases per 100,000 person-years) for the first diagnoses (called "patient incidence") and for any diagnoses of BCC, SCC, and skin melanoma (called "case incidence"). RESULTS: The patient incidence rates of BCC were 63.6 in men and 54.0 in women, and the case incidence rates of BCC were 82.7 and 71.1, respectively. The patient incidence rates of SCC were 17.4 in men and 9.7 in women, and the case incidence rates were 20.4 and 10.2, respectively. The patient and case incidence rates of skin melanoma were about the same at 13.6 in men and 18.5 in women. Twenty-five per cent of the BCC patients and 14% of the SCC patients suffered from more than one BCC and SCC, respectively, during the 5-year period. CONCLUSIONS: Patient incidence rates of BCC and SCC substantially underestimate the burden of nonmelanoma skin cancer in the population.