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This note contains reflections on a type of factorization that came up in the work of analytic operator valued functions by I.C. Gohberg and E.I. Sigal (cf. [14] , [10] , [11]). The determining characteristic of the factorizations in question is that they are obtained by the extraction of elementary factors of the form I − P + λ P where P is an idempotent in the underlying Banach algebra. It will be demonstrated here that there is a fundamental difference between the finite dimensional (matrix) case and the situation where infinite dimensional Banach algebras are taken into consideration. [ABSTRACT FROM AUTHOR]

The classical Rouché Theorem from complex function theory has been generalized to a result involving Fredholm operator valued functions (see [9] and [6]). The setting in question is (generally) a non-commutative one, so actually there are two versions of the generalization. In this paper, a unifying enhanced variant is presented involving the notion of the spectral radius. Its proof is based on a maximum principle for the spectral radius. An example is given showing that the enhanced Rouché Theorem presented here is a genuine improvement over the earlier version of the result. [ABSTRACT FROM AUTHOR]

Background: In the revisions for Paprosky type II femoral defects, diaphyseal fixating femoral stems are commonly used. To preserve bone stock, the use of a shorter primary conical stem could be an adequate alternative. The objective of this study is to compare the results of a primary conical stem to the more commonly used diaphyseal fixating modular revision stem in revision total hip arthroplasty surgery with Paprosky type II femoral defects.Methods: A total of 59 consecutive patients with Paprosky type II femoral defects from our prospective revision registry were included. Thirty patients who received a long distal fixating modular stem (Revision Stem, Lima Corporate) and 29 patients who received a primary conical short stem (Wagner Cone, Zimmer) were prospectively followed. Minimal follow-up time was 2 years for subsidence and patient-reported outcome measures and 5 years for complications, reoperation, and revision. We compared subsidence, perioperative complications, reoperations, femoral component survival, Oxford Hip Score, EuroQol 5 Dimension, visual analog scale (VAS) for pain at rest, and VAS for pain during activity between stems.Results: Both groups were comparable regarding demographic, clinical, and surgery-related characteristics. We found more perioperative complications and stem revisions with the modular revision stem than with the primary conical stem. There were no statistical differences in subsidence, EuroQol 5 Dimension, Oxford Hip Score, and VAS for pain at rest or during activity between both stems.Conclusion: In revision total hip arthroplasty with Paprosky type II femoral defects, uncemented primary monobloc conical femoral stems showed the same clinical result as distal fixating modular stems with fewer complications and fewer stem revisions. [ABSTRACT FROM AUTHOR]

Usage of combinatorial optimization for solving transportation problem of quantitative logistics is discussed. Aplication of this theory for human resource management, through optimal matching of quality supply and quality demand by sports clubs, is described.

Variants of the Two Machine Flow Shop Problem have been examined. In the variants, the makespan is known and the objective is to determine a schedule that meets the makespan, thereby minimizing obstacles to achieving the job. The max-variant and sum-variant are both linked with factorization problems for certain rational matrix functions. Flow shop problems involving the variants and the corresponding factorization problems have been found to be equivalent to a certain degree.

For a block upper triangular matrix, a necessary and sufficient condition has been given to let it be the sum of block upper rectangular matrices satisfying certain rank constraints; see [12]. The proof involves elements from Integer Programming (totally unimodular systems of equations playing a role in particular) and employs Farkas' Lemma. The linear space of block upper triangular matrices can be viewed as being determined by a special pattern of zeros. The present paper is concerned with the question whether the decomposition result can be extended to situations where other, less restrictive, zero patterns play a role. It is shown that such generalizations do indeed hold for certain directed graphs determining the pattern of zeros. The graphs in question are what will be called L -free. This notion is akin to other graph theoretical concepts available in the literature, among them the one of being N -free in the sense of [16]. [ABSTRACT FROM AUTHOR]

Extraction of metals in columns is scarce despite the advantage of low solvent inventory and the feasibility of high throughputs. Fast extraction kinetics allow short residence times and thus small apparatus height. A simulation of column concentration profiles via droplet population balances is less sophisticated as with surface active ion exchangers droplet breakage dominates and coalescence is hindered (rigid droplet surface). The extraction of Zn with D2EHPA (di(2-ethylhexyl)phosphoric acid) in a countercurrent Kühni column was investigated and the impact of different breakage kernels analyzed. Experiments in a lab scale test cell based on a DN32 Kühni extraction column geometry gave the basis to validate existing correlations and kernels for droplet breakage probability and daughter droplet size distribution. Since single droplet breakage tests were performed, a breakage dominated regime prevailed in the investigations. This yielded into a new unified correlation for the latter valid for different column geometries and physical and reactive extraction systems. As to this, a more firm basis for the simulation and design of stirred columns in hydrometallurgical application is established. [ABSTRACT FROM AUTHOR]

The synthesis of a novel class of piperazine benzamide (reverse amides) targeting the human β 3 -adrenergic receptor for the treatment of overactive bladder (OAB) is described. The SAR studies directed towards maintaining well established β 3 potency and selectivities while improving the overall pharmacokinetic profile in the reverse amide class will be evaluated. The results and consequences associated with functional activity at the norepinephrine transporter (NET) will also be discussed. [ABSTRACT FROM AUTHOR]

Objectives This study sought to understand and characterize the acute atrial response to endurance exercise and the influence of the amount of exercise performed. Background Endurance exercise seems to be recognized as a risk factor for developing atrial arrhythmia. Atrial geometrical and functional remodeling may be the underlying substrate. Methods Echocardiography was performed in 55 healthy adults at baseline and after a 3-stage trail race: a short race (S) (14 km), n = 17; a medium race (M) (35 km), n = 21; and a long race (L) (56 km), n = 17. Analysis consisted of standard, speckle-tracking assessment of both the left ventricle (LV) and right ventricle (RV) and both the left atrium (LA) and the right atrium (RA): a-wave strain (Sa) and strain rate (Ra) as a surrogate for atrial contractile function and s-wave strain (St) and strain rate (SR) as reservoir function. Results After the race, RA reservoir function decreased in group M (Δ% SRs: −12.5) and further in group L (Δ% SRs: −15.4), with no changes in group S. RA contractile function decreased in group L (Δ% SRa: −9.3), showed no changes in group M (Δ% SRa: +0.7), and increased in group S (Δ% SRa: +14.8). A similar trend was documented in LA reservoir and contractile function but with less pronounced changes. The decrease in RA reservoir after the race correlated with the decrease in RV global longitudinal strain (GLS) (Δ% RVGLS vs. RASt and RASRs: +0.44; p < 0.05 and +0.41, respectively; p < 0.05). Conclusions During a trail-running race, an acute exercise-dose dependent impairment in atrial function was observed, mostly in the RA, which was related to RV systolic dysfunction. The impact on atrial function of long-term endurance training might lead to atrial remodeling, favoring arrhythmia development. [ABSTRACT FROM AUTHOR]

Background Phosphatidylinositol 3-kinase p110δ isoform (PI3K p110δ) activity is essential for mast cell activation, suggesting that inhibition of PI3K p110δ might be useful in treating allergic diseases. Objective We sought to determine the effect of the PI3K p110δ–selective inhibitor idelalisib on allergic responses. Methods This phase 1 randomized, double-blind, placebo-controlled, 2-period crossover study was conducted with the Vienna Challenge Chamber. Grass pollen–induced allergic symptoms were documented during screening. Eligible subjects received idelalisib (100 mg twice daily) or placebo for 7 days, with allergen challenge on day 7. After a 2-week washout period, subjects received the alternate treatment and repeated allergen challenge. Study measures included safety, nasal and nonnasal symptoms, nasal airflow, nasal secretions, basophil activation, and plasma cytokine levels. Results Forty-one patients with allergic rhinitis received idelalisib/placebo (n = 21) or placebo/idelalisib (n = 20). Idelalisib treatment was well tolerated. Mean total nasal symptom scores were lower during the combined idelalisib treatment periods compared with placebo (treatment difference [idelalisib − placebo], −1.78; 95% CI, −2.53 to −1.03; P < .001). Statistically significant differences were also observed for the combined treatment periods for total symptom scores, nasal airflow, nasal secretion weight, and nasal congestion scores. The percentage of ex vivo –activated basophils (CD63 + /CCR3 + cells; after stimulation with grass pollen) was substantially lower for idelalisib-treated compared with placebo-treated subjects. Plasma CCL17 and CCL22 levels were reduced after idelalisib treatment. Conclusion Idelalisib treatment was well tolerated in patients with allergic rhinitis and appears to reduce allergic responses clinically and immunologically after an environmental allergen challenge. [ABSTRACT FROM AUTHOR]

Introduction Intrauterine growth restriction (IUGR) due to placental insufficiency is associated with blood-flow redistribution in order to maintain perfusion to the brain. However, some hemodynamic parameters that might be more directly related to staging of the disease cannot be measured non-invasively in clinical practice. For this, we developed a patient-specific model of the fetal circulation to estimate vascular properties of each individual. Methods A lumped model of the fetal circulation was developed and personalized using measured echographic data from 37 normal and IUGR fetuses to automatically estimate model-based parameters. A multivariate regression analysis was performed to evaluate the association between the Doppler pulsatility indices (PI) and the model-based parameters. The correlation between model-based parameters and the placental lesions was analyzed in a set of 13 IUGR placentas. A logistic regression analysis was done to assess the added value of the model-based parameters relative to Doppler indices, for the detection of fetuses with adverse perinatal outcome. Results The estimated model-based placental and brain resistances were respectively increased and reduced in IUGR fetuses while placental compliance was increased in IUGR fetus. Umbilical and middle cerebral arteries PIs were most associated with both placental resistance and compliance, while uterine artery PI was more associated with the placental compliance. The logistic regression analysis showed that the model added significant information to the traditional analysis of Doppler waveforms for predicting adverse outcome in IUGR. Discussion The proposed patient-specific computational model seems to be a good approach to assess hemodynamic parameters than cannot be measured clinically. [ABSTRACT FROM AUTHOR]

The dynamic behavior of particulate processes under the influence of the nonlinear aggregation term, nucleation, growth and breakup is studied. Analytic solutions are obtained from the integro-differential population balance equation governing the particle size distribution density function for special cases by the Adomian decomposition method (ADM) and are compared with other analytical solutions available in the literature. It avoids the difficulty numerical stability that often characterizes general numerical techniques in this area. It generates an infinite series which converges uniformly to the exact solution of the problem. For the case where there are no previous results a comparison between the present method and projection method which include collocation techniques is made. The results obtained indicate that the Adomian decomposition method is highly accurate, efficient and are useful for further work. [ABSTRACT FROM AUTHOR]

In elementary school, girls typically outperform boys in languages and boys typically outperform girls in math. The determinants of these differences have remained largely unexplored. Using rich data from Dutch elementary schools, we decompose the differences in achievement into gender differences in endowments and returns to IQ and non-cognitive factors. This descriptive analysis is a thought experiment in which we show the consequences for school performance if girls and boys had similar resources and took similar advantage of these resources. Our findings indicate that gender differences in resources with respect to social and instrumental skills and need for achievement can explain part of the differences in performance. Boys seem to be better equipped with these resources. Additionally, boys and girls employ their skills differently. Girls take more advantage of their IQ than boys. Yet, the largest part of this parameter effect is left unexplained by IQ and non-cognitive factors. [ABSTRACT FROM AUTHOR]

Abstract: Using families of irreducible Hilbert space representations as a tool, the theory of analytic Fredholm operator valued function is extended to a -algebra setting. This includes a -algebra version of Rouché’s Theorem known from complex function theory. Also, criteria for spectral regularity of -algebras are developed. One of those, involving the (generalized) Calkin algebra, is applied to -algebras generated by a non-unitary isometry. [Copyright &y& Elsevier]

Abstract: This article presents investigations to transfer an analytical batch electro-chromatography to a continuous annular electro-chromatography process. In order to study the electro-chromatographic effects of such a process a lab scale planar reference system was manufactured and tested. This planar device represents a fraction of the final annular geometry. An inorganic C8 reversed-phase monolith was filled between two glass plates as stationary phase inside a 1mm gap. The generation of Joule heating during the process was determined by using a contact-free thermal camera system. Additionally, the volume flow rate of the electrolyte was detected at the outlet geometry with a continuous imaging analysis system using the transmitted light method. Finally, a mixture of neutral test substances was used to evaluate the continuous separation and to compare the results of the planar plate with an analytical capillary. The obtained results indicate a uniform electro-osmotic flow as well as a successful separation of the test system and a good agreement between the efficiency of the planar gap and an analytical capillary electro-chromatographic device. [Copyright &y& Elsevier]

Abstract: Laser based measurement techniques were used to investigate the local velocities, the energy dissipation and the phase fraction inside a Kühni miniplant extraction column. The velocity field was determined with particle image velocimetry (PIV). The energy dissipation was obtained based on these measurements. The velocity measurements show that at extreme low dispersed phase flow the flow pattern alters extremely. The local time averaged phase fraction was measured with a laser induced fluorescence (LIF) system. It is shown that the accumulation underneath the stirrer has a high impact on the concentration of the dispersed phase in a single compartment. A higher rotational speed leads to a better distribution of droplets inside the column, whereas at lower stirring speed the droplets by-pass the impeller. Due to the shear force, especially near the stirrer outflow region, drop deformation and breakage occurs. [Copyright &y& Elsevier]

We present a 62-year-old man with acute and temporary paraparesis of the lower extremities as the solitary symptom of an anterior spinal artery syndrome caused by a type B aortic dissection. Ischemia of the spinal cord was confirmed by magnetic resonance imaging. Neurologic symptoms resolved completely within 6 hours and conservative treatment was successful up to 8 months follow-up. Our report illustrates that painless, transient neurologic deficit can be the only presenting symptom of acute aortic dissection and that aortic dissection should be part of the differential diagnosis of acute paraparesis. [ABSTRACT FROM AUTHOR]

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Percutaneous transluminal angioplasty (PTA) with stent placement is the preferred treatment modality at present for atherosclerotic stenotic lesions of vertebral artery origin. A complication of stent placement in the vertebral artery origin that has received little attention is the risk of stent fracture. A case with four-vessel pathology treated with PTA and stent placement in the left vertebral artery origin is presented. Symptoms recurred 4 months after stent placement, and arteriogram revealed a fractured stent, which was treated surgically with stent removal and vertebral artery–common carotid artery reimplantation. [ABSTRACT FROM AUTHOR]

Abstract: A new class of Banach algebra valued functions is identified for which the logarithmic residue with respect to a Cauchy domain vanishes (if and) only if the functions take invertible values in . Trace conditions and the extraction of elementary factors of the type play an important role. The class contains the Fredholm operator valued functions and the Banach algebra valued functions possessing a simply meromorphic resolvent as special instances. An example is given to show that new ground is covered and a long standing open problem is discussed from a fresh angle. [Copyright &y& Elsevier]

Abstract: Motivated by state space realizations of transfer functions from system theory, a number of operations on Schur complements are introduced and studied. These operations are equivalence, extension, multiplication, inversion, and factorization. Together they form an algebraic framework which is of independent interest, and also useful in solving problems in analysis. [Copyright &y& Elsevier]

The numerical solution of droplet population balance equations (PBEs) by discretization is known to suffer from inherent finite domain errors (FDE). Tow approaches that minimize the total FDE during the solution of discrete droplet PBEs using an approximate optimal moving (for batch) and fixed (for continuous systems) grids are introduced. The optimal grids are found based on the minimization of the total FDE, where analytical expressions are derived for the latter. It is found that the optimal moving grid is very effective for tracking out steeply moving population density with a reasonable number of size intervals. This moving grid exploits all the advantages of its fixed counterpart by preserving any two pre-chosen integral properties of the evolving population. The moving pivot technique of Kumar and Ramkrishna (Chem. Eng. Sci. 51 (1996b) 1333) is extended for unsteady-state continuous flow systems, where it is shown that the equations of the pivots are reduced to that of the batch system for sufficiently fine discretization. It is also shown that for a sufficiently fine grid, the differential equations of the pivots could be decoupled from that of the discrete number density allowing a sequential solution in time. An optimal fixed grid is also developed for continuous systems based on minimizing the time-averaged total FDE. The two grids are tested using several cases, where analytical solutions are available, for batch and continuous droplet breakage in stirred vessels. Significant improvements are achieved in predicting the number densities, zero and first moments of the population. [Copyright &y& Elsevier]

During coronary artery bypass surgery an intramyocardial or intracavitary left anterior descending coronary artery can be difficult to locate and pose problems of inadvertent entry into the right ventricle. We present a literature review of the management of this injury. We report an additional aid to prevent injury to the left anterior descending coronary artery during closure of the right ventriculotomy. [Copyright &y& Elsevier]

Background: We assessed the occurrence of neurological deficits that may impede the capacity to provide consent for trial participation in patients with an acute stroke, who are eligible for endovascular treatment (EVT).Methods: We used data from the Multicenter Randomized Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry, a prospective observational cohort study. We included 1526 patients with an anterior large vessel occlusion, undergoing EVT between March 2014 and June 2016. We based our assessment of decision-making capacity for trial participation on neurological symptoms influencing conditions concerning informed consent as stated in the declaration of Helsinki. We formulated a strict and a mild capacity assessment rule, using 2 different cut points in item scores on the National Institutes of Health Stroke Scale (NIHSS).Results: Applying the strict and mild rule, respectively 1469 (96%) and 1220 (80%) patients deemed not capable of decision-making for trial participation on admission, and 1077 (79%) and 825 (60%) patients at 24-48 hours after admission. Highest frequencies of predefined scores suggesting incapacity based on the strict rule were on the NIHSS items "Level of Consciousness Questions" (59%), "Best Gaze" (68%), and "Best Language" (58%). Patients who were considered incapable were older (median 71 versus 66 years, P = .043), had higher NIHSS scores (median 16 versus 8, P < .001), and had more often left hemisphere strokes (55% versus 28%, P < .001) than patients who were presumably capable.Conclusions: In the majority of patients with an anterior circulation stroke who are eligible for EVT, neurological deficits are present that may impede the capacity to provide informed consent for trial participation. [ABSTRACT FROM AUTHOR]

Purpose To compare set-up and 2-dimensional (2D) electronic portal imaging device (EPID) dosimetry data of breast cancer patients treated during voluntary moderately deep inspiration breath hold (vmDIBH) and free breathing (FB). Methods and materials Set-up data were analyzed for 29 and 51 consecutively treated patients, irradiated during FB and vmDIBH, respectively. Of the 51 vmDIBH patients, the first 25 had undergone an extra trained computed tomography (CT) scan and used an additional “breathing stick” (vmDIBH_trained). The last 26 patients did not use the breathing stick and did not undergo a trained CT (vmDIBH_untrained). The delivered 2D transit dose was measured with EPID in 15 FB and 28 vmDIBH patients and compared with a 2D predicted dose by calculating global gamma values γ using 5% and 5 mm as dose difference and distance-to-agreement criteria, respectively. Measurements with a percentage of pixels with an absolute gamma value > 1 (|γ| > 1) greater than 10% were classified as deviating. Results Only small, sub-millimeter differences were seen in the set-up data between the different patient groups. The mean of means, systematic error, and random error ranged from - 0.6 mm to 3.3 mm. The percentage of pixels with |γ| > 1 for all patients was 9.8% (2-25.8). No statistically significant differences were observed between the patient groups. In total, 38% of the gamma images were classified as deviating: 43.6% in vmDIBH_untrained patients compared with 38.0% in vmDIBH_trained patients and 33.3% in FB patients ( P > .05). Conclusion Both set-up and 2D EPID dosimetry data indicate that reproducibility of radiation therapy for patients treated during FB and vmDIBH is similar. Small but not significant differences in 2D EPID dosimetry were observed. Further investigation with 3-dimensional EPID dosimetry is recommended to investigate the clinical relevance of deviant gamma images. [ABSTRACT FROM AUTHOR]

Objective: Management and follow-up of chronic aortic dissections continue to be a clinical challenge due to progressive dilatation and subsequent rupture. To predict complications, guidelines suggest follow-up of aortic diameter. However, dilatation is triggered by hemodynamic parameters (pressures/wall shear stresses) and geometry of false (FL) and true lumen (TL), information not captured by diameter alone. Therefore, we aimed at better understanding the influence of dissection anatomy on TL and FL hemodynamics. Methods: In vitro studies were performed using pulsatile flow in realistic dissected latex/silicone geometries with varying tear number, size, and location. We assessed three different conformations: (1) proximal tear only; (2) distal tear only; (3) both proximal and distal tears. All possible combinations (n = 8) of small (10% of aortic diameter) and large (25% of aortic diameter) tears were considered. Pressure, velocity, and flow patterns were analyzed within the lumina (at proximal and distal sections) and at the tears. We also computed the FL mean pressure index (FPImean%) as a percentage of the TL mean pressure, to compare pressures among models. Results: The presence of large tears equalized FL/TL pressures compared with models with only small tears (proximal FPImean% 99.85 ± 0.45 vs 92.73 ± 3.63; distal FPImean% 99.51 ± 0.80 vs 96.35 ± 1.96; P < .001). Thus, large tears resulted in slower velocities through the tears (systolic velocity <180 cm/s) and complex flows within the FL, whereas small tears resulted in lower FL pressures, higher tear velocities (systolic velocity >290 cm/s), and a well-defined flow. Additionally, both proximal and distal tears act as entry and exit. During systole, flow enters the FL through all tears simultaneously, while during diastole, flow leaves through all communications. Flow through the FL, from proximal to distal tears or vice versa, is minimal. Conclusions: Our results suggest that FL hemodynamics heavily depends on cumulative tear size, and thus, it is an important parameter to take into account when clinically assessing chronic aortic dissections. [Copyright &y& Elsevier]