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Important network functions such as traffic classification and intrusion detection often depend on high-throughput regular expression matching. To achieve high performance, regular expressions can be represented as state machines, which are then merged. However, determining which individual state machines should ideally be merged together is a challenging optimization problem. We address this problem by using genetic algorithms with novel problem-specific operators. To allow large scale evaluation of the new operators, we devise two ML-based surrogate models for the expensive fitness evaluation function. Our results from a set of production scale regular expressions show that using the most appropriate operations provides large gains over a naive baseline, but also that no universal best combination of operators exist. We provide some insights into which operators perform best for different objectives, and show the variation between TCP- and UDP-specific regular expressions.

The position of the right ventricle (RV), often partly behind the sternum, implies difficulties to image the RV free wall using transthoracic echocardiography (TTE) and consequently limits the possibilities of stroke volume calculations. The aim of this study was to evaluate whether the volume of the right ventricle (RV) can be determined by combining TTE distance measurements that do not need the RV free wall to be fully visualized.The RV volume was approximated by an ellipsoid composed of three distances. Distance measurements, modeled RV stroke volumes (RVSV), and RV ejection fraction (RVEF) were compared to reference values obtained from cardiac magnetic resonance (CMR) imaging for 12 healthy volunteers.Inter-modality comparisons showed that distance measurements were significantly underestimated in TTE compared to CMR. The modeled RV volumes using TTE distance measurements were underestimated compared to reference CMR volumes. There was, however, for TTE an agreement between modeled RVSV and left ventricular stroke volumes determined by biplane Simpson's rule. Similar agreement was shown between modeled RVSV based on CMR distance measurements and the CMR reference. Regarding RVEF, further studies including patients with a wider range of RVEF are needed to evaluate the method.In conclusion, the ellipsoid model of the RV provides good estimates of RVSVs, but volumes based on distance measurements from different modalities cannot be used interchangeably.

Purpose: It has previously been shown that stroke volumes measured by transthoracic echocardiography (TTE) are underestimated, compared to cardiac magnetic resonance (CMR) imaging. The purpose of this study was to evaluate differences in distance and area measurements of the right atrium (RA) and the right ventricle (RV) by TTE and CMR.Methods: TTE examinations and CMR examinations were subsequently performed in 12 healthy volunteers. Three distances (RAL - right atrial length, RVIT3 - right ventricular inflow tract, RVLAX - right ventricular long axis) and one area (RVA - right ventricular area) were measured in TTE and CMR. Stroke volumes were also calculated using conventional methods available on each modality. Both intramodality and intermodality comparisons were performed based on measurements from three observers. One of the observers performed measurements in both TTE and CMR.Results: Intermodality comparisons showed that all distance and area measurements were significantly smaller using TTE (Table 1). Two of the measurements, RVIT3 and RVA, differed at about 50%. Calculated stroke volumes showed, consistent with previous results, that the TTE stroke volumes are substantially underestimated compared to CMR volumes. Intramodality variations of distance and area measurements were considerably smaller (Table 1).Conclusions: Our results show that RV distances and areas measured by TTE are smaller compared to CMR, probably due to differences in defining the endocardial borders. These differences subsequently result in smaller stroke volumes when using TTE. Caution should be taken when comparing distances, areas and volumes measured by TTE and CMR.

Purpose - The purpose of this study is to describe how to improve an organization’s desorptive capacity to facilitate knowledge transfer in transfer projects. Method - This research was conducted as a single case study, with an abductive approach, were the unit of analysis has been transfer projects. The empirical data collection has been qualitative and was conducted through 20 semi-structured interviews. The interviews were held at the case company with project managers, sub-project managers and project members to widen the experience of everyone involved in transfer projects. A thematic analysis was utilized to possess the empirical data. Result - We found that it is essential to evaluate critical factors in the identification of a transfer project and utilize managerial tools to facilitate the application of the knowledge transferred to the recipient. We have created a framework that show the correlations between the evaluation of the critical factors and the utilization of the managerial tools, categorized in organizational practices. Depending on the evaluation of the critical factors, resources need to be allocated to specific organizational practices. This will result in an improvement of an organization’s desorptive capacity. Theoretical contribution - This report contributes to the literature by filling the gap regarding how to improve organizations’ desorptive capacity to facilitate knowledge transfer in transfer projects. We have identified the critical aspects of desorptive capacity andcontributed with a framework that can be adapted by organizationsto improve their desorptive capacity. Managerial implications - The findings in this study have potential to increase the awareness among organizations about the initial phase of transfer projects and contribute to an increased understanding of how an organization can improve their desorptive capacity. It is recommended to utilize the presented framework in this report to take advantages of the correlations found between the critical factors and the organizational practices.

Takotsubo cardiomyopathy (TTC) is a condition of transient left ventricular (LV) dysfunction. The effects on LV mass (LVM) and geometry have not been studied enough in TTC. Retrospectively, we analyzed our TTC cohort both by transthoracic echocardiography (TTE) and magnetic resonance imaging (MRI), for comparative purposes.Thirteen women undergoing TTE and MRI, at onset and three months later, were included. LVM was estimated by MRI, and two TTE methods. Segmental wall thickness (SWT) was measured, while radial strain was assessed by TTE. Data analysis included Wilcoxon's test (between phases), Mann-Whitney U test and McNemar's test (between and within groups). Bland-Altman analyses were used for intertechnique coherence, while interactions regarding TTE were tested using Spearman's coefficient.LVM decreased during recovery (p0.05), by MRI and one of the TTE methods; truncated ellipsoid formula (TEF), which also showed relatively better coherence compared with MRI. SWT decreased in two of three sites, by both modalities, but with ambiguous coherence there between. The TEF data interacted partially with a demonstrated increase in radial strain.TTC associates with acute increase in LVM, which appears to be an apical effect, tending to follow the changes in concentric wall motion. MRI and TTE show adequate coherence; primarily for the TEF method regarding LVM.

Cigarettes and Swedish snuff influence the cardiovascular system in many ways. Cigarette and snuff usage have been linked with an acute impairment in several diastolic cardiac parameters during intake. The aim of this study is to investigate whether long-term usage of Swedish snuff or cigarettes also causes a more permanent impairment of systolic and/or diastolic cardiac parameters in the left ventricle in otherwise healthy middle-aged snuffers and smokers.Eighty-seven age-matched volunteers were included and examined with echocardiography. The volunteers were divided into three subgroups; one group with non-tobacco users, one group with long-term smokers and finally one group with long-term snuffers. The smokers and snuffers were instructed not to use these products for at least 5 h before the examination. The systolic and diastolic cardiac parameters were collected at one time. Most of the systolic parameters measured were unaltered between the tobacco subgroups and non-tobacco users, and therefore, no alteration of significance was found in systolic parameters. Also, almost all of the diastolic parameters measured were not significantly impaired in the tobacco subgroups compared with non-tobacco users. However, the deceleration time (DT) was slightly prolonged (P0·05) and thus statistically significant in the tobacco subgroups. This finding is somewhat difficult to interpret but may be seen as random.This study reveals that most systolic- and diastolic cardiac parameters are not chronically significantly altered in middle-aged long-term tobacco users compared with age-matched non-tobacco users.

Acute cardiac effects on the ventricular function in Swedish snuffers : an echocardiographic study

Takotsubo cardiomyopathy (TTC) is a disease characterized by transient left ventricular (LV) dysfunction and typical wall motion abnormalities in apical parts, without obvious signs of coronary influence. Due to its elusive natural cause and the lack of clarified pathology, further studies are needed. Thirteen patients presented with an episode of TTC, and referred to Orebro University Hospital (USO), were prospectively included and investigated by comparisons made at onset (acute phase) against at follow-up three months later (recovery phase). Including echocardiographic measurements, focused on biventricular systolic long-axis function and conventional diastolic function (DF) variables. Systolic improvement was shown, while most DF data were unchanged, suggesting that TTC is mainly a systolic disease affecting both ventricles.Diagnosis should include multidisciplinary engagement, as TTC associates both with emotional stress and pathological markers of physiological stress. In this thesis, such approach was offered to the aforementioned patients; to see if a common denominator could be found, thus, contributing to better handling. Emotional state was assessed, along with an array of cardiac investigations in addition to echocardiography. Acutely, imbalance in the autonomic cardiac control was shown, as well as a trend toward posttraumatic stress, but specific findings allowing conclusions on differential diagnosis could not be demonstrated.By adding another 15 TTC patients (i.e. 28 in total), through collaboration with observers from USA, a retrospective echocardiographic analysis could be done to further study DF; concluding that TTC associates with impairment of conventional DF variables which tends to parallel the systolic recovery, in contrary to the initial result but in line with other causesof LV dysfunction.Magnetic resonance imaging (MRI) is another method of choice at TTC. The USO patients had cardiac MRI, thus, a retrospective analysis was done to investigate the effect on LV geometry, both echocardiographic and by MRI; suggesting that TTC is consistently associated with increased LV mass, due to a local impact that seems to follow the change in LVconcentric wall motion.

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Takotsubo cardiomyopathy (TTC) is a condition of reversible left ventricular (LV) systolic dysfunction. However, the diastolic function (DF) manifestations of TTC have not been widely investigated. We performed a bicentric study with retrospective analysis of DF in patients with TTC, during onset and at follow-up.Twenty-eight patients with TTC (64 ± 10 years, F 24) were included. All underwent echocardiograms acutely and at the recovery phase (average three months later). Diastolic and systolic function parameters were recorded, including E-wave velocity (E), A-wave velocity, E/A ratio, relaxation (e') and contractility (S') based on tissue Doppler velocities of the mitral annuli, ejection fraction (EF), left atrial (LA) size and DF stages.Recovery, including the mean difference with 95% confidence interval, was associated with tending improvement (i.e. uncorrected significance) in E [13 cm s(-1) (-24, -2·3), P = 0·02] and in E/A ratio [0·2 (-0·41, -0·02), P = 0·04], as well as significant improvement (after multiple comparison correction) in mean e' [2·0 cm s(-1) (-3·3, -1·2), P0·001] and in A-wave duration [29 ms (-46·7, -12·7), P = 0·002]. LA area tended to decrease during recovery [-2 cm² (0·33, 2·4), P = 0·01]. Improvement in DF stages was significant between the phases (21% versus 58% defined as normal DF, P = 0·016). Improvement in LVEF correlated with improvement in mean e' (r = 0·52, P = 0·02).TTC is associated with an acute impairment of conventional DF variables, which improves during recovery. DF recovery seems to occur in parallel with systolic recovery in patients with TTC.

Takotsubo cardiomyopathy (TTC) is a disease characterized by transient left ventricular (LV) dysfunction and typical wall motion abnormalities in apical parts, without obvious signs of coronary influence. Due to its elusive natural cause and the lack of clarified pathology, further studies are needed. Thirteen patients presented with an episode of TTC, and referred to Örebro University Hospital (USÖ), were prospectively included and investigated by comparisons made at onset (acute phase) against at follow-up three months later (recovery phase). Including echocardiographic measurements, focused on biventricular systolic long-axis function and conventional diastolic function (DF) variables. Systolic improvement was shown, while most DF data were unchanged, suggesting that TTC is mainly a systolic disease affecting both ventricles. Diagnosis should include multidisciplinary engagement, as TTC associates both with emotional stress and pathological markers of physiological stress. In this thesis, such approach was offered to the aforementioned patients; to see if a common denominator could be found, thus, contributing to better handling. Emotional state was assessed, along with an array of cardiac investigations in addition to echocardiography. Acutely, imbalance in the autonomic cardiac control was shown, as well as a trend toward posttraumatic stress, but specific findings allowing conclusions on differential diagnosis could not be demonstrated. By adding another 15 TTC patients (i.e. 28 in total), through collaboration with observers from USA, a retrospective echocardiographic analysis could be done to further study DF; concluding that TTC associates with impairment of conventional DF variables which tends to parallel the systolic recovery, in contrary to the initial result but in line with other causesof LV dysfunction. Magnetic resonance imaging (MRI) is another method of choice at TTC. The USÖ patients had cardiac MRI, thus, a retrospective analysis was done to investigate the effect on LV geometry, both echocardiographic and by MRI; suggesting that TTC is consistently associated with increased LV mass, due to a local impact that seems to follow the change in LVconcentric wall motion.

Animal studies have shown a cardioprotective effect of blueberries after acute myocardial infarction (AMI). Bilberries (Vaccinium myrtillus), so-called Nordic blueberries, have a much higher content and diversity of anthocyanins compared to blueberries. To determine whether bilberries could have a

Cigarettes and Swedish snuff contain nicotine, which influence the cardiovascular system. Cigarette smoke has been shown to give an acute impairment in diastolic heart parameters. The systolic and diastolic heart function in snuff users is not thoroughly enough investigated. The aim of this study was to investigate if Swedish snuff will give an acute decrease in systolic and diastolic heart parameters in the left and right ventricles in healthy Swedish snuffers.Thirty healthy volunteers were examined with echocardiography. The study involved recordings from four different times: before snuff intake, 5 and 30 min after intake and finally 30 min after snuff withdrawal. The systolic and diastolic heart parameters were collected with conventional echocardiographic methods. In addition, the heart frequency and blood pressure response were measured. The pulse and blood pressure response were significantly altered (P0.01) during the test. Left ventricular ejection fraction and the amplitudes of mitral and tricuspid annulus motion did not alter significantly. The main finding in the study was the significant decrease (P0.05) in several diastolic heart parameters for both the left and right ventricles.This study shows that snuff intake causes a significant decrease in E/A ratio and a delay in ventricular relaxation and therefore a decrease in diastolic heart function in the left and right ventricles. The mechanism behind these alterations is probably very complex, but a combination of nicotine effects and loading conditions is probably the main factor.

Takotsubo cardiomyopathy is characterized by apical wall motion abnormalities without coronary stenosis. Limited information is available on the genesis of the underlying reversible contractile disorder. Our objective in this prospective study was to investigate biventricular changes in systolic long-axis function and diastolic parameters in the acute phase and after recovery. Thirteen consecutive patients were examined by echocardiography and coronary angiography at admission and again by echocardiography after 3 months. Amplitudes, systolic and diastolic velocities of the mitral and tricuspid annuli and conventional diastolic parameters were measured. Systolic long-axis shortening of the left ventricle (LV) and right ventricle (RV) improved from 9.6 ± 2.2 mm to 11.2 ± 1.9 mm (P = 0.02) and from 21.3 ± 3.6 mm to 24.1 ± 2.8 mm (P = 0·02), respectively. LV systolic, early and late diastolic velocities measured by pulsed-wave tissue Doppler also improved, while additional conventional diastolic parameters of the LV and RV diastolic function were unchanged. Takotsubo cardiomyopathy temporarily affects systolic LV and RV function, while most diastolic parameters remain unchanged.