Total Number Of Segments Research Articles

Perception of Structure in Collective Free Improvisation and its Context Dependency: An Exploratory Analysis

This paper explores the hypothesis that similar structural notions can arise in different creative contexts, such as free improvisation and contemporary composition. Participants segmented a recorded improvisation into sequences based on personal criteria. Two groups were given different contexts: one group was informed the piece was a free improvisation, while the other was told it was a contemporary composition. Each participant analyzed one of 10 recordings. We aligned the segmentations by looking for overlaps within a specific time frame, Δt, considering segments simultaneous if they occurred within [t – Δt; t + Δt] of each other. Results indicated a high degree of similarity in perceived structure: 64% of segments overlapped within a 5-second frame, and 71% within 10 seconds. Additionally, the study found variations in the total number of segments and a correlation between sequence duration and the number of instruments used in the piece. These findings suggest that despite different contexts, there is a comparable perception of structural elements in musical pieces.

Realization of collimated specific profiles in rotation-symmetrical beam shaping system with divergent light source

A simple numerical method is proposed for the design of two aspherical surfaces, each comprising multiple segmented refractive planes, for generating a collimated beam with a specific irradiance profile in a beam shaping system with a divergent light source. However, in real-world manufacturing, this performance improvement is obtained at the expense of a greater cost and complexity. Accordingly, a second algorithm is proposed which maximizes the number of rays passing through the central regions of the refractive planes in the second aspherical surface and hence minimizes the total number of segments required to achieve the same beam shaping performance. The feasibility of the proposed method is demonstrated through the design of two aspherical lenses for generating collimated output beams with ring- and triangle-like irradiance profiles, respectively. The experimental results show that the beam profiles are in close agreement with the desired irradiance distributions. In general, the results indicate that the proposed method provides a versatile and efficient approach for achieving the desired collimated profile in beam forming systems with a divergent light source.

Personal Identification Using Long Short-Term Memory with Efficient Features of Electromyogram Biomedical Signals

This study focuses on personal identification using bidirectional long short-term memory (LSTM) with efficient features from electromyogram (EMG) biomedical signals. Personal identification is performed by comparing and analyzing features that can be stably identified and are not significantly affected by noise. For this purpose, 13 efficient features, such as enhanced wavelength, zero crossing, and mean absolute value, were obtained from EMG signals. These features were extracted from segmented signals of a specific length. Then, the bidirectional LSTM was trained on the selected features as sequential data. The features were ranked based on their classification performance. Finally, the most effective features were selected, and the selected features were connected to achieve an improved classification rate. Two public EMG datasets were used to evaluate the proposed model. The first database was acquired from eight-channel Myo bands and was composed of EMG signals from 10 varying motions of 50 individuals. The total numbers of segments for the training and test sets were 30,000 and 20,000, respectively. The second dataset consisted of ten arm motions acquired from 40 individuals. A performance comparison of the dataset revealed that the proposed method exhibited good performance and efficiency compared to other well-known methods.

Master Curve for the Dimensions of Statistical Network Polymers

AbstractThe graph diameter D is correlated with the mean‐square radius of gyration Rg2 and is a useful measure to design and control the network architecture. The fraction d of segments located in the diameter chain, defined by d = D/ns, where ns is the total number of segments in the polymer, is investigated for various statistical network polymers. It is found that the relationship between d and the cycle rank r of the well‐developed statistical networks follows a master curve. As a convenient measure to define the well‐developed networks, the network maturity index (NMI) is proposed. The random crosslinked networks with NMI > 3 are considered well‐developed, but a larger value of NMI is required for the nonrandom, heterogeneous networks. With the help of prior knowledge of the relationship between Rg2 and D, the master curve for the relationship between the contraction factor g and r can also be determined.

Anatomy of the coronary arteries and localization of coronary atherosclerosis in siblings with coronary heart disease

There is no doubt that there is a similar genetic predisposition in close relatives to the development of cardiovascular disease, while the features of coronary anatomy and possible commonality of pathological process in close relatives remain beyond research interest.
 Aim. To study the anatomy of the coronary arteries, the nature and severity of coronary lesion in pairs of male siblings suffering from coronary artery disease, in comparison with control pairs of patients who are not closely related.
 Materials and methods. This retrospective study included 87 male patients. The main group (58 patients or 29 couples) consisted of siblings with a horizontal hereditary burden for coronary artery disease. The control subgroup included 29 big brothers of the main group and another 29 patients who unrelated to them. To assess the degree of anatomy identity of the coronary bed in pairs of patients, we used a comparative characteristic of 25 segments of the coronary arteries (SyntaxScore). If there was similarity in anatomy and in the severity of the atherosclerotic process, each segment was assigned one point. In terms of the ratio of the total scores to the total number of segments (n=25), each pair of patients was assigned anatomical and atherosclerotic identity indexes.
 Results. According to the results of the study, the average indices of anatomical and atherosclerotic identity indexes were significantly higher in pairs of sibs compared to control pairs of patients (0.92 versus 0.88, p=0.008 and 0.92 versus 0.76, p0.001 respectively). When analyzing atherosclerotic lesions of the coronary arteries in pairs of sibs, a statistically significant coincidence of lesions in a number of segments of the coronary arteries was revealed, with the highest agreement in the left main coronary artery (=0.869, p0.001) and in the proximal segments of the main branches of the coronary arteries: left anterior descending artery (=0.786, p0.001) and right coronary artery (=0.812, p0.001). In the group of control pairs, such regularities were not revealed.
 Conclusion. In siblings with horizontal hereditary burden for coronary artery disease along the sibling line, the average anatomical and atherosclerotic identity indexes are significantly higher compared to control pairs. In pairs of siblings, there is the highest and most reliable probability of developing coronary atherosclerosis in the left main coronary artery and in the proximal segments of the left anterior descending artery and right coronary artery.

Association of Plaque Burden with Insulin Resistance Represented by Triglyceride - High Density Protein Ratio

BackgroundMultiple population-based studies has demonstrated that insulin resistance (IR) is strongly associated with coronary artery disease (CAD), plaque development, progression, and burden. Several surrogate biomarkers were used to assess for IR, such as hyperinsulinemic-euglycemic clamp, which still remains impractical in a clinical setting. We used simpler biomarkers as a surrogate for IR. MethodsWe identified 686 participants who were prospectively enrolled in Coronary computed tomography angiography (CCTA) clinical trials. Total Stenosis Score (TSS; the sum of maximal stenosis score per segment), Segment Involvement Score (SIS; the total number of segments with any plaque), and Total Plaque Score (TPS; the sum of the plaque amount per segment) were quantified by expert readers. These are the semi-quantitative methods used to assess plaque severity and burden. Multivariate linear regression was used to examine the association of TyG/HDL ratio, as a surrogate for IR, and its association to plaque burden. ResultsIn 686 subjects, the mean age was 54.6±13.9 years, 61% were male, mean body mass index (BMI) was 30.4±7.7, 54% had diabetes mellitus (DM), 62% had hyperlipidemia (HLD), 63% had hypertension (HTN), and 34% were past smokers. The mean Triglycerides level was 149.9±89.5 (mg/dL), mean HDL was 44.5±13.5, and mean Triglycerides/HDL ratio was 3.8±3.1. For every 1 unit increase in the TyG/HDL ratio, there is a 2% increase in TSS. And after adjusting for age, gender, BMI, DM, HLD, HTN, and past smoking, p=0.033. However, The TyG/HDL ratio and TPS and SIS were not significantly associated. ConclusionTyG/HDL ratio is associated with Total stenosis Score. Moreover, TyG/HDL ratio is a simple metric that can be used clinically, on a daily basis to further risk stratify and identify patients at risk for CAD.

Redescription of a rarely encountered species Travisachinensis Grube, 1869 (Annelida, Travisiidae), including a description of a new species of Travisa from Amoy, China.

The original description of Travisiachinensis Grube, 1869 was incomplete, leading to confusion with other species. To clarify the status of this species, we provide a redescription of, and remarks on, T.chinensis based on an examination of the type specimen. We also describe Travisiaamoyanus sp. nov., collected from Xiamen (Amoy), China, and originally identified as T.chinensis by Monro (1934). The new species can be distinguished from its congeners by a combination of the following characters: the total number of segments (34 or 35) and chaetigers (33 or 34), parapodial lappets first from chaetiger 15, and a pygidium with a large ventral triangular cirrus and about six encircling lateral cirri. Genetic distances and phylogenetic analyses based on the mitochondrial (16S rRNA) and nuclear (18S rRNA) genes support the identity of the new species.

Biochemical, coronary angiographic and echocardiographic parameters in inferior acute myocardial infarction with right ventricle injury

Background: The involvement of the right ventricular (RV) myocardium in inferior acute myocardial infarction (AMI) increases the risk of complication and death rates, which makes it important to timely identify this type of myocardial infarction.
 Aim: To assess the value of functional, biochemical, coronary angiographic and ultrasound parameters in the patients in their productive age with inferior AMI, in order to identify the RV injury before and after percutaneous coronary intervention (PCI).
 Materials and methods: This cohort prospective study included 141 patients with inferior AMI and ST elevation (26 women aged up to 60 years and 115 men aged up to 65 years), admitted to the emergency of the Medical Unit of Kazan (Volga region) Federal University from 2019 to 2021. The patients past history, clinical, biochemical and ultrasound data were obtained on admission and at discharge from the hospital. The two-dimensional speckle tracking echocardiography was performed at days 5 to 7 after PCI. The results are given as median values and 25% and 75% quartiles (Ме [Q1; Q3]).
 Results: According to electrocardiographic signs, 41.8% (n = 59) patients with inferior AMI comprised the group with the RV injury. There were no differences in the myocardial injury biomarker levels between the groups on admission (р = 0.31 and p = 0.786, respectively). The coronary angiography showed that the index artery was the right coronary artery in 100% (n = 59) cases with the RV injury and in 67.1% (n = 55, р 0.001) of the cases without the RV injury. Proximal involvement was 2.7 more common in biventricular infarction, than in the isolated inferior one (р = 0.013). During PCI, the RV involvement significantly increased the risk of complications (in 28 (47.5%) and 18 (22.0%) of the cases, respectively, р 0.001), among them being the need in a temporary pacemaker placement (8 (13.6%) and 2 (2.4%) patients, р = 0.027). Echocardiography showed worse parameters of global and local contractility of both ventricles in the group with the RV involvement in the inferior AMI. The left ventricular (LV) ejection fraction decreased from 55% [51; 57] to 52% [47; 56] (р = 0.005); global RV deformity from -15.2% [-18.5; -13.4] to -12.3% [-15.6; -10.6] (р 0.001); total number of segments with local contractility abnormalities increased from 2 [1; 3] to 5 [3; 6] (р 0.001).
 Conclusion: The study has confirmed that the involvement of RV into inferior LV AMI in the patients of productive age should be verified by abnormalities of electrocardiographic, biochemical, coronary angiographic and ultrasound parameters. To document the RV injury before PCI, ST elevation in additional right chest leads (V3RV4R) was most informative, whereas after PCI, it was the finding of abnormal local contractility of basal and medial inferior RV segments by two-dimensional echocardiography and decreased longitudinal RV deformation by speckle tracking.

Severe Impairment of Left Ventricular Regional Strain in STEMI Patients Is Associated with Post-Infarct Remodeling.

Background: Measures of global left ventricular (LV) systolic function have limitations for the prediction of post-infarct LV remodeling (LVR). Therefore, we tested the association between a new measure of regional LV systolic function—the percentage of severely altered strain (%SAS)- and LVR after acute ST-elevation myocardial infarction (STEMI). As a secondary objective, we also evaluated the association between %SAS and clinical events during follow-up. Methods: Of 177 patients undergoing echocardiography within 24 h from primary percutaneous coronary angioplasty, 172 were studied for 3 months, 167 for 12 months, and 10 died. The %SAS was calculated by dividing the number of LV myocardial segments with ≥−5% peak systolic longitudinal strain by the total number of segments. LVR was defined as the increase in end-diastolic volume >20% at its first occurrence compared to baseline. Results: LVR percentage was 10.2% and 15.8% at 3 and 12 months, respectively. Based on univariable analysis, a number of clinical, laboratory, electrocardiographic and echocardiographic variables were associated with LVR. Based on multivariable analysis, %SAS and TnI peak remained associated with LVR (for %SAS 5% increase, OR 1.226, 95% CI 1.098–1.369, p < 0.0005; for TnI peak, OR 1.025, 95% CI 1.004–1.047, p = 0.022). %SAS and LVR were also associated with occurrence of clinical events at a median follow-up of 43 months (HR 1.02, 95% CI 1.0–1.04, p = 0.0165). Conclusions: In patients treated for acute STEMI, acute %SAS is associated with post-infarct LVR. Therefore, we suggest performing such evaluations on a routine basis to identify, as early as possible, STEMI patients at higher risk.

Generalized Continuous Piecewise Linear Companding Transform Design for PAPR Reduction in OFDM Systems

Linear companding transform (LCT) is one of the most attractive schemes to deal with the inherent problem of high peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems, due to its effectiveness and low complexity. In this paper, a generalized continuous piecewise linear companding (CPLC) transform is proposed. The companding and decompanding functions of the proposed scheme consist of multiple continuous linear segments, and the total number of segments is generalized to be any integer not less than four. These linear segments can provide much adaptability for function shaping, leading to high flexibility for performance tradeoffs among PAPR reduction, bit error rate (BER), out-of-band (OOB) rejection and algorithmic complexity. The continuity of the companding function helps to reduce OOB radiations. Several optimization problems with different targets under the constraint condition of constant average power are constructed. Permissible ranges of key parameters, relationships among these parameters and their influence on algorithmic performance are analyzed. Parameter selecting strategies are also provided. In addition, an iterative receiving method is designed to reduce system BER effectively at the receiver. Simulation results validate the performance superiorities of the proposed scheme to that of other typical companding schemes.

Radiographic comparison of lordotic and hyperlordotic implants in L5-S1 anterior lumbar interbody fusion.

Anterior lumbar interbody fusion (ALIF) used at the lumbosacral junction provides arthrodesis for several indications. The anterior approach allows restoration of lumbar lordosis, an important goal of surgery. With hyperlordotic ALIF implants, several options may be employed to obtain the desired amount of lordosis. In this study, the authors compared the degree of radiographic lordosis achieved with lordotic and hyperlordotic ALIF implants at the L5-S1 segment. All patients undergoing L5-S1 ALIF from 2 institutions over a 4-year interval were included. Patients < 18 years of age or those with any posterior decompression or osteotomy were excluded. ALIF implants in the lordotic group had 8° or 12° of inherent lordosis, whereas implants in the hyperlordotic group had 20° or 30° of lordosis. Upright standing radiographs were used to determine all radiographic parameters, including lumbar lordosis, segmental lordosis, disc space lordosis, and disc space height. Separate analyses were performed for patients who underwent single-segment fixation at L5-S1 and for the overall cohort. A total of 204 patients were included (hyperlordotic group, 93 [45.6%]; lordotic group, 111 [54.4%]). Single-segment ALIF at L5-S1 was performed in 74 patients (hyperlordotic group, 27 [36.5%]; lordotic group, 47 [63.5%]). The overall mean ± SD age was 61.9 ± 12.3 years; 58.3% of patients (n = 119) were women. The mean number of total segments fused was 3.2 ± 2.6. Overall, 66.7% (n = 136) of patients had supine surgery and 33.3% (n = 68) had lateral surgery. Supine positioning was significantly more common in the hyperlordotic group than in the lordotic group (83.9% [78/93] vs 52.3% [58/111], p < 0.001). After adjusting for differences in surgical positioning, the change in lumbar lordosis was significantly greater for hyperlordotic versus lordotic implants (3.6° ± 7.5° vs 0.4° ± 7.5°, p = 0.048) in patients with single-level fusion. For patients receiving hyperlordotic versus lordotic implants, changes were also significantly greater for segmental lordosis (12.4° ± 7.5° vs 8.4° ± 4.9°, p = 0.03) and disc space lordosis (15.3° ± 5.4° vs 9.3° ± 5.8°, p < 0.001) after single-level fusion at L5-S1. The change in disc space height was similar for these 2 groups (p = 0.23). Hyperlordotic implants provided a greater degree of overall lumbar lordosis restoration as well as L5-S1 segmental and disc space lordosis restoration than lordotic implants. The change in disc space height was similar. Differences in lateral and supine positioning did not affect these parameters.

Fetal heart rate patterns in labor and the risk of neonatal encephalopathy: A case control study

ObjectiveTo describe the accuracy of intrapartum fetal heart rate abnormalities as defined by National Institute of Health and Care Excellence guidelines to predict moderate-severe neonatal encephalopathy of apparent hypoxic-ischemic etiology. Study designA case-control study of HIE risk factors was conducted. Eligible babies were born in a single maternity hospital in Dublin, Ireland between September 2006, and November 2017 at ≥35 + 0 weeks’ gestational age. Cases were eligible babies with moderate-severe neonatal encephalopathy of definite or apparent hypoxic-ischemic etiology. Controls were eligible babies born before and after each case with normal Apgar scores.The included subjects who had intrapartum fetal heart rate recordings were identified. Pattern features (baseline rate, variability, accelerations, decelerations [early, late, variable, prolonged], bradycardia, sinusoidal pattern) were manually identified blind to all clinical details by one of the authors. Each 15-minute segment was then algorithmically categorized (uninterpretable, normal, suspicious, pathological). ResultsOf 88 cases and 176 controls, 71 cases (81%) and 146 controls (83%) were admitted to the delivery suite in labor. From that group, intrapartum FHR traces longer than 15 min were available for 52 (73%) cases and 118 (83%) controls.The FHR pattern feature with the largest area under the receiver operating characteristic curve was the maximum number of consecutive segments in which the baseline was >160 bpm (0.71 [95% confidence interval: 0.62–0.80]). The category variable with the highest area under the curve was the number of suspicious segments (0.76 [95% confidence interval: 0.67–0.84]).A tri-variate logistic regression model incorporating the total number of segments, the number of “suspicious” segments classed, and the number of “pathological” segments achieved an area under the curve of 0.78 (95% confidence interval: 0.70–0.86). With 95% specificity, this model correctly identified 17 cases (33%) at a median time before delivery of 2 h and 18 min (interquartile range: 01:19–04:40). ConclusionsThe power of fetal heart rate analysis to predict neonatal encephalopathy is hampered by poor specificity given the rarity of the outcome. When analyzing a suspicious trace, it is beneficial to consider the overall duration of the suspicious pattern.

Pulmonary function changes after thoracoscopic lobectomy versus intentional thoracoscopic segmentectomy for early-stage non-small cell lung cancer.

BackgroundThoracoscopic segmentectomy is increasingly used in the surgical treatment of early-stage non-small cell lung cancer. However, it remains unclear whether pulmonary function loss after thoracoscopic lung resection is in direct proportion to the number of resected segments, and thus intentional thoracoscopic segmentectomy has the function-preserving advantage over thoracoscopic lobectomy.MethodsIn this prospective observational study, spirometry tests were performed preoperatively and 6 months postoperatively. The observed functional loss was compared with the expected loss estimated by the segment counting method. Resection extent index was introduced as the number of resected segments to total number of segments in the corresponding lobe. Spirometry changes after thoracoscopic lobectomy and intentional thoracoscopic segmentectomy were compared using propensity score matching.ResultsThere were 338 thoracoscopic lobectomies and 321 thoracoscopic segmentectomies. Overall, the observed pulmonary function loss after segmentectomy was significantly less than after lobectomy. But the observed functional loss was significantly greater than the expected loss after segmentectomy. And pulmonary function loss per segment resected was almost doubled after segmentectomy comparing to lobectomy. For segmentectomies with a resection extent index less than 0.5, especially single segmentectomies, pulmonary function loss was significantly less than after corresponding lobectomies. Otherwise, no significant differences in spirometry changes between lobectomies and segmentectomies were detected.ConclusionsPulmonary function loss after thoracoscopic lung resection cannot be accurately evaluated by the number of resected segments. According to the resection extent index, intentional thoracoscopic segmentectomy may help preserve more pulmonary function than thoracoscopic lobectomy only when less than half of the corresponding lobe are resected.

Dosimetric evaluation of physical parameters for different energies in advance radiotherapy technique for Liver cancer

ABSTRACT Introduction: This work aimed to study dosimetrically compare 6MV, 10MV and dual energies (DE) photon beam energies in liver cancer, evaluating the effect of using different of energies on intensity-modulated radiation (IMR) outcome were selected.IMRT treatment plans Identical optimization constraints were applied for all energy plans. The parameters like beam angle, number of beams, were kept constant to achieve the same clinical objectives. Both qualitative and quantitative methods were used. many physical indices for Planning Target Volume (PTV), the relevant Organs at Risk (OARs) as mean dose (Dmean), maximum dose (Dmax), 95% dose (D95), integral dose, total number of segments, and also the number of monitor unit (MU) were applied. Materials and methods: 28 virtual IMRT treatment planning were involved in this study. Step-and-shoot IMRT treatment plans were designed. Plans depended on Monaco (IMRT) treatment plan outcome. For each case, three plans with the same beam geometry were created using 6 MV, 10 MV and DE. For dual energy plans, all cases were optimized with identical planning objectives and normalized such 98% of the target received 100% of prescription dose. Results: The three techniques showed comparable PTV inhomogeneity and conformity for all patient’s differences within the median values <0.6%10 MV and DE plans also additionally a statistically important reduction in the total number of monitor units (MU) of 14.2% (p <0.01) and 13.3% (p <0.01) as compared to 6 MV, respectively. Conclusion: Each dual energy and 10 MV energy had similar PTV dosimetry characteristics.

Curve approximation by G1 arc splines with a limited number of types of curvature and length

A method for approximating planar curves by G1 continuous arc splines with a limited number of types of curvatures and lengths, named k-arc splines, is proposed. A k-arc spline is a particular arc spline, and it has only k types of arcs less than the total number of segments. Due to this property, k-arc splines require discrete variables that relate segments and k types of arcs for representation. Therefore k-arc spline approximation problems must deal with discrete variables in contrast to general arc spline approximation problems. The authors present a method to appropriately estimate these variables from curvature values of a target curve. The proposed method enables a formulation of the approximation problem as a continuous optimization problem that conventional optimization algorithms can solve efficiently. The estimation method also provides a suitable initial solution for the algorithms. Some examples to show the broad applicability of the proposed algorithm are shown.

A Modified\xa0Calculation Improves the Accuracy\xa0of Predicted Postoperative Lung Function Values in Lung Cancer Patients

PurposePreoperative pulmonary function testing is mandatory for non-small cell lung cancer (NSCLC) surgery. The predicted postoperative FEV1 (ppoFEV1) is used for further risk stratification. We compared the ppoFEV1 with the postoperative FEV1 (postFEV1) in order to improve the calculation of the ppoFEV1.Methods87 patients voluntarily received an FEV1 assessment 1 year after surgery. ppoFEV1 was calculated according to the Brunelli calculation. Baseline characteristics and surgical procedure were compared in a uni- and multivariate analysis between different accuracy levels of the ppoFEV1. Parameters which remained significant in the multinominal regression analysis were evaluated for a modification of the ppoFEV1 calculation.ResultsIndependent factors for a more inaccurate ppoFEV1 were preoperative active smoking (odds ratio (OR) 4.1, confidence interval (CI) 3.6–6.41; p = 0.01), packyears (OR 4.1, CI 3.6–6.41; p = 0.008), younger age (OR 1.1, CI 1.01–1.12; p = 0.03), and patients undergoing pneumectomy (OR 5.55, CI 1.35–23.6; p = 0.01). For the customized ppoFEV1 we excluded pneumonectomies. For patients < 60 years, an additional lung segment was added to the calculation. ppoFEV1 = preFEV1 × 1-left(frac{text{Lung segments resected} + 1}{text{Total number of segments}}right). For actively smoking patients with more than 30 packyears we subtracted one lung segment from the calculation ppoFEV1 = PreFEV1 × 1-left(frac{text{Lung segments resected} - 1}{text{Total number of segments}}right).ConclusionWe were able to enhance the predictability of the ppoFEV1 with modifications. The modified ppoFEV1 (1.828 l ± 0.479 l) closely approximates the postFEV1 of 1.823 l ± 0.476 l, (0.27%) while the original ppoFEV1 calculation is at 1.78 l ± 0.53 (2.19%). However, if patients require pneumectomy, more complex techniques to determine the ppoFEV1 should be included to stratify risk.

Serial right heart catheter assessment between balloon pulmonary angioplasty sessions identify procedural factors that influence response to treatment

Balloon pulmonary angioplasty (BPA) is delivered as a series of treatments for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) however, there is little published data on the procedural determinants of outcome.Pre- and post-BPA clinical and hemodynamic data, as well as serial hemodynamic and procedural data at each BPA session were evaluated to determine patient and procedure-related factors that influence hemodynamic response.Per procedure data from 210 procedures in 84 patients and per patient data from 182 procedures in 63 patients with completed treatment and 3-month follow-up were analyzed. A median of 3 (range 1-6) BPA procedures treating a median of 2 segments per procedure (range 1-3) were performed per patient with a median interval between procedures of 42 (range 5-491) days. Clinical outcome correlated with hemodynamic change (pulmonary vascular resistance [ΔPVR] vs Cambridge Pulmonary Hypertension Outcome Review [CAMPHOR] symptom score: p < 0.001, Pearson's r = 0.48, n = 49). Responders to BPA had more severe disease at baseline and 37.5 % of non-responders were post-PEA. There was a dose-response relationship between per procedure and total number of segments treated and hemodynamic improvement (ΔPVR: 1 segment: -0.9%, 2: -14.5%, 3 or more: -16.1%, p < 0.001). Treating totally occluded vessels had a greater hemodynamic effect (mean pulmonary artery pressure [ΔmPAP]: sessions with occlusion: -8.0%, without occlusion treated: -3.2%, p < 0.05) without an increased complication rate.The magnitude of clinical benefit is related to the hemodynamic effect of BPA which in turn is related to the number of segments treated and lesion severity. Patients who were post-PEA were less likely to respond to BPA.

Demarcation of arteriopulmonary segments: a novel and effective method for the identification of pulmonary segments.

ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy.

An Algorithm for Determining the Location of a Segment on a Segmented Image

The task of digital image analysis after image segmentation requires the ability to operate independently with each extracted segment (object), determine the total number of segments, and define the location of the segments on the image plane. This requires knowledge of the coordinates of each extracted segment on the image. This involves defining the coordinates of the pixels that make up the segment. For this purpose, an original algorithm was developed, which during the process of implementation of early developed non-parametric segmentation algorithm extracts the connected components (segments) on the image and determines the location of the each segment on the image based on the values of indices 𝑖 and 𝑗 (coordinates) of its pixels.

Association of flow mediated vasodilation and burden of subclinical atherosclerosis by coronary CTA

Background and aimsEndothelial dysfunction and atherosclerosis are linked by multiple mechanisms. Brachial artery flow-mediated dilation (FMD) rate is used to evaluate endothelial function and has been independently associated with adverse cardiac outcomes. The relationship between brachial artery FMD rate and severity of subclinical atherosclerosis by coronary computed tomography angiography (CCTA) is not understood. We hypothesized that brachial FMD is inversely associated with burden of subclinical atherosclerosis measured by CCTA. MethodsThis is a retrospective study of 100 participants with intermediate cardiac risk and atypical symptoms to examine association between brachial artery FMD rate and surrogate markers of severity of subclinical atherosclerosis on CCTA. Multivariate linear regression analysis was used to understand the relationship between brachial artery FMD rate and markers of plaque burden on CCTA including coronary artery calcium (CAC) score, segment involvement score (SIS; total number of segments with any plaque), segment stenosis score (SSS, sum of maximal stenosis score per segment), and total plaque score (TPS, the sum of all segments plaque burden). Results52 participants (42%) were female. Mean age of the cohort was 59.3 ± 10.4 years. After adjusting for traditional risk factors, brachial artery FMD rate was inversely associated with higher CAC, TPS, SIS and SSS (p < 0.05 for all). FMD <4.5 predicted the presence of CAC >0 and ≤ 100 most effectively, with a sensitivity of 62.2% and a specificity of 66.7%, respectively (area under the curve (AUC) of 0.5729, p = 0.0302). FMD <2.7 predicted the presence of CAC >100 most effectively, with a sensitivity of 34% and a specificity of 83% respectively (AUC of 0.6226, p = 0.0095). ConclusionsBrachial FMD is independently associated with the presence and extent of subclinical atherosclerosis on CCTA. Our findings provide more detailed evidence that mechanistically, FMD, a surrogate marker of systemic endothelial dysfunction is a correlate of atherosclerotic burden, assessed by CCTA and CAC.