Articles de revues : « P-concavità »

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Hou, Qing-hu, et Guojie Li. « Log-concavity of P-recursive sequences ». Journal of Symbolic Computation 107 (novembre 2021) : 251–68. http://dx.doi.org/10.1016/j.jsc.2021.03.004.

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Ahmia, Moussa, et Hacène Belbachir. « Preserving log-concavity for p,q-binomial coefficient ». Discrete Mathematics, Algorithms and Applications 11, n^o 02 (avril 2019) : 1950017. http://dx.doi.org/10.1142/s1793830919500174.

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We study the log-concavity of a sequence of [Formula: see text]-binomial coefficients located on a ray of the [Formula: see text]-Pascal triangle for certain directions, and we establish the preserving log-concavity of linear transformations associated to [Formula: see text]-Pascal triangle.

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Arazy, Jonathan, et Pei-Kee Lin. « On p-convexity and q-concavity of unitary matrix spaces ». Integral Equations and Operator Theory 8, n^o 3 (mai 1985) : 295–313. http://dx.doi.org/10.1007/bf01202902.

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Dodds, P. G., T. K. Dodds et F. A. Sukochev. « On p-Convexity and q-Concavity in Non-Commutative Symmetric Spaces ». Integral Equations and Operator Theory 78, n^o 1 (2 août 2013) : 91–114. http://dx.doi.org/10.1007/s00020-013-2082-0.

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Ranieri, V. Marco, Haibo Zhang, Luciana Mascia, Michael Aubin, Chang-Yi Lin, J. Brendan Mullen, Salvatore Grasso et al. « Pressure–Time Curve Predicts Minimally Injurious Ventilatory Strategy in an Isolated Rat Lung Model ». Anesthesiology 93, n^o 5 (1 novembre 2000) : 1320–28. http://dx.doi.org/10.1097/00000542-200011000-00027.

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Background We tested the hypothesis that the pressure-time (P-t) curve during constant flow ventilation can be used to set a noninjurious ventilatory strategy. Methods In an isolated, nonperfused, lavaged model of acute lung injury, tidal volume and positive end-expiratory pressure were set to obtain: (1) a straight P-t curve (constant compliance, minimal stress); (2) a downward concavity in the P-t curve (increasing compliance, low volume stress); and (3) an upward concavity in the P-t curve (decreasing compliance, high volume stress). The P-t curve was fitted to: P = a. tb +c, where b describes the shape of the curve, b = 1 describes a straight P-t curve, b < 1 describes a downward concavity, and b > 1 describes an upward concavity. After 3 h, lungs were analyzed for histologic evidence of pulmonary damage and lavage concentration of inflammatory mediators. Ventilator-induced lung injury occurred when injury score and cytokine concentrations in the ventilated lungs were higher than those in 10 isolated lavaged rats kept statically inflated for 3 h with an airway pressure of 4 cm H2O. Results The threshold value for coefficient b that discriminated best between lungs with and without histologic and inflammatory evidence of ventilator-induced lung injury (receiver-operating characteristic curve) ranged between 0.90-1.10. For such threshold values, the sensitivity of coefficient b to identify noninjurious ventilatory strategy was 1.00. A significant relation (P < 0.001) between values of coefficient b and injury score, interleukin-6, and macrophage inflammatory protein-2 was found. Conclusions The predictive power of coefficient b to predict noninjurious ventilatory strategy in a model of acute lung injury is high.

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Schmid, Annina B., Linda Dyer, Thomas Böni, Ulrike Held et Florian Brunner. « Paraspinal Muscle Activity During Symmetrical and Asymmetrical Weight Training in Idiopathic Scoliosis ». Journal of Sport Rehabilitation 19, n^o 3 (août 2010) : 315–27. http://dx.doi.org/10.1123/jsr.19.3.315.

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Context:Various studies report decreased muscle activation in the concavity of the curve in patients with scoliosis. Such decreased muscle-performance capacity could lead to sustained postural deficits.Objective:To investigate whether specific asymmetrical sports therapy exercises rather than symmetrical back strengthening can increase EMG amplitudes of paraspinal muscles in the concavity of the curve.Design:Cross-sectional.Setting:Laboratory.Participants:16 patients with idiopathic scoliosis.Interventions:Patients performed 4 back-strengthening exercises (front press, lat pull-down, roman chair, bent-over barbell row) during 1 test session. Each exercise was performed in a symmetrical and asymmetrical variant and repeated 3 times.Main Outcome Measure:EMG amplitudes of the paraspinal muscles were recorded in the thoracic and lumbar apexes of the scoliotic curve during each exercise. Ratios of convex- to concave-side EMG activity were calculated.Results:Statistical analysis revealed that the asymmetrical variants of front press at the lumbar level (P = .002) and roman chair and bent-over barbell row at the thoracic level (P < .0001, .001 respectively) were superior in increasing EMG amplitudes in the concavity of the scoliotic curve.Conclusions:Specific asymmetrical exercises increase EMG amplitudes of paraspinal muscles in the concavity. If confirmed in longitudinal studies measuring improvements of postural deficits, these exercises may advance care of patients with scoliosis.

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Schliemann, Benedikt, Michael Raschke, Philipp Michel, Lukas Heilmann, Felix Dyrna, Julia Sußiek, Andre Frank, Jan Katthagen et Jens Wermers. « It’s more than size that matters : The role of glenoid concavity in shoulder instability with anterior bone loss ». Orthopaedic Journal of Sports Medicine 9, n^o 7_suppl4 (1 juillet 2021) : 2325967121S0019. http://dx.doi.org/10.1177/2325967121s00198.

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Objectives: The mechanism of concavity-compression is known to be a key factor for glenohumeral stability in the mid-range of motion. This stabilizing effect is impaired by traumatic bone loss at the anterior glenoid rim. Currently, a critical threshold based on the defect size is used as a decisive criterion for surgical treatment. However, recent studies using finite element method (FEM)-simulations indicate that glenoid concavity is essential for an assessment of remaining glenohumeral stability. To date, there is no biomechanical investigation involving glenoid concavity in combination with defect size. In this biomechanical study we focused on the interdependence between glenoid concavity, defect size and glenohumeral stability. We hypothesized that glenohumeral stability is mainly dependent on concavity and that the initial concavity affects the loss of stability caused by bony defects at the anterior glenoid rim. Methods: A 6-degree-of-freedom industrial robot was utilized to determine the stability of 17 human cadaveric glenoids, depending on osteochondral concavity and anterior defect size. Load-and-shift tests were performed with artificial humeri equipped with a best-fit implant while joint positions and loads were captured. The Stability Ratio (SR), defined as the maximum tolerated anterior force related to a constant compression force, was determined for a compression of 50 N. In addition to a translation in 3 o’clock direction relative to a right scapula, a passive path dislocation was performed using compensatory translations to minimize superoinferior forces occurring during anterior translation. Defects were created in 2 mm steps parallel to the long axis of the glenoid until dislocation occurred self-acting and a 3D measuring arm was used for morphometric measurements as depicted in Figure 1. For statistical analysis, linear mixed-effects models were established to exploit the impacts of fixed effects (defect size and concavity gradient) as well as random effects (repeated measures and friction) on the SR. The influence of defect size on SR was analyzed for a translation in 3 o’clock by classifying the specimens into three groups of low (<25 %, n = 6), medium (25-35 %, n = 6) and high (>35 %, n = 5) initial concavity gradients. In addition, the Bony Shoulder Stability Ratio (BSSR), a characteristic based on glenoid depth and radius, was determined to evaluate its correlation with the measured SR and to find a suitable characteristic for the assessment of SR independent of defect size. Results: For a translation in 3 o’clock, the linear model resulted in an intercept of 7.13 ± 1.57 (95 % CI [4.01, 10.24]), representing the SR for zero defect size and concavity gradient. The linear coefficient for the predictor concavity gradient averaged 1.05 ± 0.05 (95 % CI [0.96, 1.14]) corresponding to a rise of SR by 1.05 % with each percentage of concavity gradient. Both coefficients were significantly different from zero with p<0.001. The defect size had only an indirect impact on SR, as the linear coefficient of 0.03 ± 0.04 (95 % CI [-0.10, 0.05]) differed insignificantly from zero (p = 0.53). The entire model featured a determination coefficient of R² = 0.98 and a mean squared error (MSE) of 4.22 %. This relationship is diagramed in Figure 2. Using the defect size as an exclusive predictor reduced R² to 0.87 and increased MSE up to 25.72 %. The passive path translation started on average in 2:16 o’clock for the intact glenoid and shifted to 3:06 o’clock with increasing defect size. Though the model indicated a significant impact of concavity gradient as well as defect size on SR (p<0.001), the influence of defect size ( 0.18 ± 0.03, 95 % CI [ 0.24, -0.11])) was significantly smaller than the effect of concavity gradient (0.97 ± 0.04, 95 % CI [0.88, 1.05]). However, the linear model for the passive path resulted in R² = 0.97 and MSE = 5.5 %. Separate linear models for the three groups of low, medium and high initial concavity gradients indicated significant differences in the slope coefficients (low: -0.55 ± 0.05 (95 % CI [ 0.65, 0.45]); medium: 0.78 ± 0.04 (95 % CI [-0.87, -0.70]); high: -1.25 ± 0.06 (95 % CI [ 1.36, -1.13])). This represented a significant impact of the initial glenoid concavity on the loss of SR per defect size. Raw data points as well as the linear approximations are shown in Figure 3. The linear model with the BSSR as a predictor for the measured SR is depicted in Figure 4 indicating a highly linear correlation with R² = 0.98 and MSE = 3.4 % for the translation in 3 o’clock. Conclusions: The SR is significantly dependent on the glenoid concavity whereas the defect size has a negligible indirect impact, provided that both predictors are included in a linear model. Due to constitutional different glenoid shapes, the loss of SR per defect size is significantly dependent on the initial concavity gradient. However, the BSSR has proven to be a reliable predictor of glenohumeral stability independent of defect size. These findings demonstrate that concavity is a crucial factor in estimating residual SR and substantiate that defect size as the only critical threshold is an inappropriate decisive criterion in the treatment of shoulder instabilities with anterior glenoid bone loss.

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Brzozowski, Michał. « Weighted exponential inequality for differentially subordinate martingales ». Archiv der Mathematik 116, n^o 6 (11 avril 2021) : 707–20. http://dx.doi.org/10.1007/s00013-021-01600-5.

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AbstractThe paper contains a study of weighted exponential inequalities for differentially subordinate martingales, under the assumption that the underlying weight satisfies Muckenhoupt’s condition $$A_{\infty }$$ A ∞ . The proof exploits certain functions enjoying appropriate size conditions and concavity. The martingales are adapted, uniformly integrable, and càdlàg - we do not assume any path-continuity restrictions. Because of this generality, we need to handle jump parts of processes which forces us to construct a Bellman function satisfying a stronger condition than local concavity. As a corollary, we will establish some new weighted $$L^p$$ L p estimates for differential subordinates of bounded martingales.

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Liu, Qian, Chenjiu Pang, Changgeng Liu, Wenjun Cheng, Shuai Ming, Wenwen Du et Xiaomei Feng. « Correlations among Corneal Biomechanical Parameters, Stiffness, and Thickness Measured Using Corvis ST and Pentacam in Patients with Ocular Hypertension ». Journal of Ophthalmology 2022 (3 décembre 2022) : 1–9. http://dx.doi.org/10.1155/2022/7387581.

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Background. To preliminary explore the correlations among corneal biomechanical parameters, stiffness, and thickness in patients with ocular hypertension (OHT) before and after treatment with topical antiglaucoma medications. Methods. This was a retrospective study that included 35 eyes with newly diagnosed OHT. Axial length (AL), apical corneal thickness, and minimum corneal thickness were measured using Pentacam. The lengths, velocities, and times of the first and second corneal applanations (A1L, A1V, A1T, A2L, A2V, and A2T, respectively); the highest concavity radius; highest concavity peak distance (PDHC); highest concavity deformation amplitude (DAHC); highest concavity time (HCT); pachymetry (PACH); stress-strain index (SSI); stiffness parameter-A1 (SP-A1); deformation amplitude ratio (DA ratio); integrated radius (IR); Ambrosio’s relational thickness horizontal (ARTh); corneal biomechanical index; noncorrected intraocular pressure (IOPnct); and biomechanically corrected IOP (bIOP) values were measured using the corneal visualization Scheimpflug technology (Corvis ST/CST). Results. After 5 weeks of treatment, Goldman applanation tonometer-IOP, IOPnct, bIOP, PACH, A1T, A2V, SSI, SP-A1, and ARTh decreased, but A1V, A2T, PDHC, DAHC, DA ratio, and IR increased significantly (all p < 0.05 ). SP-A1 and A1T were positively associated with premedication IOP and IOP changes, whereas A1V, A2T, PDHC, and IR were negatively associated (all p < 0.05 ). DAHC and DA ratio had significantly negative correlations with IOP variations. PDHC was found to be positively correlated with AL ( p < 0.05 ). A positive relationship was noted between SP-A1 and HCT before medication ( p < 0.05 ). Conclusions. SP-A1 was significantly and consistently associated with IOP. HCT might be correlated with SP-A1. SP-A1 and CST parameters could serve as potential biomarkers for evaluating OHT treatment efficacy.

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Kuang, Yao, et Raphael Douady. « Has the Market Started to Collapse or Will It Resist ? » Stats 5, n^o 2 (23 avril 2022) : 401–7. http://dx.doi.org/10.3390/stats5020023.

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Many people are concerned about the stock market in 2022 as it faces several threats, from rising inflation rates to geopolitical events. The S&P 500 Index has already dropped about 10% from the peak in early January 2022 until the end of February 2022. This paper aims at updating the crisis indicator to predict when the market may experience a significant drawdown, which we developed in Crisis Risk Prediction with Concavity from Polymodel (2022). This indicator uses regime switching and Polymodel theory to calculate the market concavity. We found that concavity had not increased in the past 6 months. We conclude that at present, the market does not bear inherent dynamic instability. This does not exclude a possible collapse which would be due to external events unrelated to financial markets.

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Guo, Laigang, Chun-Ming Yuan et Xiao-Shan Gao. « A Generalization of the Concavity of Rényi Entropy Power ». Entropy 23, n^o 12 (27 novembre 2021) : 1593. http://dx.doi.org/10.3390/e23121593.

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Recently, Savaré-Toscani proved that the Rényi entropy power of general probability densities solving the p-nonlinear heat equation in Rn is a concave function of time under certain conditions of three parameters n,p,μ, which extends Costa’s concavity inequality for Shannon’s entropy power to the Rényi entropy power. In this paper, we give a condition Φ(n,p,μ) of n,p,μ under which the concavity of the Rényi entropy power is valid. The condition Φ(n,p,μ) contains Savaré-Toscani’s condition as a special case and much more cases. Precisely, the points (n,p,μ) satisfying Savaré-Toscani’s condition consist of a two-dimensional subset of R3, and the points satisfying the condition Φ(n,p,μ) consist a three-dimensional subset of R3. Furthermore, Φ(n,p,μ) gives the necessary and sufficient condition in a certain sense. Finally, the conditions are obtained with a systematic approach.

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Fang, I.-Mo, Hsin-Yi Hsu, Wan-Ling Chiang, Yi-Ling Shih et Chia-Ling Han. « Correlation between Visual Acuity and Optical Coherence Tomography Angiography Parameters in Unilateral Idiopathic Epiretinal Membrane ». Journal of Clinical Medicine 10, n^o 1 (24 décembre 2020) : 26. http://dx.doi.org/10.3390/jcm10010026.

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Background: The tangential traction by idiopathic epiretinal membrane (iERM) may alter the hemodynamics of the macula. We investigated the correlation between visual acuity and the optical coherence tomography angiography (OCTA) parameters in unilateral iERM. Methods: We included 61 eyes of 61 consecutive patients with unilateral iERM between January 2018 and December 2018. The flow area of the retinal superficial capillary plexus (SCP), deep capillary plexus (DCP), and choroidal capillary plexus (CCP) were measured using OCTA. The normal fellow eyes were used for comparison. The iERM patients were divided into those with a presence of foveal concavity and those with a loss of foveal concavity. Results: When compared with fellow eyes, the flow areas showed a statistically significant decrease in the SCP and CCP of those with iERM (p = 0.037 and p = 0.011, respectively). In the DCP, no significant reduction in flow area was found in iERM (p = 0.054). The flow area of the CCP was the only factor significantly associated with best vision (p = 0.012). No significant differences in the flow areas of the SCP, DCP, and CCP were found between the presence and loss of foveal concavity. Conclusions: The flow area of the CCP is an important determinant of vision, emphasizing the crucial role of choroidal circulation in iERM. Moreover, mechanical stretch by iERM is not the only mechanism affecting the flow area.

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RUSKAI, MARY BETH. « LIEB'S SIMPLE PROOF OF CONCAVITY OF (A, B) ↦ Tr Ap K† B1-p K AND REMARKS ON RELATED INEQUALITIES ». International Journal of Quantum Information 03, n^o 03 (septembre 2005) : 579–90. http://dx.doi.org/10.1142/s0219749905001109.

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A simple, self-contained proof is presented for the concavity of the map (A, B) ↦ Tr Ap K† B1-p K. The author makes no claim to originality; this paper gives Lieb's original argument in its simplest, rather than its most general, form. A sketch of the chain of implications from this result to concavity of A ↦ Tr eK+ log A is then presented. An independent elementary proof is given for the joint convexity of the map [Formula: see text], which plays a key role in entropy inequalities.

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Ijaz, Moiza, Saira Ibrahim, Ayesha Aslam, Abdul Rehman, Sameena Younis et Ammara Shrafat. « Evaluation of Mandibular Ridge Lingual Concavity Using Cone Beam Computed Tomography ». Journal of Bahria University Medical and Dental College 10, n^o 1 (5 décembre 2019) : 22–25. http://dx.doi.org/10.51985/jbumdc2019062.

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Objective: To evaluate the type and depth of lingual concavity in posterior mandible using pre-treatment CBCT (Cone Beam Computed Tomography) images for dental implants. Study Design and Setting: A cross-sectional study was designed and conducted on pre-treatment CBCT scans of 75 patients at Armed Forces Institute of Dentistry, Rawalpindi, Pakistan from February 2018 to November 2018. Methodology: Pre-treatment CBCT scans of 75 patients were selected and following parameters were measured: type of ridge (undercut, parallel, convex), ridge width, ridge height, depth of lingual concavity, concavity angle, and location of the undercut. Data was analyzed using SPSS version .24. Post-stratification Mann-Whitney U test was used for effect modifiers, while Kruskal-Wallis test was used to compare study parameters between groups. P value <0.05 was taken as significant. Results: A mean concavity depth of 1.17±1.40 mm was observed while majority (46.7%) of the CBCT images presented with undercut type ridge. No significant difference was observed between males and females for any study parameter. Conclusion: Undercut ridges were frequently observed, posing a threat of lingual perforation during implant placement. Pre-operative assessment of implant site using CBCT can serve as a reliable method to avoid such complications

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Wolski, Grzegorz J., Paulina Nowicka-Krawczyk et William R. Buck. « Plagiothecium schofieldii, a new species from the Aleutian Islands (Alaska, USA) ». PhytoKeys 184 (5 novembre 2021) : 127–38. http://dx.doi.org/10.3897/phytokeys.184.69970.

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Plagiothecium schofieldiisp. nov. is described from the Aleutian Islands, Alaska, U.S.A. Some morphological features of this species correspond to P. lamprostachys (Southern Hemisphere species); however, Plagiothecium schofieldii is genetically and morphologically different from this and other common Northern Hemisphere species e.g., P. denticulatum, P. platyphyllum, or P. ruthei. The most important distinguishing morphological features differentiating this species are: the arrangement of the leaves on the stem; dimensions, concavity and symmetry of the leaves; dimensions of cells and their areolation; orientation of capsules. Additionally, due to the strong concavity of the leaves, they are very often badly damaged under the microscope. We present the results of DNA research of the analyzed samples, and a detailed description of the morphological features. The new species is illustrated, and its ecological preferences and currently known geographical distribution are presented. Additionally, the authors propose to add this species to Plagiothecium section, which is confirmed by morphological features and genetic analysis.

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Kuang, Yao, et Raphael Douady. « Crisis risk prediction with concavity from Polymodel ». Journal of Dynamics & ; Games 9, n^o 1 (2022) : 97. http://dx.doi.org/10.3934/jdg.2021027.

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Financial crises are an important research topic because of their impact on the economy, businesses, and populations. However, prior research tends to generate reactive systemic risk measures, in the sense that the measure surges after the crisis starts. Few of them succeed in warning of financial crises in advance. In this paper, we first sketch a toy model that produces normal mixture distributions based on a dynamic regime switching model. We derive that the relative concavity among various indices tends to increase before a crisis. Using Polymodel theory, we introduce a measure of concavity as a crisis risk indicator, and test it against known crises observed in the past. We validate this indicator by a trading strategy holding long or short positions on the S & P 500 Index, depending on the indicator value.

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Gibson, J. N. A., M. J. McMaster, C. M. Scrimgeour, P. J. Stoward et M. J. Rennie. « Rates of muscle protein synthesis in paraspinal muscles : Lateral disparity in children with idiopathic scoliosis ». Clinical Science 75, n^o 1 (1 juillet 1988) : 79–83. http://dx.doi.org/10.1042/cs0750079.

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1. The rate of paraspinal (multifidus) muscle protein synthesis was measured bilaterally at the top, apex and bottom of the thoracic curve in nine children with an idiopathic scoliosis, using the stable-isotope-labelled amino acid l-[1-13C]leucine. 2. No significant difference was observed in rates of muscle protein synthesis between the two sides of the spine, at the levels of the first vertebrae in neutral alignment at the top and bottom of the curve. However, in every patient, at the apex of the spinal curve, synthesis was higher on the convexity than on the concavity (0.077 ±0.04 %/h convex, 0.052 ±0.02 %/h concave, means ±sd, P < 0.01). 3. Muscle RNA activity (μg of protein synthesized h−1 μg−1 of RNA) was lower at the curve apices on the concave than the convex side (0.019 ± 0.09 μg h−1 μg−1 convex apex, 0.016 ±0.06 μg h−1 μg−1 concave apex, P < 0.05). Activities were similar on the two sides at the top and bottom of the curve. 4. Differences in muscle histology between the two sides were also observed only at the apex, with a lower type I fibre diameter (50.9 ±8.5 μm convex, 38.3 ±2.4 μm concave, P < 0.05) and a lesser proportion of type I fibres (63 ± 12% convex, 49 ±9% concave, P < 0.05) on the concavity. 5. The results are consistent with effects on muscle protein turnover secondary to an increased muscle contractile activity on the curve convexity and functional immobilization of the muscle on the curve concavity.

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Wang, Yu-Zhao, et Yan-Mei Wang. « The concavity of Rényi entropy power for the parabolic p-Laplace equations and applications ». manuscripta mathematica 160, n^o 3-4 (16 mars 2019) : 509–22. http://dx.doi.org/10.1007/s00229-019-01118-9.

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Nikoufar, Ismail. « A Perspective Approach for Characterization of Lieb Concavity Theorem ». Demonstratio Mathematica 49, n^o 4 (1 décembre 2016) : 463–69. http://dx.doi.org/10.1515/dema-2016-0040.

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Abstract Lieb’s extension theorem holds for generalized p + q ∈ [0; 1] and Ando convexity theorem holds for q - r > 1. In this paper, we give a complete characterization for concavity or convexity of Lieb well known theorem in the case where p + q ≥ 1 or p+q ≤ 0. We also characterize some auxiliary results including Ando theorem for q-r ≤ 1.

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Ranieri, V. Marco, Luciana Mascia, Tommaso Fiore, Francesco Bruno, Antonio Brienza et Rocco Giuliani. « Cardiorespiratory Effects of Positive End-expiratory Pressure during Progressive Tidal Volume Reduction (Permissive Hypercapnia) in Patients with Acute Respiratory Distress Syndrome ». Anesthesiology 83, n^o 4 (1 octobre 1995) : 710–20. http://dx.doi.org/10.1097/00000542-199510000-00010.

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Background In patients with acute respiratory distress syndrome (ARDS), the ventilatory approach is based on tidal volume (VT) of 10-15 ml/kg and positive end-expiratory pressure (PEEP). To avoid further pulmonary injury, decreasing VT and allowing PaCO2 to increase (permissive hypercapnia) has been suggested. Effects of 10 cmH2O of PEEP on respiratory mechanics, hemodynamics, and gas exchange were compared during mechanical ventilation with conventional (10-15 ml/kg) and low (5-8 ml/kg) VT. Methods Nine sedated and paralyzed patients were studied. VT was decreased gradually (50 ml every 20-30 min). Static volume-pressure (V-P) curves, hemodynamics, and gas exchange were measured. Results During mechanical ventilation with conventional VT, V-P curves on PEEP 0 (ZEEP) exhibited an upward convexity in six patients reflecting a progressive reduction in compliance with inflating volume, whereas PEEP resulted in a volume displacement along the flat part of this curve. After VT reduction, V-P curves in the same patients showed an upward concavity, reflecting progressive alveolar recruitment with inflating volume, and application of PEEP resulted in alveolar recruitment. The other three patients showed a V-P curve with an upward concavity; VT reduction increased this concavity, and application of PEEP induced greater alveolar recruitment than during conventional VT. With PEEP, cardiac index decreased by, respectively, 31% during conventional VT and 11% during low VT (P < 0.01); PaO2 increased by 32% and 71% (P < 0.01), respectively, whereas right-to-left venous admixture (Qs/Qt) decreased by 11% and 40%, respectively (P < 0.01). The greatest values of PaO2, static compliance, and oxygen delivery and the lowest values of Qs/Qt (best PEEP) were obtained during application of PEEP with low VT (P < 0.01). Conclusions Although PEEP induced alveolar hyperinflation in most patients during mechanical ventilation with conventional VT, at low VT, there appeared to be a significant alveolar collapse, and PEEP was able to expand these units, improving gas exchange and hemodynamics.

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Zuckerman, Scott L., Christopher S. Lai, Yong Shen, Nathan J. Lee, Mena G. Kerolus, Alex S. Ha, Ian A. Buchanan et al. « Incidence and risk factors of iatrogenic coronal malalignment after adult spinal deformity surgery : a single-center experience ». Journal of Neurosurgery : Spine 36, n^o 4 (1 avril 2022) : 585–94. http://dx.doi.org/10.3171/2021.6.spine21575.

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OBJECTIVE The authors’ objectives were: 1) to evaluate the incidence and risk factors of iatrogenic coronal malalignment (CM), and 2) to assess the outcomes of patients with all three types of postoperative CM (iatrogenic vs unchanged/worsened vs improved but persistent). METHODS A single-institution, retrospective cohort study was performed on adult spinal deformity (ASD) patients who underwent > 6-level fusion from 2015 to 2019. Iatrogenic CM was defined as immediate postoperative C7 coronal vertical axis (CVA) ≥ 3 cm in patients with preoperative CVA < 3 cm. Additional subcategories of postoperative CM were unchanged/worsened CM, which was defined as immediate postoperative CVA within 0.5 cm of or worse than preoperative CVA, and improved but persistent CM, which was defined as immediate postoperative CVA that was at least 0.5 cm better than preoperative CVA but still ≥ 3 cm; both groups included only patients with preoperative CM. Immediate postoperative radiographs were obtained when the patient was discharged from the hospital after surgery. Demographic, radiographic, and operative variables were collected. Outcomes included major complications, readmissions, reoperations, and patient-reported outcomes (PROs). The t-test, Kruskal-Wallis test, and univariate logistic regression were performed for statistical analysis. RESULTS In this study, 243 patients were included, and the mean ± SD age was 49.3 ± 18.3 years and the mean number of instrumented levels was 13.5 ± 3.9. The mean preoperative CVA was 2.9 ± 2.7 cm. Of 153/243 patients without preoperative CM (CVA < 3 cm), 13/153 (8.5%) had postoperative iatrogenic CM. In total, 43/243 patients (17.7%) had postoperative CM: iatrogenic CM (13/43 [30.2%]), unchanged/worsened CM (19/43 [44.2%]), and improved but persistent CM (11/43 [25.6%]). Significant risk factors associated with iatrogenic CM were anxiety/depression (OR 3.54, p = 0.04), greater preoperative sagittal vertical axis (SVA) (OR 1.13, p = 0.007), greater preoperative pelvic obliquity (OR 1.41, p = 0.019), lumbosacral fractional (LSF) curve concavity to the same side of the CVA (OR 11.67, p = 0.020), maximum Cobb concavity opposite the CVA (OR 3.85, p = 0.048), and three-column osteotomy (OR 4.34, p = 0.028). In total, 12/13 (92%) iatrogenic CM patients had an LSF curve concavity to the same side as the CVA. Among iatrogenic CM patients, mean pelvic obliquity was 3.1°, 4 (31%) patients had pelvic obliquity > 3°, mean preoperative absolute SVA was 8.0 cm, and 7 (54%) patients had preoperative sagittal malalignment. Patients with iatrogenic CM were more likely to sustain a major complication during the 2-year postoperative period than patients without iatrogenic CM (12% vs 33%, p = 0.046), yet readmission, reoperation, and PROs were similar. CONCLUSIONS Postoperative iatrogenic CM occurred in 9% of ASD patients with preoperative normal coronal alignment (CVA < 3 cm). ASD patients who were most at risk for iatrogenic CM included those with preoperative sagittal malalignment, increased pelvic obliquity, LSF curve concavity to the same side as the CVA, and maximum Cobb angle concavity opposite the CVA, as well as those who underwent a three-column osteotomy. Despite sustaining more major complications, iatrogenic CM patients did not have increased risk of readmission, reoperation, or worse PROs.

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Zeng, Fugeng, Qigang Deng et Dongxiu Wang. « Global Existence and Blow-Up for the Pseudo-parabolic p(x)-Laplacian Equation with Logarithmic Nonlinearity ». Journal of Nonlinear Mathematical Physics 29, n^o 1 (30 septembre 2021) : 41–57. http://dx.doi.org/10.1007/s44198-021-00010-z.

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AbstractIn this paper, we study the initial boundary value problem of the pseudo-parabolic p(x)-Laplacian equation with logarithmic nonlinearity. The existence of the global solution is obtained by using the potential well method and the logarithmic inequality. In addition, the sufficient conditions of the blow-up are obtained by concavity method.

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Ma, Xi-Nan, et Wei Zhang. « The Concavity of the Gaussian Curvature of the Convex Level Sets of $$p$$ p -Harmonic Functions with Respect to the Height ». Communications in Mathematics and Statistics 1, n^o 4 (décembre 2013) : 465–89. http://dx.doi.org/10.1007/s40304-014-0025-y.

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Simić, Slavko, et Vesna Todorčević. « Jensen Functional, Quasi-Arithmetic Mean and Sharp Converses of Hölder’s Inequalities ». Mathematics 9, n^o 23 (1 décembre 2021) : 3104. http://dx.doi.org/10.3390/math9233104.

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In this article, we give sharp two-sided bounds for the generalized Jensen functional Jn(f,g,h;p,x). Assuming convexity/concavity of the generating function h, we give exact bounds for the generalized quasi-arithmetic mean An(h;p,x). In particular, exact bounds are determined for the generalized power means in terms from the class of Stolarsky means. As a consequence, some sharp converses of the famous Hölder’s inequality are obtained.

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Zhong, Genhong, Xiaoyan Ma et Fei Wang. « Approximations related to the complete p-elliptic integrals ». Open Mathematics 20, n^o 1 (1 janvier 2022) : 1046–56. http://dx.doi.org/10.1515/math-2022-0493.

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Abstract In this paper, the authors present some monotonicity properties for certain functions involving the complete p-elliptic integrals of the first and second kinds, by showing the monotonicity and concavity-convexity properties of certain combinations defined in terms of K p {{\mathscr{K}}}_{p} , E p {{\mathscr{E}}}_{p} and the inverse hyperbolic tangent arth p {{\rm{arth}}}_{p} , which is of importance in the computation of the generalized pi and in the elementary proof of Ramanujan’s cubic transformation. By these results, several well-known results for the classical complete elliptic integrals including its bounds and logarithmic inequalities are remarkably improved.

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Chung, Soon-Yeong, et Min-Jun Choi. « A new condition for the concavity method of blow-up solutions to p-Laplacian parabolic equations ». Journal of Differential Equations 265, n^o 12 (décembre 2018) : 6384–99. http://dx.doi.org/10.1016/j.jde.2018.07.032.

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Ye, Yaojun, et Qianqian Zhu. « Existence and nonexistence of global solutions for logarithmic hyperbolic equation ». Electronic Research Archive 30, n^o 3 (2022) : 1035–51. http://dx.doi.org/10.3934/era.2022054.

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<abstract>This article is concerned with the initial-boundary value problem for a equation of quasi-hyperbolic type with logarithmic nonlinearity. By applying the Galerkin method and logarithmic Sobolev inequality, we prove the existence of global weak solutions for this problem. In addition, by means of the concavity analysis, we discuss the nonexistence of global solutions in the unstable set and give the lifespan estimation of solutions.</abstract>

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Jayachandran, Sushmitha, et Gnanavel Soundararajan. « p-Biharmonic Pseudo-Parabolic Equation with Logarithmic Non linearity ». 3C TIC : Cuadernos de desarrollo aplicados a las TIC 11, n^o 2 (29 décembre 2022) : 108–22. http://dx.doi.org/10.17993/3ctic.2022.112.108-122.

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This paper deals with the existence of solutions of a p-biharmonic pseudo parabolic partial differential equation with logarithmic nonlinearity in a bounded domain. We prove the global existence of the weak solutions using the Faedo-Galerkin method and applying the concavity approach, that the solutions blow up at a finite time. Further, we provide a maximal limit for the blow-up time.

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Greenstein, Alexander, Alexander M. Brown, Aaron Roberts, Raymond Edward Chen, Emma Knapp et Ilya Voloshin. « Double-Row Repair Technique Provides Improved Dynamic Stabilization over Single-Row Repairs for Acute Bony Bankart Lesions ». Orthopaedic Journal of Sports Medicine 7, n^o 7_suppl5 (juillet 2019) : 2325967119S0043. http://dx.doi.org/10.1177/2325967119s00437.

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Objectives: Previous studies of bony Bankart repair comparing single- and double-row reconstruction techniques have examined static forces required to displace the bony Bankart lesion. No studies, to date, have examined stability of bony Bankart repair with more physiologic concavity-compression model. We hypothesize the double-row fixation technique would provide superior stability and decreased displacement of a simulated bony Bankart lesion in a concavity-compression cadaveric model compared with single-row technique.Our aim was to examine the dynamic stability and ultimate displacement of single- vs double-row repair techniques for acute bony Bankart lesions Methods: Testing was performed on 13 matched pairs of glenoids with simulated bony Bankart fractures with a defect width of 25% of the glenoid diameter. Half of the fractures were repaired with a double-row technique, while the contralateral glenoids were repaired with a single-row technique. To determine dynamic biomechanical stability and ultimate step-off of the repairs a 150 N load and 2000 cycles of internal-external rotation at 1 Hz was applied to specimens to simulate standard rehabilitation protocols. Toggle was quantified throughout cycling with a coordinate measuring machine. After cyclic loading, the fracture displacement was measured. 3D spatial measurements were calculated using MATLAB. Results: The double-row technique resulted in significantly (p=0.005) less displacement (mean=342.48 µm SD=300.64 µm) than single-row technique (mean=981.84 µm, SD=640.38 µm). Ultimate fracture displacement of double-row repair was significantly less (mean=792.23 µm, SD=333.85 µm, p=0.046) after simulated rehabilitation by internal-external rotation cycling compared to single-row repair (mean=1,267.38 µm, SD=640.38 µm). Conclusion: The double-row fixation technique for arthroscopic bony Bankart repair results in superior stability throughout simulated rehabilitation and decreases ultimate displacement in a concavity-compression cadaveric model.

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Ngoc, Le Thi Phuong, Khong Thi Thao Uyen, Nguyen Huu Nhan et Nguyen Thanh Long. « On a system of nonlinear pseudoparabolic equations with Robin-Dirichlet boundary conditions ». Communications on Pure & ; Applied Analysis 21, n^o 2 (2022) : 585. http://dx.doi.org/10.3934/cpaa.2021190.

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In this paper, we investigate a system of pseudoparabolic equations with Robin-Dirichlet conditions. First, the local existence and uniqueness of a weak solution are established by applying the Faedo-Galerkin method. Next, for suitable initial datum, we obtain the global existence and decay of weak solutions. Finally, using concavity method, we prove blow-up results for solutions when the initial energy is nonnegative or negative, then we establish here the lifespan for the equations via finding the upper bound and the lower bound for the blow-up times.

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Wang, Yu-Zhao, et Yan-Mei Wang. « The concavity of p-Rényi entropy power for doubly nonlinear diffusion equations and L-Gagliardo-Nirenberg-Sobolev inequalities ». Journal of Mathematical Analysis and Applications 484, n^o 1 (avril 2020) : 123698. http://dx.doi.org/10.1016/j.jmaa.2019.123698.

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Yang, G. C., et Z. Y. Li. « Positive Solutions of One-Dimensional p-Laplacian Problems with Superlinearity ». Symmetry 10, n^o 9 (26 août 2018) : 363. http://dx.doi.org/10.3390/sym10090363.

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We study one-dimensional p-Laplacian problems and answer the unsolved problem. Our method is to study the property of the operator, the concavity of the solutions and the continuity of the first eigenvalues. By the above study, the main difficulty is overcome and the fixed point theorem can be applied for the corresponding compact maps. An affirmative answer is given to the unsolved problem with superlinearity. A global growth condition is not imposed on the nonlinear term f. The assumptions of this paper are more general than the usual, thus the existing results cannot be utilized. Some recent results are improved from weak solutions to classical solutions and from p ≥ 2 to p ∈ ( 1 , ∞ ) .

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ABUNDO, M., L. ACCARDI et N. ROSATO. « A MARKOVIAN MODEL FOR COOPERATIVE INTERACTIONS IN PROTEINS ». Mathematical Models and Methods in Applied Sciences 05, n^o 06 (septembre 1995) : 835–63. http://dx.doi.org/10.1142/s0218202595000462.

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A stochastic model for cooperative interactions in proteins is proposed. The description is based on the theory of Markov’s chains and of birth-and-death processes. Even if the model depends only on two parameters: the mean probability p and the coupling capacity∆p, it presents a surprising wealth of qualitative behaviors when the two parameters are varied. In particular we provide numerical evidence of change of concavity of the stationary distribution at a critical value of the coupling capacity ∆p. The main mathematical feature is that the probability of creating a new chemical bond depends on the total number of bonds already present in the system. In this sense, we speak of a cooperative behavior.

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Segi, Naoki, Hiroaki Nakashima, Ryuichi Shinjo, Yujiro Kagami, Masaaki Machino, Sadayuki Ito, Jun Ouchida et al. « Vertebral Endplate Concavity in Lateral Lumbar Interbody Fusion : Tapered 3D-Printed Porous Titanium Cage versus Squared PEEK Cage ». Medicina 59, n^o 2 (15 février 2023) : 372. http://dx.doi.org/10.3390/medicina59020372.

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Background and Objectives: To prevent postoperative problems in extreme lateral interbody fusion (XLIF), it is critical that the vertebral endplate not be injured. Unintentional endplate injuries may depend on the cage. A novel porous titanium cage for XLIF has improved geometry with a tapered tip and smooth surface. We hypothesized that this new cage should lead to fewer endplate injuries. Materials and Methods: This retrospective study included 32 patients (mean 74.1 ± 6.7 years, 22 females) who underwent anterior and posterior combined surgery with XLIF for lumbar degenerative disease or adult spinal deformity from January 2018 to June 2022. A tapered 3D porous titanium cage (3DTi; 11 patients) and a squared PEEK cage (sPEEK; 21 patients) were used. Spinal alignment values were measured on X-ray images. Vertebral endplate concavity (VEC) was defined as concavity ≥ 1 mm of the endplate on computed tomography (CT) images, which were evaluated preoperatively and at 1 week and 3 months postoperatively. Results: There were no significant differences in the patient demographic data and preoperative and 3-month postoperative spinal alignments between the groups. A 3DTi was used for 25 levels and an sPEEK was used for 38 levels. Preoperative local lordotic angles were 4.3° for 3DTi vs. 4.7° for sPEEK (p = 0.90), which were corrected to 12.3° and 9.1° (p = 0.029), respectively. At 3 months postoperatively, the angles were 11.6° for 3DTi and 8.2° for sPEEK (p = 0.013). VEC was present in 2 levels (8.0%) for 3DTi vs. 17 levels (45%) for sPEEK (p = 0.002). After 3 months postoperatively, none of the 3DTi had VEC progression; however, eight (21%) levels in sPEEK showed VEC progression (p = 0.019). Conclusions: The novel 3DTi cage reduced endplate injuries by reducing the endplate load during cage insertion.

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Martins, Jorge N. R., António Mata, Duarte Marques et João Caramês. « Prevalence of C-shaped mandibular molars in the Portuguese population evaluated by cone-beam computed tomography ». European Journal of Dentistry 10, n^o 04 (octobre 2016) : 529–35. http://dx.doi.org/10.4103/1305-7456.195175.

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ABSTRACT Objective: The purpose of this study was to evaluate the prevalence of first and second C-shaped mandibular molars in a Western European population of Portuguese Caucasians. Materials and Methods: Patients having both routine panoramic radiograph and presurgical cone-beam computed tomography (CBCT) exams were selected. The CBCT examination was performed at five different axial levels and the mandibular molars were classified as C-shape according to the Fan criteria. Differences between genders, age groups, left and right side, type of tooth, and root concavity side were determined. The molars were classified as nonfused roots (NFRI–II), FRI–III, or single root with single canal (SS) groups, using the panoramic radiograph. The prevalence of C-shaped anatomy was calculated to each group. Results: A total of 1783 teeth (695 first molars and 1088 second molars) from 792 patients were included in the study. The prevalence of C-shaped configurations was 0.6% and 8.5% to mandibular first and second molars, respectively. The differences between gender, teeth, and root concavity direction were considered statistically significant (P < 0.05). The FR had a significantly higher rate of C-shapes when compared to NFR (P < 0.05). Intrarater reliability was 93.6%. Conclusions: The FR radiographic appearance may be considered a predictor of this anatomy. Second mandibular molars and females had a higher incidence ratio. Apparently, the mandibular C-shaped anatomy is more common in the population of this study than that has been previously reported for the European population.

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Satitpitakul, Vannarut, Parichart Taweekitikul, Vilavun Puangsricharern, Ngamjit Kasetsuwan, Usanee Reinprayoon et Thanachaporn Kittipibul. « Alteration of corneal biomechanical properties in patients with dry eye disease ». PLOS ONE 16, n^o 7 (12 juillet 2021) : e0254442. http://dx.doi.org/10.1371/journal.pone.0254442.

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Purpose To evaluate the association between symptoms and signs of dry eye diseases (DED) with corneal biomechanical parameters. Methods This cross-sectional study enrolled 81 participants without history of ocular hypertension, glaucoma, keratoconus, corneal edema, contact lens use, diabetes, and ocular surgery. All participants were evaluated for symptoms and signs of DED using OSDI questionnaire, tear film break-up time (TBUT), conjunctival and corneal staining (NEI grading) and Schirmer test. Corneal biomechanical parameters were obtained using Corvis ST. Mixed-effects linear regression analysis was used to determine the association between symptoms and signs of DED with corneal biomechanical parameters. Difference in corneal biomechanical parameter between participants with low (Schirmer value ≤10 mm; LT group) and normal (Schirmer value >10mm; NT group) tear production was analyzed using ANCOVA test. Results The median OSDI scores, TBUT, conjunctival and corneal staining scores as well as Schirmer test were 13±16.5 (range; 0–77), 5.3±4.2 seconds (range; 1.3–11), 0±1 (range; 0–4), 0±2 (ranges; 0–9) and 16±14 mm (range; 0–45) respectively. Regression analysis adjusted with participants’ refraction, intraocular pressure, and central corneal thickness showed that OSDI had a negative association with highest concavity radius (P = 0.02). The association between DED signs and corneal biomechanical parameters were found between conjunctival staining scores with second applanation velocity (A2V, P = 0.04), corneal staining scores with second applanation length (A2L, P = 0.01), Schirmer test with first applanation time (A1T, P = 0.04) and first applanation velocity (P = 0.01). In subgroup analysis, there was no difference in corneal biomechanical parameters between participants with low and normal tear production (P>0.05). The associations were found between OSDI with time to highest concavity (P<0.01) and highest displacement of corneal apex (HC-DA, P = 0.04), conjunctival staining scores with A2L (P = 0.01) and A2V (P<0.01) in LT group, and Schirmer test with A1T (P = 0.02) and HC-DA (P = 0.03), corneal staining scores with A2L (P<0.01) in NT group. Conclusions According to in vivo observation with Corvis ST, patients with DED showed more compliant corneas. The increase in dry eye severity was associated with the worsening of corneal biomechanics in both patients with low and normal tear production.

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JENČOVÁ, ANNA, et MARY BETH RUSKAI. « A UNIFIED TREATMENT OF CONVEXITY OF RELATIVE ENTROPY AND RELATED TRACE FUNCTIONS, WITH CONDITIONS FOR EQUALITY ». Reviews in Mathematical Physics 22, n^o 09 (octobre 2010) : 1099–121. http://dx.doi.org/10.1142/s0129055x10004144.

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We consider a generalization of relative entropy derived from the Wigner–Yanase–Dyson entropy and give a simple, self-contained proof that it is convex. Moreover, special cases yield the joint convexity of relative entropy, and for Tr K* Ap K B1-p Lieb's joint concavity in (A, B) for 0 < p < 1 and Ando's joint convexity for 1 < p ≤ 2. This approach allows us to obtain conditions for equality in these cases, as well as conditions for equality in a number of inequalities which follow from them. These include the monotonicity under partial traces, and some Minkowski type matrix inequalities proved by Carlen and Lieb for [Formula: see text]. In all cases, the equality conditions are independent of p; for extensions to three spaces they are identical to the conditions for equality in the strong subadditivity of relative entropy.

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BEN SLIMANE, MOURAD, et BORHEN HALOUANI. « MULTIFRACTAL FORMALISM OF OSCILLATING SINGULARITIES FOR RANDOM WAVELET SERIES ». Fractals 23, n^o 02 (28 mai 2015) : 1550005. http://dx.doi.org/10.1142/s0218348x1550005x.

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The oscillating multifractal formalism is a formula conjectured by Jaffard expected to yield the spectrum d(h, β) of oscillating singularity exponents from a scaling function ζ(p, s'), for p > 0 and s' ∈ ℝ, based on wavelet leaders of fractional primitives f-s' of f. In this paper, using some results from Jaffard et al., we first show that ζ(p, s') can be extended on p ∈ ℝ to a function that is concave with respect to p ∈ ℝ and independent on orthonormal wavelet bases in the Schwartz class. We also establish its concavity with respect to s' when p > 0. Then, we prove that, under some assumptions, the extended scaling function ζ(p, s') is the Legendre transform of the wavelet leaders density of f-s'. Finally, as an application, we study the validity of the extended oscillating multifractal formalism for random wavelet series (under the assumption of independence and laws depending only on the scale).

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Wolski, Grzegorz J., Paulina Nowicka-Krawczyk et William R. Buck. « Taxonomic revision of the Plagiothecium curvifolium complex ». PLOS ONE 17, n^o 11 (9 novembre 2022) : e0275665. http://dx.doi.org/10.1371/journal.pone.0275665.

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Supported by the examination of specimens from the entire range and by the analysis of type specimens and the diagnosis of individual names, morphological and genetic studies of the Plagiothecium curvifolium complex resulted in the conclusion that this taxon should be recognized as four separate taxa. In addition to P. curvifolium s.str., there is a variety that is proposed as a new combination–P. curvifolium var. recurvum; resurrection of the forgotten P. decursivifolium; and the description of a new species–P. imbricatum. The features that distinguish individual taxa focus primarily on: plant size; arrangement of leaves on the stem; the symmetry, dimensions, shape, concavity and folding of leaves; cell length; serration of the leaf apex; the shape of the decurrencies; the length of the sporophyte and the shape of the operculum. For all described taxa, the distribution, ecological preferences, key to their identification and detailed photographic documentation have been provided.

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Jameson, G. J. O. « 2-convexity and 2-concavity in Schatten ideals ». Mathematical Proceedings of the Cambridge Philosophical Society 120, n^o 4 (novembre 1996) : 697–702. http://dx.doi.org/10.1017/s0305004100001651.

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The properties p-convexity and q-concavity are fundamental in the study of Banach sequence spaces (see [L-TzII]), and in recent years have been shown to be of great significance in the theory of the corresponding Schatten ideals ([G-TJ], [LP-P] and many other papers). In particular, the notions 2-convex and 2-concave are meaningful in Schatten ideals. It seems to have been noted only recently [LP-P] that a Schatten ideal has either of these properties if the underlying sequence space has. One way of establishing this is to use the fact that if (E, ‖ ‖E) is 2-convex, then there is another Banach sequence space (F, ‖ ‖F) such that ‖x;‖ = ‖x2‖F for all x ε E. The 2-concave case can then be deduced using duality, though this raises some difficulties, for example when E is inseparable.

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RUSKAI, MARY BETH. « ERRATUM : "LIEB'S SIMPLE PROOF OF CONCAVITY OF (A, B) ↦ Tr Ap K† B1-p K AND REMARKS ON RELATED INEQUALITIES" ». International Journal of Quantum Information 04, n^o 04 (août 2006) : 747–48. http://dx.doi.org/10.1142/s0219749906002031.

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TEDESCO, ANAZÉLIA M., et ALEXANDRE P. AGUIAR. « Revision and phylogeny of the rare Priotomis Townes (Hymenoptera, Ichneumonidae, Cryptinae), with three new species and first description of the male ». Zootaxa 3031, n^o 1 (16 septembre 2011) : 14. http://dx.doi.org/10.11646/zootaxa.3031.1.2.

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Priotomis vinhai Tedesco, sp. nov., from the restingas of southeastern Brazil, P. echyrus Tedesco, sp. nov., from Mexico and Costa Rica, and Priotomis flammatus Tedesco, sp. nov., from Panama and Brazil, are described and illustrated. The monophyly of the genus and the relationships of its species were cladistically tested using implied weighting, in a matrix with 22 species, including four species of Priotomis, and 92 external structural characters. Concavity constants (K) from 1 to 6 were tested. All analyses recovered Priotomis as monophyletic. A redescription of Priotomis is presented, combining the original definition with original information, expanding the limits of the genus. All results indicate P. vinhai, sp. nov. as the basal-most species of the genus; all results with K=2–5 recovered the apical clade P. rana + (P. echyrus, sp. nov. + P. flammatus, sp. nov.). An updated key to species is presented. Additional distribution records are provided, expanding the known range of Priotomis to 41º11’ latitude degrees, from Mexico to Argentina.

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BERTANI, ROGÉRIO, ROBERTO HIROAKI NAGAHAMA et CAROLINE SAYURI FUKUSHIMA. « Revalidation of Pterinopelma Pocock 1901 with description of a new species and the female of Pterinopelma vitiosum (Keyserling 1891) (Araneae : Theraphosidae : Theraphosinae) ». Zootaxa 2814, n^o 1 (11 avril 2011) : 1. http://dx.doi.org/10.11646/zootaxa.2814.1.1.

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We revalidate the theraphosid genus Pterinopelma Pocock 1901, describe the female of P. vitiosum for first time and Pterinopelma sazimai sp. nov. from Brazil. These two species were included in a matrix with 35 characters and 32 taxa and were analyzed both with all characters having same weight and with implied weights. SearAraneaeches considering all characters non-additive or some additive were also carried out. The preferred tree, obtained with implied weights, concavity 6 and all characters non-additive shows that Pterinopelma is a monophyletic genus sister to the clade Lasiodora (Vitalius + Nhandu). The presence of denticles on the prolateral inferior male palpal bulb keel is a synapomorphy of the genus.

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Peris-Martínez, Cristina, María Amparo Díez-Ajenjo, María Carmen García-Domene, María Dolores Pinazo-Durán, María José Luque-Cobija, María Ángeles del Buey-Sayas et Susana Ortí-Navarro. « Evaluation of Intraocular Pressure and Other Biomechanical Parameters to Distinguish between Subclinical Keratoconus and Healthy Corneas ». Journal of Clinical Medicine 10, n^o 9 (28 avril 2021) : 1905. http://dx.doi.org/10.3390/jcm10091905.

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(1) Purpose: To assess the main corneal response differences between normal and subclinical keratoconus (SCKC) with a Corvis® ST device. (2) Material and Methods: We selected 183 eyes of normal patients, of a mean age of 33 ± 9 years and 16 eyes of patients with SCKC of a similar mean age. We measured best corrected visual acuity (BCVA) and corneal topography with a Pentacam HD device to select the SCKC group. Biomechanical measurements were performed using the Corvis® ST device. We carried out a non-parametric analysis of the data with SPSS software (Wilcoxon signed rank-test). (3) Results: We found statistically significant differences between the control and SCKC groups in some corneal biomechanical parameters: first and second applanation time (p = 0.05 and p = 0.02), maximum deformation amplitude (p = 0.016), highest concavity radius (p = 0.007), and second applanation length and corneal velocity ((p = 0.039 and p = 0.016). (4) Conclusions: Our results show that the use of normalised biomechanical parameters provided by noncontact tonometry, combined with a discriminant function theory, is a useful tool for detecting subclinical keratoconus.

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Kawohl, Bernd. « How I met the normalized p-Laplacian $$\varDelta _p^N$$ and what we know now about mean values and concavity properties ». Journal of Elliptic and Parabolic Equations 6, n^o 1 (23 mars 2020) : 113–21. http://dx.doi.org/10.1007/s41808-020-00060-2.

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Parada, Stephen A., K. Aaron Shaw, Colleen Moreland, Douglas R. Adams, Mickey S. Chabak et Matthew T. Provencher. « Variations in the Anatomic Morphology of the Lateral Distal Tibia : Surgical Implications for Distal Tibial Allograft Glenoid Reconstruction ». American Journal of Sports Medicine 46, n^o 12 (31 août 2018) : 2990–95. http://dx.doi.org/10.1177/0363546518793880.

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Background: Distal tibial allograft glenoid augmentation has been introduced as a viable treatment approach for glenoid bone loss in conjunction with shoulder instability. No previous study, however, has assessed the morphologic variation of the distal tibia at the incisura as it relates to graft dimensions for glenoid augmentation. Increased concavity at the lateral distal tibia necessitates removal of the lateral cortex to obtain a flat surface, which may have implications for the strength of surgical fixation. Purpose: To assess the morphologic variation of the distal tibia at the incisura as it relates to graft dimensions for glenoid augmentation. Study Design: Descriptive laboratory study. Methods: Magnetic resonance images of the ankle were reviewed for morphology assessment of the appearance and depth of the distal tibia. A classification system was created reflecting the suitability for glenoid augmentation. Type A tibias contained a flat contour of the lateral tibia at the articular surface, indicative of an ideal graft. Type B tibias had slight concavity with a central depth <5 mm and were deemed acceptable grafts. Type C tibias had deep concavity with a central depth >5 mm and were deemed unacceptable. Statistical analysis was performed via univariate analyses to compare patient demographics against acceptable morphology for glenoid augmentation. Results: Eighty-five study patients met inclusion criteria (53 male, 32 female; mean age ± SD, 35.1 ± 10.3 years). Overall, 12 patients (14.1%) demonstrated type A morphology, with 61 patients (71.8%) having type B morphology for a total of 85.9% of acceptable grafts for glenoid augmentation. The interrater reliability was moderate to strong between observers (kappa value = 0.841). On univariate analysis, sex was the only variable significantly associated with an acceptable graft, with 100% of female patients having acceptable morphology, as compared with 77% of male patients ( P = .004). Conclusion: Variable morphology of the distal tibia at the incisura was found: 14.1% of patients demonstrated an ideal morphology for glenoid augmentation; an additional 71.8% were deemed suitable for graft usage; and 14.1% of tibias had unacceptable morphology. Sex was a significant factor for predicting acceptable grafts. Clinical Relevance: This information will assist surgeons in accepting or rejecting grafts based on the epidemiology of the distal tibial morphology as it relates to glenoid augmentation.

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Öztürk, Güncel. « Improvement of Alar Concavity With Scroll Ligament Preservation : Sandwich Technique ». Aesthetic Surgery Journal 40, n^o 10 (21 janvier 2020) : 1064–75. http://dx.doi.org/10.1093/asj/sjaa018.

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Abstract Background Excessive concavity of the lower lateral crura can cause significant aesthetic problems for the nasal tip and can be associated with significant functional problems, such as insufficiencies in the external nasal valve. Objectives The aim of this study was to develop a novel technique for the improvement of several alar concavities that preserve the scroll area. Methods In this retrospective study, 51 primary rhinoplasty patients with unoperated alar concavity deformities were assessed. Alar concavities were repaired with alar strut grafts and a superior transposition flap or superior-based sliding flap, which were designed with the “sandwich” technique. Additionally, the scroll ligament was completely preserved in the 2 variants of the technique. All patients who were included in the study were assessed with the Rhinoplasty Outcome Evaluation (ROE) questionnaire before surgery and at their 1-year follow-up appointment. Results The median age of patients was 29.2 years (range, 19-49 years). The ROE scores ranged between 90 and 100 points after 1 year. The median score was 91.2 points, and this was significantly increased at the 1-year follow-up appointment (P = 0.002). Patient satisfaction was found to be excellent in 92% of the included patients. Patients were also evaluated in terms of functionality. The patients’ patency scores increased to 9.4 from 6.1 (out of 10) after a 12-month follow-up (P = 0.003). Conclusions This “sandwich” technique involves a combination of superior transposition flaps, superior-based sliding flaps, and alar strut grafts. Thus, patients who receive this treatment may also benefit from new flap techniques and vertical and longitudinal scroll ligament preservation. This new technique presents a novel and easy method for the reconstruction of severe alar concavities. Level of Evidence: 4

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Chen, Yuxuan, et Jiangbo Han. « Global existence and nonexistence for a class of finitely degenerate coupled parabolic systems with high initial energy level ». Discrete & ; Continuous Dynamical Systems - S 14, n^o 12 (2021) : 4179. http://dx.doi.org/10.3934/dcdss.2021109.

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In this paper, we consider a class of finitely degenerate coupled parabolic systems. At high initial energy level <inline-formula><tex-math id="M1">\begin{document}$ J(u_{0})>d $\end{document}</tex-math></inline-formula>, we present a new sufficient condition to describe the global existence and nonexistence of solutions for problem (1)-(4) respectively. Moreover, by applying the Levine's concavity method, we give some affirmative answers to finite time blow up of solutions at arbitrary positive initial energy <inline-formula><tex-math id="M2">\begin{document}$ J(u_{0})>0 $\end{document}</tex-math></inline-formula>, including the estimate of upper bound of blowup time.

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Shahura, Fairudz, Oni Soesanto et Fatma Indriani. « PENERAPAN METODE RBPNN UNTUK KLASIFIKASI KANKER PAYUDARA ». KLIK - KUMPULAN JURNAL ILMU KOMPUTER 3, n^o 2 (5 octobre 2016) : 135. http://dx.doi.org/10.20527/klik.v3i2.51.

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Breast cancer is the most commonly diagnosed cancer in women. Breast cancer cases are increasing each year. Therefore, early detection of breast cancer plays an important role in anticipating the spread of cancer. Fine-needle aspiration (FNA) biopsy is one way to detect breast cancer. FNA is a method of taking the majority of tissue with a syringe that is intended to aid in the diagnosis of various tumor diseases. The FNA samples that have been studied generate ten characteristics, namely radius, texture, perimeter, area, compactness, smoothness, concavity, concave points, symmetry, and fractal dimension. These characteristics are used to classify benign and malignant breast cancer. To classify breast cancer, Radial Basis Probabilistic Neural Network (RBPNN) required. This study aims to determine how the performance of the method of Radial Basis Probabilistic Neural Network for classifying breast cancer. The accuracy was found to be equal 93.19% for training data, and 90.35% for testing data.Keywords: Radial Basis Probabilistic Neural Network, Classification, Breast Cancer.Kanker payudara merupakan penyakit yang paling banyak menyerang kaum wanita. Penderita penyakit kanker payudara semakin meningkat pada tiap tahunnya. Oleh karena itu deteksi dini kanker payudara memegang peranan penting dalam mengantisipasi penyebaran kanker. Salah satu cara untuk mendeteksi kanker payudara adalahÂ dengan fine-needle aspiration (FNA) biopsy. FNA merupakan suatu metode pengambilan sebagian jaringan tubuh manusia dengan jarum suntik yang bertujuan untuk membantu diagnosis berbagai penyakit tumor. Sampel FNA yang telah diteliti menghasilkan sepuluh karakteristik, yaitu radius, texture, perimeter, area, compactness, smoothness, concavity, concave points, symmetry, dan fractal dimension. Kesepuluh karakteristik tersebut digunakan untuk mengklasifikasikan kanker payudara jinak dan ganas. Untuk mengklasifikasi tingkat keganasan dari kanker payudara dapat dilakukan dengan metode Radial Basis Probabilistic Neural Network (RBPNN). Penelitian ini bertujuan untuk mengetahui bagaimana performansi metode Radial Basis Probabilistic Neural Network untuk mengklasifikasikan kanker payudara. Dari hasil penelitian didapat akurasi 93.19% untuk data training, serta 90.35% untuk data testing.Kata kunci : Radial Basis Probabilistic Neural Network, Klasifikasi, Breast Cancer.

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Ocak, Yunus, Orhan Cicek, Nurhat Ozkalayci et Hande Erener. « Investigation of the Relationship between Sagittal Skeletal Nasal Profile Morphology and Malocclusions : A Lateral Cephalometric Film Study ». Diagnostics 13, n^o 3 (27 janvier 2023) : 463. http://dx.doi.org/10.3390/diagnostics13030463.

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The aim of this study was to evaluate the relationship between skeletal sagittal nasal profile morphology and sagittal skeletal malocclusions. Regarding lateral cephalometric films, the study was conducted in a total of 135 individuals without any prior orthodontic treatment (mean age of 17.91 ± 1.91), including 49 males (mean age 17.91 ± 1.16) and 86 females (mean age 17.78 ± 1.91 years). The groups were divided into two groups as male and female according to gender, and three groups as skeletal Class 1, Class 2, and Class 3 according to the Steiner’s ANB angle. In addition, skeletal groups were compared within groups by dividing into two groups of male and female. A total of eight parameters, three skeletal sagittal angular (SNA, SNB, and ANB angles), four nasal linear (R-A, N-A, N-ANS, and N-R distances) and one nasal angular (N1-N2/N2-R angle), were measured on each cephalometric film. The arithmetic mean and standard deviation of all measured nasal parameters were calculated. For statistical analysis, independent sample t-test and one-way analysis of variance (One-Way ANOVA) were used for normally distributed data, and Mann Whitney U and Kruskal Wallis tests were used for data that did not show normal distribution. For statistical analysis, p < 0.05 was considered significant. R-A, N-A, and N-ANS linear nasal parameters differed significantly between the male and female groups, which were evaluated regardless of the skeletal groups, with a higher rate in males (p < 0.05). N-R linear nasal parameter showed a statistically significant difference between skeletal malocclusion groups, which were evaluated regardless of gender. N-R distance was found to be significantly longer in skeletal Class 3 individuals than in Class 1 and 2 individuals (p < 0.05). There was no statistically significant difference in nasal bone concavity angle in all groups (p > 0.05). R-A and N-A linear nasal parameters showed statistically significant differences between male and female sex groups in all skeletal malocclusion classes (p < 0.05). At first, results showed that males had longer measurements than females in all linear nasal parameters. Second, longer measurements were found in all linear nasal parameters in skeletal Class 3 individuals than those in skeletal Class 1 and Class 2 individuals. Third, the nasal bone concavity angle was greater in skeletal Class 2 individuals than the others.

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