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Cryptography and steganography are employed to secure digital data transfers. We introduced an efficient region-based steganography pipeline to enhance security by concealing confidential information within an image. Our approach involves isolating the blue channel from the cover image, partitioning it into blocks, identifying smooth blocks, and embedding the message in the Least Significant Bit (LSB). Smooth blocks were determined using the Pixel Value Differencing (PVD) method, which compares a specific pixel value to the block's average pixel value (M) of the particular block. Concealed areas exhibit greater imperceptibility in smooth regions than in rough ones. We performed experiments on a carefully chosen image set and assessed the performance of the region-based steganography method using widely recognized metrics such as PSNR, MSE, and SSIM. These metrics were applied to a widely recognized benchmark dataset for comparison. Results indicate significantly improved PSNR and SSIM levels for selected images, confirming the suitability of smooth, edge-free regions for concealing hidden messages with greater imperceptibility. We compared our method with recently published steganography methods and observed a significant enhancement in its ability to conceal information effectively. [ABSTRACT FROM AUTHOR]

The accurate calculation of reaction rates from experimental data is crucial for understanding and characterizing chemical processes. However, the presence of noise in experimental data can introduce errors in rate calculations. In this study, we introduced a novel approach that utilizes the Legendre series expansion method to directly derive smooth reaction rates from noisy experimental data, eliminating the need for numerical differentiation methods. This approach proves to be highly effective in handling noisy thermogravimetric analysis (TGA) data obtained from the thermal decomposition of specific polymers. We demonstrated the robustness and reliability of this method and provided Gnu Octave codes as a free alternative to MATLAB, making the implementation more accessible. Furthermore, the smooth reaction rates obtained were used to evaluate the activation energy using the Friedman isoconversional method. The results showed excellent agreement with those obtained using the Vyazovkin integral method. Additionally, the proposed method can be applied to obtain smooth derivative thermogravimetric (DTG) curves using noisy TGA data set. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus, the causative agent of seafood-associated gastroenteritis, undergoes wrinkly and smooth colony switching on the plate. The wrinkly spreader grew faster, had stronger motility and biofilm capacity when compared with the smooth one. However, whether the two phenotypes differ in their virulence still needs to be further investigated. In this study, the data showed that the smooth spreader had stronger virulence phenotypes, including the cytotoxicity against HeLa cells, antibacterial activity against E. coli, adhesive capacity toward HeLa cells, and lethality in zebrafish, relative to the wrinkly one. However, the colony morphology variation had no influence on the haemolytic activity. The mRNA levels of major virulence genes including T3SS1, T6SS1, and T6SS2 were significantly enhanced in the smooth colonies relative to those in the wrinkly colonies. Taken together, the presented work highlighted the different virulence profiles of the wrinkly and smooth colony phenotypes. [ABSTRACT FROM AUTHOR]

This paper is dedicated to the question of surjectivity of the Cauchy-Riemann operator ∂ ¯ on spaces E V (Ω , E) of C ∞ -smooth vector-valued functions whose growth on strips along the real axis with holes K is induced by a family of continuous weights V . Vector-valued means that these functions have values in a locally convex Hausdorff space E over C . We derive a counterpart of the Grothendieck-Köthe-Silva duality O (C \ K) / O (C) ≅ A (K) with non-empty compact K ⊂ R for weighted holomorphic functions. We use this duality and splitting theory to prove the surjectivity of ∂ ¯ : E V (Ω , E) → E V (Ω , E) for certain E. This solves the smooth (holomorphic, distributional) parameter dependence problem for the Cauchy-Riemann operator on E V (Ω , C) . [ABSTRACT FROM AUTHOR]

We introduce NC-SARAH for non-convex optimization as a practical modified version of the original SARAH algorithm that was developed for convex optimization. NC-SARAH is the first to achieve two crucial performance properties at the same time—allowing flexible minibatch sizes and large step sizes to achieve fast convergence in practice as verified by experiments. NC-SARAH has a close to optimal asymptotic convergence rate equal to existing prior variants of SARAH called SPIDER and SpiderBoost that either use an order of magnitude smaller step size or a fixed minibatch size. For convex optimization, we propose SARAH++ with sublinear convergence for general convex and linear convergence for strongly convex problems; and we provide a practical version for which numerical experiments on various datasets show an improved performance. [ABSTRACT FROM AUTHOR]

It is shown that a simple closed curve in C n that is a uniform limit of rectifiable simple closed curves each of which has nontrivial polynomial hull has itself nontrivial polynomial hull. In case the limit curve is rectifiable, the hull of the limit is shown to be the limit of the hulls. It is also shown that every rectifiable simple closed curve in C n , n ≥ 2 , can be approximated in total variation norm by a polynomially convex, rectifiable simple closed curve that coincides with the original curve except on an arbitrarily small segment. As a corollary, it is shown that every rectifiable arc in C n , n ≥ 2 , is contained in a polynomially convex, rectifiable simple closed curve. [ABSTRACT FROM AUTHOR]

Various topological properties of the smooth, Lipschitz, convex, quasiconvex, uniform and QED domains in Riemannian n-dimensional manifolds are investigated. It has been established that Riemannian manifolds are weakly flat spaces in the terminology of general metric measure spaces. Moreover, several sufficient conditions on continuous and homeomorphic extensions to the boundary of η -quasisymmetries, weakly H-quasisymmetries and ω -quasimöbius homeomorphisms between domains in Riemannian manifolds are obtained. The relationship between the above mapping classes is provided too. [ABSTRACT FROM AUTHOR]

Basalt fiber is more cost-effective than carbon fiber and has superior mechanical and chemical properties than glass fiber. Most existing studies considered the use of micro basalt fibers in concrete matrix to reduce shrinkage and control micro cracks. However, macro fibers are often required to reinforce concrete material when large deformation and macro cracks in structural elements are of concern. Very few studies have been reported for macro Basalt Fiber Reinforced Polymer (BFRP) fibers to improve mechanical properties of concrete. The geometric characteristics of macro fibers are critical for concrete reinforcement. It is known that macro fibers with smooth surface possess poor bond strength. To enhance the bonding properties between macro BFRP fibers and concrete, in this experimental study, pullout tests on macro BFRP fibers with various geometric forms from different grades of mortar matrix were carried out. Smooth fiber, etched fiber and double-helix fiber were manufactured and evaluated. The effects of embedded length and matrix strength are also investigated through pullout behavior of single BFRP fiber. The variation of etched intervals of etched fibers on bond strength was also taken into account. It was found that the double-helix fiber outperformed other types of fibers in terms of strength utilization ratio and energy absorption capability. An empirical model for interfacial bond-slip relation was proposed based on the test results. Based on results of pullout tests, the outstanding performance of double-helix BFRP fiber was further verified by examining the mechanical properties of normal-strength concrete specimens reinforced with different types of macro BFRP fibers. [ABSTRACT FROM AUTHOR]

In recent years, protein decomposition has become of increasing interest for the use in forensic estimation of the postmortem interval (PMI). Especially skeletal muscle tissue has proven to be a prime target tissue, among other reasons, due to its large abundance in the human body. In this regard, it is important to know whether there are any intra- and intermuscular differences in the behavior of protein degradation. Thus, samples from different locations within several skeletal muscles as well as from cardiac and smooth muscle tissue samples were collected from three autopsy cases with varying degree of decomposition. Samples were analyzed by SDS-PAGE and Western blotting and compared for protein degradation patterns. Intramuscular variations turned out to be minimal and without major influence for the use of the method. Observed intermuscular differences provide possibilities for future improvement of the precision and temporal application range. The results of this study show the strengths and current limitations of protein degradation-based PMI estimation and provide a deeper understanding of intraindividual postmortem protein degradation processes. [ABSTRACT FROM AUTHOR]

The 2-periodic function, W ∗ ∈ C 2 (R) is constructed in such a way that the sum ∑ k = 1 n (- 1) k + 1 f (k) can be efficiently estimated for any n ∈ N ∪ { ∞ } and for every f ∈ C 4 [ 1 , ∞) having ∫ 1 ∞ | f (4) (x) | d x < ∞ . [ABSTRACT FROM AUTHOR]

Hammerhead sharks are among the most intriguing yet imperiled groups of large sharks globally. Until recently, our understanding of their biology, movements, diet, and life histories was challenged by a lack of studies. In recent years there has been a surge of published studies on this group of sharks, incorporating new information on age and growth, behavior, and the threats they face. Here we summarize and compare what is known on the biology and conservation of the three largest species of hammerhead sharks: the great hammerhead (Sphyrna mokarran), the scalloped hammerhead (Sphyrna lewini), and the smooth hammerhead (Sphyrna zygaena). We chose these species since they are the most well-studied of the hammerheads, and also because they are commonly captured in target and non-target fisheries worldwide. Thus, we also discuss population trends and the vulnerabilities of each species, and make recommendations for future studies on these fascinating and complex elasmobranch fishes. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for optimizing pre-calculated collision-free paths of differential-drive wheeled robots. The main advantage of this methodology is that optimization is done by considering the kinematics and mechanical constraints of the mobile robot. In accordance to this proposal, the optimized path is achieved by applying recursively a local smoothing on an initial path which is originally modeled as a one-dimensional piecewise linear function. By this recursive smoothing, it can be ensured that the original piecewise linear function can be transformed into a smooth one that fulfill the constraints established by the kinematic equations of the wheeled mobile in terms of a minimum radius of curvature. As a result of this, a trajectory which guarantees lower power consumption and lower mechanical wear, is obtained. To show the better performance of the proposed approach, numerical simulation results are contrasted to those obtained from other reported methods with regards to path length, minimum radius of curvature, cross track error, continuity and resulting acceleration. [ABSTRACT FROM AUTHOR]

We present a simple thermal treatment with the antimony source for the metal-organic chemical vapor deposition of thin GaSb films on GaAs (111) substrates for the first time. The properties of the as-grown GaSb films are systematically analyzed by scanning electron microscopy, atomic force microscopy, x-ray diffraction, photo-luminescence (PL) and Hall measurement. It is found that the as-grown GaSb films by the proposed method can be as thin as 35 nm and have a very smooth surface with the root mean square roughness as small as 0.777 nm. Meanwhile, the grown GaSb films also have high crystalline quality, of which the full width at half maximum of the rocking-curve is as small as 218 arcsec. Moreover, the good optical quality of the GaSb films has been demonstrated by the low-temperature PL. This work provides a simple and feasible buffer-free strategy for the growth of high-quality GaSb films directly on GaAs substrates and the strategy may also be applicable to the growth on other substrates and the hetero-growth of other materials. [ABSTRACT FROM AUTHOR]

Realistic 3D human model reconstruction is an important component in computer graphics and computer vision. In particular, texturing on the surface of models is a key stage of reconstruction. In this paper, we dispose the texture mapping on the model's surface as an optimization of image stitching, and present an effective method to generate a seamless, integrated and smooth texture on the surface of 3D human model. First, we build a corresponding Markov Random Field model with respect to color images and triangular meshes of the surface. On the basis of $$\alpha$$ -expansion optimization for this Markov Random Field model, a 2D translation coordinate of color image, as an adaptive iterative factor, is introduced into the optimization to match the color content at the boundary of adjacent meshes. That compensates for the misalignment of adjacent color images, which caused by the inaccuracy of depth data and multi-view misregistration. Then we apply Poisson blending to a composite vector field in gradient domain, to resolve the small but noticeable illumination variations between different color images. To repair the blank regions, we parameterize the model's surface and project it onto a 2D plane. Then the K-Nearest Neighbor algorithm is applied to fill up the blank regions with texture contents. Finally, we evaluate our method by comparison with another three advanced methods on some human models, and the results demonstrate that our method of images stitching creates a best texture on the surface of 3D human model both in visual effect and quantitative analysis. [ABSTRACT FROM AUTHOR]

A smoothed representation (based on natural exponential and logarithmic functions) for the canonical piecewise-linear model, is presented. The result is a completely differentiable formulation that exhibits interesting properties, like preserving the parameters of the original piecewise-linear model in such a way that they can be directly inherited to the smooth model in order to determine their parameters, the capability of controlling not only the smoothness grade, but also the approximation accuracy at specific breakpoint locations, a lower or equal overshooting for high order derivatives in comparison with other approaches, and the additional advantage of being expressed in a reduced mathematical form with only two types of inverse functions (logarithmic and exponential). By numerical simulation examples, this proposal is verified and well-illustrated. [ABSTRACT FROM AUTHOR]

Dyslipidemia is a risk factor for intimal hyperplasia (IH). Key to IH is vascular smooth muscle cell (VSMC) migration. Thrombospondin-1 (TSP-1) is a matricellular protein that stimulates VSMC migration. Hypothesis: HDL will inhibit and LDL will augment TSP-1-induced VSMC chemotaxis. VSMC chemotaxis will be inhibited by the HDL moiety, S1P, through the S1PR1 receptor, and augmented by the LDL component, LPA, through the LPAR1 receptor. The goal of this study was to determine the effect of HDL and LDL and their receptors on TSP-1-induced VSMC chemotaxis. For VSMC chemotaxis to TSP-1 cells received the following pretreatments: low (25 µg/ml) or optimal (75 µg/ml) concentration of HDL, S1P, optimal (75 µg/ml) or high (175 µg/ml) concentration of LDL, or LPA. For the receptor studies, VSMCs were transfected with siRNA to S1PR1, S1PR3, LPAR1, LPAR2, LPAR3, or a S1PR2 receptor antagonist. The TSP-1-induced chemotaxis results were (1) HDL (25 µg/ml) or LDL (75 µg/ml) exhibited no effect on chemotaxis; (2) HDL (75 µg/ml) inhibited chemotaxis by 50.9 ± 8 % and S1P by 43.4 ± 11.6 %; (3) LDL (175 µg/ml) augmented chemotaxis by 30 ± 10.4 % and LPA by 25.6 ± 12.3 %; (4) S1PR1 and S1PR3 knockdown and S1PR2 antagonist-treated cells augmented chemotaxis; and (5) LPAR1 and LPAR2 knockdown inhibited and LPAR3 knockdown had no effect on chemotaxis. In conclusion, HDL/S1P inhibits, while LDL/LPA stimulates TSP-1-induced VSMC chemotaxis. The HDL/S1P effect is mediated by the S1PR1-3 receptors. The LDL/LPA effects are mediated by the LPAR1 and LPAR2 receptors, but not LPAR3. Therefore, lipids have significant effects on TSP-1-induced VSMC chemotaxis. [ABSTRACT FROM AUTHOR]

Tensor product smooths provide the natural way of representing smooth interaction terms in regression models because they are invariant to the units in which the covariates are measured, hence avoiding the need for arbitrary decisions about relative scaling of variables. They would also be the natural way to represent smooth interactions in mixed regression models, but for the fact that the tensor product constructions proposed to date are difficult or impossible to estimate using most standard mixed modelling software. This paper proposes a new approach to the construction of tensor product smooths, which allows the smooth to be written as the sum of some fixed effects and some sets of i.i.d. Gaussian random effects: no previously published construction achieves this. Because of the simplicity of this random effects structure, our construction is useable with almost any flexible mixed modelling software, allowing smooth interaction terms to be readily incorporated into any Generalized Linear Mixed Model. To achieve the computationally convenient separation of smoothing penalties, the construction differs from previous tensor product approaches in the penalties used to control smoothness, but the penalties have the advantage over several alternative approaches of being explicitly interpretable in terms of function shape. Like all tensor product smoothing methods, our approach builds up smooth functions of several variables from marginal smooths of lower dimension, but unlike much of the previous literature we treat the general case in which the marginal smooths can be any quadratically penalized basis expansion, and there can be any number of them. We also point out that the imposition of identifiability constraints on smoothers requires more care in the mixed model setting than it would in a simple additive model setting, and show how to deal with the issue. An interesting side effect of our construction is that an ANOVA-decomposition of the smooth can be read off from the estimates, although this is not our primary focus. We were motivated to undertake this work by applied problems in the analysis of abundance survey data, and two examples of this are presented. [ABSTRACT FROM AUTHOR]

We provide a complete classification up to isomorphism of all smooth convex lattice 3-polytopes with at most 16 lattice points. There exist in total 103 different polytopes meeting these criteria. Of these, 99 are strict Cayley polytopes and the remaining four are obtained as inverse stellar subdivisions of such polytopes. We derive a classification, up to isomorphism, of all smooth embeddings of toric threefolds in ℙ where N≤15. Again we have in total 103 such embeddings. Of these, 99 are projective bundles embedded in ℙ and the remaining four are blow-ups of such toric threefolds. [ABSTRACT FROM AUTHOR]

For capillary-gravity water waves with vorticity, in the absence of stagnation points, we prove that if the vorticity function has a Hölder continuous derivative then the free surface will be smooth. Furthermore, once we assume that the vorticity function is real analytic it will follow that the wave surface profile is also analytic. In particular this scenario includes the case of irrotational fluid flow where the vorticity is zero. [ABSTRACT FROM AUTHOR]

Aim: To determine whether protein kinase C (PKC) has any effect on the expression of cyclinD1, a key regulator of growth control and G/S transition, and to investigate the underlying molecular mechanisms of PKC involving the remodeling of the asthmatic airway smooth muscle (ASM). Methods: The treatment of synchronized ASM cells from asthmatic rats with PKC-specific agonist phorbol 12-myristate 13-acetate (PMA) and antagonist 2-{1-[3-(amidinothio) propyl]-1 H-indol-3-yl}-3-(1-methylindol-3-yl) maleimide methanesulfonate salt (Ro31-8220) was followed by the proliferation assay. PKCα and cyclinD1 expressions in ASM cells (ASMC) were detected by RT-PCR and Western blotting. The relation between PKCα and cyclinD1 was assessed by linear regression analysis. The effect of the construct recombinant plasmid pcDNA3.1-antisense cyclinD1 (pcDNA3.1-ascyclinD1) on the proliferation of ASMC was found to be induced by PMA. Results: The data showed phorbol ester-dependent PKCα promoted the proliferation of ASMC. The closely-positive correlation existed between the expression of PKCα and cyclinD1 at the transcriptional ( r=0.821, P<0.01) and transla-tional ( r=0.940, P<0.01) levels. pcDNA3.1-ascyclinD1 could inhibit the proliferation of ASMC. pcDNA3.1-ascyclinD1 almost completely attenuated the PMA-induced proliferation effect as Ro31-8220+pcDNA3.1. Conclusion: The proliferation of ASMC by PKC might by regulated by the cyclinD expression in asthmatic rats. [ABSTRACT FROM AUTHOR]

In this paper, the authors prove that if M n is a complete noncompact Kähler manifold with a pole p, and its holomorphic bisectional curvature is asymptotically non-negative to p, then it is a Stein manifold. [ABSTRACT FROM AUTHOR]

Introduction: In the 1970s and 1980s, uncemented, threaded acetabular components with smooth surface treatment were widely used in continental Europe for arthroplasty of the hip to overcome the high rate of aseptic loosening in cemented hip arthroplasty in young patients. There were several reports on short- and intermediate-term results, but information on survival in the longer term is not available at present. Materials and methods: In a consecutive series of 320 patients, 348 threaded cups with smooth surface treatment (221 Mecring and 127 Weill) had been implanted in combination with one type of uncemented stem. Patients were followed clinically and radiographically. The mean time of follow-up was 12.4 (range 10-15) years (Mecring 11.9 years, Weill 13.3 years). Results: In 76 hips the acetabular component had been revised (Mecring 56, Weill 20): 7 hips for infection and 69 for aseptic loosening. Of the remainder, the cup had migrated in 55 hips, and 32 hips were awaiting revision. Survival at 14 years was 63.8% (95%CI: 52.5-75.0%) for the Mecring and 76.2% (95%CI: 65.6-86.7%) for the Weill component. Radiolucent lines were present in 59 hips (31.9%). The median Harris Hip Score at follow-up was 84 points (Mecring 85, Weill 82). Radiographic loosening did not correlate with clinical outcome. Conclusion: These results support the view that smooth, threaded acetabular components do not provide satisfactory long-term fixation and should be abandoned. [ABSTRACT FROM AUTHOR]

Bezier spline fitting is a useful tool for generating smooth curves from a set of digitized points. These smooth curves may replace polylines for more accurate representation of natural linear entities. Maintaining its mathematical framework, the Bezier spline fitting can be improved so as to enhance its accuracy in representation. Key for improvement is developing methods to calculate tangent vectors and two coefficients for intermediate Bezier points, which allow higher flexibility of the control polygons than that of the Bezier spline fitting. Validity of the improved new spline fitting was tested by comparing accuracy of spline curves from the new spline fitting with spline curves from the Bezier spline fitting. Test was done using a set of mathematically simulated curves of the natural linear entities. [ABSTRACT FROM AUTHOR]

In a previous study, direct epithelial-stromal cell contacts via foot processes perforating the basement membrane were investigated in bronchioles of postnatal hamster lungs. In the present study, analogous postnatal epithelial foot processes have been found on stromal cells exhibiting active elastogenesis as determined by morphological criteria. In addition, elastin is prominently present close to the epithelium, but less so in the deeper layers, in the bronchioles of the 14-day-old hamster. The elastin often has an asymmetrical distribution around the subepithelial fibroblast with preference for secretion toward the epithelium. Thus, elastogenesis can now be linked to epithelial-stromal interactions at the temporal, functional, and morphological levels. [ABSTRACT FROM AUTHOR]

Muscles in the limbs change with age, but the aging process of urethral muscles is unknown. Therefore, we compared smooth and striated muscle content in the female rat urethra in young (12 month) and old (32 month) animals, using immunochemical techniques. All the striated skeletal fibers at both ages contain slow myosin. Urethral diameter does not change with age (young, 1.44±0.08 mm; old, 1.46±0.10 mm, n=5), nor does the external sphincter width (young, 0.088±0.016 mm; old, 0.080±0.017 mm, n=5). Neither smooth nor skeletal muscle volume in the urethra is changed with age (skeletal: young, 20.72±2.94%; old, 19.95±2.35%. Smooth: young, 22.26±2.98%; old, 26.75±2.35%, n=5). The external striated sphincter is separate and distinct from the pubococcygeal region of the levator ani muscle, but is closely apposed to another layer of longitudinally oriented fibers into the vaginal musculature. The morphometric analysis shows no difference in urethral architecture in aging female rats. [ABSTRACT FROM AUTHOR]

Copyright of Italian Journal of Neurological Sciences is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the role of injecting cultured fetal-bladder tissue into the region of the vesicoureteric orifice (VUO) to correct surgically produced vesicoureteric reflux (VUR), 12 Coopworth ewe lambs were studied. Four weeks after incising the intravesical segment of ureter, VUR was demonstrated by micturating cystourethrography. Bladder tissue was obtained from a fetal Coopworth lamb at 10 weeks' gestation, cultured in RPMI 1640, and injected into the region of the VUO of 1 ureter of each lamb using an open surgical approach. The lambs were killed between 1 and 6 months after the injection. Smooth-muscle cells from the cultured fetal bladder tissue were identified by the monoclonal antibodies HHF-35 for muscle alpha-actin and D33 for muscle desmin, and by electron microscopy. One lamb died of a gastrointestinal infection at 8 weeks of age. Of the remaining 11 animals, the injection of fetal-bladder tissue corrected the reflux in 7, while it was reduced in degree in 3 and persisted unchanged in 1. The reflux on the contralateral control side was also corrected in 6 ureters and improved in 2. Using histochemical techniques, grafted fetal-bladder tissue could not be differentiated from host tissue in the region of the VUO. Histopathological studies failed to show any injected tissue in distant organs. This study has shown that surgically-induced VUR in lambs was corrected or improved by the injection of cultured fetal-bladder tissue into the submucosa adjacent to the VUO. [ABSTRACT FROM AUTHOR]

Copyright of Andrologie (11662654) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vardenafil potently inhibits human phosphodiesterase 5 (PDE5) with an IC50 of 0.7?nM. Enhancement of nitric oxide (NO)-induced erections in rabbits by 0.1?mg/kg vardenafil is limited by its pharmacokinetic properties (Tmax=1?h; T1/2=1.2?h), although erectile effects have been observed after 7?h. In humans, vardenafil is rapidly absorbed (Tmax ˜40?min) and more slowly metabolized (T1/2˜4?h), with an absolute bioavailability of 14.5% (vs 40% for sildenafil). Although the consumption of high-fat meals does not affect the drug’s relative bioavailability, it retards intestinal absorption. Coadministration of CYP3A4 inhibitors such as ritonavir can affect hepatic metabolism. M1, an active metabolite of vardenafil, is a four-fold-less potent inhibitor of PDE5 than its parent compound, contributing approximately 7% to vardenafil’s overall efficacy. The side effects of all selective PDE5 inhibitors commonly include vasodilation, small reductions in blood pressure, headache, and nasal congestion.International Journal of Impotence Research (2004) 16, S34-S37. doi:10.1038/sj.ijir.3901213 [ABSTRACT FROM AUTHOR]

Copyright of Langenbecks Archiv fuer Chirurgie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)